Experimental Study On Compressive Mechanical Property Of Engineered Cementitious Composites

Engineered Cementitious Composites (ECC) has the characteristics of highstrength, high ductility and great energy absorption, which can improve the ductility ofthe concrete structure?the capacity of damage resistance significantly and enhance theseismic performance and crack resistance when apply the materal in the key parts ofconstruction, such as coupling beams, column base, the beam-column joints and theyield hinge region of shear wall. So it has broad application prospects. In order to studyand promote the ECC, it is necessary to study its basic mechanical property, and as oneof the most basic mechanical properties of the materials, the compressive mechanicalproperty has great research significance. In addition, as there is no coarse aggregate inthe ECC, its interface features is different from ordinary concrete obviously, andcombined with a large number of PVA fiber evenly dispersed in the matrix, itscompressive mechanical property is different from ordinary concrete. Therefore, it isnecessary to study the compressive mechanical property of ECC.On the basis of the previous research, the paper adopts the single-factor experimentto study the compressive strength, the flexural strength, the relationship between thetwo strength, the size effect and the compression constitutive model of ECC, the maincontents of the paper are as follows:(1) Based on the previous research of our group, the paper study the process ofcompression failure, the crack pattern, the failure mechanism and the process of flexuralfailure, then it study the influence of4kinds of factors such as fiber content by volume,water binder ratio, fly ash content and sand binder ratio to compressive performance ofECC, so that it can provides the basis for the design and engineering application.(2) Based on the previous research of our group, the paper study the relationship between cubic compressive strength and axial compressive strength and the strengthbetween different sizes, that is determine the coefficient of size effect and the ratiocoefficient between cubic compressive strength and axial compressive strength ofductility fiber reinforced concrete.(3) Based on the previous research of our group, the paper study the axialcompressive of prisms and its compressive stress-strain curve of ductility fiberreinforced concrete, and then analysis the influence of fiber content by volume, waterbinder ratio, fly ash content and sand binder ratio to the curve and its parameters andputs forward the corresponding constitutive model of compression, so that it canprovide theoretical basis for the structure design and the nonlinear numericalsimulation.