堆石在平面应变条件下的强度和应力—应变关系

Strength and Stress-Strain Relationship of Rockflll under Plane Strain Condition

应用大型平面应变仪,进行了灰岩及细砂岩两种堆石的风干料及饱和固结排水平面应变试验。试验结果表明:1.堆石在平面应变条件下的强度比三轴试验强度高;2.饱和试样强度低于风干料试样强度;3.平面应变条件下的应力-应变关系与三轴试验结果相比较,差别较大,前者呈明显的应变软化特性;4.平面应变条件下堆石泊松比基本上是一常数,而且小主应力σ_3对它影响较小。

The rockfill materials of limestone and fine sandstone were tested by large scale plane strain apparatus in air dry and saturated state respectively. These test results revealed that:(l)the shear strength of rockfill materials under plane strain condition is higher than that in triaxial state, (2)the strength of rockfill material in saturated state is lower than that in air dry state, (3) in comparison with triaxial tests, the strain softening behavior is more obvious in plane strain state, (4)the Poisson's ratio of rockfill material in plane strain state is almost a constant, and it is less affected by confining pressure σ3.