黏土与EPS颗粒混合轻质土的动力变形特性试验研究

通过室内动三轴试验研究了黏土与EPS颗粒混合轻质土(LCES)在动荷载作用下的变形特性,着重分析了围压、水泥含量和EPS掺入比的影响。结果表明:LCES的动应力应变关系符合双曲线关系;在相同的动应力作用下,LCES产生的应变随着围压和水泥含量的增大而减小;在动应变相同的情况下,随着围压和水泥含量的增大,LCES的割线动弹性模量Esec增大而阻尼比λ减小;EPS掺入比对LCES的动力变形特性的影响相对较小,不同EPS掺入比的σd–εd曲线、Esec–εd曲线和λ–εd曲线都发生了相交,交点前后EPS掺入比的大小对LCES变形特性的影响趋势是截然相反的,交点处的动应变值εint一般在0.5%～3.0%范围内,其大小与LCES的配比以及围压有关。

Experimental study on dynamic deformation characteristics of lightweight clay-EPS beads soil

The dynamic deformation properties of lightweight clay-EPS beads soil（LCES） were studied using triaxial apparatus,and the effort was focused on the influence of confining pressure,cement content and EPS content.It was indicated that its dynamic stress-strain curve was of hyperbolic type.The strain of LCES decreased with the increasing confining pressure and the cement content under the same dynamic stress.Under the same dynamic strain,the dynamic secant elastic modulus,Esec of LCES increased and the damping ratio λ decreased with the increasing confining pressure and cement content.Compared with the confining pressure and cement content,there was little effect of EPS content on the dynamic deformation of LCES.The curves of σd–εd,Esec–εd and λ–εd with different EPS contents intersected with each other respectively,and the trend of LCES deformation characteristics was inversely proportional to EPS content near the intersection.The value of dynamic strain at the intersection εint was about 0.5%³.0%,and its magnitude to was related to the mixing proportions and confining pressure.