透水混凝土压缩试验及劈裂试验三维离散元分析

Three-dimensional Discrete Element Analysis of Pervious Concrete Compression Test and Splitting Test

为研究透水混凝土细观力学参数与宏观力学性能的关系,通过PFC3D三维颗粒流建立平行粘结模型,对所建立方体透水混凝土进行单轴压缩试验模拟,得到砂浆粘结力提高倍数低于2.0时,两者呈y=x趋势增长,高于2.0时,呈y=1.54 ln(x)+0.90非线性趋势增长;三轴压缩试验模拟,得到围压从5 MPa~20 MPa,透水混凝土抗压强度提高了约2~3倍,表明结构可显著增强透水混凝土力学性能,并计算得透水混凝土的c、φ值分别为0.8 MPa、24°;压条劈裂试验模拟结果得透水混凝土劈裂抗拉强度为2.43 MPa,与试验结果相差0.08 MPa,提供了一种较为可靠的劈裂试验替代方法。

In order to study the relationship between meso mechanical parameters and macro mechanical properties of pervious concrete,a parallel bond model was established by PFC3D particle flow,and uniaxial compression test was carried out on the constructed cubic pervious concrete.It was found that when the increase ratio of mortar bond strength was lower than 2.0,the two showed a y=x trend,and when the increase ratio was higher than 2.0,the two showed a y=x trend.The nonlinear trend is y=1.54 ln(x)+0.90.The results of triaxial compression test show that the confining pressure ranges from 5 MPa to 20 MPa,and the compressive strength of pervious concrete is increased by about 2 to 3 times,indicating that the structure can significantly enhance the mechanical properties of pervious concrete,and the calculated values of c and of pervious concrete are 0.8 MPa and 240 respectively.The result of the splice test shows that the tensile strength of pervious concrete is 2.43 MPa,which is 0.08MPa different from the test result.It provides a reliable alternative method for the spliting test.