Study On The Influencing Factors Of Performance Of High-Strength Pumping Light-weight Aggregate Concrete

High-strength lightweight aggregate concrete,with light weight,high strength,thermal insulation,sound insulation,seismic,environmental protection,and many other excellent properties,make its in high-rise buildings,high-rise building and bridge construction has great technical and economic advantages and social benefits.Light aggregate concrete is a kind of sustainable development of green building material,for the research of high-strength pumping light aggregate concrete,to promote light aggregate concrete is widely used in structural engineering has great social and economic benefits.This paper adopts the chongqing as a building material co.,LTD.,the production of high-strength shale ceramsite,strength of the cylinder pressure is 8.2 MPa,through adaptation phase mixture ratio design,formulate the 28 d strength grade of concrete LC40,mixture slump of 220 mm,have good working performance,and dry apparent density of 1927.5 kg/m3 of high-strength lightweight aggregate concrete pumping.In this paper,the slump loss mechanism of pump-feed concrete is discussed in this paper,and a solution is proposed for the floating phenomenon of light aggregate in the experiment.According to the ratio of the benchmark,the orthogonal test of four factors and three levels was designed,and the optimum ratio of both intensity and working performance was obtained.By the research on mixture ratio design performance impact factors,the sand ratio,dosage of fly ash and water gel ratio on concrete working performance and mechanical properties of mixture,the influence of the experimental results show that for both big liquidity,good working performance and strength of LC40 pumping high strength lightweight aggregate concrete,the initial cement dosage should be 490 kg/m3 to 480 kg/m3,water/cement ratio control at about 34%,15% dosage of fly ash the working performance and mechanical performance is best;For the control of concrete dry apparent density,sand ratio should not be more than 42%,with the increasing sand ratio,the slump of concrete mixture decreases,slump loss decreases when the,and sand ratio increase is too large,will reduce the compressive strength of concrete;In the case of fly ash content of 15%,the mechanical properties of concrete and the work performance of the mix are thebest.The cement ratio was gradually reduced,the working performance of the mixing was gradually reduced,and the compressive strength of concrete gradually increased with the decrease of the cement ratio,but the increase was small and stable in the later stage.Combined with the test process and engineering application,the measures to control the buoyancy of lightweight aggregate are discussed from six aspects.Using SEM to light sets and light aggregate-cement interface microstructure analysis,preliminary reveals the reasons of high early strength of lightweight aggregate concrete,and discussed the light aggregate "micro pump" effects on aggregate to cement interface.Above all,high-strength pumping light aggregate concrete has good work performance and mechanical performance,the test results of high strength lightweight aggregate concrete pumping provides a certain reference value for engineering applications.