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.