基于四点弯曲试验分析HPFRCC抗拉特性研究

RESEARCHES ON TENSILE PROPERTIES OF HPFRCC BASED ON ANALYSIS OF FOUR-POINT BENDING TEST

单轴抗拉试验(UTT)是目前国际上公认的最能展现HPFRCC抗拉特性的试验方法,但UTT试验操作复杂且对试验要求高,不便于实际工程中的质量控制。本文根据四点弯曲试验的实测荷载-跨中挠度曲线,并结合截面平衡条件及应力与应变分布,建立了采用四点弯曲试验分析HPFRCC抗拉特性的计算方法。计算结果与实测结果的对比表明,该模型能较好地评价HPFRCC的抗拉特性,为今后HPFRCC在实际工程中的大量应用提供了一种间接测定其受拉强度和极限拉应变的分析方法。

Uniaxial Tensile Test （UTT） is internationally recognized as the most comprehensive test method which can display the tensile properties of HPFRCC, but the operation of UTT test is so complicated that it is incon- venient to take quality control in practice. According to the measured load-deflection curve of four-point bending test, section equilibrium conditions and stress and strain distribution, the calculating method on tensile properties of HPFRCC was established by evaluating four-point bending test results. The model assumes that the stress distribution of HPFRCC in compressive zone is linear and stress distribution in tensile zone is bilinear, which is in accordance with the performance of HPFRCC and is simple for calculating. Comparisons between the calculated and measured results indicate that proposed model is able to evaluate the tensile properties of HPFRCC, which provides an indirect analysis method on the tensile strength and ultimate tensile strain of HPFRCC for practical application.