Pervious Cement Concrete Aggregate-Slurry Bonding Performance And Numerical Simulation

In recent years,pervious concrete research mostly focused on the macro aspects,including the pervious concrete mechanics performance and waterproof performance,people who study on aggregate bond performance is relatively scarce,this paper consider the thickness of cement slurry layer wrapped on the aggregate surface,the roughness of the aggregate surface,the aggregate type,the experiments on the bonding properties of aggregates are carried out,and he mechanical properties of permeable concrete are simulated numerically,The main research are as follows:(1)Granite and basalt were processed into general cylindrical,and use the diamond grinding of the bonding surface,and then stone will be bonded together by slurry,using the plastic gasket control the thickness of the slurry,direct tensile test is performed,test results show that the cement slurry in the 1.0-1.4 mm thickness range,with the increase of thickness of cement specimen tensile strength is increased,it can be proved that within the range of 0.5-0.7mm slurry thickness,the bond strength between pervious concrete aggregate also increases with the increase of thickness.(2)Based on indoor direct tensile test curve,select a set of initial mesoscopic parameters,change one of the parameters and the other parameters are fixed,analyzed the influence of the change of parameters for the simulation results,the trial and error method is adopted to try and adjust,and finally select a set of appropriate discrete element mesoscopic parameters,and these parameters to simulate permeable concrete compression test under different thickness of the wrapped slurry,using software to generate particles and wall,gives model bond properties and microstructure parameters,loading conditions simulated permeable concrete block was damaged,the process of the contrast of the pervious concrete discrete element model and the actual failure pattern of block,and test curve,it is found that their failure forms are similar,and the compressive strength is in the same level,which verifies the rationality of the calibrated mesoscopic parameters,it can be used as a reference for the study on the microscopic stress of permeable concrete and the calibration of discrete element parameters.