水位骤降环境土工织物加固土坡的离心模型试验

Centrifuge model test of geotextile-reinforced soil slopes during drawdown

土工织物是土石坝堤和土坡的常用加固手段,其在水位骤降环境下对土坡的加固机理尚未阐明。该文进行了水位骤降离心模型试验,观测了土工织物加固土坡与素土坡的变形破坏过程。试验结果表明:土工织物显著减小了土坡的位移并提高了土坡稳定性;土工织物存在着与水位变化无关的分界点,其内侧和外侧分别表现为约束土坡变形和被土坡约束的不同性质;土工织物通过其与土坡的相互作用,将土坡内部的约束传递到坡外部,使土坡的变形分布更均匀,阻碍了"变形局部化发展到一定程度"这一滑裂面形成的前提条件的发生。

Geotextiles are widely used to reinforce embankments and soil slopes. However,the geotextile reinforcement mechanism during drawdown is not well understood.Centrifuge model tests were conducted to observe the deformation and failure of geotextile-reinforced and unreinforced slopes during drawdown.The test shows that the geotextile significantly reduces the deformation and increases the slope stability.The slope deformation is restricted by the geotextile for water levels lower then a critical point and anchored by the geotextile at higher levels. The geotextile transmitted the interior restriction to the exterior of the slope via the soil-geotextile interaction. Thus, the deformation was more uniformly distributed. The geotextile delayed deformation localization,the precondition for slope failure.