Empirical equations for prediction of split tensile and flexural strength of high strength concrete including effect of steel fiber

The current Indian Standard IS: 456-2000 has the equation for prediction of flexural strength which is valid only up to concrete strength of 55 MPa and with introduction of High Strength Concrete (HSC) in the standard, there is need to develop equation and relationship which can predict flexural and split tensile strength of HSC including the effect of steel fibres. This study is aimed to develop relationship between the ratios of split tensile to flexural strength which is applicable to concrete having strength range from 15 MPa to 150 MPa. The study is done by analyzing experimentally obtained test results of a total 120 specimens for flexural strength and 120 specimens for split tensile strength. Further study is also conducted on steel fibre reinforced concrete samples by analyzing experimentally obtained test results of a total 24 specimens for flexural strength and 30 specimens for split tensile strength. The results obtained from the test are compared with empirical equations given by International standards and literatures. On the basis of analysis of results, ratio of split tensile strength to flexural strength is recommended for concrete with and without steel fibre having wide strength range from 100 to 120 MPa. Empirical equations for prediction of spilt tensile and flexure strength of normal to high strength concrete is proposed and applicability of proposed equation for evaluation for normal to high strength steel fiber reinforced concrete is also discussed.