Experimental Study On Axial Compressive Properties Of Seawater And Sea Sand Recycled Concrete

In recent years,with the development of China,construction waste generated in engineering construction has gradually become a problem to be solved.At present,China is vigorously developing the recycling of construction waste,and the recycled aggregate produced is put into engineering construction again.Not only can it save resources,but also alleviate a series of environmental and social problems caused by construction waste stacking,but the recycling of construction waste polluted by seawater generated during the construction of coastal areas has become an urgent problem to be solved.The use of seawater,sea sand and recycled coarse aggregate as construction materials can not only solve the problem of recycling construction waste in coastal areas,but also play an active role in the construction of islands,ocean development and other freshwater and river sand-deficient areas in China.With the gradual promotion and utilization of FRP materials,the use of highly corrosion-resistant GFRP bars to replace steel bars in the future can just ignore the corrosive effects of harmful substances such as chloride ions in seawater and sea sand on structures.Under the above background,this research project will study the mechanical properties of seawater and sea sand recycled concrete to provide a theoretical reference for future FRP structure research.At present,there are few related researches on seawater and sea sand recycled concrete.In order to perfect the research in this field,the research topic of this master thesis takes seawater and sea sand recycled concrete as the research object,making 162 cylinders and 108 cubes,and adding The control specimens without seawater and sea sand were used to study the effect of recycled aggregate replacement rate,mix ratio and age on the axial compression performance of seawater sea sand recycled concrete.(1)Analyze the difference in physical properties of different coarse and fine aggregates,and compare the influence of different parameters on the performance of seawater and sea sand recycled concrete;(2)Perform axial compression test on all test pieces,analyze the replacement rate of recycled aggregates(0%,50%,100%),mix ratio(C30,C40,C50)and age(28 days,90 days and 180 days))The influence of parameters on the axial compression failure form,stress-strain curve,compressive strength,elastic modulus and Poisson's ratio of recycled concrete in seawater and sea sand;(3)The stress-strain curve of seawater and sea sand recycled concrete is dimensionless,and the stress-strain curve of seawater and sea sand recycled concrete after dimensionless is fitted with reference to the Guo Zhenhai constitutive equation,and its constitutive equation is proposed To provide a theoretical reference for future material research.