Dynamic Analysis of Structures for Looms Industry

A Parametric Study

Bachelor Thesis , 2013 , 194 Pages , Grade: AA

Engineering - Civil Engineering

Ever since the existence of mankind, it has noticed a remarkable advancement in field of science and technology. Traditional hand weaving methods have been replaced by modern and speedy looms machine. With faster production rate, these machines proved to be a boon for textile manufacturers. However, they come with an unnoticed problem of “vibration”. Hence, there arises a need to study the effects of vibrations on the structural as well as non structural components of the building.

Here in this project, an attempt has been made to study the dynamic behavior of a structure for looms industry subjected to vibration due to operations of looms machine; by changing its various parameters. With an increase in demand of textile, more and more looms machines are being installed every day. While designing the structure to house these looms it becomes incumbent upon the designer to curtail the amplitude of vibrations within the permissible limits. One must also make sure that the frequency of structure is separated for operating frequency of machine by a good margin, so that the “Resonance Condition” can be avoided.

The looms machine fall under the category of reciprocating machine and have medium operating speed ranging from 100 rpm to 180 rpm. The main source of vibration is the Beating-Up motion. This generates a Harmonic Load due to the unbalanced force caused by the reciprocating sley movement. Hence, the designing of structure for looms industry is a complex process which needs prime considerations. The cost of dynamic analysis of these structure is paramount, hence a small fraction of amount is being spent might lead to inadequately constructed structures which may result in failure and shut downs, exceeding many times the cost of the capital investment required for properly designed and built structure.

Now, in such a case by executing parametric study, one can decide which parameter out of many is most sensitive to odd results, so that by varying those parameters only results can be brought to the required level and do not affect other reliable results. An attempt is made in the thesis to carry out a parametric study by using software STAAD. Pro
Following Parameters are studied in this thesis
1. Sizes of Column
2. Sizes of Beams
3. Story Height
4. Number of Stories

Effect of remedial measures like:
1. Cross Bracing below Plinth Level
2. Full Length Jacketing of Columns
3. Partial Length Jacketing of Columns
4. Cross Tie-Beams
5. Haunches at the Junction

TABLE OF CONTENTS

List of Figures

List of Tables

Chapter: 1 Introduction
1.1 History of Textile
1.2 History of Textile Industry in Surat City
1.3 Problem Definition

Chapter: 2 Aim of the Study

Chapter: 3 Literature Review

Chapter: 4 Theoretical Background
4.1 Vibration Theory
4.1.1 Definition
4.1.2 Types of Loads
4.1.3 Degree of Freedom
4.1.4 Resonance
4.2 Classification of Machines
4.2.1 Rotating Machinery
4.2.2 Reciprocating Machinery
4.2.3 Impulsive Machinery
4.3 Types of Foundations
4.3.1 Block-type foundation
4.3.2 Combined block-type foundation
4.3.3 Pile foundations
4.3.4 Wall type foundations
4.3.5 Framed-type foundation
4.4 Load Acting on the Structure
4.4.1 Construction load
4.4.2 Live load
4.4.3 Time History Load
4.5 Working of Shuttle Looms
4.5.1 Primary Motion
4.5.2 Secondary Motion
4.5.3 Ancillary Motion
4.6 Source of Vibration - The Beating-Up Motion
4.7 Codal Requirements
4.7.1 General requirements of Machine
4.7.1.1 General
4.7.1.2 Static Design
4.7.1.3 Dynamic Design
4.7.2 Design Criteria
4.8 Various Types of Remedial Techniques
4.8.1 Cross-Bracing
4.8.2 Jacketing of Columns
4.8.3 Tie-Beams
4.8.4 Haunches

Chapter: 5 Numerical Study and Results of Dynamic Analysis for an Industrial Building
5.1 General
5.2 Building Geometry
5.2.1 Ground Storey Building
5.2.2 Ground + One Storey Building
5.2.3 Ground + Two Storey Building
5.2.4 Loads acting on the Structure
5.3 Typical Input Data Required
5.3.1 Building Geometry
5.3.2 Material Data
5.3.3 Machine Data
5.3.4 Loads acting on the Structure
5.4 Expected Output Results
5.5 Typical Steps of defining Numerical Problem in STAAD.Pro
5.6 Numerical Study Problem
5.6.1 Building Geometry
5.6.2 Material Data
5.6.3 Shuttle Loom Machine Data
5.6.4 Loads Acting on the Structure
5.7 Numerical Study on Remedial Measures

Chapter: 6 Discussion and Conclusion
6.1 Concluding Remarks for Ground Storey Building
6.2 Concluding Remarks for Ground + One Storey
6.3 Concluding Remarks for Ground + Two Storey
6.4 Concluding Remarks on Remedial Measure of Ground Storey Building
6.5 Concluding Remarks on Remedial Measure of Ground + One Storey Building
6.6 Concluding Remarks on Remedial Measure of Ground + Two Storey Building

APPENDIX - I

APPENDIX - II

List of Figures

Figure Description

Fig. 1.1 Plain Power Loom

Fig. 1.2 Traditional Shuttle Loom

Fig. 1.3 Power Looms Machine

Fig. 1.4 Shuttle Looms Machine

Fig. 1.5 Typical Shuttle Looms Machine

Fig. 4.1 Modes of Vibration of Rigid Block Foundation

Fig. 4.2 Deformation Response Factor Vs Frequency Ratio

Fig. 4.3 Rotating Machine Diagram

Fig. 4.4 Reciprocating Machine Diagram

Fig. 4.5 Block Type Foundation

Fig. 4.6 Combined Block-type Foundation

Fig. 4.7 Pile Foundation

Fig. 4.8 Wall Type Foundation

Fig. 4.9 Framed-type Foundation

Fig. 4.10 Mechanism of Beating-up Motion

Fig. 4.11 Typical View of Cross-Bracing

Fig. 4.12 Various types of Bracing system

Fig. 4.13 Typical view of Jacketing of Column

Fig. 4.14 Typical view of Cross Tie beam

Fig. 4.15 Typical view of Haunch at Beam-Column junction

Fig. 5.1 Typical Floor Plan of Looms Industry and its Front Elevation

Fig. 5.2 Front Elevation of Looms Industry

Fig. 5.3 Typical Floor Plan of Looms Industry of Ground Floor and First Floor

Fig. 5.4 Front Elevation of Looms Industry for Ground + One Storey

Fig. 5.5 Typical Floor Plan of Looms Industry of Ground Floor ,First Floor and Second Floor

Fig. 5.6 Construction of Initial Frame

Fig. 5.7 Incorporating a Translation Repeat

Fig. 5.8 View of the Repeated Frame

Fig. 5.9 Labeling of the Structure

Fig. 5.10 Generating a four-noded plate for Slab element

Fig. 5.11 Generating a surface mesh for the Slab element

Fig. 5.12 Repeating the surface mesh for all other Slab

Fig. 5.13 Generation of the model for machine using a Beam element

Fig. 5.14 Repetition of the same at the actual machine location

Fig. 5.15 Assign the fixed support at the end

Fig. 5.16 3D-View of the entire structure along with support condition

Fig. 5.17 Assigning the thickness property to all the Slab element

Fig. 5.18 Assigning the geometrical property to the Beam

Fig. 5.19 Assigning the geometrical property to the Column

Fig. 5.20 Assigning the geometrical property to the Machine model

Fig. 5.21 Assigning the various Loads to the structural members

Fig. 5.22 Assigning the Analysis Command

Fig. 5.23 3D-View Building with Remedial Measures

Part - 1: Study on Dynamic Performance of Industrial Building Section A: Figure of Ground Storey Building

Fig. 5.24 Typical Modes Shapes of the Building Unit

Fig. 5.25 Effect of Beam Size and Storey Height on Horizontal Frequency and Horizontal Displacement (For Column Size 230 mm x 460 mm)

Fig. 5.26 Effect of Beam Size and Storey Height on Horizontal Frequency and Horizontal Displacement (For Column Size 230 mm x 540 mm)

Fig. 5.27 Effect of Beam Size and Storey Height on Horizontal Frequency and Horizontal Displacement (For Column Size 230 mm x 610 mm)

Fig. 5.28 Effect of Beam Size and Storey Height on Horizontal Frequency and Horizontal Displacement (For Column Size 230 mm x 685 mm)

Fig. 5.29 Effect of Beam Size and Storey Height on Horizontal Frequency and Horizontal Displacement (For Column Size 230 mm x 765 mm)

Fig. 5.30 Effect of Beam Size and Storey Height on Horizontal Frequency and Horizontal Displacement (For Beam Size 230 mm x 460 mm)

Fig. 5.31 Effect of Beam Size and Storey Height on Horizontal Frequency and Horizontal Displacement (For Beam Size 230 mm x 540 mm)

Fig. 5.32 Effect of Beam Size and Storey Height on Horizontal Frequency and Horizontal Displacement (For Beam Size 230 mm x 610 mm)

Fig. 5.33 Effect of Beam Size and Storey Height on Horizontal Frequency and Horizontal Displacement (For Beam Size 230 mm x 685 mm)

Fig. 5.34 Effect of Beam Size and Storey Height on Horizontal Frequency and Horizontal Displacement (For Beam Size 230 mm x 765 mm)

Section B: Table of Ground + One Storey Building

Fig. 5.35 Typical Modes Shapes of the Building Unit for Ground + One Storey

Fig. 5.36 Effect of Beam Size and Storey Height on Horizontal Frequency and Horizontal Displacement (For Column Size 230 mm x 460 mm)

Fig. 5.37 Effect of Beam Size and Storey Height on Horizontal Frequency and Horizontal Displacement (For Column Size 230 mm x 540 mm)

Fig. 5.38 Effect of Beam Size and Storey Height on Horizontal Frequency and Horizontal Displacement (For Column Size 230 mm x 610 mm)

Fig. 5.39 Effect of Beam Size and Storey Height on Horizontal Frequency and Horizontal Displacement (For Column Size 230 mm x 685 mm)

Fig. 5.40 Effect of Beam Size and Storey Height on Horizontal Frequency and Horizontal Displacement (For Column Size 230 mm x 765 mm)

Fig. 5.41 Effect of Beam Size and Storey Height on Horizontal Frequency and Horizontal Displacement (For Beam Size 230 mm x 460 mm)

Fig. 5.42 Effect of Beam Size and Storey Height on Horizontal Frequency and Horizontal Displacement (For Beam Size 230 mm x 540 mm)

Fig. 5.43 Effect of Beam Size and Storey Height on Horizontal Frequency and Horizontal Displacement (For Beam Size 230 mm x 610 mm)

Fig. 5.44 Effect of Beam Size and Storey Height on Horizontal Frequency and Horizontal Displacement (For Beam Size 230 mm x 685 mm)

Fig. 5.45 Effect of Beam Size and Storey Height on Horizontal Frequency and Horizontal Displacement (For Beam Size 230 mm x 765 mm)

Section C: Table of Ground + Two Storey Building

Fig. 5.46 Typical Modes Shapes of the Building Unit for Ground + Two Storey

Fig. 5.47 Effect of Beam Size and Storey Height on Horizontal Frequency and Horizontal Displacement (For Column Size 230 mm x 460 mm)

Fig. 5.48 Effect of Beam Size and Storey Height on Horizontal Frequency and Horizontal Displacement (For Column Size 230 mm x 540 mm)

Fig. 5.49 Effect of Beam Size and Storey Height on Horizontal Frequency and Horizontal Displacement (For Column Size 230 mm x 610 mm)

Fig. 5.50 Effect of Beam Size and Storey Height on Horizontal Frequency and Horizontal Displacement (For Column Size 230 mm x 685 mm)

Fig. 5.51 Effect of Beam Size and Storey Height on Horizontal Frequency and Horizontal Displacement (For Column Size 230 mm x 765 mm)

Fig. 5.52 Effect of Beam Size and Storey Height on Horizontal Frequency and Horizontal Displacement (For Beam Size 230 mm x 460 mm)

Fig. 5.53 Effect of Beam Size and Storey Height on Horizontal Frequency and Horizontal Displacement (For Beam Size 230 mm x 540 mm)

Fig. 5.54 Effect of Beam Size and Storey Height on Horizontal Frequency and Horizontal Displacement (For Beam Size 230 mm x 610 mm)

Fig. 5.55 Effect of Beam Size and Storey Height on Horizontal Frequency and Horizontal Displacement (For Beam Size 230 mm x 685 mm)

Fig. 5.56 Effect of Beam Size and Storey Height on Horizontal Frequency and Horizontal Displacement (For Beam Size 230 mm x 765 mm)

Part - 2: Study on Remedial Measures to improve the Performance of Industrial Building Subjected to Dynamic Loading

Section A: Figure of Remedial Measures for Ground Storey Building

CASE A: Strong Beam (230 mm x 685 mm) - Weak Column (230 mm x 460 mm)

Fig. 5.57 3D- View of Factory Building along with different Remedial Measures for Ground Storey Building

Fig. 5.58 Horizontal Frequency Vs Mode Shapes for Model Types 1 and 2

Fig. 5.59 Comparison of Horizontal Displacement for Model Types 1 and 2

Fig. 5.60 Horizontal Frequency Vs Mode Shapes for Model Types 1 and 3

Fig. 5.61 Comparison of Horizontal Displacement for Model Types 1 and 3

Fig. 5.62 Horizontal Frequency Vs Mode Shapes for Model Types 1 and 4

Fig. 5.63 Comparison of Horizontal Displacement for Model Types 1 and 4

Fig. 5.64 Horizontal Frequency Vs Mode Shapes for Model Types 1 and 5

Fig. 5.65 Comparison of Horizontal Displacement for Model Types 1 and 5

Fig. 5.66 Horizontal Frequency Vs Mode Shapes for Model Types 1 and 6

Fig. 5.67 Comparison of Horizontal Displacement for Model Types 1 and 6

CASE B: Strong Column (230 mm x 685 mm) - Weak Beam (230 mm x 460 mm)

Fig. 5.68 Horizontal Frequency Vs Mode Shapes for Model Types 1 and 2

Fig. 5.69 Comparison of Horizontal Displacement for Model Types 1 and 2

Fig. 5.70 Horizontal Frequency Vs Mode Shapes for Model Types 1 and 3

Fig. 5.71 Comparison of Horizontal Displacement for Model Types 1 and 3

Fig. 5.72 Horizontal Frequency Vs Mode Shapes for Model Types 1 and 4

Fig. 5.73 Comparison of Horizontal Displacement for Model Types 1 and 4

Fig. 5.74 Horizontal Frequency Vs Mode Shapes for Model Types 1 and 5

Fig. 5.75 Comparison of Horizontal Displacement for Model Types 1 and 5

Fig. 5.76 Horizontal Frequency Vs Mode Shapes for Model Types 1 and 6

Fig. 5.77 Comparison of Horizontal Displacement for Model Types 1 and 6

Section B: Table of Remedial Measures for Ground + One Storey Building

CASE A: Strong Beam (230 mm x 685 mm) - Weak Column (230 mm x 460 mm)

Fig. 5.78 3D- View of Factory Building along with different Remedial Measures for Ground + One Storey Building

Fig. 5.79 Horizontal Frequency Vs Mode Shapes for Model Types 1 and 2

Fig. 5.80 Comparison of Horizontal Displacement for Model Types 1 and 2

Fig. 5.81 Horizontal Frequency Vs Mode Shapes for Model Types 1 and 3

Fig. 5.82 Comparison of Horizontal Displacement for Model Types 1 and 3

Fig. 5.83 Horizontal Frequency Vs Mode Shapes for Model Types 1 and 4

Fig. 5.84 Comparison of Horizontal Displacement for Model Types 1 and 4

Fig. 5.85 Horizontal Frequency Vs Mode Shapes for Model Types 1 and 5

Fig. 5.86 Comparison of Horizontal Displacement for Model Types 1 and 5

Fig. 5.87 Horizontal Frequency Vs Mode Shapes for Model Types 1 and 6

Fig. 5.88 Comparison of Horizontal Displacement for Model Types 1 and 6

CASE B: Strong Column (230 mm x 685 mm) - Weak Beam (230 mm x 460 mm)

Fig. 5.89 Horizontal Frequency Vs Mode Shapes for Model Types 1 and 2

Fig. 5.90 Comparison of Horizontal Displacement for Model Types 1 and 2

Fig. 5.91 Horizontal Frequency Vs Mode Shapes for Model Types 1 and 3

Fig. 5.92 Comparison of Horizontal Displacement for Model Types 1 and 3

Fig. 5.93 Horizontal Frequency Vs Mode Shapes for Model Types 1 and 4

Fig. 5.94 Comparison of Horizontal Displacement for Model Types 1 and 4

Fig. 5.95 Horizontal Frequency Vs Mode Shapes for Model Types 1 and 5

Fig. 5.96 Comparison of Horizontal Displacement for Model Types 1 and 5

Fig. 5.97 Horizontal Frequency Vs Mode Shapes for Model Types 1 and 6

Fig. 5.98 Comparison of Horizontal Displacement for Model Types 1 and 6

Section C: Table of Remedial Measures for Ground + Two Storey Building

CASE 1: Strong Beam (230mm x 610mm) - Weak Column (230mm x 540mm)

Fig. 5.99 3D- View of Factory Building along with different Remedial Measures for Ground + Two Storey Building

Fig. 5.100 Horizontal Frequency Vs Mode Shapes for Model Types 1 and 2

Fig. 5.101 Comparison of Horizontal Displacement for Model Types 1 and 2

Fig. 5.102 Horizontal Frequency Vs Mode Shapes for Model Types 1 and 3

Fig. 5.103 Comparison of Horizontal Displacement for Model Types 1 and 3

Fig. 5.104 Horizontal Frequency Vs Mode Shapes for Model Types 1 and 4

Fig. 5.105 Comparison of Horizontal Displacement for Model Types 1 and 4

Fig. 5.106 Horizontal Frequency Vs Mode Shapes for Model Types 1 and 5

Fig. 5.107 Comparison of Horizontal Displacement for Model Types 1 and 5

Fig. 5.108 Horizontal Frequency Vs Mode Shapes for Model Types 1 and 6

Fig. 5.109 Comparison of Horizontal Displacement for Model Types 1 and 6

CASE 2: Strong Column (230mm x 610mm) - Weak Beam (230mm x 540mm)

Fig. 5.110 Horizontal Frequency Vs Mode Shapes for Model Types 1 and 2

Fig. 5.111 Comparison of Horizontal Displacement for Model Types 1 and 2

Fig. 5.112 Horizontal Frequency Vs Mode Shapes for Model Types 1 and 3

Fig. 5.113 Comparison of Horizontal Displacement for Model Types 1 and 3

Fig. 5.114 Horizontal Frequency Vs Mode Shapes for Model Types 1 and 4

Fig. 5.115 Comparison of Horizontal Displacement for Model Types 1 and 4

Fig. 5.116 Horizontal Frequency Vs Mode Shapes for Model Types 1 and 5

Fig. 5.117 Comparison of Horizontal Displacement for Model Types 1 and 5

Fig. 5.118 Horizontal Frequency Vs Mode Shapes for Model Types 1 and 6

Fig. 5.119 Comparison of Horizontal Displacement for Model Types 1 and 6

Note: All figures and graphs if not indicated otherwise, are protected by copyright owned by the authors

List of Table

Table Description

Table 5.1 A Building Unit having various Parameters and their Sizes for Ground

Table 5.2 A Building Unit having various Parameters and their Sizes for Ground + One Storey

Table 5.3 A Building Unit having various Parameters and their Sizes for Ground + Two Storey

Part - 1: Study on Dynamic Performance of Industrial Building

Section A: List of Tables for Ground Storey Building

Table 5.4 Effect of Beam Size and Storey Height on Horizontal Frequency in Z - Direction (For Column size 230 mm x 460 mm)

Table 5.5 Effect of Beam Size and Storey Height on Horizontal Displacement in Z - Direction (For Column Size 230 mm x 460 mm)

Table 5.6 Effect of Beam Size and Storey Height on Horizontal Frequency in Z - Direction (For Column Size 230 mm x 540 mm)

Table 5.7 Effect of Beam Size and Storey Height on Horizontal Displacement in Z - Direction (For Column Size 230 mm x 540 mm)

Table 5.8 Effect of Beam Size and Storey Height on Horizontal Frequency in Z - Direction (For Column Size 230 mm x 610 mm)

Table 5.9 Effect of Beam Size and Storey Height on Horizontal Displacement in Z - Direction (For Column Size 230 mm x 610 mm)

Table 5.10 Effect of Beam Size and Storey Height on Horizontal Frequency in Z - Direction (For Column Size 230 mm x 685 mm)

Table 5.11 Effect of Beam Size and Storey Height on Horizontal Displacement in Z - Direction (For Column Size 230 mm x 685 mm)

Table 5.12 Effect of Beam Size and Storey Height on Horizontal Frequency in Z - Direction (For Column Size 230 mm x 765 mm)

Table 5.13 Effect of Beam Size and Storey Height on Horizontal Displacement in Z - Direction (For Column Size 230 mm x 765 mm)

Table 5.14 Effect of Column Size and Storey Height on Horizontal Frequency in Z -Direction (For Beam Size 230 mm x 460 mm)

Table 5.15 Effect of Column Size and Storey Height on Horizontal Displacement in Z -Direction (For Beam Size 230 mm x 460 mm)

Table 5.16 Effect of Column Size and Storey Height on Horizontal Frequency in Z -Direction (For Beam Size 230 mm x 540 mm)

Table 5.17 Effect of Column Size and Storey Height on Horizontal Displacement in Z -Direction (For Beam Size 230 mm x 540 mm)

Table 5.18 Effect of Column Size and Storey Height on Horizontal Frequency in Z -Direction (For Beam Size 230 mm x 610 mm)

Table 5.19 Effect of Column Size and Storey Height on Horizontal Displacement in Z -Direction (For Beam Size 230 mm x 610 mm)

Table 5.20 Effect of Column Size and Storey Height on Horizontal Frequency in Z -Direction (For Beam Size 230 mm x 685 mm)

Table 5.21 Effect of Column Size and Storey Height on Horizontal Displacement in Z-Direction (For Beam Size 230 mm x 685 mm)

Table 5.22 Effect of Column Size and Storey Height on Horizontal Frequency in Z -Direction (For Beam Size 230 mm x 765 mm)

Table 5.23 Effect of Column Size and Storey Height on Horizontal Displacement in Z-Direction (For Beam Size 230 mm x 765 mm)

Section B: List of Tables for Ground + One Storey Building

Table 5.24 Effect of Column Size and Storey Height on Horizontal Frequency in Z -Direction (For Beam Size 230 mm x 460 mm)

Table 5.25 Effect of Column Size and Storey Height on Horizontal Displacement in Z -Direction (For Beam Size 230 mm x 460 mm)

Table 5.26 Effect of Column Size and Storey Height on Horizontal Frequency in Z -Direction (For Beam Size 230 mm x 540 mm)

Table 5.27 Effect of Column Size and Storey Height on Horizontal Displacement in Z -Direction (For Beam Size 230 mm x 540 mm)

Table 5.28 Effect of Column Size and Storey Height on Horizontal Frequency in Z -Direction (For Beam Size 230 mm x 610 mm)

Table 5.29 Effect of Column Size and Storey Height on Horizontal Displacement in Z -Direction (For Beam Size 230 mm x 610 mm)

Table 5.30 Effect of Column Size and Storey Height on Horizontal Frequency in Z -Direction (For Beam Size 230 mm x 685 mm)

Table 5.31 Effect of Column Size and Storey Height on Horizontal Displacement in Z-Direction (For Beam Size 230 mm x 685 mm)

Table 5.32 Effect of Column Size and Storey Height on Horizontal Frequency in Z -Direction (For Beam Size 230 mm x 765 mm)

Table 5.33 Effect of Column Size and Storey Height on Horizontal Displacement in Z-Direction (For Beam Size 230 mm x 765 mm)

Table 5.34 Effect of Beam Size and Storey Height on Horizontal Frequency in Z - Direction (For Column size 230 mm x 460 mm)

Table 5.35 Effect of Beam Size and Storey Height on Horizontal Displacement in Z - Direction (For Column Size 230 mm x 460 mm)

Table 5.36 Effect of Beam Size and Storey Height on Horizontal Frequency in Z - Direction (For Column Size 230 mm x 540 mm)

Table 5.37 Effect of Beam Size and Storey Height on Horizontal Displacement in Z - Direction (For Column Size 230 mm x 540 mm)

Table 5.38 Effect of Beam Size and Storey Height on Horizontal Frequency in Z - Direction (For Column Size 230 mm x 610 mm)

Table 5.39 Effect of Beam Size and Storey Height on Horizontal Displacement in Z - Direction (For Column Size 230 mm x 610 mm)

Table 5.40 Effect of Beam Size and Storey Height on Horizontal Frequency in Z - Direction (For Column Size 230 mm x 685 mm)

Table 5.41 Effect of Beam Size and Storey Height on Horizontal Displacement in Z - Direction (For Column Size 230 mm x 685 mm)

Table 5.42 Effect of Beam Size and Storey Height on Horizontal Frequency in Z - Direction (For Column Size 230 mm x 765 mm)

Table 5.43 Effect of Beam Size and Storey Height on Horizontal Displacement in Z - Direction (For Column Size 230 mm x 765 mm)

Section C: List of Tables for Ground + Two Storey Building

Table 5.44 Effect of Column Size and Storey Height on Horizontal Frequency in Z -Direction (For Beam Size 230 mm x 460 mm)

Table 5.45 Effect of Column Size and Storey Height on Horizontal Displacement in Z -Direction (For Beam Size 230 mm x 460 mm)

Table 5.46 Effect of Column Size and Storey Height on Horizontal Frequency in Z -Direction (For Beam Size 230 mm x 540 mm)

Table 5.47 Effect of Column Size and Storey Height on Horizontal Displacement in Z -Direction (For Beam Size 230 mm x 540 mm)

Table 5.48 Effect of Column Size and Storey Height on Horizontal Frequency in Z -Direction (For Beam Size 230 mm x 610 mm)

Table 5.49 Effect of Column Size and Storey Height on Horizontal Displacement in Z -Direction (For Beam Size 230 mm x 610 mm)

Table 5.50 Effect of Column Size and Storey Height on Horizontal Frequency in Z -Direction (For Beam Size 230 mm x 685 mm)

Table 5.51 Effect of Column Size and Storey Height on Horizontal Displacement in Z-Direction (For Beam Size 230 mm x 685 mm)

Table 5.52 Effect of Column Size and Storey Height on Horizontal Frequency in Z -Direction (For Beam Size 230 mm x 765 mm)

Table 5.53 Effect of Column Size and Storey Height on Horizontal Displacement in Z-Direction (For Beam Size 230 mm x 765 mm)

Table 5.54 Effect of Beam Size and Storey Height on Horizontal Frequency in Z - Direction (For Column size 230 mm x 460 mm)

Table 5.55 Effect of Beam Size and Storey Height on Horizontal Displacement in Z - Direction (For Column Size 230 mm x 460 mm)

Table 5.56 Effect of Beam Size and Storey Height on Horizontal Frequency in Z - Direction (For Column Size 230 mm x 540 mm)

Table 5.57 Effect of Beam Size and Storey Height on Horizontal Displacement in Z - Direction (For Column Size 230 mm x 540 mm)

Table 5.58 Effect of Beam Size and Storey Height on Horizontal Frequency in Z - Direction (For Column Size 230 mm x 610 mm)

Table 5.59 Effect of Beam Size and Storey Height on Horizontal Displacement in Z - Direction (For Column Size 230 mm x 610 mm)

Table 5.60 Effect of Beam Size and Storey Height on Horizontal Frequency in Z - Direction (For Column Size 230 mm x 685 mm)

Table 5.61 Effect of Beam Size and Storey Height on Horizontal Displacement in Z - Direction (For Column Size 230 mm x 685 mm)

Table 5.62 Effect of Beam Size and Storey Height on Horizontal Frequency in Z - Direction (For Column Size 230 mm x 765 mm)

Table 5.63 Effect of Beam Size and Storey Height on Horizontal Displacement in Z - Direction (For Column Size 230 mm x 765 mm)

Part - 2: Study on Remedial Measures to improve the Performance of Industrial Building Subjected to Dynamic Loading

Section A: Table of Remedial Measures for Ground Storey Building

CASE A: Strong Beam (230 mm x 685 mm) - Weak Column (230 mm x 460 mm)

Table 5.64 Effect of Cross-Bracing below Plinth Level on Horizontal Frequency and Displacement in Z-Direction (For Beam Size 230 mm x 685 mm - Column Size 230 mm x 460 mm) Table 5.65 Effect of Full Length Jacketing of Columns on Horizontal Frequency and Displacement in Z-Direction (For Beam Size 230 mm x 685 mm - Column Size 230 mm x 460 mm)

Table 5.66 Effect of Partial Jacketing of Columns above Plinth Level on Horizontal Frequency and Displacement in Z-Direction (For Beam Size 230 mm x 685 mm -Column Size 230 mm x 460 mm)

Table 5.67 Effect of Cross Tie-Beam on Horizontal Frequency and Displacement in Z-direction (For Beam Size 230 mm x 685 mm -Column Size 230 mm x 460 mm)

Table 5.68 Effect of Haunch on Horizontal Frequency and Displacement in Z- direction (For Beam Size 230 mm x 685 mm -Column Size 230 mm x 460 mm) CASE B: Strong Column (230 mm x 685 mm) - Weak Beam (230 mm x 460 mm)

Table 5.69 Effect of Cross-Bracing below Plinth Level on Horizontal Frequency and Displacement in Z-Direction (For Column Size 230 mm x 685 mm -Beam Size 230 mm x 460 mm)

Table 5.70 Effect of Full Length Jacketing of Columns on Horizontal Frequency and Displacement in Z-Direction (For Column Size 230 mm x 685 mm -Beam Size 230 mm x 460 mm)

Table 5.71 Effect of Partial Jacketing of Columns above Plinth Level on Horizontal Frequency and Displacement in Z-Direction (For Column Size 230 mm x 685 mm -Beam Size 230 mm x 460 mm)

Table 5.72 Effect of Cross Tie-Beam on Horizontal Frequency and Displacement in Z-direction (For Column Size 230 mm x 685 mm -Beam Size 230 mm x 460 mm)

Table 5.73 Effect of Haunch on Horizontal Frequency and Displacement in Z- direction (For Column Size 230 mm x 685 mm -Beam Size 230 mm x 460 mm)

Section B: Table of Remedial Measures for Ground + One Storey Building

CASE A: Strong Beam (230 mm x 685 mm) - Weak Column (230 mm x 460 mm)

Table 5.74 Effect of Cross-Bracing below Plinth Level on Horizontal Frequency and Displacement in Z-Direction (For Beam Size 230 mm x 685 mm - Column Size 230 mm x 460 mm)

Table 5.75 Effect of Full Length Jacketing of Columns on Horizontal Frequency and Displacement in Z-Direction (For Beam Size 230 mm x 685 mm -Column Size 230 mm x 460 mm)

Table 5.76 Effect of Partial Jacketing of Columns above Plinth Level on Horizontal Frequency and Displacement in Z-Direction (For Beam Size 230 mm x 685 mm -Column Size 230 mm x 460 mm)

Table 5.77 Effect of Cross Tie-Beam on Horizontal Frequency and Displacement in Z-direction (For Beam Size 230 mm x 685 mm -Column Size 230 mm x 460 mm)

Table 5.78 Effect of Haunch on Horizontal Frequency and Displacement in Z- direction (For Beam Size 230 mm x 685 mm -Column Size 230 mm x 460 mm)

CASE B: Strong Column (230 mm x 685 mm) - Weak Beam (230 mm x 460 mm)

Table 5.79 Effect of Cross-Bracing below Plinth Level on Horizontal Frequency and Displacement in Z-Direction (For Column Size 230 mm x 685 mm -Beam Size 230 mm x 460 mm)

Table 5.80 Effect of Full Length Jacketing of Columns on Horizontal Frequency and Displacement in Z-Direction (For Column Size 230 mm x 685 mm -Beam Size 230 mm x 460 mm)

Table 5.81 Effect of Partial Jacketing of Columns above Plinth Level on Horizontal Frequency and Displacement in Z-Direction (For Column Size 230 mm x 685 mm -Beam Size 230 mm x 460 mm)

Table 5.82 Effect of Cross Tie-Beam on Horizontal Frequency and Displacement in Z-direction (For Column Size 230 mm x 685 mm -Beam Size 230 mm x 460 mm)

Table 5.83 Effect of Haunch on Horizontal Frequency and Displacement in Z- direction (For Column Size 230 mm x 685 mm -Beam Size 230 mm x 460 mm)

Section C: Table of Remedial Measures for Ground + Two Storey Building

CASE 1: Strong Beam (230mm x 610mm) - Weak Column (230mm x 540mm)

Table 5.84 Effect of Cross-Bracing below Plinth Level on Horizontal Frequency and Displacement in Z-Direction (Beam 230mm x 610mm - Column 230mm x 540mm)

Table 5.85 Effect of Full Length Jacketing of Columns on Horizontal Frequency and Displacement in Z-Direction (Beam 230mm x 610mm - Column 230mm x 540mm)

Table 5.86 Effect of Partial Jacketing of Columns above Plinth Level on Horizontal Frequency and Displacement in Z-Direction (Beam 230mm x 610mm - Column 230mm x 540mm)

Table 5.87 Effect of Cross Tie-Beam on Horizontal Frequency and Displacement in Z-direction (Beam 230mm x 610mm - Column 230mm x 540mm)

Table 5.88 Effect of Haunch on Horizontal Frequency and Displacement in Z- direction (Beam 230mm x 610mm - Column 230mm x 540mm)

CASE 2: Strong Column (230mm x 610mm) - Weak Beam (230mm x 540mm)

Table 5.89 Effect of Cross-Bracing below Plinth Level on Horizontal Frequency and Displacement in Z-Direction (Column 230mm x 610mm - Weak Beam 230mm x 540mm)

Table 5.90 Effect of Full Length Jacketing of Columns on Horizontal Frequency and Displacement in Z-Direction (Column 230mm x 610mm - Weak Beam 230mm x 540mm)

Table 5.91 Effect of Partial Jacketing of Columns above Plinth Level on Horizontal Frequency and Displacement in Z-Direction (Column 230mm x 610mm - Weak Beam 230mm x 540mm)

Table 5.92 Effect of Cross Tie-Beam on Horizontal Frequency and Displacement in Z-direction (Column 230mm x 610mm - Weak Beam 230mm x 540mm)

Table 5.93 Effect of Haunch on Horizontal Frequency and Displacement in Z- direction (Column 230mm x 610mm - Weak Beam 230mm x 540mm)

Chapter1 Introduction

1.1 History of Textile

The history of spinning and weaving was discussed in an article published in the autumn 1951 issue of wool knowledge, and concluding sentence of that article read: “Despite the invention of greatly elaborated machinery, housed in vast mills, the basic principles of the machinery for spinning and weaving remain the same now as when Neolithic man first drew out the raw wool and twisted it into yarn between his fingers, and with it wove the first primitive woolen fabric. “ some qualification of that statement ought perhaps to be made, for in present day machinery the principles involved are the same only to the extent that the fundamentals of weaving are unalterable.

A woven structure requires the interlacing of one series of threads called “weft”, with another series of threads called “wrap”, the latter being set at right angles to the weft threads. Several hundred wrap threads must be delivered together so that the weft threads can pass across one at a time to interlace with the woven.

The means used on modern power-looms for delivering the wrap threads to the point where weft picks may be interlaced with them, for separating the wrap threads to produce the space or “shed” for the insertion of weft in a variety of interlacing, for projecting shuttles or otherwise inserting weft picks possibly in several colors and in various orders of coloring, for closing weft picks against cloth already woven and for moving the cloth forward on to a roller or beam as it is made, are vastly different in detail and sometimes even in principle from one make of power-loom to another. In addition, the modern power-loom has many extra mechanisms which are designed to save the operative time and effort, to improve the quality of the cloth produced and to prevent damage to the threads and to the various mechanisms if anything out of the normal occurs during weaving.

Dynamic Analysis of Structure for Looms Industry- A Parametric Study 1

illustration not visible in this excerpt

Fig. 1.1 Plain Power Loom

(Crown Copyright: the Science Museum, South Kensington)

1.2 History of Textile Industry in Surat City

The existence of the Industry in Surat dates back to 1925. During the Mogul reign on account of perfect trade policy the Kinkhab weavers of Surat were artisan themselves producing intricate designs on handlooms with silk and jari. At that time a large number of handlooms were functioning at this center and raw silk as well as jari threads were the main raw materials for manufacture of textiles. Gradually with the invention of electricity, young entrepreneurs engaged in this Industry converted handloom to power driven and later on installed the power looms discarded by the Cotton Mills commenced production after certain modifications so as to make them suitable for manufacturing pure silk fabrics and with this change over, the production increased rapidly, the quality improved significantly, physical labour and strains were reduced to some extent and ultimately resulted in higher earnings for the power loom weavers. In fact the Industry’s structure resembles to that of the Cottage Industry System prevalent in Japan. It was domestic Industry where there were 1,500 units and the members of the family usually maintained themselves by working on an average 8 power looms each. Thus the power looms were more or less being dispersed into small decentralized units.

Dynamic Analysis of Structure for Looms Industry- A Parametric Study 2

illustration not visible in this excerpt

Fig. 1.2 Traditional Shuttle Loom

(Crown Copyright: Toyota industries Corporation)

Between the years 1935-37 with the advent of protection offered to this Industry by way of heavy duty on import of Art Silk fabrics, the Power loom Industry gradually grew into a small nucleus with total installed capacity of 1,200 power looms in Surat and by the time the second world war broke out, the Industry was yet in its infant stage. Though after the war, the development of this industry has advanced slowly but steadily. In Surat the Industry has achieved a spectacular progress.

Today Surat and surrounding South Gujarat region is the biggest center of Art Silk Weaving Industry in India where more than 5,00,000 power loom are working producing about 600 Crores Mts. of cloth i.e. about l/3rd of the man made filament fabrics. This Industry has played a phenomenal role in the industrial development plans of the Textiles and it is beyond doubt that the self accomplished progress of the industry has attracted the attention of the ever changing world to this de-centralized industry at Surat. The city accounts for - “40% of the Nation’s total manmade fabric production.” - “28% Nation’s total manmade fiber production” - “18% of Nation’s total manmade fiber export” - “12% of the Nation’s total fabric products”

After the 2nd world war ended, in early fifties the entrepreneur-weavers installed Japanese machines for weaving, twisting etc. and started importing staple fiber spun and viscose filament yarn to manufacture art silk fabrics. Local machinery manufactures also started manufacturing psudakoma and Toyoda and Auru models of weaving and twisting machines suitable for weaving fine and superfine fabrics.

The decentralized Power Loom Sector plays an important role in Indian Textiles and Clothing Segment. However, time has already lapsed to the Power Loom Sector Industry to prepare itself to face the challenges on account of W.T.O. regime and also global competition. In-order to survive and expand its market share a thought process on modernization by installing most modern and sophisticated machineries especially automatic, semi automatic looms having bigger width Looms like 68" reed space and 72" reed space etc. by replacing the old ordinary Looms. It is a well known fact that INDIA have fully equipped in the preparatory capacities in producing the required raw materials up-to weaving stage. However, in the International market most of the countries around the world are demanding for the bigger width fabrics of 58" and 60" etc. But due to lack of these bigger width weaving machines and insufficient capacity and capability. Textile manufacturers are not able to compete with other countries by offering defect free bigger width fabrics in the international market.

illustration not visible in this excerpt

Fig. 1.3 Power Looms Machine

(Crown Copyright: Arun Textile Engineers Pvt. Ltd.)

Dynamic Analysis of Structure for Looms Industry- A Parametric Study

Government of INDIA has already announced a comprehensive package namely TECHNOLOGY UPGRADATION FUND (TUF). The scheme has recently enlarged to the power Looms Units for modern machineries wherein subsidy portion has also been increased from 12% to 20%. Special advantages offered by the Government have to be undertaken and by way of this, Global competition in the Textile Sector can be met to a great extent.

As indicated above, SURAT’S Textile Sector Industries have fully equipped with most modern and sophisticated preparatory capacities to produce high twisted varieties like Georgette, Chiffons, Chirmins, Wrinkle Fabrics and varieties having special effects in fall and wrap of fabrics on account of high twist. In the recent past years a huge number of Two-for-one twisters were installed in the Textile Sector especially at Surat region which has substantially enhanced the preparatory capacity to the Weaving Sector Industries. This high speed operating modern machines challenges the job of Structural Engineers, in providing the adequate design of a building so as to withstand the Dynamic Load imparted by Machines.

In INDIA, Surat is the major center in producing 100% Polyester Filament based fabrics. In this segment a large number of value added varieties are also being produced like Embroidery fabrics, Burnout Brasso varieties, Butta effect fabrics, Embossed designs, pleating designs, rubber printing and hand printed varieties and also made up articles like Scarves, Parios etc.

illustration not visible in this excerpt

Fig.1.4 Shuttle Looms Machine

Dynamic Analysis of Structure for Looms Industry- A Parametric Study

In the recent days, it is observed that there is a good demand for the Embroidered Fabrics from different parts of the World. Surat region exporters were able to accommodate all these sudden demands of Embroidery fabrics because since last two years a large numbers of Imported most modern Embroidery Machineries were also installed in Surat region.

All these installed capacities of Embroidery activities are running with a 90% efficiency so as to accommodate the demands from the International markets. There would be a good scope for the Embroidery fabrics on the export front hence focus has been laid upon the production of new designs and patent in the Embroidery Sector.

These looms machines have transformed the entire scenario of Textile production. It enables easy and faster production rate of textile manufacturing. These machines have proved to be a boom to Textile manufacturers in terms of economy and time. However, these machines come with an unseen drawback of “Vibrations” due to that high operating speed.

These serious problems of vibrations drew attention of the technocrats. Hence forth an initiative has been taken to execute - “Dynamic Analysis of Structures for Looms Industry”.

1.3 Problem Definition

Vibration can be defined as regularly and repeated movement of a physical object about a fixed point. The parameter normally used to assess the vibration is the resonance, frequency, amplitude etc. In order to completely define a vibration, the amplitude and frequency of motion are measured in three orthogonal directions, generally in terms of velocity which is considered to be the best description for assessing the potential damage response of a structure. There are many sources of vibration capable of producing motion sufficient to be perceptible by the occupants of the building. Various sources of vibrations are:

- External Sources
- Seismic activity
- Subway, road and rail systems o Industrial works
- Construction equipments

Dynamic Analysis of Structure for Looms Industry- A Parametric Study 6

Acknowledgement

We would like to take this opportunity to express our profound debt of gratitude towards Jigar K. Sevalia, Assistant Professor in Civil Engineering Department, Sarvajanik College of Engineering and Technology, Surat, for his valuable guidance, helpful comments and cooperation with kind and encouraging attitude at all the stages of the work, without which this work could not have been completed.

We are highly thankful to Himanshu Padhya, Head of the Department, for his motivational comments and ideas.

We would like to thank Gaurang Parmar, Civil Engineering Department, Sarvajanik College of Engineering and Technology, Surat, Gujarat, for his valuable contribution towards the completion of this work.

We would also wish to thank Mr. Anil Shinde, Mechanical Engineer at Primeir Works, Udhana, Surat, for providing us the information about various machine parts and other details. We highly grateful to Mr. Dhanesh Rotliwala, owner of P.N.Textiles, Surat, for explaining us the general construction practices being incorporated in structures for looms industry. He also helped us in understanding the general arrangements of machine onto the industrial floor plan.

We would be failing in our duty if we do not acknowledge the help and assistance that we received from the entire Civil Engineering Department, Sarvajanik College of Engineering and Technology, Surat, which helped us in some or the other way for the successful completion of this work.

Abstract

Ever since the existence of mankind, it has noticed a remarkable advancement in field of science and technology. Traditional hand weaving methods have been replaced by modern and speedy looms machine. With faster production rate, these machines proved to be a boon for textile manufacturers. However, they come with an unnoticed problem of “ vibration ” . Hence, there arises a need to study the effects of vibrations on the structural as well as non structural components of the building.

Here in this project, an attempt has been made to study the dynamic behaviour of a structure for looms industry subjected to vibration due to operations of looms machine; by changing the size of various structural components like beam and column.

With an increase in demand of textile, more and more looms machines are being installed every day. While designing the structure to house these looms it becomes incumbent upon the designer to curtail the amplitude of vibrations within the permissible limits. He/She must also make sure that the frequency of structure is separated for operating frequency of machine by a good margin, so that the “ Resonance Condition ” can be avoided.

The looms machine fall under the category of reciprocating machine. These machines have medium operating speed ranging from 100 rpm to 180 rpm. The main source of vibration is the Beating-Up motion. This generates a Harmonic Load due to the unbalanced force caused by the reciprocating sley movement. Hence, the designing of structure for looms industry is a complex process which needs prime considerations.

The cost of dynamic analysis of these structure is paramount, hence a small fraction of amount is being spent might lead to inadequately constructed structures which may result in failure and shut downs, exceeding many times the cost of the capital investment required for properly designed and built structure.

Sometimes it happens that all the results satisfy codal requirements except one or two results. Now analysis of frame foundation consumes a lot of time as it is a very complex problem and hence we can ’ t go for one by one parameter and have a check on results. Also by varying parameter with judgment, it may happen that results are still far away from required level.

Now, in such a case by executing parametric study, one can decide which parameter out of many is most sensitive to odd results, so that by varying those parameters only results can be brought to the required level and do not affect other reliable results.

An attempt is made in the thesis to carry out a parametric study by using software STAAD. Pro

Following Parameters are studied in this thesis

1. Sizes of Column
2. Sizes of Beams
3. Storey Height
4. Number of Stories
5. Effect of remedial measures to avoid resonance conditions like:
1. Cross Bracing below Plinth Level
2. Full Length Jacketing of Columns
3. Partial Length Jacketing of Columns above Plinth Level
4. Cross Tie-Beams
5. Haunches at the Junctions of Columns and Beams

Details of Paper Published in International Journals

illustration not visible in this excerpt

- Internal Sources
- Elevator and conveyance system o Fluid pumping equipments o Exercise rooms

illustration not visible in this excerpt

Fig.1.5 Typical Shuttle Looms Machine

(Image Courtesy: Richard Marsden/Creative Commons)

The modern looms machines have transformed the entire scenario of Textile production. It enables easy and faster production rate of textile manufacturing. These machines have proved to be a boon to Textile manufacturers in terms of economy and time. However, they come with an unseen drawback of “Vibrations” due to their high operating speed. The parameters normally used to assess the vibration are the amplitude and frequency. In order to completely define a vibration, the amplitude and frequency of motion are measured in three orthogonal directions, generally in terms of displacement which is considered to be the best description for assessing the potential damage response of a structure. These vibrations may cause varying degree of damage to the building components. Minor damage is seen in the building to non-structural components such as cracking of masonry walls, de-bonding of aggregate and cement gel, etc. However, if the amplitude of vibration increases, it may cause serious damage to structural components such as excessive deformation of beams, columns, fatigue failure and settlements; which may cause serious damage to life and property. Vibration at a certain level can cause discomfort to humans. It can affect visual perception, muscles contraction, circulation and respiratory system. This deteriorates the working capacity of the people.

Dynamic Analysis of Structure for Looms Industry- A Parametric Study

Chapter 2 Aim of the Study

An attempt will be made to study in depth the effects of sizes of various structural components on dynamic parameters of the building like frequency, amplitude etc. After executing the parametric study of effect of various structural components of building on dynamic performance, general conclusions will be made.

Various parametric studies to be executed are as follows:-

- Effect of Column Size on Frequency and Amplitude.
- Effect of Beam Size on Frequency and Amplitude.
- Effect of Storey Height on Frequency and Amplitude.
- Effect of Number of Storey on Frequency and Amplitude. - Effect of Remedial Measure on Frequency and Amplitude:

1. Cross-Bracing below Plinth Level.
2. Full Length Jacketing on Columns.
3. Partial Length Jacketing on Columns above Plinth Level.
4. Building with Cross Tie-Beam at 3 m above Plinth Level.
5. Building with Haunches at 3 m above Plinth Level at Beam Column

Junction.

In this study, graphs of Horizontal Frequency in different Modes corresponding to various Structural sizes will be plotted. Further in order to draw the conclusion with ease, graphs of Horizontal Displacement would also be plotted, corresponding to respective structural sizes.

Chapter 3 Literature Review

The ACI Committee[[2]] presents various design criteria and methods and procedures of analysis, design, and construction currently applied to dynamic equipment foundations by industry practitioners. They also provide general guidance with reference materials, rather than specifying requirements for adequate design. It mentions multiple design methods and criteria in use, factors, which may influence the choice, are presented.

Anil K. Chopra[[3]] has explained in detail about the fundamental theory of vibration. He states that a simple structure can be idealized as a system with a lumped mass and a mass-less supporting structure, having a single-degree-of-freedom (SDF) system. These vibrations can either be free vibration or forced vibration depending on the type of force acting on the structure. He has also commented on the response of the SDF systems to harmonic excitation in structural dynamics, which will provide the insight into how the system will respond to various types of force acting on them.

Arya A. S.[[4]] suggested ferrocement as a repair and strengthening material for low rise building.

Barkan D. D.[[6]] has commented on the behaviour of reciprocating machines and the type of load it imparts to the foundation. He has proposed general directives for carrying out a dynamic analysis of a machine foundation. He has also given explained how the unbalanced inertial force imparts dynamic load to the structures.

Behruz Bagheri Azar and Mohammad Reza Bagerzadeh Karimi[[7]] have studied various kinds of bracing that are used in tall structures and the most effective bracing that can be employed in tall structures. Advantage of diagonal bracings is that the main beams have minimum participation in resisting of lateral loads.

Bhatia K.G.[[8]] has mentioned that in principle machine foundations should be designed such that the dynamic forces of machines are transmitted to the soil through the foundation in such a way that all kinds of harmful effects are eliminated. All machine foundations, irrespective of the size and type of machine, should be regarded as engineering problems and their designs should be based on sound engineering practices. Dynamic loads from the machines causing vibrations must be duly accounted for to provide a solution, which is technically sound and economical.

Bureau of Indian Standards, IS:2974 (Part I) - 1982 (Reaffirmed 1998)[[11]] covers the design and construction of foundations for machines of the reciprocating type which normally generate steady state vibration and is of a size for which a rigid block type foundation is normally used. It also aids in the guidelines that are necessary for the design and analysis of foundations for reciprocating machines.

The ideas about the characteristics of harmonic force stated by Cyril Harris[[16]] in his book “Harris’ Shock and Vibrations” were proved to be beneficial while making the mathematical model of the looms machine.

Deulkar W. N., Modhera C. D. & Patil H. S.[[17]] has incorporated the use of buckling restrained bracings which provides good control for the roof displacement as compared to the bare frame (frame with no braces). The frames with poor or insufficient stiffness can be retrofitted with addition of such bracing to control the roof displacements and resist the lateral loads. The Buckling Restrained Braces are also the reliable and practical alternative to enhance the earthquake resistance of existing and new structures

European Forum Reciprocating Compressors (EFRC)[[19]] describes procedures and guidelines for the measurement and classification of mechanical vibration of reciprocating systems. Without limitations, all these features can cause considerable vibration and cyclic stress levels in different parts of the system. The vibration levels of reciprocating machines are generally higher than for rotating compressors but, since they are largely determined by Dynamic Analysis of Structure for Looms Industry- A Parametric Study 10 the design features of the compressor they tend to remain more constant over the life of the compressors than for rotating compressors.

Fabreeka Corporation USA[[21]] states that in order to achieve acceptable amplitudes of vibration at the source or recipient, it becomes necessary to make the support structure independent (isolated) from the rest of the environment. This separation prevents vibration from being transmitted directly through the support structure. This will also avoid the resonance (amplification of vibration) in the building.

George Gazetas[[22]] has described that the basic goal in design of machine foundation is to limit its motion to amplitudes which will neither endanger the satisfactory operation of the machine nor will they disturb the people working in the immediate vicinity. Thus a key ingredient to a successful machine foundation design is the carful engineering analysis of the foundation response to the dynamic load from the anticipated operation of the machine.

Gopal L. Rai[[23]] has described various techniques for strengthening the RC Columns such as Concrete Jacketing, Steel Jacketing, FRP Wrapping, Precast Concrete Jacketing, External Pre-stressing. He has also described the advantages, disadvantages and suitability of the specific technique to a particular kind of work.

Handbook on Repair and Rehabilitation of R.C.C. Building [[24]], explains the distressing of concrete subjected to cyclic loads and temperatures. It also throws light on cracking pattern and stress propagation. Furthermore, it says that, the remedial measure, such as R.C.C. Jacketing, has an advantage of increasing the member stiffness and its usefulness in controlling deterioration as it increases the member size significantly. This technique is a better solution for avoiding buckling of R.C.C columns that are slender.

Hasmukhrai B.[[25]] has explained in detail about the principle of beating -up motion and the magnitude of force produced by movement of sley.

Dynamic Analysis of Structure for Looms Industry- A Parametric Study 11 Hjelmstad Keith D. and Foutch Douglas A.[[26]] has explained about the importance of Steel Bracing member in the structure, improves the behavior of the building under the earthquake forces. The repaired building has a greater stiffness and strength. Lateral Displacements and pounding against the adjacent building also reduces.

John P. Wolf and Andrew J. Deeks[[31]] in his book “Foundation Vibration Analysis: A Strength-of-Materials Approach” has described about the varied thinking of a Soil Engineer, who considers the super-structure as an idealized elastic block, or even as a uniform load applied to the ground and a Structural Engineer on the other hand represents the ground as a distributed bed of springs or as a rigid boundary. He further adds that the modeling of the superstructure should not be in 3-Dimensions but in to a collection of 2- Dimensions (shell or plate) which represents the “Strength of Material Approach” in this book.

Katsuki Takiguchi and Abdullah[[32]] has investigated that ferrocement has a great potential to be used as a strengthening jacket material for substandard reinforced concrete columns. The results of this investigation indicated that strengthening of a square reinforced concrete column with circular ferrocement jacket was considered to successful.

Lachal A. and Aribert J. M.[[33]] states about the possible solution to strengthen the beam column joints are by addition of haunch between beam and column. The provision of haunch ensures a better balance between hogging and sagging moment resistances in a composite connection.

Nurudeen A. Raji[[39]] has explained about the beat-up mechanism. His study includes impulse-momentum method for the analysis of the narrow loom with impulsive force and discontinuous velocities. The system equation of motion is analyzed to determine the main body velocities used for the system variables without introducing rotational coordinates or the turning effect of the system follower on the beater.

Rathish Kumar P. and Oshima T.[[43]] signifies the use of ferro-cement for retrofitting of the external confinement of columns which enhanced the stiffness, ductility, strength and energy dissipation capacity of columns. The mode of failure could be changed from brittle shear failure to ductile flexural failure. The axial loads influence the hysteretic response of columns and the energy absorption capacity. The effect of axial compression on column response was the acceleration of strength and stiffness degradation under repeated inelastic load cycles

Sen Huang [[48]] has provided a background to develop and demonstrate a structural modeling strategy that can accurately predict the steady-state dynamic behavior of a complex and realistic machinery structural assembly. Most of the structural dynamic analyses are carried out with the assumption of linearity in structure’s behavior, even though nonlinearity is the underlying actuality. Such an assumption can be justified on the ground that it produces acceptably accurate solutions and at the same time simplifies the model processing.

Snowden D. C.[[50]] in his book has explained about the working of Plain Power Loom. He has described the three main motions of the plain power loom which are Primary motion, Secondary motion and Ancillary (Auxiliary) motion. The primary motion comprises of take -up, shedding, picking and weft insertion. The secondary motion consists of the beating-up motion, warp-let off, etc. The ancillary motion consists of the warp-stop mechanism and weft stop mechanism which prevents the breakage of the material. It also provides refinement of primary and secondary motions.

Srinivasulu P. and Vaidyanathan C.V.[[51]] have explained the forces that are responsible for vibration caused during the working of a shuttle loom machine. This book also outlines about the general concepts and requirements of a machine foundation. This book also includes explanation of principles of planning, designing and construction of machine foundations illustrated with examples. This book states that the two principle sources of vibrations of a shuttle loom are: the inertial force created by reciprocating movement of sley and the force that propels the shuttle in form of impact.

Thevendran V. and Wang C. M.[[52]] have stated that the cross-bracing can also be used where there in non-symmetry in the structure. His paper presents a numerical method based on the energy principle for the determination of buckling load and effective length factor of the compression brace member.

Uang Chia-Ming and Noel Shane[[54]] states about the provision of providing welded haunches to the beam column joints which perform better than the reduced beam sections (RBS). The ductile behaviour observed was good under the cyclic load tests which were performed under the test setup. Welding a triangular haunch to the beam bottom flange significantly improved the cyclic performance.

Ungermann D and Strohmann I.[[55]] presents that with the use of haunches the stability of I-shaped members can be achieved. They have described certain design criteria which are useful in small scale construction where finite-element method is not employed in daily use.

Victor Wowk[[56]] has presented his ideas on deciding the strategy in analysing the vibrations produced by machines. His strategy of analysis includes: identifying source of vibration, calculating its frequency and amplitude and analyse the severity of this amplitude. The source of vibration was identified to be as the beating-up motion.

Vijay K. Puri and Shamsher Prakash[[57]] have stated that machine foundations require a special consideration because they transmit dynamic loads to soil in addition to static loads due to weight of foundation, machine and accessories. He has described about three types of machines which are reciprocating machines, Impact machines and Rotary machines. In this study, the Looms machine lies under the category of Reciprocating machine having operating speed less than 600 rpm.

Wachel J. C. and Tison J. D[[58]] states that whenever heavy vibrations are encountered due to the reciprocating machines it is necessary to determine the extent of vibration within the permissible limits. He has suggested the criteria to judge the acceptability of the vibrations along with troubleshooting methods to determine the problems caused by resonance condition.

Waghmare Pravin B.[[59]] has stated that Seismic protection of buildings is a needbased concept aimed to improve the performance of any structure under future earthquakes causing extensive damage to life and property. Some recently developed materials and techniques can play vital role in structural repairs, seismic strengthening and retrofitting of existing buildings, whether damaged or undamaged. The various repair techniques employed by him giving good and reliable results are confinement, jacketing, fiber reinforced polymer jacketing, steel jacketing, beam jacketing.

Chapter 4 Theoretical Background

4.1 Vibration theory

4.1.1 Definition

If the motion of the body is oscillating or reciprocating in character, it is called vibration if it involves deformation of the body. In case the reciprocating involves only the rigid body movement without its deformation, then it is called oscillation. e.g. Motion of a multi-storey building during earthquake is vibration as there is deformation of the building .

There are mainly two types of vibration:

1. Free Vibration: Free Vibrations occur under the influence of forces inherent in the system itself, space without any external forces. However, to start free vibration, some external force or natural disturbance is required.
2. Forced Vibration: Forced vibrations occur under the influence of external exciting force.

4.1.2 Types of loads

The loads coming on the structure are basically of two types:

1. Static Load

These are those loads whose magnitude and direction does not vary with change in time.

For example: Dead Loads, Impose Load on Furniture’s, Floor Finishing, Snow Load, etc.

2. Dynamic Load

These are those loads whose magnitude and direction vary with change in time.

For example: Wind Load, Moving Load, Machine Loads, Earthquake Loads, Impact and Blast Loads etc.

Static Dynamic

Prescribed Random

(Deterministic) (Probabilistic)

Periodic Non-Periodic

Harmonic Non-harmonic Transient Impulsive

4.1.3 Degrees of Freedom

A typical concrete block is regarded as rigid as compared to the soil over which it rests. Therefore, it may be assumed that it undergoes only rigid-body displacements and rotations. Under the action of unbalanced forces, the rigid block may thus undergo displacements and oscillations as follows (Fig.5)

1. Translation along Z axis
2. Translation along X axis
3. Translation along Y axis
4. Rotation about Z axis
5. Rotation about X axis
6. Rotation about Y axis

Any rigid-body displacement can be resolved into these six independent displacements. Hence, the rigid block has six degrees of freedom and six natural frequencies.

illustration not visible in this excerpt

Fig. 4.1 Modes of Vibration of a Rigid Block Foundation

(Crown Copyright: Journal of Structural Engineering, SERC, Madras)

Out of six types of motion, translation along the Z axis and rotation about the Z axis can occur independently of any other motion. However, translation about the X axis (or Y axis) and rotation about the Y axis (or X axis) are coupled motions. Therefore, in the analysis of a block, we have to concern ourselves with four types of motions.

Two motions are independent and two are coupled. For determination of the natural frequencies, in coupled modes, the natural frequencies of the system in pure translation and pure rocking need to be determined. Also, the states of stress below the block in all four modes of vibrations are quite different. Therefore, the corresponding soil-spring constants need to be defined before any analysis of the foundations can be undertaken.

4.1.4 Resonance

It is a condition when the frequency of the structures coincides with the operating frequency of the machine. During this condition, the displacement of Dynamic Analysis of Structure for Looms Industry- A Parametric Study the structure is observed to at its peak. Hence, the frequency of the structure should be kept 20% less or 20% more than the operating frequency of the machine.

The condition in which the frequency of structure is less than frequency of machine, the structure becomes under tuned and in under tuned condition the displacement increases with increase in frequency.

illustration not visible in this excerpt

Fig. 4.2 Deformation Response Factor Vs Frequency Ratio

The condition in which the frequency of structure is more than the frequency of machine, the structure becomes over tuned and in this condition the displacement decreases with increase in frequency of the structure. The structure becomes more rigid when over tuned condition is adopted. The over tuned condition imparts more stiffness which restricts the displacement. However, it must be noticed that the over tuned structure have greater cross sectional area which makes the uneconomical.

Dynamic Analysis of Structure for Looms Industry- A Parametric Study

4.2 Classification of Machines

4.2.1 Rotating machinery: This category includes gas turbines, steam turbines, and other expanders; turbo-pumps and compressors; fans; motors; and centrifuges. These machines are characterized by the rotating motion of impellers or rotors. Unbalanced forces in rotating machines are created when the mass Centroid of the rotating part does not coincide with the centre of rotation. This dynamic force is a function of the shaft mass, speed of rotation, and the magnitude of the offset.

illustration not visible in this excerpt

Fig. 4.3 Rotating Machine Diagram

(Crown Copyright: ACI Committee)

4.2.2 Reciprocating machinery: For reciprocating machinery, such as compressors and diesel engines, a piston moving in a cylinder interacts with a fluid through the kinematics of a slider crank mechanism driven by, or driving, a rotating crankshaft. Individual inertia forces from each cylinder and each throw are inherently unbalanced with dominant frequencies at one and two times the rotational frequency.

illustration not visible in this excerpt

Fig. 4.4 Reciprocating Machine Diagram

(Crown Copyright: ACI Committee)

Dynamic Analysis of Structure for Looms Industry- A Parametric Study

4.2.3 Impulsive machinery: Equipment, such as forging hammers and some metal-forming presses, operate with regulated impacts or shocks between different parts of the equipment. This shock loading is often transmitted to the foundation system of the equipment and is a factor in the design of the foundation.

4.3 Types of Foundations

4.3.1 Block-type foundation:

Dynamic machines are preferably located close to grade to minimize the elevation difference between the machine dynamic forces and the center of gravity of the machine-foundation system. The ability to use such a foundation primarily depends on the quality of near surface soils. The dynamic response of a rigid block foundation depends only on the dynamic load, foundation’s mass, dimensions, and soil characteristics.

illustration not visible in this excerpt

Fig. 4.5 Block-type foundation

(Crown Copyright: ACI Committee)

4.3.2 Combined block-type foundation:

Combined blocks are used to support closely spaced machines. Combined blocks are more difficult to design because of the combination of forces from two or more machines and because of a possible lack of stiffness of a larger foundation mat.

illustration not visible in this excerpt

Fig. 4.6 Combined block-type foundation

(Crown Copyright: ACI Committee 351.3R-04)

Dynamic Analysis of Structure for Looms Industry- A Parametric Study

4.3.3 Pile foundations:

Any of the previously mentioned foundation types may be supported directly on soil or on piles. Piles are generally used where soft ground conditions result in low allowable contact pressures and excessive settlement for a mat-type foundation. Piles use end bearing, frictional side adhesion, or a combination of both to transfer axial loads into the underlying soil.

illustration not visible in this excerpt

Fig. 4.7 Pile foundations

(Crown Copyright: ACI Committee)

4.3.4 Wall type foundations:

This foundation consists of a pair of walls which support the machinery on their top. These foundations are relatively flexible.

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Fig. 4.8 Wall type foundations

(Crown Copyright: Tata McGraw Hill)

4.3.5 Framed-type foundation:

This foundation consists of vertical columns supporting on their top a horizontal frame-work which forms the seat of essential machinery. These foundations have lesser stiffness as compared to block foundation, which makes them more economical.

Dynamic Analysis of Structure for Looms Industry- A Parametric Study

Framed structures are considered to be flexible, hence their response to dynamic loads can be quite complex and depend both on the motion of its discreet elements (columns, beams, and footing) and the soil upon which it is supported.

illustration not visible in this excerpt

Fig. 4.9 Framed-type foundation

(Crown Copyright: Tata McGraw Hill)

4.4 Loads acting on the structure

Loading diagram furnished by an engineer gives magnitude, point of application and direction of all loads both static as well as dynamic.

4.4.1 Construction load

Self-weight of all structures and non-structural elements, considering density of Reinforced Cement Concrete as 25 kN/m³. It also includes a uniformly distributed load of 0.8kN/m² due to floor finish. Apart from this, an additional uniformly distributed load of 1.5 kN/m² is also applied on the roof for water proofing.

4.4.2 Live load

Machine load of 10 kN is distributed evenly among its four floor supports. Along with it, an additional live load of 2.0 kN/m² is also applied to the floor.

4.4.3 Time History Load

Harmonic Load is generated due to the unbalanced force being produced by the movement of the Sley and the impact force that propels the shuttle. The Harmonic Load caused by the Reciprocating Sley-movement is applied, having amplitude of 1.67 kN and frequency of 2.67 Hz for 100 cycles.

Dynamic Analysis of Structure for Looms Industry- A Parametric Study

4.5 Working of Shuttle Loom

A loom is a device used to weave cloth. The basic purpose of any loom is to hold the warp treads under tension to facilitate the interweaving of the weft threads. The precise shape of loom and its mechanics may vary, but the basis function is the same. Weaving is done by intersecting the longitudinal threads, the warp, i.e “that which is thrown across”, with the transverse threads, the weft, i.e. “that which is woven”. The major components for the loom are warp beams, heddles, harnesses or shafts (as few as two, four is common), shuttle, reed and take-up roll. In the loom, yarn processing includes shedding, picking, battening and take-up operations. There are three principle motions primary, secondary and ancillary.

4.5.1 Primary Motion

They are shedding, picking of shuttles or other means of weft insertion and beating-up the first two providing the means of interlacing weft with warp, and the last closing the interlaced pick of weft against the cloth already woven. They are primary in the sense that they perform the fundamental operation in the making of a woven cloth.

4.5.2 Secondary Motion

The secondary motion of a power-loom is the warp let-off, which is the means of delivering the warp to the point of weaving. These are secondary in the sense that they are not required on a simple weaving frame.

4.5.3 Ancillary Motion

The rest of the mechanisms of power-looms can be classed as auxillary. Without them a power-loom could continue to produce cloth, but they are helpful in that they carry out a part of the operative’s work, stop the loom to prevent damage to yarn, cloth or mechanism when there is breakage of material or a failure of the mechanism, and perform similar operation auxillary to interlacing of weft with warp and beating-up.

4.6 Source of Vibration - The Beating-Up Motion

The source of vibration is a beat-up mechanism that will tighten the knots and weft yarn into the cloth structure. The mechanism is assumed to have a single degree of freedom and a beater that is designed for output link. A crank-rocker type mechanism is selected for beat-up process of the looms. The warp yarns, weft yarns, knots, the position of the beat-up mechanism and the trajectory of the mechanism are presented in figure 4.10.

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Fig. 4.10 Mechanism of Beating-Up Motion

(Crown Copyright: Indian Journal of Fibre & Textile research)

The link DC is crank is an input link and the link AB is the rocker, which is an output link of the mechanism. As the crank DC performs a full rotation, whereas the rocker of the mechanism makes an oscillatory motion between two dead positions. The motion of the crank DC is transmitted to the rocker AB via the coupler link CB. The beater is joined to the rocker AB with a rigid connection. The beat-up mechanism is placed properly with regard to warp yarns.

The mechanism is driven by a motor through the input link DC. As the output link AB of the mechanism oscillates between the two limit positions following the dashed line, the teeth of the beater placed on the output link insert between the warp yarns and tighten the weft yarn and knots into cloth structure. There is a slider mechanism which moves along the cloth width together with beat-up mechanism.

Dynamic Analysis of Structure for Looms Industry- A Parametric Study

4.7 Codal Requirements

4.7.1 General requirements of Machine Foundation

The following requirements should be satisfied from the design point of view.

a. The foundation should be able to carry all the superimposed loads without causing shear or crushing failure.
b. The settlement should be within the permissible limits.
c. The combine centre of gravity of machine and foundation should as far as possible be in the same vertical line as the centre of gravity of the base plane.
d. No resonance should occur; hence the natural frequency of foundation-soil system should be either too large or too small compared to the operating frequency of the machine.
e. The amplitude under service condition should be within permissible limits. The permissible limits are generally prescribed by the machine manufacturers.
f. All the rotating and reciprocating parts of the machine should be so well balanced as to minimize the unbalanced forces or moments.
g. Where possible, the foundation should be planned in such a manner as to permit a subsequence alteration of natural frequency by changing base area or the mass of foundation.

4.7.1.1 General

a. Description of driving and driven machinery.
b. Operating speed or speed ranges.
c. Number and arrangement of cloth roll.
d. Distance between axis of main shaft and the top face of foundation.
e. Maximum rated output.

4.7.1.2 For Static Design

A detailed loading diagram, comprising plan, elevation and section showing details of communications and point of all loads on a structure; and a detailed drawing showing the position of the feet of machines should be provided.

4.7.1.3 For Dynamic Design

Details of out of balance forces and couples shall be given, together with associated frequencies for all possible modes of vibration for driving and driven machinery. These include the following:

a) External forces.
b) Harmonic torques.

4.7.2 Design Criteria

The foundation structure of machine shall be isolated at all levels from the main building and from other foundations as far as possible. Overhanging cantilevers where unavoidable shall be designed to ensure rigidity against vibration. All machine foundations shall satisfy two fundamental criteria; that resonance does not occur between the frequencies of the pulsating loads and natural frequency of structural system and also the amplitude of vibration should not exceed safe limits. Design criteria based on frequency and amplitude limits can be classed as follows:

a) Limits set by the possibility of damage or uneconomic wear to machinery.
b) Limits set by the possibility of damage to building structures.
c) Limits of structural borne vibrations to ensure comfort of person.
d) Limits set by possibility of disturbance of ground resulting in unacceptable settlement of foundation.

4.8 Various Types of Remedial Techniques

Structures which are equipped with heavy machineries are prone to some amount structural and non-structural damage. The main governing criteria for these damages are the dynamic forces generated due to the operation of reciprocating machines, rotary machines or impact machines. In this thesis, the case of looms industry has been evaluated which is a Reciprocating Machine. Looms machines imparts a dynamic load on the building due to the reciprocating motion of the “SLEY”

In today’s era with new advancement in construction practises, there are some loop- holes due to improper supervision, construction methods, material specification. Due to this there is an emergence of repairing and retrofitting the existing structure without any destruction on the existing structures. The case of a present Looms Industry building has been taken which was under resonance condition. Remedies such as, Cross Bracing below Plinth Level, Full length jacketing of Columns above Plinth Level, Partial Length jacketing of Columns above Plinth Level, Provision of Cross Tie beam and Haunches at 3.0 m height above Plinth Level.

4.8.1 Cross Bracing

In construction, cross bracing is a system utilized to reinforce building structures in which diagonal support members. Cross bracing can enhance a building’s capability to withstand lateral loads. The cross bracing is generally done by using two diagonal supports which are placed in a X shaped manner. These members take care of compression and tension forces. Depending on the forces, one brace may be in tension while the other is slack. In steel construction, steel cables may be used due to their great resistance to tension (although not resistant at all to compression). The common use for cross bracing includes bridge (side) supports, along with structural foundations. This method of construction maximizes the magnitude of loads that a structure can support.

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Fig. 4.11 Typical View of Cross- Bracing

(Crown Copyright: (a) www.myalaskafrointer.com , Courtesy : Justin

(b) www.johansteyn.edu , Courtesy : Johan Steyn)

Pure rigid frame systems are not sufficient for buildings higher than about 30 stories because the shear racking component of deflection produced by the bending of columns and girders causes the building drift to be too large. The efficiency is improved by adding truss members such as diagonals between the floor systems. Bracing types available, for incorporation into the structural system range from a concentric simple K or X brace between two columns to Knee bracing and eccentric bracing with complicated geometry. In an eccentric bracing system the connection of the diagonal brace is deliberately offset from the connection between the beam and the vertical column.

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Fig 4.12 Various Types of Bracing System

(Image Courtesy: Zahid A. Siddiqi)

The elastic stability of cross-bracing members is of a practical importance in the structural design of struts and ties, which are widely used in the construction of steel structures.

4.8.2 Jacketing of Columns

Reinforced concrete jacketing increases the member size significantly. This has the advantage of increasing the member stiffness and is useful where deformations need to be curtailed. If columns in a building are found to be slender, RC jacketing provides a better solution for avoiding buckling problems. Design for strengthening is based on composite action between the old and the new work wherein, strain compatibility calculations may have to be carried out carefully giving due accounts to

Dynamic Analysis of Structure for Looms Industry- A Parametric Study factors such as creep. As the new jacket is to behave compositely with the parent member, the new jacket can take additional loads only with the increase in the stresses & strains in the old one. Jacketing is the most popular used method for strengthening of columns with common materials like steel jacket, reinforced concrete jacket, high tensile materials like carbon fiber, glass fiber which improves the strength of column in shear and flexure. The other major advantage of column jacketing is that it improves the lateral load capacity of the building in a reasonably uniform and distributed way and hence avoiding the concentration of stiffness as in the case of shear walls.

illustration not visible in this excerpt

Fig. 4.13 Typical View of Jacketing of Column

(Crown Copyright: (a)&(b) Diamond Saw Contracting Co. LLC

( c)&(d) Sinhop Engineering Consultants Private Limited)

Dynamic Analysis of Structure for Looms Industry- A Parametric Study

[...]

• College: Gujarat University (Gujarat Technological University)
• Course: Final Year Project
• Grade: AA
• Authors: Jigar Sevalia (Author), Yogesh Rathod (Author), Sunil Kukadiya (Author), Sarthi Bhavsar (Author)
• Publication Year: 2013
• Pages: 194
• Catalog Number: V280411
• ISBN (eBook): 9783656755036
• ISBN (Book): 9783656755029
• Language: English
• Tags: Structural dynamics, Vibrations, Amplitude, Frequency, Resonance, Looms Industry, Shuttle Looms Machine, Column Jacket, Cross Bracing, Tie-Beams, Haunches, STAAD Pro. V8i