Experimental Study On The Axial Compression Performance Of C50 Recycled Coarse Aggregate Self-compacting Concrete Short Columns

With the acceleration of my country’s urbanization process,the output of solid construction waste is also increasing.Building solid waste not only pollutes the environment,but also a waste of resources.In recent years,my country has proposed that"urban planning must adhere to the concept of green and sustainable development."How to deal with solid waste in construction while adhering to the concept of green is also a major challenge now.With the increasing complexity and scale of concrete engineering and the increasing requirements for high-performance concrete,the application of solid construction waste as a coarse aggregate for configuring high-strength self-compacting concrete will be of great research significance.This paper intends to use recycled coarse aggregate to configure C50 recycled coarse aggregate self-compacting concrete,and select orthogonal table L9(4~3)for orthogonal test design to explore the water-binder ratio,recycled coarse aggregate content,fly ash replacement rate,Under the influence of four influencing factors of admixture content,the influence degree and change law of each factor on the mechanical properties and working performance of C50 recycled coarse aggregate self-compacting concrete,find the best level combination of four factors,Determine the optimal mix ratio of C50 recycled coarse aggregate self-compacting concrete,and fabricate reinforced concrete short columns,and analyze the working performance and mechanical properties of C50 recycled coarse aggregate self-compacting concrete short columns through axial compression tests.The main conclusions are as follows:(1)Analyze the results of the orthogonal test by the range method and the factor level method,and finally get the optimal mix ratio of C50 recycled coarse aggregate self-compacting concrete that meets the mechanical properties and working performance:A3B1C2D3,which is the water-binder ratio 0.274,the replacement rate of recycled aggregate is 30%,the replacement rate of fly ash is 30%,and the admixture content is 0.52%.(2)Using the optimal mix ratio,make short columns of C50 Recycle Coarse Aggregates Self-Compacting Concrete(RCASCC)and C50 Self-Compacting Concrete(SCC),The study found that the bearing capacity of C50-SCC short column and C50-RCASCC short column did not change significantly.According to the calculation formula of normal section bearing capacity,The calculation formula can be used for the calculation of C50-SCC short column and C50-RCASCC short column.(3)The working performance and mechanical properties of the two types o f concrete short columns are small,and their failure modes,load-displacement curves,etc.are similar,indicating that when recycled coarse aggregates partially replace natural coarse aggregates,Will not affect the mechanical properties and working conditions of the components.