Study On The Effect Of Admixture On Mechanical Properties Of LC30 Prefabricated Ceramsite Concrete

In this paper,the LC30 prefabricated lightweight aggregate concrete made from mixed sand,active mineral admixture and super plasticizer,which is a mixture of light coarse aggregate ceramsite,mixed sand,has light weight,high strength and heat insulation preservation in accordance with the specification of lightweight aggregate concrete technical specification(JGJ 51-2002).It is a kind of green concrete which saves resources and saves energy.The main contents and achievements of LC30 prefabricated lightweight aggregate ceramsite concrete are as follows:First,the properties of LC30 lightweight aggregate concrete,such as ceramsite,cement,mineral admixture,fine aggregate and super plasticizer,were tested in accordance with the corresponding national standards.Second,the preliminary mixture ratio calculation was carried out according to the specifications,and the trial mixing test was carried out.On this basis,the orthogonal test method was used to test the volume of cement(380kg/m~3?420kg/m~3?460kg/m~3),sand rate(33%?35%?37%),the amount of water(160kg/m~3?180kg/m~3?200kg/m~3)and the total volume of coarse aggregate(1.20m~3?1.30m~3?1.40m~3)in four different levels,with the apparent density and the compressive strength of different ages(3d,7d,28d).As the evaluation index,the influence of each factor on the apparent density and the compressive strength is analyzed by the difference and variance,and the mixture ratio is adjusted according to the influence degree of each factor,and the ratio of the laboratory is obtained.The cement substitution rate of mineral admixture is 10%,15%and 20%respectively on the base mix ratio of the laboratory,and the compressive strength,flexural tensile strength,splitting tensile strength,compressive elastic modulus and impact resistance of different mineral admixtures and mineral admixtures are studied when the content of mineral admixtures is changed.The law of the influence of performance and density.The microscopic properties of ceramsite and lightweight aggregate concrete were analyzed by SEM.The cube compressive strength is the basis for determining the grade of lightweight aggregate ceramsite concrete.In the study of the changing law of mechanical properties and density,the LC30 lightweight aggregate ceramsite concrete in this paper meets the requirements of compressive strength.The regression curves and equations of the other three other mechanical properties and compressive strength are proposed by the experiment,and four of them have been obtained.The relationship between mechanical properties.The experimental results in this paper provide technical data for the engineering application of lightweight aggregate ceramsite concrete.