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									    DETAILING FUNCTIONS
   DESIGN AND DESIGN REQUIREMENTS
   CUTTING   AND   BENDING     OF THE
    REINFORCEMENT
   PLACING AND WIRING IN POSITION
   MAINTAINING       POSITION      OF
    REINFORCEMENT
   PREASSEMBLY OF CAGES AND MATS
   CONCRETING
   MEASUREMENTS OF QUANTITIES
   ECONOMY IN THE USE OF STEEL
REQUIREMENTS OF
DETAILING
   SIMPLE FOR FABRICATION AND PLACING
   THE CRACK WIDTH MUST BE EITHIN
    ACCEPTABLE LIMITS UNDER SERVICE
    CONDITIONS.THERESHOULD NOT BE ANY
    FREE PATH FOR THE PROPOGATION OF
    THE    CRACKS    WITHOUT     BEING
    TRAVERSED BY THE REINFORCEMENT.
    THIS IS ACHIEVED BY LIMITING THE
    MAX SPACING OF THE REINFORCEMENT
    AND MIN AMOUNT OF REIN.
   THERE SHOULD BE SUFFICIENT
    SPACE FOR CON TO BE PROPERLY
    POURED AND COMPACTED. THIS IS
    ACHIEVED   BY   LIMITING MIN
    SPACING BET THE BARS.
   THE DETAILING SHOULD BE SUCH THAT
    THE INTERNAL FORCES ARE SAFELY
    TRANSFERRED FROM ONE MEM TO
    ANOTHER,   AND    FROM   REIN    TO
    CONCRETE.JOINTS                AND
    DISCONTINUITIES SHOULD BE CAPABLE
    OF WITHSTANDING THE SAME FORCES
    AS THE ADJOINING SECTIONS.THIS IS
    ACHIEVED BY PLACING TH EREIN IN THE
    DIR OF THE TENSILE FORCE AS FAR AS
    POSSILBLE.
   THE STRUCTURAL DRAWING SHOULD
    BE COMPLETE AND UNAMBIGOUS.BAR
    BENDING SHOULD AND NECESSARY
    INSTRUCTIONS    TO    THE    SITE
    ENGINEERS   MUST    BE    CLEARLY
    INDICATED ON THE DRAWING.
    DO’S FOR DETAILING
   PREPARE   DRAWING    PROPERLY  AND
    ACCURATELY
   PREPARE BAR BENDING SCHEDULE, IF
    NECESSARY
   INDICATE   PROPER   COVER   TO THE
    REINFORCEMENT
   DECIDE      LOCATION     OF    THE
    OPENINGS/HOLEAND SUPPLY ADEQUATE
    DETAILS  FOR    THE  REINFORCEMENT
    AROUND OPENINGS.
   COMMONLY AVAILABLE SIZE OF BARS
    AND SPIRALS SHALL BE USED FOR
    REINFORCEMENT
   FOR A SINGLE STRUCTURAL MEMBER
    THE NO OF DIFF SIZES OF REIN BAR
    SHOULD BE MINIMUM.
   THE GRADE OF REINFORCEMENT BARS
    SHOULD BE CLEARLY MENTIONE DIN THE
    STRUCTURAL DRAWINGS
   WHEN    REINFORCEMENT    IS   LEFT
    EXPOSED FOR FUTURE CONSTRUCTION,
    IT SHOULD BE ADEQUATELY PROTECTED
    FROM CORROSION AND WEATHERING.
   CONGESTION OF THE REIN SHOULD BE
    AVOIDED AT POINTS WHERE MEMBERS
    INTERSECT AND MAKE CERTAIN THAT
    ALL THE REIN SHOWN CAN BE
    PROPERLY PLACED.

   SHOW ENLARGED DETAILS AT THE
    CORNERS,BEAM AND COLUMN JOINT
    AND AT SIMILAR SPECIAL SITUATIONS.
DO NOTS FOR DETAILING
   FLEXURE REINFORCEMENT SHALL NOT BE
    TERMINATED IN A TENSION ZONE.
   LAP SPLICES AHOULD NOT BE USED FOR
    BARS LARGER THAN 36 MM DIA.
   BARS LARGER THAN 36 MM DIA SHOULD NOT
    BE BUNDLED
   DIFERRENT TYPES OF REINFORCING BARS
    SUCH AS DEFORMED BARS AND PLAIN BARS
    AND VARIOUS GRADES SHOULD NOT BE USED
    SIDE BY SIDE AS THIS PRACTICE WOULD
    LEAD TO CONFUSION AT SITE.
DO’S FOR COLUMNS
   A REINFORCED COLUMN SHOULD HAVE
    MIN 4 BARS FOR RECT OR SQ COL AND
    MIN 6 BARS FOR CIRCULAR COLUMNS.
   KEEP   OUTER   DIM  OF   THE  COL
    CONSTANT, AS FAR AS POSSIBLE, FOR
    RE-USE OF FORMS.
   PREFARABLY   AVOID  USE   OF  TWO
    GRADES OF VERTICAL BARS IN THE
    SAME ELEMENT.
DO’S FOR BEAMS AND
SLABS
   WHERE SPLICES ARE PROVIDED IN THE
    REINFORCING   BARS,  THEY    SHOULD BE
    STAGGERED, AND AWAY FROM THE SECTIONS
    OF MAX STRESS.
   WHERE THE DEPTH OF THE BEAM EXCEEDS
    750 MM IN CASE OF BEAMS WITHOUT
    TORSION AND 450 MM WITH TORSION SIDE
    FACE REIN SHALL BE PROVIDED.
   ALL SPACING SHALL BE C/C SPACING OF
    THE BARS.
   DEFLECTION    IN   BEAMS/SLABS    MAY   BE
    REDUCED    BY    PROVIDING    COMPRESSION
    REINFORCEMENT.
   AT BEAM COLUMN INTERSECTION ,ENSURE
    THAT THE MAIN BEAM BARS AVOID THE MAIN
    COLUMN BARS.
   AT BEAM COL INTERSECTIONS , MAIN REIN
    MAY BE SO ARRANGED THAT LAYERS IN
    MUTUALLY PERPENDICULAR BEAMS ARE AT
    DIFF LEVELS.
   TO ACCOMMODATE BOTTOM BARS, IT IS GOOD
    PRACTICE   TO    MAKE   SECONDARY    BEAMS
    SHALLOWER THAN THE MAIN BEAMS ATLEAST
    BY 50 MM.
DUCTILITY
   A DUCTILE MATERIAL IS THE ONE
    THAT   CAN    UNDERGO   LARGE
    STRAINS WHILE RESISTING LOADS

   DUCTILITY IMPLIES THE ABILITY
    TO     SUSTAIN    SIGNIFICANT
    INELASTIC DEFORMATIONS PRIOR
    TO COLLAPSE.
   A BRITTLE MATERIAL OR STRUCTURE
    IS THE ONE THAT FAILS SUDDENLY
    UPON ATTAINING ITS MAXIMUM LOAD.
   MEMBER OR STRUCTURAL DUCTILITY IS
    DEFINED AS THE RATIO OF THE
    ABSOLUTE   DEFORMATION   TO   THE
    CORRESPONDING YIELD DEFORMATION

           =   u    ultimate deformation
                      yield deformation
   THE     SHEAR   REINFORCEMENT
    SHOULD BE ADEQUATE TO ENSURE
    THAT THE STRENGTH IN SHEAR
    EXCEEDS    THE  STRENGTH   IN
    FLEXURE    TO   PREVENT   NON
    DUCTILE SHEAR FAILURE BEFORE
    THE FULLY REVERSIBLE FLEXURE
    STRENGTH OF A MEMBER HAS BEEN
    DEVELOPED.
IS 13920-1993
DUCTILE DETAILING OF RCC STRUCTURES
SUBJECTED TO SEISMIC FORCES

     THIS CODE APPLIES TO ALL RCC
      STRUCTURES WHICH SATISFY ONE
      OF THE FOUR CONDITIONS-
     THE STRUCTURE IS LOCATED –
     IN ZONE   IV OR V
     IN ZONE   III AND I > 1.0
     IN ZONE   III AND INDUSTRIAL STRUCTURE
     IN ZONE   III AND IS MORE THAN 5 STOREY
      HIGH
   BEAMS    AND   COLS   IN    A
    REINFORCED   CONCRETE   FRAME
    SHOULD BE DESIGNED IN SUCH A
    MANNER THAT THE INELATICITY
    IS CONFINED TO BEAMS ONLY AND
    THE    COL   SHOULD    REMAIN
    ELASTIC.
BEAMS
   ATLEAST   TWO   BARS  SHOULD   BE
    PROVIDED CONTINUOSLY BOTH AT TOP
    AND BOTTOM.
   THE POSITIVE MOMENT RESISTANCE AT
    THE FACE OF THE JOINT SHOULD NOT
    BE LESS THAN ONE –HALF OF THE
    NEGATINE     MOMENT    RESISTANCE
    PROVIDED AT THAT FACE OF THE
    JOINT.
   NEITHER THE NEGATIVE NOR THE
    POSITIVE RESISTANCE AT ANY
    SECTION   ALONG  THE   MEMBER
    LENGTH SHOULD BE LESS THAN
    ONE-FOURTH   OF  THE   MOMENT
    RESISTANCE PROVIDED AT THE
    FACE OF THE EITHER JOINT.
   SPACING OF HOOPS OVER A LENGTH OF 2d
    AT EITHER END OF THE BEAM SHALL NOT
    EXCEED-
   d/4
   8 TIMES THE DIA OF THE SMALLEST
    LONGITUDINAL BAR, NEED NOT BE LESS
    THAN 100 MM
   ELSEWHERE,    THE  BEAM  SHALL  HAVE
    VERTICAL   HOOPS  AT  A SPACING  NOT
    EXCEEDING d/2.
                                MIN 2 BARS FOR FULL LENGTH
                                ALONG TOP AND BOTTOM FACE
                                AS > MIN. Bd
                                AS < MAX Bd


         50 m max              50 m max




                                                  d




             db
    2d                                2d
                  HOOP SPACING
                    > d /2
    HOOP SPACING
    < d/4 and 8 db
                             B = BREADTH OF BEAM
                             db = DIAMETER OF LONGITUDINAL BAR

BEAM REINFORCEMENT
COLUMN
   THE SPECIAL CONFINING STAAL WHERE
    REQUIRED MUST BE PROVIDED ABOVE AND
    BELOW THE BEAM CONNECTIONS, IN A
    LENGTH OF THE COLUMN AT EACH END WHICH
    IS LARGEST OF THE FOLLOWING-
   1/6 OF THE CLEAR HEIGHT OF THE COLUMN
   LARGER DIMENSION OF THE COLUMN
   450 MM
   WHEN A COLUMN TERMINATES INTO
    A FOOTING , SPECIAL CONFINING
    REINFORCEMENT SHALL EXTEND
    ATLEAST 300 MM INTO THE
    FOOTING
                         SPECIAL CONFINING
                         REINFORCEMENT
                         > 300 mm




PROVISION OF SPECIAL CONFINING
  REINFORCEMENT IN FOOTINGS
   THE SPACING OF HOOPS USED AS
    SPECIAL              CONFINING
    REINFORCEMENT    SHALL     NOT
    EXCEED –
   ¼ OF THE MIN MEMBER DIMENSION
   NEED NOT BE LESS THAN 75 MM
    NOR MORE THAN 100 MM
   THE PARALLEL LEGS OF THE REC
    HOOPS SHALL BE SPACED NOT
    MORS THAN 300 MM CENTRE TO
    CENTRE.
   IF THE LENGTH OF ANY SIDE
    EXCEEDS 300 MM THEN CROSS TEE
    SHOULD BE PROVIDED OR A PAIR
    OF OVERLAPPING HOOPS MAY BE
    PROVIDED. THE HOOPS SHALL
    ENGAGE PERIPHERAL
    LONGITUDINAL BARS.
         lO


                               JOINT REINFORCEMENT
    lO                         AS PER 8.1


                    > hc / 4


                 TRANSVERSE
                 REINFORCEMENT
                 AS PER 7.2.1         hC

                    > hc / 4
     lO




                    CONFINED JOINT WITH BEAMS
                    FRAMING INTO ALL FOUR SIDES
                    CONFINING REINFORCEMENT AS
                    PER 8.2


COLUMN AND JOINT DETAILING
                           db




                      Ld = DEVELOPMENT
                          LENGTH IN TENSION

                      Db = BAR DIAMETER


FIG. 1:   ANCHORAGE OF BEAM BARS IN
           AN EXTERNAL JOINT.
           LAP SPLICES
   THE LONGITUDINAL BARS SHALL BE
    SPLICED , ONLY IF HOOPS ARE
    PROVIDED OVER THE ENTIRE SPLICE
    LENGTH,AT A SPACING NOT EXCEEDING
    150 MM
   THE LAP LENGTH SHALL NOT BE LESS
    THAN THE BAR DEVELOPMENT LENGTH
    IN TENSION.
   LAP SPLICES SHALL NOT BE PROVIDED-
      WITHIN A DISTANCE OF 2d FROM THE
       JOINT FACE
      WITHIN A JOINT
      WITHIN A QUARTER LENGTH OF THE
       MEMBER WHERE FLEXURAL
       YIELDING MAY GENERALLY OCCUR
       UNDER THE EFFECT OF EARTHQUAKE
       FORCES.
                  Ld




    db                 150 mm
                  Ld = DEVELOPMENT
                       LENGTH IN TENSION

                  Db = BAR DIAMETER

FIG. 2:   LAP, SPLICE IN BEAM

								
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