The Effect Of EPS Volume Fraction On The Physical And Mechanical Properties Of EPS Concrete

Expanded Polystyrene(EPS)concrete is a new type of lightweight concrete,in which EPS is used as aggregate instead of traditional aggregate including sand and coarse aggregate.Compared with traditional concrete,EPS concrete has some remarkable advantages,such as lightweight,good ductility and thermal insulation.Therefore the engineering application of EPS concrete is wide in walls,heat insulation and others.In recent years,researchers have carried out a series of studies on EPS concrete in the world.Based on previous studies,further studies have been carried out in this thesis,and the main work including:(1)Via precise mix proportion designed in this paper,EPS concrete specimens with EPS volume fraction from 29% to 56% have been prepared,and the relationship of EPS concrete's measured dry density and design density has been compared and studied.The relationship of EPS concrete's measured dry density and measured humid density has been studied.The expression of function relationship between measured value of dry density and EPS's volume fraction has been established for EPS concrete for designing the density of EPS concrete expediently.(2)Based on accumulative distribution area and average size of EPS distributed in upper,mid and lower zone of EPS concrete's,floatation index and uniformity index of EPS have been presented and the uniformity of EPS distributed in EPS concrete has been characterized.EPS's floatation index and uniformity index have been computed in EPS concrete containing different EPS's volume fraction by using Adobe Photoshop CS6 and Image-Pro Plus,then the uniformity of EPS distributed in EPS concrete has been characterized quantificationally.(3)Development law of early age strength of EPS concrete has been studied by comparing compressive strength of EPS concrete cured 3 days and 28 days in standard conditions.The relationship of EPS concrete's compressive strength and EPS's volume fraction,the influence of curing conditions on EPS concrete's compressive strength and the influence of EPS's volume fraction on EPS concrete's static compressive strength elasticity modulus have been studied as well.(4)In this paper,the morphology characteristics of EPS concrete's ITZ cured in standard and accelerated conditions,and the change of EPS concrete's ITZ before and after compression failure have been studied respectively by using the method of stereomicroscope micro-examination,and the characteristics of EPS concrete's ITZ were obtained.(5)The influence of EPS's volume fraction on EPS concrete's thermal conductivity has been studied via hot-wire method;the law of EPS concrete's drying shrinkage has been studied by means of surface-type strainometer;EPS concrete's water absorption and the influence of EPS's volume fraction on EPS concrete's water absorption have been studied.