A Four-parameter Multi-axial Strength Criterion forLightweight Aggregate (LWA) Concrete

摘要

Concrete utilized in engineering structures is usually subject to thernaction of multi-axial stress. The strength theory of concrete isrnsignificant to structure design and saving of construction material.rnExperimental results have revealed that lightweight aggregate (LWA)rnconcrete represents platform flow plasticity under high compressivernstress. The ultimate strength surface of LWA concrete under multi-axialrnstress intersects with the hydrostatic stress axis at two different points,rnwhich is completely different from that of the normal concrete as thernultimate strength surface is open-ended. So the strength criterion aimedrnat normal concrete cannot fit LWA concrete. In this paper, a fourparameterrnmulti-axial strength criterion for LWA concrete is presented.rnThe strength envelope of the proposed model in the deviatoric planernadopted elliptic curve similar to that of Willam-Warnke model, and therntensile and compressive meridians are represented by quadraticrnfunctions with four parameters. Two methods can be used for therndetermination of the four parameters and their merits and drawbacksrnare compared by the analysis of experimental data.