三轴试验测定掺砾心墙料邓肯模型参数简化方法的探讨

提出一种能够缩短掺砾心墙料大三轴排水剪试验时间的方法,即降低掺砾心墙料中细粒的含量。掺砾心墙料的强度和变形主要取决于粗粒部分,试验表明,适量降低细粒的含量,没有改变原级配试样应力应变曲线的基本特征。而细粒含量的降低,可以有效地提高试验过程中的排水速率。给出了降低的细粒含量与渗透系数之间的关系,给出了降低细粒含量的掺砾心墙料大三轴试验步骤,以及确定邓肯模型参数的简化方法。

Simplified method for measuring the Duncan model parameters of gravel-mixed core materials by means of triaxial tests

A method is proposed that shortening the time of large scale triaxial draining shear tests on gravel-mixed core materials by reducing the content of fine grains. The characteristics of strength and deformation of gravel-mixed core materials depend on the coarse grains. It is found that fundamental features of stress and strain curves of soil specimens do not change even though appropriate fine grains are reduced. With the decreasing amount of fine grains, the drain velocity in triaxial tests is improved considerably. The relationship between the content of fine grains which are reduced and the permeability coefficient of soil specimens is derived. The procedure of large scale triaxial tests on gravel-mixed core materials and the way to obtain the Duncan model parameters are given.