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A CRITICAL COMPARATIVE STUDY OF IS 800-2007ANDIS 800-1984-2

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A CRITICAL COMPARATIVE STUDY OF IS 800-2007ANDIS 800-1984-2 Powered By Docstoc
					   INTERNATIONAL JOURNAL and Technology (IJCIET), ISSN 0976 – 6308
International Journal of Civil Engineering OF CIVIL ENGINEERING AND
                            TECHNOLOGY July-August
(Print), ISSN 0976 – 6316(Online) Volume 4, Issue 4, (IJCIET) (2013), © IAEME


ISSN 0976 – 6308 (Print)
ISSN 0976 – 6316(Online)                                                      IJCIET
Volume 4, Issue 4, July-August (2013), pp. 36-54
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     A CRITICAL COMPARATIVE STUDY OF IS:800-2007ANDIS:800-1984

                                  Dr.T.Muralidhara Rao1, S.S.Phani2
               1
                  Professor, Dept.of Civil Engg., CVR College of Engineering, Hyderabad
              2
                  Deputy Executive Engineer, Tirumala Tirupati Devasthanam, Hyderabad.



ABSTRACT

         Now-a-days, the whole world is changing over to limit state method since it is more rational.
The latest version of the Code of Practice for general construction in steel IS: 800-2007 is based on
Limit State Method of design. The design concept is totally changed in comparison to earlier code IS
800:1984 which is based on Elastic method. In view of this, an effort has been made to high light the
critical comparison between the important clauses of IS:800-2007 and IS:800-1984. At a glance, the
present study will provide the readers a quick and clear idea about the changes in the corresponding
clauses of old(IS:800-1984) and new (IS:800-2007) codes of practice.

Keywords: IS 800:1984, IS 800: 2007, Critical Comparison, Limit state method, Working stress
method.

INTRODUCTION

        Codes of practice provide the minimum requirements that a design has to satisfy. In India,
Bureau of Indian Standards (B.I.S.) is the statutory body that publishes the codes of practice to be
followed in the Indian Professional practice. Though the codes of practices issued by B.I.S. are
revised after 20 to 25 years, the second revision of IS 800 was published in 1984. The third revision
of the code was released after about 24 years, in December 2007, by the B.I.S. The material
contained in the code reflects the state-of-the-art of knowledge and is based on the provisions in
other international codes as well as other research publications. This version of the code is based on
the Limit state method of design philosophy whereas the earlier version was based on Working stress
method.
        The revised Code IS:800-2007 will enhance the confidence of designers, engineers,
contractors, technical institutions, professional bodies and the industry will open a new era in safe
and economic construction in steel.



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International Journal of Civil Engineering and Technology (IJCIET), ISSN 0976 – 6308
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MAJOR MODIFICATIONS

In the latest revision of IS: 800, the following major modifications have taken place:
 a) The standard is based on limit state method, reflecting the latest developments and the state of
     the art.
 b) In view of the development and production of new varieties of medium and high tensile
     structural steels in the country, the scope of the standard has been modified permitting the use of
     any variety of structural steel provided the relevant provisions of the standard are satisfied.
 c) The standard has made reference to the Indian Standards now available for rivets, bolts and other
     fasteners.

Codal Provisions
The code is divided into the following 17 Sections. It also contains seven appendices.
a) Contents
     1. General 2. Materials 3. General Design Requirements 4. Methods of Structural Analysis
     5. Limit State Design 6. Design of Tension Members 7. Design of Compression Members
     8. Design of Members subjected to Bending 9. Member subjected to combined forces
     10. Connections 11. Working Stress Design 12. Design and Detailing for Earthquake Loads
     13. Fatigue 14. Design Assisted by Testing 15. Durability 16. Fire Resistance 17. Fabrication
     and Erection
b) It also includes the following Annexure
     A: List of referred Indian Standards B: Analysis and design methods
     C: Design against floor vibration D: Determination of effective length of
     columns
     E: Elastic lateral torsional buckling F: Connections
     G: General recommendations for Steelwork Tenders and Contracts
     H: Plastic properties of beams
c) General Design Requirement
    • The new edition of IS: 800 clearly classify cross sections as to, Plastic, Compact, Semi-
        Compact or Slender. Separate design procedures have been laid down for each type of
        classification.
    • The classification has been made based on each element of the section involved and depends
        on the ratio of the major and minor dimension of the element i.e., limiting width to thickness
        ratio.
d) Limit States Method of Design
    • Separate Partial Safety Factors for different loads and combinations are considered based on
        the probability of occurrence of the loads. Similarly different safety factors for materials are
        also considered depending on perfection in material characteristics and fabrication/ erection
        tolerances.
    • Different permissible deflections considering different material of construction have also
        been proposed.
e) Tension Members
    • Tension members have been designed by considering not only failure of the net cross section
        (after taking Shear Lag) but also considering yielding of the gross cross section and rupture
        of the section at the joint.
f) Compression Members
    • Design of Compression members considers the appropriate buckling curve out of total four
        numbers depending on the type of section and the axis of buckling. Earlier version of the


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       Working Stress Method of design considered only one buckling curve for all types of
       members irrespective of the nature of buckling.
g) Members Subjected To Bending
    • Reduction in Flexure capacity due to high Shear Force has been elaborated in detail.
    • New version introduces tension field design of plated steel girders.
h) Members Subjected To Combined Forces
    • Moment Gradient across a member / element considered in detail, while designing against
       combined action of axial force and bending moment in an element of a structure.
i) Working Stress method of Design
    • Working Stress Method (WSM) of Design has been kept in a separate chapter with minor
       modifications (compared to the earlier code) and in tune with the specifications of the new
       code to ensure smooth transition from WSM to LSM for Practicing engineers and
       Academicians whosoever desires.
j) Design Against Fatigue
    • Design against fatigue has been introduced for the first time. The state-of-art concept of stress
       range has been introduced for the first time in this code, this code automatically supersedes
       IS:1024 for steel structures which considered the stress–ratio method.
k) Earthquake Resistance
    • Response Reduction factor has been introduced and elaborated in the new edition for the first
       time.
    • Comparing the provisions of the 1984 version of the code with that of the present code, it is
       seen that the present code contains major revisions.

Comparison of Critical Parameters/Clauses of IS:800-2007 and IS: 800-1984
        In the newly revised IS: 800, stress is laid to make optimum utilisation of the structural
member along with provision of making adequate checks for restricting local buckling. Comparison
of the critical parameters/clauses of two versions of the code (i.e. IS: 800-2007 and IS: 800-1984) is
as follows:


 S.No.        Clause               IS:800-2007                     IS:800-1984          Comments

1.0       Material
1.1       Structural       Table-1(Pg.14)                   Clause: 2.1(Pg.21)
          Steels           All the structural steels used   All structural steels used in No change.
                           in general construction,         general construction
                           coming under the purview         coming under the purview
                           of this standard shall           of this coded shall confirm
                           conform to IS:2062 before        to IS:2062, before
                           fabrication.                     fabrication.
                           Structural steel other than      Structural steel other than
                           that specified in IS 2062 can    those specified in
                           be used provided that the        clause:2.1 may also be
                           permissible stresses and         used provided that the
                           other design provisions are      permissible stresses and
                           suitably modified and the        other design provisions are
                           steel is also suitable for the   suitably modified and steel
                           type of fabrication adopted.     is also suitable for the type
                                                            of fabrication adopted.
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1.2     Fasteners /    Clause 2.3,Pg.12-15            Clause:2.2,2.5,2.6,Pg.21-
        Rivets/                                       22                             ---
        Bolts/Nuts     Rivets made from steel shall   Rivets shall conform to
                       conform to IS:7557 or 2062     IS:1929-1961 and
                       as appropriate. High           IS:2155-1962 as
                       Tension Steel rivets shall     appropriate. High tension
                       conform to IS:1149.            steel rivets, if used, shall
                                                      me manufactured from
                                                      steel conforming to
                       Bolts, Nuts and Washers        IS:1149.
                       shall conform to the           Bolts, Nuts shall conform
                       recommendations of IS:         to IS:1363-1967, IS:1364-
                       4000.                          1967, IS:1367-1967,
                                                      IS:3640-1967, IS:3757-
                                                      1972, IS:6623-1972 and
                                                      IS:6639-1972 as
                                                      appropriate. Washers shall
                                                      conform to IS:5369-1975,
                                                      IS:5370-1969, IS:5372-
                                                      1975, IS:5374-1975,
                                                      IS:6610-1972 and
                                                      IS:6649-1972 as
                                                      appropriate.

2.0     General Design Requirements
2.1     Load          Clause:3.5(Pg.16)               Clause:3.4.2(Pg.24)
        Combination 1) DL + IL                        1) DL + IL                     Importance
                      2) DL+ IL + WL or EL            2) DL+IL+WL or EL              is also given
                      3) DL + WL or EL                3) DL + WL or EL               to the
                      4) DL + ERL                                                    erection
                      DL-Dead Load                    DL-Dead Load                   loading in
                      IL-Imposed Load                 IL-Imposed Load                deciding
                      WL-Wind Load                    WL-Wind Load                   critical load
                      EL-Earthquake Load              EL-Earthquake Load             combination.
                      ERL-Erection Load

2.2     Section        Clause:3.7(Pg.17)
        Classification Sections are classified based No such classification has      The Class of
                       on its local buckling          been made.                     section
                       strength and the ability to                                   governs its
                       allow rotation before failing.                                design.
                       They are
                       a) Class 1 (Plastic)
                       b) Class 2 (Compact)
                       c) Class 3(Semi-compact)
                       d) Class 4 (Slender)




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2.3     Increase of   Clause:5.3.3(Pg.29)              Clause:3.9(Pg.31)
        Stresses      Partial safety factors have to   If Wind / Earthquake           Partial safety
                      be considered and no             Loads are considered,          factors are
                      increase or decrease of          permissible stresses in        considered
                      stresses have to be              structural steel and steel     for loads
                      considered for individual        castings shall be increased    instead of
                      loads.                           by 33.33%.                     increasing the
                                                       If Wind / Earthquake           permissible
                                                       Loads are considered,          stresses.
                                                       permissible stresses in
                                                       rivets, bolts and nuts shall
                                                       be increased by25%.
                      Clause:5.5.1(Pg.30)              Clause:3.12(Pg.34)
2.4     Stability     Structure should satisfy two     Restoring moment>1.2           Importance
                      limit states                     xmax. Overturning              is given to
                      1. Limit state of strength       moment(due to DL) + 1.4        serviceability
                      2. Limit state of                times max. Overturning         requirements
                      serviceability                   moment (due to IL and          in deciding
                      The structure should adhere      WL/EL)                         structures
                      toa) Stability against                                          stability in
                      Overturning.                     In cases where DL              addition to
                      The loads and effects            provides the restoring         the strength
                      Contributing to the              moment, only 0.9 times         requirement.
                      resistance shall be              DL shall be considered.
                      multiplied with 0.9 and
                      added together to get
                      design resistance
                      (after multiplying with
                      appropriate partial safety
                      factor).
                      b) Sway Stability.
2.5     Limiting      Clause:5.6.1(Pg.31)              Clause:3.13(Pg.34)
        Deflection    Deflection limits have been      Max. Deflection for all        Importance
                      provided separately for          applicable loads (Vertical     is given to
                      Industrial buildings and         / Horizontal ) = l / 325 of    serviceability
                      other buildings and separate     the span.                      requirements
                      limits have been mentioned                                      for various
                      for different members.                                          members in
                                                                                      a structure.
3.0     Tension Members
3.1     Axial       Clause:6.1(Pg.32-34)               Clause:4.1(Pg.37)
        Stresses    Design strength of a tension       Stress on the net effective    Additional
                    member should be least of          area not to exceed             provision
                    *Strength due to yielding          σ at = 0.6 f y (MPa).          for block
                    of gross c/s                                                      shear has
                    *Strength due to rupture of                                       been
                    critical c/s                                                      incorporated.
                    *Strength due to block
                    shear

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3.2     Maximum         Clause:3.8(Pg.20)                      Clause:3.7,Table                No change.
        Slenderness     *Tension member(other                  3.1(Pg.30)
        Ratio           than pre-tensioned) = 400              *Tension member (other
                        *Tension Member =180                   than pre-tensioned)= 400
                        (reversal of stress due to             *Tension Member = 180
                        loads other than WL or EL)             (reversal of stress due to
                        *Tension member = 350                  loads other than WL or
                        (reversal of stress due to             EL)
                        WL or EL)                              *Tension member =
                                                               350(reversal of stress due
                                                               to WL or EL)
3.3     Design          Clause:6.2,6.3&6.4(Pg.32-              Clause:4.2(Pg.37)               Partial safety
        strength and    34)                                    Design strength P = σ at Anet   factors have
        net effective   Design strength shall be               Single angle connected          introduced.
        area            minimum of Tdg , Tdn , Tdb .           through one leg:
                        Where,                                  Anet = A1 + A2 k , where,
                        Tdg =Strength in axial                          3 A1
                                                                k=
                        tension governed by                          3 A1 + A2
                        yielding of gross section              Pair of angles(single tee)
                         = Ag f y γ m 0                        back-to-back connected by
                        Tdn =Strength of plate in              one leg of each angle to
                        axial tension governed by              the same side of a gusset:
                        rupture of net cross                    Anet = A1 + A2 k , where,
                        sectional area at holes                         5 A1
                                                                k=
                         = 0.9 An f u γ ml                           5 A1 + A2
                        Tdn =Rupture strength of an
                        angle connected through                 Double angles or tees
                        one leg governed by rupture             back-to-back connected to
                        at net section                          each side of a gusset :
                        = 0.9 Anc f u γ ml + β Ago f y γ m 0    If the angles are connected
                                                                by tacking rivets along
                                                                their length at a pitch not
                        Tdb = strength of connection
                                                                exceeding 1.0m, then the
                        governed by block shear at              effective area shall be
                        an end connection of plates taken equal to the gross
                        and angles=                             area minus the deduction
                        [ Avg f y ( 3 γ m0 ) + 0.9Atn fu γ ml ] for holes.
                                   (OR)                         Double angles or tees
                                                                back-to-back connected to
                        Tdb =[0.9A fu ( 3γml ) + A fy γm0]
                                   vn                tg         each side of a gusset :
                                                                If the angles are not tack
                        Where,                                  riveted using a pitch not
                         f y = yield stress of material exceeding 1.0m, then each
                        Ag =gross area of cross                 angle shall be designed as
                                                                a single angle connected
                                Section
                                                                through one leg and
                        γ m0 =partial safety factor for effective sectional area

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                       failure in tension by                  shall be calculated using
                       yielding=1.10                           Anet = A1 + A2 k , where,
                       γ ml =partial safety factor for                 3 A1
                       failure at ultimate                    k=
                                                                    3 A1 + A2
                       stress=1.25
                        f u = ultimate stress of the
                       material                                       Where A1 =Effective cross
                        Anc = net area of the                         sectional area of connected
                       connected leg                                  leg (or flange of tee)
                        Ago = gross area of the                        A2 = Gross area of
                        outstanding leg                               outstanding leg (or web of
                       β =1.4−0.076(wt)(ft fu)(bs L ) ≤(fuγm0 fyγml ) the tee)
                                                   c

                       ≥ 0.7
                       Where,
                       w = outstand leg width
                       bs = shear leg width
                      Lc = length of the end
                     connection(i.e., distance
                     between outermost bolts in
                     the end joint measured
                     along the load direction or
                     length of the weld along the
                     load direction)
                      Avg , Avn = minimum gross
                     and net area in shear along
                     bolt line parallel to external
                     force respectively
                      Atg , Atn = minimum gross
                     and net area in tension from
                     the bolt hole to the toe of
                     the angle, end bolt line,
                     perpendicular to the line of
                     force respectively.
4.0     Compression Members
4.1     Design       Clause:7.1.2 (Pg.34)                     Clause:5.1.1, IS:800-2007             Partial safety
        strength     Design compressive                       Design strength,                      factors and
                     strength, Pd = Ac f cd                   Pd = Agσ ac ≤ 0.6 f y nor             imperfection
                                                                                                    factors (based
                       Where, Ac = effective                 the permissible stress σ ac
                                                                                                    on buckling
                       sectional area (i.e., gross           Where, Ag = gross                      class) have
                       sectional area-deduction for sectional                                       been
                       rivets/bolts holes area)                                  Area               introduced
                        f cd =design compressive                                   f cc f y         for design
                       Stress =                              σ ac = 0.6                     n       compressive
                                                                        [( f cc ) + ( f y ) ]1/ n
                                                                                 n
                                    f y γ m0                                                        stress.
                        f cd =                     = χ fy γ m ≤ fy γm
                               φ + [φ 2 − λ 2 ]0.5
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                                                            Where,
                      Where,                                σ ac =permissible stress in
                      φ = 0.5[1 + α (λ − 0.2) + λ 2 ]       axial compression(MPa)
                      λ = non-dimensional                    f y =yield stress of steel
                      effective                             (MPa)
                      slenderness ratio                      f cc =elastic critical stress
                                                  2
                      =   f y f cc =   f y ( KL r ) π 2 E
                                                                                 π 2E
                      f cc = Euler buckling stress          in compression =
                                                                                  λ2
                       = π 2 E ( KL r )
                                        2
                                                             E =modulus of elasticity
                                                            of
                      Where,
                                                            steel ( 2 × 105 MPa )
                       KL r =effective slenderness
                                                            λ = ( l r ) =slenderness
                      ratio or ratio of effective
                      length, KL to appropriate             ratio
                      radius of gyration, r                  of the member
                      α =imperfection factor                n =a factor assumed as 1.4
                          =0.21 for buckling class
                      ‘a’
                          =0.34 for buckling class
                      ‘b’
                          =0.49 for buckling class
                      ‘c’
                          =0.76 for buckling class
                      ‘d’
                       χ =stress reduction factor
                      (Table 8, IS:800-2007) for
                       different buckling class,
                      slenderness ratio and yield
                      stress
                                            0.5
                      = 1 [φ + (φ 2 − λ 2 ) ]
4.2     Axial         Clause:7.1.2.1(Pg.34)                 Clause:5.1(Pg.38)
        stresses      Allowable axial stress or             Direct stress in                 Concept of
                      design compressive stress             compression shall not            imperfection
                      (fcd) shall be calculated             exceed 0.6fy or as               factor and
                      using the formulas given in           calculated by equation           buckling
                      the clause or can be                  given in Cl. 5.1.1.              class of the
                      calculated using Tables               Permissible stress σ ac shall    section has
                      9(a),9(b),9(c),9(d) on the            be taken from Table-             been
                      basis of buckling class of            5.1(Pg.39) for                   introduced.
                      the section.                          corresponding slenderness
                                                            ratio.
4.3     Effective     Clause:7.2(Pg.35-45)                  Clause:5.2(Pg.38)
        Length (l),   ‘K’ values shall be taken             ‘K’ values shall be taken        ‘K’ values
        l = KL        appropriately based on                appropriately based on           given in both
                      degree of end restraint of            degree of end restraint of       the codes are
                      member as given in Table-             member as given in Table-        same.
                      11(Pg.45).                            5.2 (Pg.41&42) or follow
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                                                   the procedure given in
                                                   Appendix-C.
                      Trusses and braced frames    Trusses and braced frames
                      buckling in the plane of     buckling in the plane of
                      truss, effective length ‘1’  truss, ‘l’ shall be taken as
                      shall be taken as between    between 0.7 and 1.0 times
                      0.7 and 1.0 times the        the distance between the
                      distance between the centres centres of intersections,
                      of intersections,            depending on degree of
                      depending on degree of end end restraint.
                      restraint.
                      For members buckling in      For members buckling in
                      the plane perpendicular to   the plane perpendicular to
                      truss, ‘1’ shall be taken as truss, ‘l’ shall be taken as
                      distance between centres of distance between points of
                      intersection.                restraint.

4.4     Maximum       Table 3,Clause:3.8(Pg.20)        Clause:3.7(Pg.30)
        Slenderness   Compression member=180           Compression member=180 No change.
        Ratio         (subjected to DL and IL)         (subjected to DL and IL)
                      Compression member=250           Compression member=250
                      (subjected to WL and EL)         (subjected to WL and EL)

4.5     Built up      Clause:7.6(Pg.48-50)             Clause:5.7.2(Pg.47)
        Members       Lacing of compression            Lacing of compression        No change
        with Lacing   member shall be designed         member shall be designed      in the load
                      for a transverse shear equal     for a transverse shear       calculations
                      to at least 2.5 % of the axial   equal to at least 2.5 % of   and basic
                      force in the member.             the axial force in the       design
                                                       member.                      requirements.
                      Slenderness ratio of the         Slenderness ratio of the
                      lacing bars shall not            lacing bars shall not
                      exceed 145.                      exceed 145.
                      Angle of inclination with        Angle of inclination with
                      the axis of 400 to 700 to the    the axis of member 400 to
                      axis of built up section         700.(for both single &
                      member(for both single&          double lacing)
                      double lacing).                  Max. spacing of lacing
                      Max. spacing of lacing shall     shall be such that min.
                      be such that min.                slenderness ratio (l/r) of
                      slenderness ratio (l/r)of the    the components of the
                      components of the member         member between
                      between consecutive              consecutive connection is
                      connection is not greater        not greater than 50 or 0.7
                      than 50 or 0.7 times the         times the most
                      most unfavourable (l/r) of       unfavourable (l/r) of the
                      the member as a whole,           member as a whole,
                      whichever is less.               whichever is less.


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4.6     Built up       Clause:7.7(Pg.50-52)                        Clause:5.8(Pg.51)
        Members        Battens shall be designed to                Battens shall be designed       No changes
        with Battens   carry the bending moment                    to carry the bending            have been
        /Tie plates    &shears arising from                        moment & shears arising         made in the
                       transverse shear force ‘V’ of               from transverse shear force     load
                       2.5 % of the total axial force              ‘V’ of 2.5 % of the total       calculation
                       on the whole comp.                          axial force on the whole        and basic
                       member, at any point in the                 comp. member, at any            design
                       length of the member,                       point in the length of the      requirements.
                       divided equally between                     member, divided equally
                       parallel planes of battens.                 between parallel planes of
                       Spacing of battens centre to                battens
                       centre of end fastenings                    Spacing of battens centre
                       shall be such that the                      to centre of end fastenings
                       slenderness ratio (l/r)of the               shall be such that the
                       lesser main component over                  slenderness ratio(l/r) of the
                       that distance shall be not                  lesser main component
                       greater than 50 or greater                  over that distance shall be
                       than 0.7 time the                           not greater than 50 or
                       slenderness ratio of the                    greater than 0.7 time the
                       member as a whole, about                    slenderness ratio of the
                       its x-xaxis. (axis parallel to              member as a whole, about
                       the battens)                                its x-x axis. (axis parallel
                                                                   to the battens)
4.7     Column Base Clause:7.4(Pg.47)                              Clause:5.4(Pg.44)               The concept
        Plate       Minimum thickness of slab                      Minimum thickness of            of effective
                    base under axial                               slab base shall be              area for load
                    compression shall be                           t = 3.0w(a 2 − 0.25b2 ) σ bs    transfer has
                       t s = 2.5w( a 2 − 0.3b 2 )γ m 0 f y > t f                                   been
                                                                   Where,                          introduced.
                       Where,                                       w =pressure or loading on
                        w =uniform pressure from                   the underside of the
                       below on the slab base                      base(MPa)
                       under                                        a , b = larger and smaller
                        the factored load axial
                                                                   projection, respectively of
                       compression(MPa)
                                                                   the slab base beyond the
                        a , b = larger and smaller
                                                                   rectangle circumscribing
                       projection, respectively of                 the column(mm)
                       the slab base beyond the                    t = slab thickness (mm)
                       rectangle circumscribing the
                                                                   σ bs =permissible bending
                       column(mm)
                       t f = flange thickness of                   stress in slab base(for all
                                                                   steels assumed as
                       compression member (mm)                     185MPa)
                        f y = yield strength of steel.
                       γ m 0 = partial safety factor
                       against yield stress and
                       buckling.


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5.0     Members subjected to bending
5.1     Bending      Clause:8(Pg.52-59)                Clause:6.2(Pg.55)              ---
        Stress       Laterally Supported               Max. permissible stress,
                     Beams: Design strength in         σ bt orσ bc = 0.66fy (For
                     bending shall be calculated       strong &weak axis
                     as per the formulas given on      bending)
                     the basis whether the section
                     is susceptible to shear           Max. permissible stress
                     buckling before yielding.         σ bt orσ bc forI-beams&
                     Laterally Unsupported
                     Beams: Design strength in         Channels (based on
                     bending shall be calculated       section properties andl/ry )
                     as per the formulas given         shall be referred from
                     and resistance to lateral         Table-6.1A to 6.1F(Pg.-
                     torsional buckling should         57-62) as appropriate.
                     not be checked for                For beams & plate girders,
                     a) bending is about minor         max. permissible σ bc shall
                     axis                              be computed as per
                     b) Section is hollow or a         equation given in Cl.
                     solid bar                         6.2.3(Pg.56) or Table-
                     c) In case of major axis          6.2(Pg.64) may be referred
                     bending, the non                  for σ bc calculated from
                     dimensional                       fcbfor different values of
                     slenderness ratio is              fy.(All stresses in MPa)
                     less than 0.4.
5.2     Bearing      Clause:8.7.4(Pg.67)               Clause:6.3(Pg.68)              The partial
        Stress       Should be less than the yield     Max. permissible bearing       safety factors
                     stress of the steel divided by    stress on net area of          are based on
                     Partial safety factor i.efy/1.1   contact, σ p = 0.75 ƒy         the values
                                                                                      given in Euro
                                                                                      code.
5.3     Shear          Clause:8.4(Pg.59-60)            Clause:6.4(Pg.68)              ---
        stresses       Nominal plastic shear           Max. permissible Shear
                       resistance under pure shear     stress, τ vm = 0.45 ƒy
                       should be calculated using
                       the formulas Vn = V p , and     Average shear stress in
                              Av f yw                  member calculated on the
                       Vp =         based on the       cross section of the web
                                3                      shall not exceed the limits
                       shear are as specified for      as mentioned in Cl.
                       various sections.               No.6.4.2 (Pg.69). Also
                       Resistance to shear buckling    refer Table-6.6A, B, C
                       can be verified based on the    (Pg.73-75) for stiffened
                       value of ratio of depth to      webs.
                       web thickness. Two
                       methods have been
                       specified for calculation
                       of nominal shear strength.
                       They are

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International Journal of Civil Engineering and Technology (IJCIET), ISSN 0976 – 6308
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                         * Simple Post Critical
                         Method (can be used
                         for beams with or
                         without intermediate
                         transverse Stiffeners
                         *Tension Field Method
                         (can be used for beams
                          with intermediate
                         transverse stiffeners)
5.4     Effective        Clause:8.6.1.2(Pg.64)                                   Clause:6.6(Pg76)&Clause:          ---
        length of        No specific criteria are                                3.7(Pg.30)
        compression      mentioned.                                              To calculate permissible
        flanges &        But in order to avoid                                   bending stress as
        max.             buckling of the compression                             explained above in 5.1,
        slenderness      flange in to the web, the                               appropriate effective
        ratio            web thickness shall satisfy                             length shall be considered
                         the criteria’s specified.                               referring this clause.
                                                                                 *Max. Slenderness ratio
                                                                                 for Compression flange of
                                                                                 beam =300 Cl.3.7, Pg.3.1
                                                                                 *For Cantilever beams of
                                                                                 projecting length ‘L’,
                                                                                 referCl. No. 6.6.3, Pg.77.
6.0     Combined stresses
6.1     Axial        Clause:9.3.1&9.3.2.2       Clause:7.1.1(Pg.90)                                                Separate
        Compression (Pg70-71)                                                                                      governing
        & Bending    Members subjected to       σac,cal                   σ
                                                                                     
                                                                                                                  equations
                                                           +[( C .σ ) σ 1− ac,cal ]
                     combined axial compression  σac  mx bcx,cal bcx   0.6 fccx 
                                                                          
                                                                                     
                                                                                                                  are specified
                     and biaxial bending should                            σac,cal                             for different
                                                                                      
                     satisfy the relationship:  +[( Cmy .σbcy,cal ) σbcy 1−        ]                           types of
                                                                                    
                                                                                                   0.6 fccy 
                                                                                                                 sections.
                         ( P P ) + K (C
                             dy     y   my   My Mdy ) + KLT ( Mz Mdz ) ≤1.0
                                                                                 ≤ 1.0
                         ( P P ) +0.6Ky (CmyMy   Mdy ) +Kz ( Cmz Mz Mdz ) ≤1.0      σ       
                                                                                 If  ac,cal  〈 0.15 , the
                              dz

                         Where,                                                      σ ac 
                         C my , Cmz =equivalent                                  following equation shall
                         uniform moment factor as                                be satisfied in lieu of the
                         per Table 18                                            above.
                          P =applied axial
                         compression under factored  σ ac,cal   σ bcx ,cal   σ bcy ,cal 
                                                              +            +
                                                                                             ≤ 1.0
                                                                                             
                         load.                        σ ac   σ bcx   σ bcy 
                          M y , M z =maximum         σ ac ,cal = calculated average
                         factored applied bending    axial compressive stress.
                         moments about y and z axis σ bc ,cal = calculated bending
                         of the member.              compressive stress in
                          Pdy , Pdz =design strength extreme fibre.
                         under axial compression     σ ac = permissible axial

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International Journal of Civil Engineering and Technology (IJCIET), ISSN 0976 – 6308
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                      governed by buckling about                 compressive stress in
                      minor( y ) and major ( z )                 member subject to axial
                      axis                                       compressive load.
                      M dy , M dz =design bending                σ bc = permissible bending
                      strength about y (minor) or                compressive stress in
                                                                 extreme fibre.
                       z (major) axis considering
                      laterally unsupported length                f cc = elastic critical stress
                      of the cross section.                                             π 2E
                                                                 in compression =
                      K y = 1 + ( λ y − 0.2 ) n y ≤ 1 + 0.8n y                           λ2
                      K z = 1 + ( λz − 0.2 ) nz ≤ 1 + 0.8nz       x, y =represent x-x and y-y
                      Where,                                     planes.
                       n y , nz =ratio of the actual             Cm = 0.85 when side sway
                      applied axial force to the                 prevented.
                      design axial strength for                  Cm = 0.6 − 0.4 β ≥ 0.4
                      buckling about y and z                     when side sway is
                      axis.                                      prevented and not
                      CmLT =equivalent uniform                   subjected to transverse
                                                                 loading between their
                      moment factor for lateral
                                                                 supports in the plane of
                      torsional buckling as per
                                                                 bending.
                      Table 18 corresponding to
                      the actual moment gradient
                      between lateral supports
                      against torsional
                      deformation in the critical
                      region under consideration.
6.2     Axial         Clause:9.3.1 &                             Clause:7.1.2(Pg.90)                        Separate
        Tension       9.3.2.1(Pg.70-71)                          Member should satisfy the                  governing
        & Bending     The reduced effective                      following condition.                       equations
                      moment, M eff , under                       σat,cal   σbtx,cal   σbty,cal       are specified
                                                                           +          +
                                                                  0.6 f   0.66 f   0.66 f       ≤1.0 for different
                      tension and bending should                        y          y          y

                      not exceed the bending                                                                types of
                      strength due to lateral                                                               sections.
                                                                 Where,
                      torsional buckling, M d .                  σ at ,cal =calculated average
                      M eff = [ M − (ψ TZ ec A )] ≤ M d          axial tensile stress
                      Where,                                     σ bt ,cal =calculated bending
                       M , T = factored applied                  tensile stress in extreme
                      moment and tension                         fibre
                      A=area of cross section                     x, y =represent x-x and y-y
                       Z ec = elastic section                    planes
                      modulus of the section w.r.t.
                      extreme compression fibre
                      ψ =0.8, if T and M can vary
                      independently or
                      otherwise=1.0


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International Journal of Civil Engineering and Technology (IJCIET), ISSN 0976 – 6308
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6.3     Bending &       Clause:9(Pg.69-70)             Clause:7.1.4(Pg.91)                                   The moment
        Shear           Moment carrying capacity       Equivalent stress                                     reduction is
                        of the section shall be        calculated by the equation                            dictated by
                        reduced by the amount as       given in this clause shall                            the
                        specified in the code (for     not exceed the value,                                 percentage
                        high shear force).             σ e = 0.9 f y .                                       of shear
                        No reduction is required for                                                         force w.r.t.
                        Shear force value < 60% of                                                           allowable
                        allowable shear capacity of                                                          shear force
                        the section.                                                                         in the section.
6.4     Bearing,        No specific criteria are       Clause:7.1.5(Pg.92)                                   ---
        Bending &       mentioned.                     Equivalent stress
        Shear                                          calculated using the
                                                       equation
                                                                 2        2
                                                                                                 τ2 ,
                                                       σe,cal = σbt,cal +σp,cal +σbt,calσp,cal +3 vmcal
                                                                            (OR)
                                                                  2          2
                                                       σe,cal = σ bc,cal                            τ2 ,
                                                                           +σp,cal +σbc,calσp,cal +3 vmcal
                                                       shall not exceed the value,
                                                       σ e = 0.9 f y .
7.0     Connections
7.1     Bolted
7.1.1   Permissible     Clause:10(Pg.73-77)            Clause:8.9.4(Pg.95),                                  ---
        Stresses for    No specific value is           Table 8.1
        bolts           prescribed. Procedure given    a) Axial tension 120 MPa
                        for calculation of             b) Shear 80 MPa
                        permissible loads (Axial       c ) Bearing 250 MPa
                        Tension, Shear &Bearing).
7.1.2   Combined        Clause:10.4.6(Pg.77)           Clause:8.9.4.5(Pg.96)                                 ---
        shear and       No specific value is           Individual stresses should
        tension in      provided. Procedure given      not exceed allowable
        bolts           for calculation of             values and combined
                        permissible loads.             stress ratio should not
                                                       exceed 1.40.
7.1.3   Minimum         Clause:10.2.2(Pg.73)           Clause:8.10.1(Pg.96)                                  No change
        pitch           Shall not be less than 2.5     Shall not be less than 2.5                            has been
                        times the nominal diameter     times the nominal                                     made.
                        of the fastener (Bolt/Rivet)   diameter of the bolt.
7.1.4   Minimum         Clause:10.2.4.2(Pg.74)         Clause:8.10.2(Pg.97)                                  Not much
        edge distance   Should be >1.7 times hole      Table 8.2                                             variation is
                        dia. for sheared or hand-      Distance from the centre                              observed in
                        flame cut edges, &>1.5         of any hole to the edge of                            the end
                        times hole dia. for rolled,    a plate shall not be less                             results.
                        machine-flame cut, sawn        than that specified in Table
                        and planed edges, from         8.2.
                        the centre of the hole.        When two or more parts
                                                       are connected together, a
                                                       line of bolts shall be
                                                       provided at a distance of
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International Journal of Civil Engineering and Technology (IJCIET), ISSN 0976 – 6308
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                                                        not more than 37 mm+4t
                                                        from the nearest edge,
                                                        where t is the thickness of
                                                        thinner outside plate in
                                                        mm.
                                                        In case of work not
                                                        exposed to weather, this
                                                        may be increased to 12t.
7.1.5     Maximum       Clause:10.2.3(Pg.74)            Clause:8.10.1(Pg.96)          No change
          pitch         Shall not exceed 32t or         Shall not exceed 32t or       has been
                        300mm whichever is less,        300mm whichever is less,      made.
                        where t is the thickness of     where t is the thickness of
                        the thinner outside plate.      the thinner outside plate.
7.1.6     Maximum       Clause:10.2.4.3(Pg.74)          No specific criteria are      ---
          edge distance Shall not exceed 12tε ,         mentioned.
                        where t is the thickness of
                        the thinne router plate, and ε
                        = (250/fy)1/2
7.1.7     Clearance for Clause:10.2.1(Pg.73)           Clause:3.6.1.1(Pg.28)          More
          fastener      As given in Table 19           1.5 mm in excess of the        practical
          Holes                                        nominal diameter of the        aspect for
                                                       bolt irrespective of the       clearance
                                                       diameter of the bolt, unless   has been
                                                       otherwise specified.           considered.
7.2       Welded
7.2.1     Fillet welds
7.2.1.1   Permissible   Clause:10.5(Pg.78)             Clause:8.9.4.7, IS:800-        ---
          stresses      Shear stress shall not exceed 1984Clause:7.1.2 IS:816-
                        110MPa nor as calculated       1969(Pg.17)
                        using clause 10.5.7(Pg.79-     Shear stress shall not
                        81)                            exceed 110 MPa.
7.2.1.2   Effective     Clause:10.5.3(Pg.78)           Clause:8.9.4.7, IS:800-        No Changes
          throat        Shall not be < 3mm and not 1984Clause:6.2.3,                  have been
          thickness     > 0.7t, where t is the         IS:816(Pg.10)                  suggested
                        thickness of the thinner       Shall not be < 3 mm and
                        plate. For stresses            not > 0.7t, where t is the
                        calculation in fillet welds    thickness of the thinner
                        joining faces inclined to      plate. For stresses
                        each other, effective throat   calculation, the effective
                        thickness shall be taken as    throat thickness shall be
                        K times the fillet size, where taken as K times the
                        K is a constant.               filletsize, where K is a
                                                       constant.
7.2.1.3   Effective      Clause:10.5.4(Pg.78)           Clause:8.9.4.7, IS:800-       ---
          length         Shall be the overall length    1984,Clause:6.2.4,IS:816(
                         of weld excluding end          Pg.11)
                         returns in case of Fillet      Shall be the overall length
                         welds and shall be the         of the weld plus twice the

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International Journal of Civil Engineering and Technology (IJCIET), ISSN 0976 – 6308
(Print), ISSN 0976 – 6316(Online) Volume 4, Issue 4, July-August (2013), © IAEME

                         overall length of weld         weld size.
                         including end returns for
                         Butt welds.
7.2.1.4   Effective      Clause:6.2.3(Pg.10)            Clause:8.9.4.7, IS:800-       ---
          area           Effective length times         1984, Clause:6.2.3,
          of weld        Effective throat thickness     IS:816(Pg.10)
                                                        Effective length times
                                                        effective throat thickness
7.2.1.5   Minimum        Clause:10.5.4(Pg.78)           Clause:8.9.4.7, IS:800-       No Changes
          length of                                     1984Clause:6.2.4.1,IS:816     have been
          weld           Shall not be less than four    (Pg11)                        suggested.
                         times the size of the weld.    Shall not be less than four
                                                        times the size of the weld.
7.2.1.6   Minimum        Clause:10.5.2(Pg.78)           Clause:8.9.4.7, IS:800-       No Changes
          size of the                                   1984,                         have been
          weld                                          Clause:6.2.2,IS:816(Pg.10)    suggested
                         Shall not be less than 3 mm.   Shall not be less than 3
                                                        mm nor more than the
                                                        thickness of the thinner
                         The minimum size of the        part joined.
                         first run or the single run    The minimum size of the
                         weld shall be as given in      first run or the single run
                         Table 21(Pg 78).               weld shall be as given in
                                                        Table 1 in IS:816 to avoid
                                                        risk of cracking in the
                                                        absence of preheating.
7.2.2     Butt Welds
7.2.2.1   Permissible    Clause:10.5.7(Pg.79)           Clause:8.9.4.7, IS:800-       ---
          stresses.      Stresses in weld shall not     1984, Clause:7.1.1,
                         exceed those permitted in      IS:816(Pg.16)
                         the parent metal.              Stresses in weld shall not
                                                        exceed those permitted in
                                                        the parent metal.
7.2.2.2   Minimum        Clause:10.5.2.4(Pg.78)         Clause:8.9.4.7, IS:800-
          size of weld   Size of butt weld shall be     1984, Clause:6.1.3,
                         specified by the effective     IS:816(Pg.5)
                         throat thickness.              Size of butt weld shall be
                                                        specified by the effective
                                                        throat thickness.
7.2.2.2   Effective      Clause:10.5.4(Pg.78-79)        Clause:8.9.4.7, IS:800-       ---
          area of weld   Effective length times the     1984,
                         effective throat thickness     Clause:6.1.6,IS:816(Pg.7)
                                                        Effective length times the
                                                        effective throat thickness
7.2.2.3   Effective      Clause:10.5.3.3,(Pg.78)        Clause:8.9.4.7, IS:800-
          throat                                        1984
          thickness      For complete penetration,      Clause:6.1.4,IS:816(Pg.6)
                         effective throat thickness     For complete penetration,

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International Journal of Civil Engineering and Technology (IJCIET), ISSN 0976 – 6308
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                        shall be taken as thickness     effective throat thickness
                        of thinner part joined.         shall be taken as the
                                                        thickness of thinner part
                        For an incomplete               joined.
                        penetration, effective throat   For incomplete
                        thickness shall be taken as     penetration, effective
                        the minimum thickness of        throat thickness shall be
                        the weld metal common to        taken as the thickness of
                        the parts joined, excluding     the weld metal common to
                        reinforcement.                  the parts joined, excluding
                                                        reinforcement.
8.0     Gantry Girder
8.1     Increase in     No specific criteria are        Clause:3.9.3(Pg.31)            Stresses are
        stresses        given.                          While considering              to be
                                                        simultaneous effects of        calculated
                                                        vertical & horizontal surge    using
                                                        loads of cranes for the        adequate
                                                        combination given in Cl.       Partial Safety
                                                        3.4.2.3 & 3.4.2.4, the         factors.
                                                        permissible stresses may
                                                        be increased by10 %.
8.2     Limiting        Clause:5.6.1(Pg.31)             Clause:3.13.1.3(Pg.35)         ---
        deflection      Table 6 should be referred.     Vertical deflection:
                                                        Under DL and IL shall not
                                                        exceed the following:
                                                        i. L/500, where manually
                                                        operated cranes are
                                                        operated and for similar
                                                        loads
                                                        ii. L/750, where electric
                                                        overhead travelling cranes
                                                        operated up to 50 tonnes
                                                        iii. L/1000, where electric
                                                        overhead travelling cranes
                                                        operated over 50 tonnes
                                                        iv. L/600, other moving
                                                        loads such as charging cars
                                                        etc.
                                                        L=span of the crane
                                                        runway girder.
                                                        Horizontal deflection:
                                                        At the caps of columns in
                                                        single storey buildings, the
                                                        horizontal deflection due
                                                        to lateral forces should not
                                                        exceed l / 325 of the actual
                                                        length ‘ l ’ of the column.



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International Journal of Civil Engineering and Technology (IJCIET), ISSN 0976 – 6308
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9.0     Design and Detailing for Earthquake Loads
9.1     Load            Clause:12.2 (Pg.87)             No such criteria are given.   ---
        Combination     Two more combinations
                        have to be considered
                        1) 1.2 DL + 0.5 LL ± 2.5
                        EL
                        2) 0.9 DL ± 2.5 EL
9.2     Lateral Load    The Building has been           No such classification has    ---
        Resisting       classified as                   been made
        System          1) Braced Frame System
                        a) Ordinary concentrically
                        Braced Frames (OCBF)
                        b) Special Concentrically
                        Braced Frame(SCBF)
                        c) Eccentrically Braced
                        Frame (EBF)
                        2) Moment Frame System
                        a) Ordinary Moment
                        Frame (OMF)
                        b) Special Moment
                        3) Frame (SMF)
                        Various criteria for loads on
                        members are specified for
                        different lateral load
                        resisting systems.
10.0    Fatigue
10.1    Reference      Clause:13.2.1(Pg.91)             No such criteria are          ---
        design         Conditions when fatigue          mentioned.
        Condition      design becomes necessary
                       are mentioned along with a
                       plot of standard S-N curve
                       for each category.
                       A capacity reduction factor
                       µr is to be applied when
                       plates greater than 25 mm
                       tk. Are joined by transverse
                       fillet orbutt welding.
10.2    Partial Safety Clause:13.2.3(Pg.92)             No such criteria are          ---
        Factors        Based on consequences of         Mentioned.
                       fatigue failure, component
                       details have been classified
                       and Partial Safety Factors
                       are given for each
                       type.(Refer Table 25, Pg.
                       92)
10.3    Detail         Clause:13.3(Pg.92-98)            No such criteria are          ---
        Category       Tables 26 (a) to (d) indicate    mentioned.
                       the classification of

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  International Journal of Civil Engineering and Technology (IJCIET), ISSN 0976 – 6308
  (Print), ISSN 0976 – 6316(Online) Volume 4, Issue 4, July-August (2013), © IAEME

                            different details into various
                            categories for the purpose of
                            assessing fatigue strength.
   11.0      Fire Resistance
   11.1                     Clause:13( Pg.105-110)         No such criteria are              ---
                            Following points have been mentioned.
                            discussed and relevant
                            design standards have been
                            mentioned Fire Resistance
                            Level Period of Structural
                            adequacy
                            *Variation of mechanical
                            properties of Steel with
                            Temperature
                            *Limiting Steel
                            Temperature
                            *Thermal Increase with
                            Time in Protected members
                            *Temperature increase with
                            Time in unprotected
                            Members
                            *Determination of period of
                            Structural adequacy from a
                            single test
                            *Three-Sided Fire exposure
                            condition.


CONCLUSION

           An explicit comparison of important clauses of IS:800-2007 and IS:800-1984 presented in
this paper gives a quick insight to the readers about the changes made in corresponding clauses of the
old and latest codes of practice.

REFERENCES

    1. IS 800:2007, Indian Standard Code of Practice for General Construction in Steel, Bureau of
       Indian Standards, New Delhi.
    2. IS 800:1984, Indian Standard Code of Practice for General Construction in Steel, Bureau of
       Indian Standards, New Delhi.
    3. Dr.Subramanian.N, (2008), “Code of Practice on Steel Structures - A Review of IS 800: 2007”,
       Civil Engineering & Construction Review.
    4. Dr.Subramanian.N, (2009),“Design of Steel Structures”, Oxford University Press, New Delhi.
    5. Vidula S. Sohoni and Dr.M.R.Shiyekar, “Concrete–Steel Composite Beams of a Framed
       Structure for Enhancement in Earthquake Resistance”, International Journal of Civil
       Engineering & Technology (IJCIET), Volume 3, Issue 1, 2012, pp. 99 - 110, ISSN Print:
       0976 – 6308, ISSN Online: 0976 – 6316.



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