基于拔出法的超高强混凝土强度检测试验

为了验证拔出法在超高强混凝土强度检测上的适用性,采用先装拔出法及后装拔出法对超高强度混凝土进行强度检测试验。试验用超高强混凝土分C120、C150、C180共3个强度等级,每个等级设置6组试件及相应数量的立方体试块。利用最小二乘法对试验数据进行拟合,并计算回归方程的各类参数,结果表明,各类参数都在合理的范围内,因此得出拔出法适用于检测超高强混凝土强度的结论。通过对比,得出同种材料下先装拔出法精确度更高、超高强混凝土的测强曲线与钢纤维砂浆趋势相近、后装拔出法的检测范围较先装拔出法更广的结论。

Strength testing of ultra-high strength concrete using pull-out method

To verify the applicability of the pull-out method in strength testing of ultra-high strength concrete, the cast-in-place pull-out method and post-install pull-out method were used to test the strength of ultra-high strength concrete. The strength of test pieces was graded at threelevels, C120, C150, and C180, and six groups of test pieces and a certain number of test cubes were selected for each strength level. Through experimental data fitting with the least square method and calculation of various parameters of the regression equation, some conclusions are drawn: all kinds of parameters are within reasonable ranges, and the pull-out method is suitable for testing the strength of ultra-high strength concrete. Comparison of data from different pull-out methods shows that, for the same kind of material, the cast-in-place pull-out method has higher accuracy, the strength curve of ultra-high strength concrete has a similar trend to that of steel fiber cement mortar, and the strength detection range of the post-install pull-out test is wider than that of the cast-in-place pull-out test.