Experimental Study On The Effect Of Brick Content On The Basic Properties Of Recycled Concrete

Waste concrete and waste bricks account for a large proportion of construction waste.According to incomplete statistics,the proportion of waste concrete is about 40%,and that of waste brick is about 30%.At present,most of the construction waste disposal in our country still adopts the direct open-air landfill,which not only occupies the land,but also pollutes the environment.If the construction industry can recycle the waste concrete and the waste brick,which not only can meet some of the needs of the project,but also solve the problem of construction waste disposal.In addition,the recycling of construction waste is in line with the idea of developing circular economy and sustainable development strategy in China.Up to now,most of the research has focused on waste concrete coarse aggregate or abandoned brick coarse aggregate partially or completely instead of natural coarse aggregate for experimental study.While,in this experiment,the coarse aggregate is all recycled,and the coarse aggregate of waste brick is used to replace the coarse aggregate of waste concrete.That is,recycled coarse aggregate is made from the concrete beam specimen discarded in the laboratory and the waste brick sorted from the construction waste.Based on these recycled coarse aggregate,plus cement,natural sand,water,and water reducing agent is,which could produce recycled coarse aggregate concrete containing brick.In this paper,the performance indexes of coarse aggregate of waste concrete and waste brick are tested firstly.Secondly,The cubic compressive strength of the standard recycled concrete with 100% of waste concrete instead of natural coarse aggregate is31.76 MPa in 28 d.Then,the content of brick particles in recycled concrete is changed to make the recycled concrete containing brick particles.The slump and expansion of recycled concrete containing brick particles were tested for soil specimens and members and before the specimens were formed.Thirdly,through cube,prism compressive strength test,free vibration attenuation method and ultrasonic testing method,the mechanical properties,damping properties and damage properties of recycled concrete containing brick are studied.The effect of brick particle content on the basic properties of recycled coarse aggregate concrete is presented.The results show that the compressive strength and working performance of recycled concrete can be decreasedby adding brick particles,but the damping property of recycled concrete members will be improved by adding brick particles.So we can find a critical brick replacement rate that improves the damping performance of the component while ensuring its strength and performance.The critical brick replacement ratio is 10 and the compressive strength and damping performance of recycled concrete are better.