黄土与土工格栅界面剪切力学特性研究

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中图分类号：034；TU54 文献标志码：A 文章编号：1000-4939（2025）06-1340-13

Abstract：The objective of this paper is to study the mechanical characteristics of the interface between loess and geosynthetics，in hope of providing targeted suggestions for the design of reinforced loess projects. A large-scale interface shear apparatus was used to conduct direct shear tests on the geogrid-loess interface to study the effects of the moisture content and compaction degree of loess on the shear stress-shear displacement relationships，shear strength indices，and thickness of shear band of the geogrid-loess interface. The mechanism of the efects was analyzed，and the constitutive model of the geogrid-loess interface was discussed.The test results show that as the moisture content increases （not exceeding the plastic limit）， the shear stress-shear displacement curves of the geogrid-loess interface change from softening type to hardening type.The interface cohesion and friction angle significantly decrease with the increase of the moisture content，and thus the interface shear strength decreases accordingly.The thickness of shear band increases with the moisture content. The compaction degree of loess has litle influence on the shear strength of the geogrid-soil interface，but it afects the thicknessof shear band significantly.The thickness of shear band increases greatly when the compaction degree reaches 90% .Hence，the compaction degree of the backfill of reinforced loess engineering should not be less than 90% . The thickness of the shear band of geogrid-loesinterface decreases continuously along the shear direction，with a maximum thickness of 3 cmapproximately.This indicates that the shear band between the reinforcement and soil is the thinnest at the facing column in reinforced loess retaining wals.Hence，a flexible or integral facing column is recommended to be used in reinforced loess retaining walls.The hyperbolic interface constitutive model can effectively reflect the shear behavior of the geogrid-loess interface.

Key words ：loess；geogrid；reinforcement-soil interface；moisture content；degree of compaction； shear band

土工合成材料与土体间的摩擦、嵌锁作用可提高土体的整体强度，是岩土工程领域常见的加筋材料之一，广泛用于加筋挡墙、加筋边坡和加筋地基等加筋土工程。（剩余17217字）