土工合成材料加筋边坡剪切屈服区特性和破坏模式

PERFORMANCES OF SHEAR ZONES AND FAILURE MODES IN GEOSYNTHETIC REINFORCED SLOPES

用有限元分析方法模拟筋材与土的相互作用,分析加筋边坡的稳定性,研究边坡加筋后剪切屈服区特性和破坏模式的变化,以及加筋层数和筋材拉伸模量的影响。结果表明,加筋后边坡的剪切屈服区和破坏模式发生改变,筋材拉伸模量和加筋密度不同,加筋边坡的破坏形态也不相同。筋材拉伸模量过低时,加筋边坡的剪切屈服区与素土边坡接近,加筋的稳定效果不明显,即便增大加筋密度对边坡安全系数的提高也不大;随着筋材拉伸模量增大,加筋的稳定作用增强,且随加筋层数增加,边坡的剪切屈服区宽度增宽,并向边坡内部和基础发展;对于加筋密度相同的加筋边坡,随着筋材拉伸模量的增大,边坡将呈现三种典型的破坏模式。

Finite dement analyses are employed to simulate soil-reinforcement interaction, and to investigate the performances of shear zones and failure modes in reinforced soil slopes, as well as the influences of reinforcement modulus and density. The results show that the slopes with and without reinforcements differ significantly on the failure modes, and the reinforcements with different density and modulus also result in various performances of shear zones. With very low reinforcement modulus, the shear zones and failure modes in reinforced slopes approach those in soil slopes, and the stabilizing effects of the reinforcement appear insignificant even with increasing reinforcement density; With reinforcement modulus increasing, the influences of reinforcement become more significant. The widths of the shear zones increase with the increasing density and modulus of the reinforcement and tend to move into the slopes and the foundations. The results also indicate that with the soil strength and density of the reinforcement kept constant in the reinforced slopes, there exist three failure modes as the reinforcement modulus increases.