STUDY ON CORRESPONDING RELATIONSHIPS BETWEEN FLEXURAL LOAD-DEFORMATION HARDENING CURVES AND TENSILE STRESS-STRAIN HARDENING CURVES OF UHTCC

Uniaxial tensile test is an effective method for investigating the mechanical performance of UHTCC (short for Ultra High Toughness Cementitious Composite). However, its application is limited due to difficulties in performing such a test. In this paper, the flexural properties and uniaxial tensile properties are studied by four-point bending test and uniaxial tensile test respectively. Comparisons are made between flexural load-deformation hardening curves and tensile stress-strain hardening curves, as well as basic mechanical indexes, toughness indexes, ductility indexes and multiple cracking patterns. The test results show that the strain hardening performance, multiple cracking, ultimate high ductility and toughness can be reflected by four-point bending test. An ultimate tensile strain formula is proposed based on theory analysis and test results. The predicted values calculated by the formula agree well with the test results; hence the validity of the formula is verified. The four-point bending test method is a simple and practical method, which can substitute for the uniaxial tensile test method to estimate the special mechanical performance of UHTCC.