混凝土轴心受拉全曲线试验的新方法

A New Test Method of Full Stress-strain Curve of Concrete in Axial Tension

混凝土轴拉应力-应变全曲线反映了混凝土强度、变形等诸多特性,在总结和分析了不同拉伸应力-应变全曲线试验方法的基础上,基于细观损伤模型的损伤本构关系模型,提出了在混凝土轴心受压试验的同时通过测定混凝土横向拉伸变形,利用优化算法识别得到混凝土拉伸损伤参数和材料常数,进而得到混凝土单轴抗拉强度和应力-应变全曲线,并用已有试验结果加以验证。结果表明,理论预测结果与试验结果吻合良好。

The tensile stress-strain curve of concrete reflects many performances such as strength and deformation. The existed test methods obtaining softening response of concrete in tension were summarized and discussed. Based on the damage constitutive relation established by the author, a new test method of strength and deformation of concrete under axial tension was suggested. Through the specimen subjected axial compressive loading, transverse tensile strain was measured and random field parameters were identified by optimization algorithm. The full tensile stress-strain curve of concrete was also determined. Compared with test results, it is found that the analytical results have a good agreement with experiments.