Experimental Study On Basic Mechanical Properties And Durability Of The Desert Sand Concrete With Lithium Slag And Polypropylene Fiber

Desert sand concrete is a new type of environment-friendly concrete,the desert sand by a certain percentage instead of ordinary sand,equipped with concrete requirements in line with the actual requirements of the concrete.Desert sand concrete basic mechanical properties and durability and general concrete is very similar,but because of its easy to shrink shrinkage,impermeability and other issues have not been widely used,in order to improve the performance of desert sand concrete above,the above problems are solved by incorporating mineral admixtures of lithium slag and low elastic modulus fibers.The above problems are solved by incorporating mineral admixtures of lithium slag and low elastic modulus fibers.Lithium slag is a large-scale industrial solid waste discharged from the lithium salt production process,which effectively improves the strength of concrete and improves the durability of concrete impermeability and frost resistance,and polypropylene fiber can greatly enhance the internal structure of concrete,the tensile strength of concrete has significantly improved utility.Xinjiang,the rational development of desert sand for engineering construction,reduce project cost,contain desertification and dust storms,to contribute to the ecological environment,from the perspective of long-term development,has far-reaching economic and social benefits.In this paper,the desert sand sand in Xinjiang is replaced by a certain proportion of ordinary sand sand concrete,and the industrial waste lithium slag and polypropylene fiber are used to modify the desert sand concrete,the basic mechanical properties and durability of lithium slag polypropylene fiber reinforced concrete under different desert sand replacement rates are discussed in depth.The basic mechanical properties,frost resistance and impermeability of the concrete,such as cube resistance,splitting tensile,axial compression,compressive stress-strain curve,were analyzed.The experimental results show that when the replacement rate of desert sand is 30%,the mechanical and durability of the specimen is the best,and the peak strain and axial compressive strength are expressed as follows:?c=(80.02?fc-3737.86)x106,the influence coefficient of desert sand substitution rate is obtained.When the sandy sand,polypropylene fiber and lithium slag were incorporated,the compressive strength of the cube increased by 17.56%,the axial compressive strength increased by 20.06%,the splitting tensile strength increased by 53.26%,and the mass loss rate after freezing and thawing The weight loss rate decreased by 34.78%,the dynamic modulus of elasticity decreased by 25.5%,and the average seepage height decreased by 22.28% after pressurized water infiltration.Considering the overall trend of concrete quality,strength and modulus of elasticity and the average seepage degree in the impermeability of concrete,the factors in the test were sorted by polypropylene fiber> lithium slag> desert sand.