Research On Compression Property Of Recycled Aggregate Concrete Under The Coupling Effect Of Compressive Stress And Sulfate Erosion

The process of concrete’s sulfate erosion is a complex phenomenon involving the effects of physics,chemistry and mechanics.Piers,underground infrastructure s,hydraulic buildings,and the dam are the most vulnerable parts of the concrete’s sulfate chemical erosion,under their own weight of the structure and some of the vehicles and pedestrians load,also receiving the sulfate erosion in the water.At present our country is in the period of building the construction.In order to effectively reduce the damage of environmental pollution,reduce the amount of waste c oncrete,achieve the sustainable coordinated development,some technology and research related to the recycled aggregate concrete has developed rapidly.To study the durability of regenerative concrete and propose improvement measures will improve the life of recycled aggregate concrete and improve the safety and practicability of the structure.However,in the existing researches,the research on the properties of recycled aggregate concrete under multiple factors is less,which results in a lack of regula rity and general controversy.In this paper,the mechanical properties and durability of the recycled aggregate concrete under the joint action of compressive stress and sulfate erosion are studied.The main content is as follows:1.According to the replace rate of recycled aggregates,sulfate solution concentration,stress levels,dry-wet cycles,design experiment,prepare 99 prism specimens and do the compressive stress and sulphate erosion’s test under separate function and the function of the coupling.2.Each specimen is compared,measure its quality loss rate and relative dynamic elastic modulus and study how replace rate of recycled aggregates,sulfate solution concentration,stress levels,dry-wet cycles affect the performance of recycled concrete durability.3.Do the monotonic compression load test for each specimen to observe the failure pattern of the specimens,obtain each stress-strain full curves of the specimens,and study the peak stress,peak strain,ultimate strain,modulus of elasticity.A polynomial fitting method is adopted to give the whole curve ’s expression of the rising and descending segment,and the monotone load model of the single axial compression after the sulfate erosion of the regenerated concrete is established.The effects of regeneration aggregate substitution rate,sulfate solution concentration,stress level and wet cycle on mechanical properties of recycled concrete were studied.