Development And Application Of Recycled Aggregate Concrete Rootstone From Construction Waste

Due to years of sedimentation,the river channel in the lower reaches of the Yellow River is continuously rising,and the flood pressure on the dam slopes on both sides of the river is increasing.Therefore,it is necessary to continuously strengthen the river dam to ensure the safety of the lower Yellow River.The use of slope protection stone is one of the important means to improve the safety of the dam shore.However,the government's restrictions on the exploitation of stone resources have led to an increase in the price of stone,and as the cost of labor for technical workers has increased,the cost of slope protection stone has increased significantly.Moreover,many engineering projects often cause delays or even stoppages due to insufficient materials.While the space for human development is expanding,a large amount of construction waste has been generated.In order to solve the above problems,the combination of laboratory test and theoretical simulation analysis is carried out to study the mechanical properties,durability and impact resistance of construction waste recycled aggregate concrete slope protection stone.The aim is to obtain a suitable replacement ratio of recycled aggregates.Therefore,the problem of lack of natural root stone and reuse of construction waste can be solved to some extent.The conclusions are as follows:(1)Basic characteristics of recycled aggregates.It can be seen from the test that the grade of recycled aggregate meets the requirements of the specification,but its water absorption rate is much larger than that of natural aggregate.For this reason.when performing the mixture ratio test,a certain proportion of free water is added according to the water absorption of different materials to ensure the workability of the concrete.(2)Analysis of mechanical properties of recycled aggregate concrete.Through the compression and flexural tests,the performance of recycled aggregate concrete is slightly inferior to that of ordinary concrete,but it still meets the performance requirements of the project.And when the replacement rate is less than 50%,the mechanical properties of concrete are less affected.In the case of the same replacement rate,the order of strength from high to low is single-mixed fine aggregate,double-mixed,single-mixed coarse aggregate.(3)Durability analysis of recycled aggregate concrete.It can be seen from the freeze-thaw test and the anti-carbonization test that although the recycled aggregate will reduce the durability of the concrete,the impact is small,and the recycled aggregate concrete still meets the engineering requirements.Under the premise of meeting the engineering requirements,the optimal mix ratio of concrete is 50%recycled fine aggregate concrete,and the best benefit ratio of concrete is 100%recycled fine aggregate.(4)The shape design of the recycled aggregate concrete root stone.Through the diferent methods of root stone size calculation,considering the impact resistance and anti-lost ability of the root stone,the shape of the root stone that meets the engineering requirements is designed.(5)Analysis of impact resistance of recycled aggregate concrete roots.The ANSYS finite element software was used to compare and analyze the impact resistance of new root stones and traditional root stones,and the advantages of new root stones were determined.The anti-loss performance of the root stone was simulated and analyzed.