Bond strength of reinforcement in high-strength concrete

Abstract

The use of high-strength concrete is becoming popular around the world. The american code, ACI 318-95 is used in many countries to calculate the development length of deformed bars in tension. However, current design provisions of ACI 318-95 are based on empirical relationships developed from tests on normal strength concrete. The results of a series of tests on high-strength concrete, reported in the literature, from six research studies are used to review the existing recommendations in ACI 318-95 for design of splices and anchorage of reinforcement. It is shown that ACI 318-95 equations may be unconservative for some cases beyond 62 MPa (9 ksi).