Study On Mechanical Properties Of Recycled Concrete With Recycled Fiber Based On Meso-Scale Numerical Simulation

As our country pays more attention to the environment,more scholars pay attention to the treatment of solid waste in construction and the recycling of resources.At present,recycled concrete has been applied to actual projects.Many scholars at home and abroad have paid attention to the performance of recycled concrete.This thesis analyzes the structure of waste fiber recycled concrete at the customary level,and divides it into new hardened cement mortar,old hardened cement mortar,new interface,old interface,natural aggregate,recycled aggregate,and waste fiber.Complex structure.First,the fuller gradation curve is used to calculate the number of aggregates in the model,and the coordinates of the aggregates,the particle size and the center point coordinates of the waste fiber are randomly generated by the Monte Carlo method.Finally,python language and abaqus finite element software are used to realize the mesoscopic model of waste fiber recycled concrete,calculate the uniformity coefficient of aggregate and waste fiber,and perform numerical simulation of axial tensile and compressive tests on it.The effects of the tensile and compressive failure form of waste fiber recycled concrete and the uniformity coefficient of waste fiber on the tensile strength and compressive strength are analyzed.The specific research results are as follows:(1)Through tensile numerical simulation,it can be concluded that under the same recycled aggregate replacement rate,when the aggregate uniformity distribution coefficient is too high,the tensile strength of recycled concrete will be weakened;under the same aggregate uniformity distribution coefficient,The tensile strength of recycled concrete will decrease as the replacement rate of recycled aggregate increases;when the replacement rate of recycled aggregate is 50%,waste fiber recycled concrete will first increase with the increase in the volume of waste fiber When the replacement rate of recycled aggregate is 50% and the amount of waste fiber blended is 0.12,the tensile strength value of waste fiber recycled concrete is higher;when the replacement rate of recycled aggregate is 50%,the amount of waste fiber blended When it is 0.12,the tensile strength and peak strain of waste fiber recycled concrete will decrease with the increase of the uniformity distribution coefficient of waste fiber,and the reduction effect of shear peak strain is relatively obvious;compare the numerical simulation results with other documents The test phenomenon and the simulation are consistent,verifying the applicability of the simulation(2)The conclusion is drawn from the compressive value: under the same recycled aggregate replacement rate,when the aggregate uniformity distribution coefficient is too high,its compressive strength will be weakened;under the same aggregate uniformity distribution coefficient,the recycled concrete The compressive strength will decrease as the replacement rate of recycled aggregates increases;when the replacement rate of recycled aggregates is 50%,waste fiber recycled concrete will first increase and then decrease as the volume of waste fibers increases.When the replacement rate of recycled aggregate is 50% and the amount of waste fiber blended is 0.12,the compressive strength value of waste fiber recycled concrete is higher;when the replacement rate of recycled aggregate is 50% and the amount of waste fiber blended is 0.12,The compressive strength of waste fiber recycled concrete will decrease with the increase of the uniformity distribution coefficient of waste fiber.Compared with the test,the test result is consistent with the simulation trend,which verifies the correctness and applicability of the simulation.