不同养护龄期下分层胶结充填体力学特性研究

Study on the Mechanical Properties of Layered Cemented Backfill Under Different Curing Ages

为探究养护龄期对分层胶结充填体力学特性的影响,对不同养护龄期下的分层胶结充填体进行了单轴压缩试验,获得了分层胶结充填体的应力-应变曲线,分析了分层胶结充填体的峰值强度、弹性模量及强度折减系数。结果表明:分层胶结充填体与完整充填体具有类似的应力-应变曲线,各养护龄期下应力-应变曲线均分为4个阶段,但是不同养护龄期之间存在明显区别;分层胶结充填体的抗压强度和弹性模量随养护龄期的增加而增加;各养护龄期下的分层胶结充填体的强度折减系数均小于1,分层结构对其强度有明显的弱化效应,随着养护时间的延长,这种弱化效应减弱,因此,适当延长养护龄期有利于减弱分层效应。

In order to explore the impacts of different curing ages on the mechanical properties of the layered cemented backfill, uniaxial compression tests were carried out on the layered cemented backfill under different curing ages. The stress-strain curve of the layered cemented backfill was obtained, and the peak strength, elastic modulus and strength reduction coefficient of the layered cemented backfill were analyzed. The results are concluded as follows. Firstly, the layered cemented backfill has a similar stress-strain curve to the complete backfill, and the stress-strain curve at each curing age is divided into four stages, but there are obvious differences among different curing ages. Secondly, the compressive strength and elastic modulus of the backfill increase with the increase of the curing age. Thirdly, the strength reduction coefficient of the layered cemented backfill under each curing age is less than 1, and the layered structure has a significant weakening effect on backfill strength. With the extension of the curing time, the weakening effect is weakened. Therefore, the appropriate extension of the curing age is beneficial to reduce the stratification effect.