摘要
以上海某植物园加筋土工程为背景,通过一系列室内拉拔和直剪试验,研究了单、双向塑料土工格栅与不同填料(黏性土、砂土)的界面作用特性,对比分析了单、双向格栅的加筋效果和界面剪应力的不同发挥机制,探讨了填料密实度、垂直应力、拉拔速率对界面参数的影响,并就拉拔试验和直剪试验结果进行了对比分析。结果表明,对于单向格栅加筋工况,拉拔曲线和直剪曲线通常表现为应变软化型。然而对于双向格栅加筋工况,其曲线一般表现为应变硬化型;对于双向格栅加筋工况,填料对格栅的嵌锁咬合力增强,宏观上表现为较高的界面黏聚力,加筋效果优于单向格栅;填料密实度、垂直应力、拉拔速率对筋土界面特性具有影响,但其影响程度和机制与填料性质有关。
Based on a large reinforced soil project in Shanghai, a series of pull-out tests and direct shear tests were carried out to study the interface characteristics between uniaxial/biaxial plastic geogrids and different soils. The effects of reinforcement and the mechanism for the developing of interface shear stress were comprehensively compared between uniaxial and biaxial plastic geogrids. The influences of soil density, vertical stress level and displacement rate on the interaction characteristics were also discussed. It is found that the force-displacement curves of pull-out and direct shear tests for uniaxial geogrid reinforcement generally exhibit strain soften characteristics; but those for biaxial geogrid reinforcement often demonstrate strain harden characteristics. The effects of biaxial geogrid reinforcement are better than uniaxial geogrid reinforcement because of distinct enchasing force between soil and biaxial geogrid. Soil density, vertical stress level and displacement rate will all influence the interface characteristics; but the extent and mechanism of those influences are different for different soils.
出处
《岩土力学》
EI
CAS
CSCD
北大核心
2009年第8期2237-2244,共8页
Rock and Soil Mechanics
基金
上海市教委支出预算项目(No.2008076)
上海高校选拔培养优秀青年教师科研专项基金(No.shs08004)
上海海事大学重点学科建设项目(No.2009445878)
上海现代建筑设计集团科研课题(No.07-1A类-0027-基)
