INCORPORATED CHANGES IN SECTION 3 AND 4 ON THE DESIGN REQUIREMENTS APPROVED BY THE CIVIL ENGINEERING DEPARTMENT.

Changes incorporated in Section 3 on general design requirements are as follows:-- (1) Recommendations regarding prototype testing have been added .(2) Recommendations regarding stability of the structure as a whole have been given in addition to the one regarding the stability of the overhanging members .(3) Recommendations regarding frame analysis such as substitute frames have been given.(4) Rules for effective width of flange for T and L beams have been given.(5) Recommendations regarding slender beams have been changed.(6) Minimum eccentricity for the design of compression members has been specified.(7) Rules governing the use of bundled bars have been added .(8) Curtailment rules for reinforcement in beams and slabs have been given.(9) Recommendations regarding critical sections for shear and minimum web reinforcement have been added (10) Recommendations regarding minimum tensile reinforcement in beams have been modified.(11) Recommendations regarding side face reinforcement in beams have been added. (12) The clause on span to depth ratio for controlling deflection has been modified and elaborated to take into account the type and percentage of reinforcement provided Short term and long term deflection has been added. (13) Detailing rules required for crack control have been given in the code .(14) Guidance on the determination of effective length of columns in framed structures has been added. SECTION 4 INCLUDES SPECIAL DESIGN REQUIREMENTS:-- Flate slabs , deep beams have been added by superseding the rules of section 3 ,as applicable and recommendation for design of of deep beams have been added (2) Guidance for the design of ribbed and voided slabs has been included (3) The clauses on design of flate slabs have been revised .Shear in flate slabs and openings in the flate slabs are now covered with the details.(4) The clause on footings have also undergone some changes regarding design for shear and transfer of load at the base of the column.

SIGNIFICANT CHANGES INCORPORATED IN SECTION 2 MODIFIED IN APPENDIX B OF IS:456-1964 AS PER THE DESIGN AND SCOPE COVERED IN THE RESPECTIVE CODE AND STANDARD GIVEN IN IS:456-1978.

The following changes are incorporated in Section 2 of the clauses of IS Code ie due to more type of cement are now permitted , pozzolanas , light weight aggregates and cold twisted deformed bars of Grade Fe 500 .(2) Regarding durability, guidance concerning minimum cement content and maximum water cement ratio for different envoirnmental conditions, including types of cement to be used for resisting sulphate attack as per the limitations given in an appendix (3) Informations regarding properties of the concrete such as modulus of elasticity, tensile strength, shrinkage,creep and co efficient of the thermal expansion (4) Recommendations regarding construction tolerance relating to form work and placing of steel (5) Recommendations regarding acceptance criteria for the hardened concrete represented by the core tests (6) Clauses on the load testing of structure have been accordingly modified.This ,in fact is a rationalisation of the ultimate load method which was briefly covered in IS :456-1964 .The working stress method as practiced earlier has been retained with the design for shear and torsion being aligned with the corresponding provisions for limit state method of design . Method of design for shear and torsion has been completely revised, incorporating the results of the latest research on the subject matter deliberation required to be verified by the study made by the council of civil engineering department. The concept of the development length for reinforcement has been introduced and the required significant changes incorporated in Section 2 as mentioned above.