密实度对砂卵砾石料强度及变形特性的影响

为研究试样相对密度对砂卵砾石料强度及变形特性的影响,对4组不同相对密度的砂卵砾石料进行不同围压下的中型三轴固结排水剪切试验。试验结果表明:在试验的相对密度范围内,随着围压增大,相对密度小的试样应力应变曲线硬化特征逐渐明显,而相对密度大的试样无论围压大小,应力应变曲线都呈应变软化型;试样在剪切过程中均表现出不同程度的剪胀性;试样抗剪强度指标φ和φ0随着试样相对密度Dr增大而增大,c和Δφ随Dr增大而减小,并建立了试样抗剪强度与相对密度的函数关系式;割线模量、切线体积模量都随Dr增大而增大,可近似用线性关系表示。

Density effects on strength and deformation behaviour of sandy gravel

Triaxial tests of the sandy gravel with four different densities have been performed under different confining pressure in order to investigate the effects of relative density upon strength and deformation behaviour of the sandy gravel. The test results show that, within the range of the relative density of the experiments, the hardening characteristic of the stress-strain curves have become distinct with the increase of the confining pressure when the relative density is low; and the stress strain curves appear as strain softening regardless of the value of confining pressure when the relative density is high. Different degrees of the dilatancy are showed during the lab tests. With the increase in the density, the values of φ and φ0 increase, and the values of c and Δφ decrease, therefore, a functional relationship between them has been established. The values of E1 and Bt show a linear growth with the increase of Dr because the secant modulus E1 and the volume modulus Bt would increase with the increase of Dr.