| With the development of China’s economy and society,urban buildings are constantly being updated and optimized.Therefore,a large number of waste concrete is produced every year,which not only brings severe challenges to construction resources,but also leads to many problems caused by the accumulation of construction waste.In response to the national development policy,the recycling of waste concrete will be the mainstream trend of future development.In this paper,the recycled aggregate obtained by crushing construction waste is made into recycled concrete,and on this basis,the research on recycled concrete and its structural components is carried out as follows:1.In order to analyze the optimal range of recycled coarse and fine aggregate and waterbinder ratio,seven groups of recycled concrete ratio were formulated,and the compressive tests were carried out on the test blocks successively.When the strength of the sample is the maximum,the optimal ratio of water to binder is 0.4,and the replacement rate of recycled coarse and fine aggregate is 50% and 30%,respectively.2.Design the block type of the new recycled concrete self-insulation block,and simulate the compressive test of the block through ABAQUS.It is concluded that the hollow ratio,the number of holes and the arrangement of holes all have influence on the strength of the hollow block,and the lower the hollow ratio,the more uniform and symmetrical the arrangement of holes,the higher the strength of the hollow block.The strength of type C1 block is the highest,which is 14.21 MPa,and all the blocks meet the load-bearing requirements.3.Based on the powerful nonlinear analysis ability of ABAQUS software,a simplified separated model of masonry components was established to simulate the compressive test and shear test of masonry.In the finite element model,the traction-separation model was used to simulate the contact properties of the block-mortar interface,and the CDP model and the recycled concrete block constitutive model were used to define the material properties of the blocks.Input the values of each parameter into the model,and verify the reliability of the model by simulating the operation mechanism of normal contact criterion and tangential contact criterion.4.According to the calculation results of masonry simulation test,the influence of grooving and block strength on masonry strength is analyzed.The influence of grooving on masonry strength is very small and can be ignored.The higher the block strength,the higher the ultimate bearing capacity of the masonry.Through the analysis of the simulation results and the formula model given in the code,the calculation formula of the ultimate bearing capacity of masonry is finally fitted.5.Establish an integral model of recycled concrete block wall,simulate the pseudo-static test of the wall,and analyze the influencing factors of the seismic performance of the masonry wall through the test results.From the simulation data,it can be seen that the initial stiffness,failure load and displacement of the masonry wall are negatively related to the aspect ratio,and the ductility performance does not change with the aspect ratio;when the vertical pressure increases,the ultimate load of the masonry wall first It becomes smaller after becoming larger,but the change of vertical load has little effect on the initial stiffness of the masonry wall. |
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