新型结构加固用灌浆料回弹测强曲线制定试验研究

Experimental study on establishment of rebound strength curve for a new type of structural reinforcement grouting material

采用新型结构加固用灌浆料制作了边长为150 mm的立方体试块,分别采用HT225-A普通回弹仪和HT450-A高强回弹仪进行了回弹试验,并对试块进行了抗压强度试验。对新型结构加固用灌浆料是否适用《回弹法检测水泥基灌浆材料抗压强度技术规程》(T/CECS 801—2021)的测强曲线进行了验证。试验结果表明:新型结构加固用灌浆料不适用于《回弹法检测水泥基灌浆材料抗压强度技术规程》(T/CECS 801—2021)的测强曲线。基于最小二乘法原理,分别采用幂函数、线性函数、指数函数、抛物线函数的表达式,对新型结构加固用灌浆料普通回弹和高强回弹的试验数据进行了回归分析,对比了回归公式的相关性系数、强度平均相对误差和强度相对标准差,确定了精度较高的测强曲线。

Cubic test blocks with a side length of 150 mm were made for rebound testing by using HT225-A ordinary rebound instrument and HT450-A high-strength rebound instrument,and then the compressive strength of the test blocks were tested.It was verified whether the new type of structural reinforcement grouting material was suitable for the strength testing curve of Technical specification for inspecting of cementitious grout compressive strength by rebound method(T/CECS 801—2021).The test results indicate that the new type of structural reinforcement grouting material is not suitable for the strength testing curve of Technical specification for inspecting of cementitious grout compressive strength by rebound method(T/CECS 801—2021).Based on the principle of least squares method,regression analysis was conducted on the experimental data of the new type of structural reinforcement grouting material of ordinary rebound and high-strength rebound by using expressions of power function,linear function,exponential function,and parabolic function.Then the correlation coefficient,average relative error of strength,and relative standard deviation of strength of the regression formula were compared to determine the strength testing curve with higher accuracy.