DESIGN OF STEEL STRUCTURES-1 (Based on IS : 800-2007) (and so also on Newly Revised Code IS: 883-1994)

[S.I. UNITS]

[For under-graduate and post-graduate students]

DR. RAMCHANDRA BE, M.E. (Hons.), Ph.D. (Roorkee at present I.I.T., Roorkee) Retired Professor Department of Structural Engineering M.B.M. Engineering College J.N.V. University, JODHPUR (Rajasthan) VIRENDRA GEHLOT B.E. (Civil) Consultant Engineer JODHPUR (Rajasthan) [E-mail: viren224@yahoo.co.in]

Published by:

Scientific Publishers (India) 5 A, New Pali Road, P.O. Box 91 Jodhpur 342 001 (India) E-mail: info@scientificpub.com Website: www.scientificpub.com

Reprint: 2012

1st Edition, 1970 2nd Edition, 1975 3rd Edition, 1978 4th Edition, 1981 5th Edition, 1982 6th Edition, 1984 7th Edition, 1986 8th Edition, 1989 9th Edition, 1989 10th Edition, 1992 11th Edition, 2005 12th Edition, 2009 13th Edition, 2011

ISBN: 978-81-7233-654-7

eISBN: 978-93-8610-207-2

© Dr. Ramchandra & Virendra Gehlot, 2011 All rights reserved by the author. This book or parts there of, may not be reproduced in any form without the written permission of the authors.

Lasertype set: Rajesh Ojha Printed in India

Dedicated to OUR TEACHERS

ROLE OF STEEL STRUCTRUES IN SERVICE FOR THE SOCIETY (Chat-magni aur Patt-byah)

Role of Steel Structures is useful, significant and important in service for the society due to following advantages of steel in construction Steel is strong and these structures have extremely high load-bearing capacity. 1. These may be fabricated in the workshops quickly. 2. The construction of the structures is also quick. 3. These structures may be furbished (made new again) strengthened and

remodelled, if necessary. These may be expanded or relocated. 4. These structures have long life-span. 5. These structures need few columns to stand-on, minimizing waste of

space. 6. Steel is recyclable. 7. Steel is more environment friendly. 8. If necessary, steel structures are easy to dismentle. 9. These structures can withstand earthquakes to much significant degree.

Authors fully support the views of R.K.P. Singh, Director General, Institution of Steel Development and Growth, (INSDAG).

Reference: Times of India, Dt. 14.05.2007, page 12, dated 22.5.2007 page 1.

ACKNOWLEDGEMENT

Tables and clauses from the Indian Standard Specifications have been produced in the book with the kind permission of the Indian Standards Institution.

It is desirable that for complete detail, reference be made to the latest versions of the Standards Institution, Manak Bhavan, 9, Bahadur Shah Zafar Marg, New Delhi-1, or from its branch offices at Mumbai, Kolkata, Kanpur and Chennai.

SYSTEM INTERNATIONAL d’ UNITS (SI - System of Units)

In order to avoid the conversion of results obtained by engineers working with the foot pound second system (gravitational) of units in terms of centimetre-gram second absolute system of units used by the scientists, a need of common system of units was realised. The General Conference on Weights and Measures held at Paris in 1960 finalised the System International d’ Units (SI). It is an absolute system of units. The mass is considered as fundamental unit and not the force. BIS has included a comment of transition in IS 3616-1966. ‘Recommendation on the Interna-tional System (SI) Units’ that this system has begun to replace older system of units in several branches of science and technology. The SI is a universal system of units and it has been adopted in France as a legal system and it is likely to become common in many countries. SI units have the following six basic units.

Unit of length (metre, m)

The length equal to 1,650, 763.73 wave lengths, in vacuum, of the radiation corresponding to the transition between 2p19 and 5d5 levels of the krypton η atom of mass 86 is known as one metre.

Unit of mass (kilogram, kg)

The mass of platinum-iridium cylinder deposited at the international Bureau of Weights and Measures and declared as the international prototype of the kilogram by the First General Conference of Weights and Measures is called as one kilogram.

Unit of time (second, s)

1131, 566, 925, 974.7 of the length of the tropical year for 1900, the year commencing at 12:00 hours universal time on the first day of January, 1900 is termed as one second.

Unit of electric current (ampere, A)

The constant current which flows in two parallel straight conductors of infinite length of negligible circular cross-section and placed at a distance of one metre from each other in vacuum producing a force of 2 × 10–7 Newtons per metre length between the conductors is defined as one ampere.

Unit of thermo-dynamic temperature (degree Kelvin, ˚K)

The degree interval of the thermodynamic scale on which the tempe-rature of triple point of water is 273.16º, is known as one degree Kelvin.

Units of luminous intensity (candela, cd)

One sixtieth part of luminous intensity normally emited by one hundred millimetre square of integral radiator (black body) at the temperature of solidification of platinum is called as one candela.

Following are the derived units (derived from the basic SI units and these are relevant for the study of design of steel structures).

Force Newton (N) kg.m. s–2 Work-energy Joule (J) kg.m2 , S–2 = (N – m) Power Watt (W) kg.m2 . s–3 = (J . s–1) Frequency Hertz (Hz) Cycles/sec. Accereation due to gravity used is 9.81 ms-2. The force is a derived quantity and physical law connecting the

quantity to the fundamental quantities or previously obtained derived quantities is force = mass x acceleration. It is defined as that force which produces unit acceleration (i.e., 1 m per sec2 in a unit mass of 1 kg). Its unit is Newton (N). Though, the Newton is a small unit, a still larger unit kN may be used. The intensity of force (viz. stress) due to 1 Newton over a unit area of one metre quare is known as one pascal. It is denoted by symbol, Pa (1 Pa = 1 N/m2 and 106. Pa = 1 N/mm2. (viz. 1 MPa = 1 N/mm2).

The unit of force, the Newton (N) is the force required to develop unit acceleration (m s−2) to unit mass (kg). In terms of Newtons, the common force units in the foot-pound second system (with g=9.81 ms-2) are

1 lb-wt = 4.45 Newtons (N) 1 ton-wt = 9.96 x 10-3 Newtons (N) 1 ton-wt = 9.96 kN

The unit of force, the Newton (N) is used for the external loads and the internal forces, such as the shear force. Torque and bending moments are expressed as Newton-metres (N-m).

Another important unit is stress. In the foot-pound-second system the stresses are commonly expressed in lb-wt/in2 and tons/in2. In the SI system of units, these are taken as

1 lb. wt ⁄in2 = 6.89 × 103 N ⁄mm2 6.89 kN ⁄m2 1 ton. wt ⁄in2 = 15.42 × 106 N ⁄mm2 = 15.42 MN ⁄m2

Yield stress of the common metallic materials are in the range 200 MN/m2 to 750 MN/m2. Yound modulus of elasticity, E for steel

Esteel = 30 × 106 lbs.wt ⁄in2 = 2.07 × 105N ⁄mm2 = 207 GN ⁄m2 The SI units make the use of multiples and sub-multiples 1000 times or

1/1000 times the unit quantity and in powers of 103 (kilo) or 10-3 (milli) in respect of still larger and smaller quantities respectively. The lengths are measured usually in kilometre (1 km = 1000 m), metre and millimetre (1 mm = 10-3 m). The symbols of units are not to be suffixed with ‘s’ for plural.

[(kilo k 10+3), (mega M 10+6), (giga G 10+9)] SI system of units have many advantages. The units are very handy. The

burden of nn-decimal coefficients in foot-pound second system is avoided. It has relatively large main units in contrast to centimetre-gram-second system. At the same time, it is closely related to centimetre-gram-second sytem of units. In practice, it results in perfectly reasonable number when the value of g = 10 m/sec2 is used instead of 9.806 m/sec2.

References

1. (Professor V.S. Mokashi, Visvesvaraya Regional College of Engineering, Nagpur in his paper titled as Interantional System (SI) Units and their Application to Engineering published in Journal of Institution of Engi-neers, India Vol. 19, March 1970 has high lighted the advantages and discussed SI units. A reference has been made to this paper).

2. John Case and A.H. Chilver ‘Strength of Materials and Structures’ Second Edition (ELBS)/ Edward Arnold, 1986, Printed of the Bath Press, Avon, Great Britain.

PREFACE (Thirteenth Edition)

In this thirteenth edition of this book, authors have made efforts to familiarise the students, types of structures (i.e., skeletal structures, stressed-skin structures and space structures). Durability of steel-structures (an essential and important aspect) has been emphasized. Details about the corrosion, its types and methods of protection of steel have also been described. In addition to this, complete text has been updated and have been added. Some photo-plates have been included to acquaint the students speci-ally about universal testing machine, compression testing machines and failures of mild steel and cast-iron specimens. Authors like to extent their sincere affection for the students for their interest and advise them to SEE PREFACE and VERIFY that it is new edition published by M/s Scientific Publishers (India), Jodhpur. Inspite of careful scrutiny of the manuscript, it is possible that some typographical and computational errors are still left. Authors shall feel highly obliged to those, who brings these errors to their notice. Suggestions from the readers for the further impovement of the book shall be appreciated. Authors express their heartly thanks to Shri Rajesh Ojha (Laser typeset) and also thanks to Shri Pawan Kumar Sharma M/s Scientific Publishers (India), Jodhpur for nice get-up and publication. 12 February, 2011 Ramchandra

Virendra Gehlot

PREFACE (First Edition)

In this book, the author with his long teaching experience in the subject has made an attempt to present the subject matter of design of steel structures in a way which lays emphasis on the fundamentals, keeping in view the difficulties experienced by the students. Every basic principle, method, equation or theory has been presented in simplified manner. Metric system of units has been used throughout the text. Indian Standards Specifications have been followed. The book is intended for the use of degree, diploma and A.M.I.E. students in various branches of engineering. The book deals with design of structural members and their connections. Each topic introduced is thoroughly described. A number of design problems including problems for examinations of the University of Jodhpur, and A.M.I.E. has been solved to illustrate the theory and practice. Slide-rule computation accuracy is adequate for the design and has been followed. The chapters have been so arranged that it facilitates self-understanding of the subject, during study. In spite of careful scrutiny of the manuscript, it is possible that some typo-graphical and computational errors are still left. The author shall be highly obliged to any one who brings these errors to his notice. The author is thankful to Shri J.N. Srivastava and other colleagues who have very generously helped with their suggestions. The author is also thank to the University of Jodhpur, Jodhpur and the Institution of Engineers, India, for following the use of their examinations, problems. Suggestions from the readers for the improvement of the book are welcome. September, 11, 1970 RAMCHANDRA

CONTENTS

PART - I (STEEL STRUCTURES) CHAPTER-1: INTRODUCTION ....................01-29 1.1 Introduction ........................................................ 01 1.2 Steel ..................................................................... 02 1.3 Structural steel ................................................... 04 1.4 Mild Steel ............................................................ 05 1.5 High Tensile Steel .............................................. 07 1.6 Weldable steel ................................................... 10 1.7 Stainless steel ..................................................... 10 1.8 Production of Steel ............................................. 10 1.9 Recent Development in Material ...................... 11 1.10 Advantages and Disadvantages of Steel

members ............................................................ 12 1.11 Rolled Structural Steel Sections ..................... 12 1.12 Rolled Steel Beam Sections ............................. 13 1.13 Rolled Steel Channel Sections ......................... 15 1.14 Rolled Steel Tee Sections ................................. 16 1.15 Rolled Steel Angle Sections ............................. 17 1.16 Rolled Steel Bars .............................................. 18 1.17 Rolled Steel Tubes ........................................... 18 1.18 Rolled Steel Flats ............................................. 19 1.19 Rolled Steel Sheets and Strips ........................ 19 1.20 Rolled Steel Plates ........................................... 20 1.21 Recent Developments in Sections ................... 20 1.22 Structures ......................................................... 20 1.23 Classification of Structures ............................. 21 1.24 Classification of Structural members ............. 23 1.25 Specifications and Building Codes .................. 23

CHAPTER-2: LOADS, METHODS OF DESIGN & PROPERTIES OF STEEL ...................30-89

2.1 Introduction ........................................................ 29 2.2 Dead Loads ......................................................... 30 2.3 Live Loads ........................................................... 34 2.4 Wind Loads ......................................................... 43 2.5 Snow Loads ......................................................... 46 2.6 Seismic Loads (Earthquake Forces) .................. 46 2.7 Soil and Hydrostatic Pressure ........................... 49 2.8 Erection Effects .................................................. 49 2.9 Dynamic Load and its Effects (Impact) ............ 49 2.10 Temperature Effects ........................................ 49

2.11 Load Combinations ...........................................50 2.12 Stresses ..............................................................50 2.13 Stress-Strain Relationship for mild-steel ...... 50 2.14 Tensile Stress................................................... 52 2.15 Compressive Stress.......................................... 53 2.16 Bearing Stress.................................................. 53 2.17 Working Stress (Allowable stresses) .............. 53 2.18 Increase in Permissible Stresses .................... 54 2.19 Methods of Design ........................................... 54 2.20 History of Elastic Method of Design............... 54 2.21 Elastic Method of Design ................................ 55 2.22 Semi-Rigid Design ........................................... 56 2.23 Fully-Rigid Design........................................... 57 2.24 History of Plastic Method of Design ............... 57 2.25 Plastic Method of Analysis and Design.......... 59 2.26 Structural Safety and Factory of Safety ........ 61 2.27 Mechanical Properties of Steel ....................... 63 2.28 Durability and Corrosion of Steel................... 66 2.29 Fire Resistance................................................. 73 2.30 Hardness of Steel ............................................. 75 2.31 Brittleness of Steel .......................................... 80 2.32 Resilience of Steel .............................................80 2.33 Toughness of Steel ............................................80 2.34 Relation between Young’s Modulus of

Elasticity, E and Modulus of Rigidity, G ........83 2.35 Relation between Young’s Modulus of

Elasticity, E and Bulk Modulus, K .................85 2.36 Bauschinger’s Effect .........................................86 2.37 Stability of Structures ......................................87 2.38 Stiffness of Structures ......................................88

CHAPTER-3: RIVETED CONNECTIONS.......................................90-136

3.1 Introduction.........................................................90 3.2 Rivets ...................................................................90 3.3 Rivet Heads ........................................................92 3.4 Rivet Holes ..........................................................92 3.5 Definition of Terms used in Riveting ................93 3.6 Working Stress in Rivets....................................93 3.7 Riveted Joints .....................................................94 3.8 Transmission of Load in Riveted Joints........... 96

3.9 Failure of A Riveted Joint ................................ 97 3.10 Strength of Riveted Joint ............................... 99 3.11 Efficiency or Percentage Strength of

Riveted Joint .................................................. 103 3.12 Rivet value .................................................... 103 3.13 Design of Riveted Joint................................. 103 3.14 Arrangement of Rivets.................................. 104 3.15 Specifications for Design of Riveted

Joint ................................................................ 105 3.16 Design Procedure for Riveted Joint ............. 107 3.17 Eccentric Riveted Connections..................... 115 3.18 Design of Eccentric Riveted Connections Subj-

ected to Direct Shear & Twisting moment .. 115 3.19 Design of Eccentric Riveted Connections subje-

cted to Direct Shear and External moments 119 3.20 Reasons of Riveted connections Becoming

out-of-use......................................................... 133

CHAPTER -4 : BOLTED CONNECTIONS .................................... 137-158

4.1 Introduction..................................................... 137 4.2 Advantage of Bolted Connections .................. 137 4.3 Disadvantage of Bolted-connections .............. 137 4.4 Bolts ................................................................. 138 4.5 History of High strength friction

Grip Bolts ....................................................... 143 4.6 High Strength Bolts ........................................ 145 4.7 Definitions of Terms used in Bolts and

Bolting ............................................................ 146 4.8 Bolt, Nut and Washer Assembly .................... 147 4.9 Stress in Bolts ................................................. 148 4.10 Permissible Stresses in Bolts ....................... 150 4.11 Concentrations of Stress in Bolts................ 150 4.12 Proof-Load and Bolt-Tension in High

strength Bolts ................................................ 151 4.13 Transfer of Load in HSFG-Connections ...... 152 4.14 Difference between Nominal Stresses

and Actual Stresses ....................................... 153 4.15 Friction Type Connections............................ 153 4.16 Bearing-Type Connections ........................... 154 4.17 Design of High Strength Friction

Grip Bolts ........................................................ 154

CHAPTER -5 : PIN-CONNECTIONS........ 159-165

5.1 Introduction..................................................... 159 5.2 Advantages of Pin-Connections...................... 159

5.3 Disadvantages of Pin-Connections ................. 159 5.4 Pins ................................................................... 160 5.5 Pin Connection ................................................ 161 5.6 Stresses in Pins................................................ 162 5.7 Permissible Stresses in Pins ........................... 163 5.8 Transfer of Load in Pin-Connections.............. 163

CHAPTER-6: AXIALLY LOADED COLUMNS & COMPRESSION MEMBERS ..........166-265

6.1 Introduction...................................................... 166 6.2 Basic Concepts of Stability.............................. 167 6.3 Structural Instability ...................................... 168 6.4 Assumptions of Determining Basic

Column Strength............................................. 169 6.5 Euler’s Buckling Load for an Axially

Loaded Columns.............................................. 170 6.6 Stub Columns

(Compression Test Specimen) ........................ 174 6.7 Slender (Long) Columns and Compression

members........................................................... 176 6.8 Residual stresses in Hot-Rolled Steel

Sections ............................................................ 176 6.9 Effective Length of Compression

members........................................................... 178 6.10 Effective Sectional Area ................................. 182 6.11 Radium of Gyration of Cross-Sectional

shape ................................................................ 182 6.12 Slenderness Ratio for Compression

Members ......................................................... 182 6.13 Possible Modes of Failure for Axially

Loaded columns............................................... 183 6.14 Column Formulae for Axial Stress in

Compression (A Historical Review) ..............185 6.15 Merchant-Rankine Formula ......................... 209 6.16 Rolled Steel Sections used as

Compression Members.................................... 212 6.17 Strength of Compression Members .............. 213 6.18 Strength of Angle-Sections used as

Struts ............................................................... 214 6.19 Strength of Built-up Compression

Members ......................................................... 217 6.20 Width-Thickness Ratio of Elements in

Compression Members ...................................221 6.21 Design of Axially Loaded Compression

Members .......................................................... 229 6.22 Laced and Battened Columns....................... 236 6.23 Batten-Plates ................................................. 253

6.24 Perforated cover-plates ................................. 260

CHAPTER -7 : ECCENTRICALLY LOADED COLUMNS.............................................. 266-300

7.1 Introduction..................................................... 266 7.2 Design of Eccentrically Loaded Columns ..... 270 7.3 Modified and Adjusted Inter-action

formulae .......................................................... 276 7.4 Equivalent Axis-Load Method of Design of

EccentricallyLoaded Columns ...................... 280 7.5 Bending-Factor Method of Design of

Eccentrically Loaded Column ....................... 282 7.6 Column-Splice ................................................. 287 7.7 Design of Column-Splice................................. 288 7.8 Encased - Columns.......................................... 294

CHAPTER -8 : SLAB AND GUSSETED BASES FOR COLUMNS ................................... 301-315

8.1 Introduction..................................................... 301 8.2 Design of Slab-Base for A Column................. 302 8.3 Design of Gusseted Base for A column .......... 305 8.4 Column Bases subjected to Moments ........... 309

CHAPTER -9 :INDEPENDENT AND COMB- INED COLUMN FOOTINGS ............. 316-329

9.1 Introduction..................................................... 316 9.2 Independent Column Footing......................... 316 9.3 Design of Combined Column Footing ............ 323 9.4 Approximate method of Design of

Combined Footing........................................... 327

CHAPTER -10 : TENSION MEMBERS.............................................. 340-366

10.1 Introduction .................................................. 340 10.2 Type of Tension members ............................ 340 10.3 Net-Sectional Area ........................................ 343 10.4 Net-Effective Section for Angles and

Tees in Tension............................................... 345 10.5 Allowable Stress in Axial Tension ............... 346 10.6 Strength of A member in Axial Tension ..... 347 10.7 Design of Tension Members Subjected

to Axial Tension.............................................. 351 10.8 Design of Tension Members subjected

to both Bending and Axial Tension .............. 352 10.9 Tension member splice ................................. 357 10.10 Lug-Angles................................................... 359 10.11 Shear-Lag .................................................... 362

CHAPTER-11: BENDING (FLEXURAL) STREN- GTH OF LATERALLY SUPPORTED (RESTRAINED) STEEL BEAMS (LSSB -I) .................................................367-420

11.1 Introduction ................................................... 367 11.2 Bending (Flexural) Stress ............................. 370 11.3 Effective Spans of Beams ............................. 386 11.4 Behaviour of Beams in Elastic Range ......... 386 11.5 Laterally Supported Beams ......................... 387 11.6 Design of Laterally (Restrained)

supported Beams............................................. 390 11.7 Built-up Beams ............................................. 397 11.8 Design of Built-up Beams ............................ 399 11.9 Lintels ............................................................ 406 11.10 Jack Arch...................................................... 408 11.11 Filler Joists................................................... 411 11.12 Encased Beams ............................................ 414

CHAPTER -12 :SHEAR STRENGTH OF STEEL BEAMS (LSSB -II) ..................421-432

12.1 Introduction ................................................... 421 12.2 Web Crippling ................................................ 423 12.3 Web Buckling ................................................. 425 12.4 Design of Rivets Connecting Cover Plates with

the Flanges of Beams .....................................431

CHAPTER-13: STIFFNESS & DEFLECTIONS OF STEEL BEAMS (LSSB-III) ..........433-438

13.1 Introduction ................................................... 433 13.2 Effects of Deflections ..................................... 434 13.3 Methods of Controlling Deflections .............. 435 13.4 Limitations of Vertical and Horizontal

Deflections in Crane Structures ....................436

CHAPTER-14: BENDING (FLEXURAL) & SHEAR STRENGTH OF LATERALLY UNSUPPORTED (UNRESTRAINED) STEEL BEAMS (LUSB-IV) .................439-474

14.1 Introduction ................................................... 439 14.2 Elastic Critical Stress for Symmetrical

Sections ............................................................ 440 14.3 Lateral Torsional Buckling of Beams with

Compact Cross-sections .................................440 14.4 Beams of Different Cross-sectional shapes

and Lateral Torsional Buckling ....................442 14.5 Effective Length of Compression Flange ..... 457 14.6 Crane Gantary Girder ................................... 463

CHAPTER-15: SIMPLE BEAM CONNECTIONS ................................... 475-514

15.1 Introduction .................................................. 475 15.2 Framed Connections ..................................... 478 15.3 Unstiffened Seated Connections ................. 480 15.4 Stiffened seated Connections ...................... 481 15.5 Design of Framed Connections ................... 482 15.6 Design of Unstiffened seated Connections ... 484 15.7 Design of Stiffened Seated Connections ..... 486 15.8 Small Moment Resistant Connections ........ 496 15.9 Large Moment Resistant Connections ........ 498

CHAPTER -16 : SEMI-RIGID CONNECTIONS ................................... 515-529

16.1 Introduction .................................................. 515 16.2 Behaviour of Semi-Rigid Connections ........ 516 16.3 Beam-Line Method ....................................... 520 16.4 Modified Slope-Deflection Method .............. 522 16.5 Modified Moment Distribution Method ...... 525

CHAPTER-17: BENDING (FLEXURAL) STRENGTH OF PLATEGIRDERS (RPG-I) ................................................... 530-565

17.1 Introduction .................................................. 530 17.2 Elements of Plate Girder ............................. 532 17.3 Area of Flanges of Plate Girder ................... 532 17.4 Depth of Plate Girder ................................... 534 17.5 Economical Depth of Plate Girder .............. 536 17.6 Self-Weight of Plate Girder ......................... 537 17.7 Impact ........................................................... 538 17.8 Assumptions for Design of Plate Girder ..... 539 17.9 Allowable Bending Stress ............................ 539 17.10 Design of Web-plate ................................... 540 17.11 Design of Flanges ....................................... 540 17.12 Length of Flange plates (curtailment of

Flange Plates) ................................................ 548 17.13 Connection of Flange Angles to Web ........ 558

CHAPTER-18: SHEAR STRENGTH OF PLATE GIRDERS (RPG-II) ............... 566-592

18.1 Introduction .................................................. 566 18.2 Web Buckling in Pure Shear ....................... 570 18.3 Shear Capacity of Web Plates ..................... 575 18.4 Diagonal Buckling of Web ........................... 578 18.5 Load Bearing Stiffeners ............................... 580 18.6 Intermediate Stiffeners ............................... 582

18.7 Vertical Stiffeners .........................................583 18.8 Horizontal Stiffeners ....................................584 CHAPTER-19: WEB SPLICE AND SPLICE IN

FLANGEELEMENTS OF PLATE GIRDERS (PG-III) ...............................593-613

19.1 Introduction ...................................................593 19.2 Web-Splice (Rational Method) .....................593 19.3 Web-Splice (Moment-Splice) ........................598 19.4 Web-Splice (Shear-splice) ............................. 602 19.5 Flange Splice .................................................607 19.6 Splice of Flange Elements ............................607 19.7 Splice of Flange plates ..................................608

CHAPTER-20: WELDED JOINTS SUBJECTED TO AXIAL LOAD .........614-652

20.1 Introduction ...................................................614 20.2 Advantages of Welding .................................617 20.3 Dis-advantages of welding ...........................617 20.4 Types of Welded Joints .................................618 20.5 Butt-Weld ......................................................618 20.6 Fillet-Weld .....................................................622 20.7 Slot-weld and Plug-weld ...............................626 20.8 Imperfections in Weld ..................................628 20.9 Stresses in Welds ..........................................631 20.10 Combined Stresses in Welds ......................637 20.11 Working Stresses in Welds ........................640 20.12 Design of Welded Joints Subjected to

Axial Load .......................................................643

CHAPTER -21 : WELDED JOINTS SUBJECTED TO ECCENTRIC LOAD .......................................................653-668

21.1 Introduction ...................................................653

CHAPTER -22 : WELDED PLATE GIRDER (WPG) ....................................669-681

22.1 Introduction ...................................................669 22.2 Design of Web ...............................................670 22.3 Design of Flanges ..........................................670 22.4 Design of Connection of Flange Plate

and Web .......................................................... 671 22.5 Design of Bearing Stiffener ..........................672 22.6 Intermediate Stiffeners ................................672

CHAPTER -23 : WELDED BEAM CONNECTIONS ....................................682-697

23.1 Introduction ...................................................682

23.2 Direct Welded Connections ......................... 685 23.3 Welded Framed Connections ....................... 685 23.4 Welded Seat Connections ............................ 690 23.5 Moment Resistant Welded Connections ..... 694

CHAPTER -24 : BEAMS SUBJECTED TO UNSYMMETRICAL BENDING ......... 698-731

24.1 Introduction .................................................. 698 24.2 Principal Axes of Section ............................. 699 24.3 Location of Principal Axes by Analytical

Method ............................................................ 700 24.4 Location of Principal Axes by Graphical

Method ............................................................ 702 24.5 Maximum Bending Stress due to

Unsymmetrical Bending ............................... 705 24.6 The Z-Polygon ............................................... 711 24.7 Deflection of Beams, under

Unsymmetrical Bending ............................... 715 24.8 Design of Purlins subjected to Unsymmetrical

Bending .......................................................... 718 24.9 Design of Angle-Iron Purlins ....................... 720

CHAPTER -25 : ROOF TRUSSES ............ 732-798

25.1 Introduction .................................................. 732 25.2 Types of Trusses ........................................... 733 25.3 Various Terms Used in Roof-Trusses ......... 734 25.4 Economical Spacing of Roof-Trusses ........... 737 25.5 Roof Coverages ............................................. 738 25.6 Load on Roof-Trusses ................................... 740 25.7 Design Wind Speed ...................................... 746 25.8 Design Wind Pressure ................................. 751 25.9 Wind Forces (Loads) on Buildings/

Structures ...................................................... 752 25.10 Wind Load on Individual Members .......... 753 25.11 External Pressure Coefficients .................. 753 25.12 Internal Pressure Coefficients .................. 764 25.13 External Pressure Coefficients for

some other Roofs ............................................ 765 25.14 Combination of Loads on Roof-Trusses .... 768 25.15 Bracing of Roof-Trusses ............................. 770 25.16 Assumptions in Analysis of

Roof-Trusses ................................................... 771 25.17 Design of Roof Trusses ............................... 775 25.18 Typical Details of Roof Trusses ................. 779

CHAPTER -26 : ROUND TUBULAR STRUCTURES ......................................799-813

26.1 Introduction ...................................................799 26.2 Round Tubular Sections ...............................800 26.3 Permissible Stresses .....................................802 26.4 Tube Columns and Compression

Members ......................................................... 804 26.5 Crinkling of Tubular Sections ......................806 26.6 Tube Tension Members ................................806 26.7 Tubular Roof Trusses ...................................806 26.8 Joints in Tubular Trusses ............................807 26.9 Design of Tubular Beams .............................810 26.10 Design of Tubular Purlins ..........................810

PART II (TIMBER STRUCTURES)

CHAPTER -27 :TIMBER COLUMNS AND TENSION MEMBERS ..........................814-840

27.1 Introduction .....................................................814 27.2 Defects in Timber ...........................................814 27.3 Decay of Timber .............................................816 27.4 Preservation of Timber .................................817 27.5 Seasoning of Timber ...................................... 818 27.6 Grading of Timber ......................................... 818 27.7 Sap Wood and Heart Wood ........................... 820 27.8 Grains of Timber............................................ 821 27.9 Strength of Timber ........................................ 822 27.10 Factor of Safety............................................ 823 27.11 Working Stresses in Timber ....................... 824 27.12 Bearing stress in Timber............................. 826 27.13 Solid Wood Columns................................... 827 27.14 Built-up and Box Columns.......................... 829 27.15 Spaced Columns .......................................... 830 27.16 Columns subjected to Combined Stress ..... 832

CHAPTER-28: BENDING (FLEXURAL) AND SHEAR STRENGTH OF TIMBER BEAMS ..................................841-852

28.1 Introduction ................................................... 841

CHAPTER-29: JOINTS OF TIMBER STRUCTURAL COMPONENTS ........853-864

29.1 Introduction ................................................... 853 29.2 Lap, Scarf and Fish Plate Joints .................. 854 29.3 Bolted Joints in Timber................................. 855

CHAPTER -30 : NAILED JOINTS IN TIMBER.................................................. 865-877

30.1 Introduction .................................................. 865 30.2 Strength of Nailed Joints.............................. 870

CHAPTER -31 : DISC DOWELLED JOINTS AND METAL CONNECTORS ............ 878-887

31.1 Introduction .................................................. 878 31.2 Metal Connectors in Timber......................... 883

CHAPTER -32 : TIMBER ROOF TRUSSES................................................ 888-893

32.1 Introduction .................................................. 888 PART - III (MASONRY STRUCTURES)

CHAPTER -33 : MASONRY STRUCTURES....................................... 894-911

33.1 Introduction .................................................... 894 33.2 General Conditions of Stability of

Masonry Structures......................................... 895 33.3 Earth Pressure ............................................... 897 33.4 Lateral Earth Pressure on Retaining

Walls with Dry and Moist Back fill with no Surcharge ........................................................ 897

33.5 Lateral Earth-Pressure on Retaining Walls with Sub-merged Back-fill ................... 899

33.6 Lateral Earth-Pressure on Retaining Walls with uniform Surcharge ...................... 899

33.7 Lateral Earth-Pressure on Retaining Walls with Back-fill with sloping surface ................ 900

33.8 Lateral Earth-Pressure on Retaining Wall with Inclined Back and surcharge ................. 901

33.9 Hydro-static Pressure of Water.................... 903 33.10 Masonry Dams ............................................ 905 CHAPTER -34 : MASONRY CHIMNEYS . 912-919 34.1 Introduction .................................................. 912

34.2 Lining for Masonry Chimneys ...................... 912 34.3 Various Forces Acting on Masonry

Chimney........................................................... 913 34.4 Stability of Masonry Chimneys .................... 915 34.5 Architectural Treatment of Masonry

Chimneys ......................................................... 916 34.6 Specifications for Design of Masonry

Chimneys ......................................................... 916

APPENDIX -A ................................................920-958

A.1 Introduction..................................................... 920 A.2 General Bending Theory ................................ 925 A.3 Shear Stresses due to Bending of Thin-walled

open Cross-sections ........................................928 A.4 Shear Centre and Shear Flow in open Thin

Cross-sections of a Beam ...............................930 A.5 Determination of Shear Centre for a given

Cross-section ................................................... 931 A.6 Shear Centre for a channel Section with

Parallel Flanges .............................................. 932 A.7 Shear Centre for A Thin-Walled Z-Beam

Cross-section.................................................... 942 A.8 Shear Centre for Thin-Walled Open

I-Section with unequal flanges ......................944 A.9 Shear Centre for Thin-Walled

Tee-section ...................................................... 946 A.10 Shear Centre for A Thin-walled Equal

Leg Sections..................................................... 947 A.11 Location of Shear-Centre ............................. 948 A.12 Shear Centre for A Thin-Walled

Section (An Arc of A circle) ............................954 References ........................................................957

APPENDIX -A1 ..............................................959-972

INDEX............................................................. 973-984

CONTENTS (Design of Steel Structures - 2)

PART I STEEL BRIDGES AND INFLUENCE

LINE DIAGRAMS

1. STEEL BRIDGES .....................................1-42

1.1 Introduction .................................................. 01

1.2 Classification of Steel Bridges ......................02 1.3 Movable Bridges ............................................18 1.4 Comparison of Fixed and Movable

Bridges .........................................................22 1.5 Selection of Type of Bridges ..........................23 1.6 Exection Methods of Bridges ........................24

1.7 Economical span Length .............................. 28 1.8 Clearance ...................................................... 30 1.9 Width of Roadway and Foot way ................. 32 1.10 Dimension of Rolling stock......................... 32 1.11 Historical Development of Bridge .............. 34

2. LOADS, METHODS OF DESIGN AND STRESSES ..........................................43-104

2.1 Introduction .................................................. 43 2.2 Dead Loads ................................................... 43 2.3 Live Load ...................................................... 44 2.4 Impact Load (Dynamic Effect) ..................... 75 2.5 Wind Load ..................................................... 78 2.6 Lateral Load ................................................. 79 2.7 Longitudinal Force ....................................... 79 2.8 Centrifugal Force .......................................... 87 2.9 Seismic Force (Earthquake Forces) ............. 88 2.10 Erection Effects .......................................... 88 2.11 Temperature Effects ................................... 89 2.12 Secondary Stresses ..................................... 89 2.13 Relief Stresses ............................................. 89 2.14 Combination of Loads ................................. 89 2.15 Allowable stresses ...................................... 90 2.16 Allowable stresses for combination of

Loads............................................................. 97 2.17 Combined stress .......................................... 97 2.18 Fatigue and Fracture .................................. 98 2.19 Endurance Limit (or Fatigue Limit) ........ 102 2.20 Design of Bridges....................................... 103

3. PLATE GIRDER (SOLID WEB GIRDER) BRIDGES ..........................................105-169

3.1 Introduction ................................................. 105 3.2 Types of Floors............................................ 105 3.3 Deck Type Plate Girder Bridge................... 106 3.4 Through Type Plate Girder Bridge............. 107 3.5 Bracing of Deck Type Plate Girder

Bridges ........................................................ 108

3.6 Bracing of Through Type Plate Girder Bridges ............................................108

3.7 Self-Weight of Plate Girders........................109 3.8 Assumptions for the Design of Plate

Girder Bridges ...........................................110 3.9 Design of Plate Girders for Deck Type

Railway Bridges (Design of maximum Section) ...................110

3.10 Design of Stringers, Cross-Girders, and Main Plate Girders for Through Type Railway Bridges ................................116

3.11 Curtailment of Flange Plate..................... 124 3.12 Design of connections of Flange

Elements .....................................................125 3.13 Design of Stiffeners....................................125 3.14 Design of stringers, Cross-Girders and

Plate Girders for Highway Bridges........... 138 3.15 Wind Load on Plate Girder Bridges .........151 3.16 Wind Effects on Plate Girder Bridges ......152 3.17 Design of Horizontal Truss Bracing..........165 3.18 Design of Cross-frames ..............................165 3.19 Design of Internal Gusset Plates ..............166

4. TRUSS GIRDER (OPEN WEB/LATTICE GIRDER) BRIDGES ....................... 173-247

4.1 Introduction..................................................173 4.2 Types of Truss Girder Bridges ....................174 4.3 Deck Type and Through Type

Truss Bridges ..............................................176 4.4 Component Parts of A Truss Bridge ...........177 4.5 Economic Proportions of Trusses ...............178 4.6 Self Weight of Truss Girders ......................179 4.7 Assumptions for the Design of Truss

Bridges .......................................................181 4.8 Compression Members ................................181 4.9 Tension Members.........................................186 4.10 Bracing of Deck Type Truss Girder

Bridges ....................................................... 211 4.11 Bracing of Through Type Truss Girder

Bridges ........................................................211

4.12 Wind Loads on Truss Girder Bridges ...... 211 4.13 Wind Effect on Truss Girder Bridges ...... 212 4.14 Top Lateral Bracing .................................. 214 4.15 Bottom Lateral Bracing............................. 215 4.16 Portal Bracing............................................ 228 4.17 Assumptions for the Analysis of Portal

Frames ........................................................ 230 4.18 Analysis of Portal Bracing ........................ 230 4.19 Analysis of Portal Bracing

(as shown in Fig. 4.43) .............................. 232 4.20 Analysis of Portal Bracing

(as shown in Fig. 4.44) .............................. 235 4.21 Analysis of Portal Bracing

(as shown in Fig. 4.45) .............................. 239 4.22 Analysis of Portal Bracing

(as shown in Fig. 4.46) .............................. 240 4.23 Sway Bracing ............................................. 246

5. END BEARINGS FOR STEEL BRIDGES ..........................................248-279

5.1 Introduction ................................................. 248 5.2 Functions of End Bearings.......................... 248 5.3 Types of End Bearings ................................ 250 5.4 Selection of Type of End Bearings .............. 251 5.5 Ferrous Mechanical Bearings ..................... 253 5.6 Allowable Stresses in Ferrous Bearings..... 259 5.7 Non Ferrous Mechanical Bearings ............. 268 5.8 Elastomeric Bearings .................................. 268 5.9 Static Behaviour of Elastomers .................. 269 5.10 Types of Elastomeric Bearings.................. 274 5.11 Design of Elastomeric Bearings................ 275 5.12 Elastomeric Pot Bearings.......................... 278

6. INFLUENCE LINE DIAGRAMS FOR STRESSES IN FRAMES .................280-281

6.1 Introduction ................................................. 280 6.2 Object of Drawing Influence Line

Diagrams .................................................... 280

7. INFLUENCE LINE DIAGRAMS FOR STRESSES IN MEMBERS OF A PRATT TRUSS WITH PARALLEL CHORDS ........................................... 282-290

7.1 Introduction.................................................282 7.2 Influence Line Diagrams for Stresses in

Members of A Warren Truss with Parallel Chords ........................................................286

7.3 Influence Line Diagrams for Stresses in Members of A K-Truss ...............................290

8. INFLUENCE LINE DIAGRAMS FOR STRESSES IN MEMBERS WITH CURVED CHORD ........................... 295-310

8.1 Introduction.................................................295 8.2 Influence Line Diagrams for Stresses in

Members of A Warren Truss with Curved chord ..............................................299

8.3 Influence Line Diagrams for Stresses of Members of A K- trusses ...........................303

9. INFLUENCE LINE DIAGRAMS FOR STRESSES IN MEMBERS OF A BALTIMORE AND A PETTIT TRUSSES WITH SUB-DIVIDED PANELS ............................................ 311-336

9.1 Introduction..................................................311 9.2 Influence Line Diagrams for stresses in

Members of A Baltimore Truss With Sub struts (Through Type) ................................319

9.3 Influence Line Diagrams for stresses in Members of A Pettit (Pennsylvania) Truss with sub-ties ...............................................324

9.4 Influence Line Diagrams for Stresses in Members of A Pettit (Pennsylvania) Truss with sub struts ...........................................330

10. INFLUENCE LINE DIAGRAMS FOR STRESSES IN MEMBERS OF A BALA-NCED CANTILEVER AND SUSPENDED SPAN GIRDER ................................ 337-340

10.1 Introduction ...............................................337

PART II. SPECIAL STEEL STRUCTURES

11. SELF-SUPPORTING STEEL CHIMNEYS .......................................342-381

11.1 Introduction .............................................. 342 11.2 Types of steel chimneys............................. 343 11.3 Steel Plates for Chimneys ......................... 343 11.4 Riveted Joints in Chimneys ...................... 345 11.5 Lining for Chimneys.................................. 345 11.6 Breech (Flue) Opening............................... 348 11.7 Ladder ........................................................ 350 11.8 Maintenance and Painting of Steel

Chimneys .................................................... 350 11.9 Lightening Conductor................................ 351 11.10 Forces acting on steel chimneys.............. 352 11.11 Bending moment at any cross section of

self supporting steel chimneys .................. 353 11.12 Bending stress at any cross-section of

steel chimney .............................................. 354 11.13 Permissible stresses ................................ 355 11.14 Design of Thickness of Steel Plates for

self-supporting Chimney ........................... 358 11.15 Design of Base Plate ............................... 359 11.16 Design of Achor Bolts ............................. 361 11.17 Design of Foundation .............................. 362 11.18 Stability of steel Chimney....................... 365 11.19 Design of Self-supporting Steel

Chimneys in General ................................. 366

12. GUYED STEEL CHIMNEYS............382-392

12.1 Introduction .............................................. 382 12.2 Classification of Guyed Steel

Chimneys .................................................... 384 12.3 Moments and Reactions due to wind for

chimneys with are st of Guy-Rope ............ 384 12.4 Moments and Reactions due to wind acting

over chimneys with two set of Guys ......... 390

12.5 Approximate method to calculate Reactions, shears and moments due to wind for chimneys with two sets of Guys ................391

12.6 Reactions and Moments due to wind for steel chimneys with three set of Guys ...............391

12.7 Pull in Guy Ropes (Cables/Wires) .............392

13. RECTANGULAR STEEL TANKS (RST) .................................................. 388-412

13.1 Introduction ...............................................388 13.2 Permissible Stresses in Water Tanks ......412

14. ELEVATED CIRCULAR STEEL TANKS (CST) .................................... 413-446

14.1 Introduction ...............................................413 14.2 Riveted Joints in Elevated Circular steel

Tanks...........................................................415 14.3 Accessories of Elevated Circular Steel

Tanks ..........................................................416 14.4 Forces acting over the Tanks.....................417 14.5 Stresses in Elevated Circular Tanks ........418 14.6 Stresses in segmental and spherical

Bottoms .......................................................418 14.7 Stresses in Conical Bottom........................420 14.8 Stresses in Connections between side and

Bottom Plates .............................................423 14.9 Circular Girder...........................................424 14.10 Staging for circular steel Tanks ..............427 14.11 Stresses in Columns ................................428 14.12 Wind Bracing ...........................................432 14.13 Stand Pipes .............................................442 14.14 Stresses in Stand Pipes ..........................445 14.15 Design of Achor Bolts ..............................446

15. PRESSED STEEL TANKS (PST) ... 448-463

15.1 Introduction ...............................................448 15.2 Capacity of Pressed Steel Tank ................451 15.3 Stays in Pressed Steel Tanks ...................451 15.4 Accessories of Pressed Steel Tanks ..........453 15.5 Staging for Pressed Steel Tanks ..............455

15.6 Permissible stresses ................................. 455

16. STEEL BUNKERS AND SILOS ....464-490

16.1 Introduction .............................................. 464 16.2 Janssen’s Theory ...................................... 466 16.3 Airy’s Theorem .......................................... 469 16.4 Design Parameters ................................... 472 16.5 Design Criteria ......................................... 473 16.6 Analysis of Bins ........................................ 475 16.7 Hopper Bottom .......................................... 478 16.8 Design of Bins ........................................... 479

17. INDUSTRIAL BUILDINGS............. 491-544

17.1 Introduction .............................................. 491 17.2 Structural Frame Work of Industrial

Buildings .................................................... 495 17.3 Floor Construction .................................... 496 17.4 Roof Construction ..................................... 497 17.5 External Wall Construction ..................... 497 17.6 Partition Walls .......................................... 498 17.7 Staircases .................................................. 498 17.8 Lighting ..................................................... 499 17.9 Heating and Ventilating ........................... 499 17.10 Crane Gantary Girders .......................... 499 17.11 Crane Columns ....................................... 501 17.12 Bracing of Industrial Building ............... 501 17.13 Bracing of Industrial Buildings in

Transverse Direction ................................. 502 17.14 Rigid Frame Buildings ........................... 504 17.15 Bracing of Industrial Buildings in

Longitudinal Direction .............................. 504 17.16 Analysis of Industrial Building Bents ... 508 17.17 Design of Industrial Building ................ 513

18. HIGH AND LOW RISE TALL (MULTI-STOREY) BUILDINGS ...545-608

18.1 Introduction .............................................. 545 18.2 Historical Review of High-Rise

Buildings..................................................... 550

18.3 Various Types of High Rise Building Structures ...................................................551

18.4 Structural System of High Rise Buildings .....................................................555

18.5 Skeleton Frame Systems .......................... 556 18.6 Load Bearing Wall Panel Systems............558 18.7 Panel Frame Systems ................................559 18.8 Multi-Storey Box-systems .........................561 18.9 Forces and Load Action on High-Rise

Buildings .....................................................562 18.10 Method of Analysis...................................566 18.11 Number of Assumptions Required ..........566 18.12 Bracing of Multi-Storey Buildings ..........566 18.13 Analysis of Multi-Storey Buildings with

moment Resistant Joints for Lateral Loads ..........................................................569

18.14 Portal Method ..........................................571 18.15 Cantilever Method ...................................573 18.16 Factor Method ..........................................575 18.17 Limitations of Portal and Cantilever

Methods ......................................................579 18.18 Analysis of Multi-Storey Buildings with

moment Resistant Joints for Gravity Loads (Vertical Loads) ...............................579

18.19 High-Rise Tubular Frames......................598 18.20 Behaviour of Tubular Frames .................603 18.21 Initial Preliminary Design Approach......605 18.22 Comparison of High Rise Structural

Systems ......................................................605

19. THIN WALLED/COLD FORMED (LIGHT GAUGE) STEEL MEMBERS) ....... 609-644

19.1 Introduction ...............................................609 19.2 Advantages of cold-Formed Steel

sections........................................................610 19.3 Types of Cross-section................................611 19.4 Definitions .................................................613 19.5 Local Buckling of Thin-Elements ..............616 19.6 Post Buckling of Thin-Elements................618

19.7 Light Gauge Steel Columns and Compression Members .............................. 619

19.8 Form-Factor for columns and compression Members ............................... 625

19.9 Behaviour of stiffened Elements under Uniform Compression ............................... 626

19.10 Stiffened Elements under Stress Gradient ..................................................... 630

19.11 Multiple Stiffened Compression Elements ..................................................... 631

19.12 Maximum Allowable over all Flat Width ratio.................................................. 633

19.13 Unstiffened compression Elements ........ 633 19.14 Effective length of Light Gauge Steel

Compression Members .............................. 633 19.15 Basic Design Stress ................................. 634 19.16 Allowable Design stress in

Compression ............................................... 634 19.17 Light Gauge Steel Tension Members ..... 638

20. THIN-WALLED/COLD FORMED (LIGHT GAUGE) STEEL FLEXURAL MEMBERS ........................................645-668

20.1 Introduction .............................................. 645 20.2 Bending strength of Beams....................... 645 20.3 Laterally Supported Light Gauge steel

Beams ......................................................... 648 20.4 Laterally un-supported Light Gauge Steel

Beams ........................................................ 649 20.5 Laterally Buckling of Cold Formed

Beams ......................................................... 650 20.6 Shear Strength of Cold Formed Beams.... 652 20.7 Cold formed Beams Subjected to combined

Bending and shear .................................... 653 20.8 Crippling of Web of Cold formed Beams... 653 20.9 Deflection of Beams .................................. 655 20.10 Allowable Design Stresses in Beams...... 655 20.11 Beams Subjected to Combined Axial

and Bending Stresses ................................ 657 20.12 Connections.............................................. 661

21.PLASTIC (ULTIMATE LOAD METHOD) ANALYSIS OF STEEL STRUCTURES ............................................................ 669- 686

21.1 Introduction ...............................................669 21.2 Ductility of Steel .......................................670 21.3 Applicability of Simple Plastic Theory of

Bending for Different Materials ................672 21.4 Perfectly plastic Material ..........................673 21.5 Ultimate Load Carrying Capacity of

Members carrying Axial Tension .............. 674 21.6 Plastic Behaviour of A Simple Truss

Structure .....................................................676 21.7 Shape factor................................................679

22. PLASTIC (ULTIMATE LOAD METHOD) ANALYSIS OF BEAMS .................. 687-739

22.1 Introduction ...............................................687 22.2 Fully Plastic Moment of A section.............688 22.3 Elastic Plastic Bending of A Rectangular

Beam............................................................690 22.4 Plastic Hinge ..............................................691 22.5 Moment Curvature Relationship ..............694 22.6 Load Factor ................................................697 22.7 Margin of Safety.........................................698 22.8 Fundamental Conditions for Plastic

Analysis.......................................................699 22.9 Mechanism .................................................699 22.10 Plastic Collapse Theorems.......................701 22.11 Static Theorem or Lower Bound

Theorem ......................................................701 22.12 Kinematic Theorem or Upper Bound

Theorem ......................................................703 22.13 Uniqueness Theorem or combined

Theorem .....................................................704 22.14 Plastic Collapse of A Structure ...............705 22.15 Collapse Load for Standard Cases of

Loadings over Beams .................................706 22.16 Collapse Load for Continuous Beams ....720 22.17 Combined Mechanism .............................723

23. PLASTIC (ULTIMATE LOAD METHOD) ANALYSIS OF RECTANGULAR PORTAL FRAMES ...........................740-768

23.1 Introduction .............................................. 740 23.2 Instantaneous Centre of Rotation (ICR) for

Plane Frames ............................................. 755

24.PLASTIC (ULTIMATE LOAD METHOD) ANALYSIS OF PITCHED ROOF PORTAL (GABLE) FRAMES .........769-782

24.1 Introduction .............................................. 769 24.2 Gable Mechanism ...................................... 771 24.3 Method of Instantaneous Centre of

Rotation (ICR) ............................................ 771

25. INFLUENCES OF AXIAL AND SHEAR FORCES ............................................783-801

25.1 Introduction .............................................. 783 25.2 Influence of Axial force as fully Plastic

Moment of A Beam Section ....................... 784 25.3 Influence of Axial Force as I-shaped

Beams ........................................................ 787 25.4 Practical Design Rules ............................. 792 25.5 Influence of Shear Force an fully Plastic

Moment of A Beam Section ....................... 794 25.6 Influence of shear Force on fully Plastic

moment of A Beam of I-section ................. 798

26. STEEL TOWERS, TRESTLES, MASTS AND POLES .......................802-844

26.1 Introduction .............................................. 802 26.2 Structure configuration

(Tower Geometry) and Material ................ 806 26.3 Feasibility of Construction........................ 807 26.4 Family of structures .................................. 807 26.5 Definition of Terms ................................... 808 26.6 Loads on Transmission Towers................. 809 26.7 Shape sag (Dip) and Tension in

Uniformly Loaded Conductors .................. 813 26.8 Design of Steel Lattice Towers ................. 816 26.9 Design of Preliminary Geometry

Tower ......................................................... 816

26.10 Analysis of Towers ..................................818 26.11 Masts .......................................................820 26.12 Trestles ....................................................821 26.13 Stresses in Trestles due to Vertical

Loads ..........................................................822 26.14 Stresses in Trestles due to Horizontal

Loads ..........................................................824 26.15 Design of Towers .....................................824 26.16 Transmission Poles .................................827 26.17 Tubular Steel Poles................................. 828 26.18 Guyed Poles .............................................829 26.19 Structural Stability of Guyed Poles .......830 26.20 Stress Analysis for Transmission

Poles ...........................................................830 26.21 Design of Tower Foundation ...................830

PART - III ALUMINIUM STRUCTURES

27. ALUMINIUM STRUCTURES ........ 845-866 27.1 Introduction ...............................................845 27.2 Chemical Composition ..............................846 27.3 Stress-strain Relationship for

Aluminium .................................................847 27.4 Properties of Aluminium Alloys ...............848 27.5 Factor of Safety .........................................849 27.6 Advantages and Disadvantages ..............849 27.7 Permissible stresses ..................................850 27.8 Tension Members ......................................850 27.9 Columns and compression Members ........851 27.10 Permissible stresses in Compression

for columns .................................................854 27.11 Effective length of columns .....................854 27.12 Laced and Battened columns .................855 27.13 Combined compression and Bending .....855 27.14 Beams ......................................................856 27.15 Local Buckling of Elements in

compression ................................................857 27.16 Riveted connections ................................ 858

PART - IV ANALYSIS OF STRUCTURES

28. METHOD OF TENSION COEFFICIENTS FOR ANALYSIS OF DETERMINATE AND INDETERMINATE SPACE STRUCTURES .................................867-887

28.1 Introduction .............................................. 867 28.2 Tension Coefficient .................................... 867 28.3 Analysis of Plane Frames......................... 868 28.4 Analysis of Determinate space

Frames ........................................................ 873 28.5 Strain Energy in A Member Carrying

Axial Force ................................................. 880 28.6 Analysis of Indeterminate space

Frames ........................................................ 881

29. SECONDARY STRESSES .............888-900

29.1 Introduction .............................................. 888 29.2 Secondary Stresses due to Rigidity of

Joints........................................................... 889 29.3 Determination of Changes in Angles of

Any Triangle .............................................. 890 29.4 Determination of Deflection Angles.......... 892 29.5 Secondary moments .................................. 893 29.6 Equilibrium of Joints................................. 893 29.7 Secondary stresses due to Bending of

Members ..................................................... 894

PART V INTRODUCTION TO SPECIAL STEEL

STRUCTURES

30. SPECIAL STRUCTURES ..............901-915

30.1 Introduction .............................................. 901 30.2 Orthotropic Steel Plate Panels and

Bridges ....................................................... 901 30.3 Analysis of Orthotropic Panels ................. 903 30.4 Analysis of Orthotropic Bridges................ 906 30.5 Tensile Structures or Tension Loaded

Structures ................................................... 906 30.6 Cables......................................................... 907

30.7 Cable Cross ................................................907 30.8 Cable Net....................................................908 30.9 Cable systems and Nets Forming

Vertical Surfaces.........................................910 30.10 Cable suspended freely to form

surfaces .......................................................910 30.11 Cable structures.......................................911 30.12 Membranes...............................................912 30.13 Difference between cable Net and

Membrane shapes .......................................913 30.14 Pre-stressed tension loaded structures ...913 30.15 Tensile stress Pneumatic structures.......914

31. SPACE STRUCTURES .................... 916-933

31.1 Introduction ...............................................916 31.2 Space Structures .......................................917 31.3 Basic Concepts ..........................................918 31.4 Advantages of space structures ................919 31.5 Definitions of various Terms ....................920 31.6 Guide lines for Preliminary Planning ......920 31.7 Double Layered Grids

(Flat surface space structures) ..................922 31.8 Selection of Type for Double Layer

Grids ...........................................................927 31.9 Supports for Double Layered Grids ......... 928 31.10 Cambering and slope ..............................930 31.11 Depth and module size ............................931 31.12 Exection methods of space structures ....932

32. STRESSED SKIN CONSTRUCTION ............................ 934-956

32.1 Introduction ...............................................934 32.2 Diaphragm Action of Steel sheet ..............935 32.3 Necessary conditions .................................935 32.4 Panel and Frame Flexibilities ..................936 32.5 Limitation on Design Method ...................937 32.6 Shear Flexibility of A Panel ......................937 32.7 Flexibility, C1, due to sheet

Deformation ...............................................938

32.8 Flexibility, C2, due to sheet Fasteners .... 941 32.9 Flexibility, C3, due to Purlin/Rafter

Connectors ................................................. 944 32.10 Flexibility of A Frame ............................ 945 32.11 Sway Flexibility of Rectangular

Portal Frame .............................................. 945 32.12 Sway Flexibility of pitched Roof

Portal Frame .............................................. 946 32.13 Spread Flexibility of Pitched Roof

Portal Frame .............................................. 946 32.14 Elastic Design Process ............................ 947

32.15 Buildings with Rectangular Portal Frames ........................................................947

32.16 Buildings with Pitched Roof Portal Frames........................................................ 948

32.17 Principles of Stressed skin Construction ...............................................940

Appendix - A (Principle of Virtual Work) ........... 957-963

Index ......................................................... 964-972

Photo-Plates : 1.1, 1.2, 1.3, 1.4, 1.5 2.1, 2.2, 2.3 18.1 26.1

LIST OF THE PAPERS PUBLISHED BY Prof. Dr. Ram Chandra* and Virendra Gehlot**

I. PAPERS PUBLISHED IN INTERNATIONAL JOURNALS

*1. ‘‘Non-Linear Analysis of Steel Space Structures,’’ Journals of American Society of Civil Engineers, Volume 116, No. 4, April, 1990, Paper no. 24525 (pp. 898-909) New York.

*2. ‘‘Elastic-Plastic Analysis of Steel Space Structures’’, Journal of American Society of Civil Engineers, Volume 116, No. 4, April, 1990 Paper no. 24528 (pp. 939-955) New York.

II. PAPERS PUBLISHED IN NATIONAL JOURNALS, CONFERENCES & SEMINARS

*3. ‘‘Non-Linear Elastic-Plastic Analysis of Skeletal Steel Plane Frames Hinged at supports’’, proceedings of the seminar on Modern trend in structural analysis and design, 25-26 February, 1984, Department of Civil Engineering, Banara Hindu University, Varanasi (U.P.)

*4. ‘‘Non-Linear Elastic Plastic Analysis of Skeletal Plane Steel Frame’’, International confe-rence on computer applications in Civil Engineering, October 23-25, 1979, University of Roorkee, Roorkee.

*5. ‘‘Stub Column Tests on Indian Standard H-Beams’’, Journal of the Institution of Engineers (India), Volume 51, No. 11, C.I. 6, July, 1971.

*6. ‘‘Kani’s Iteration Method I-Analysis of Continuous Beams’’ The Indian Engineer, Volume XIV, No. 6 June, 1970.

*7. ‘‘Kani’s Iteration Method II Analysis of Frames’’, The Indian Engineer’’, Volume XIV, No. 8 August, 1970.

*8. Hinge Formation in Plane Frames Considering Finite Deformations All India Conference on ‘‘Tall Buildings’’ The Institution of Engineers (1) Roorkee Local Centre, March 1-3, 1993.

**9. ‘‘Design, Construction and Behaviour Aspects of Concrete and Steel Structures’ Recent Trends in Civil Engineering National Seminar, Jodhpur, February 22-23, 2002, Depart-ment of Civil Engineering MBM Engineering College, Faculty of Engineering, JN Vyas University, Jodhpur pp 229.

**10. ‘Corrosion of Reinforcing Steel Bars in Concrete’ Futuristic Construction Materials and Technique (FCMT-2004, Feb. 21-22, 2005) Department of Structural Engineering Faculty of Engineering, JN Vyas University Jodhpur.

**11. ‘Stresses in Reinforcing Steel Bars, HYSD of Grade Fe 415’ Futuristic Construction Materials and Technique (FCMT 2004, Feb. 21-22, 2005) Department of Structural Engineering Faculty of Engineering, JN Vyas University, Jodhpur.