88水科学与工程技术2023年第4期基坑粉黏土体在土钉锚固下力学特征变化研究杨娜(河北省迁安市水利局,河北迁安064400)摘要:通过开发土钉模拟试验装置,对土钉粉质黏土试样开展室内力学试验及SEM细观扫描。试验表明,干湿路径差异化下,其应力应变趋势特征不同;同一种干湿路径在不同围压下,仍保持一致的应力应变特点,干湿次数不会影响应力应变趋势。在干湿不同路径下,土颗粒与土钉之间的连接性会有明显差异,土颗粒呈独立游离;土体裂隙数量与干湿次数的关系可用指数函数表示,为土钉复合土的力学试验研究及基坑工程设计提供参考。关键词:基坑;土钉;力学;试验中图分类号:TU411D01:10.19733/j.cnki.1672-9900.2023.04.25Theinfluenceofmechanicalcharacteristicsofsiltyclaysoilin(Qian'anWaterResourcesBureau,HebeiProvince,Qian'an064400,China)Abstract:Throughthedevelopmentofsoilnailingsimulationtestequipment,thelaboratorymechanicaltestandSEMscanningofsoilnailingsiltyclaysampleswerecarriedout.Theexperimentalresultsshowthatthestress-straintrendcharacteristicsaredifferentunderdifferentdryandwetpaths.Underdifferentconfiningpressures,thesamedryandwetpathstillmaintainsthesamestress-straincharacteristics.Incontrast,thenumberofdryandwettimesdoesnotaffectthestress-straintrend.Underdifferentpathsfromdrytowet,theconnectivitybetweensoilparticlesandsoilnailsisobviouslydifferent,andthesoilparticlesareindependent.Therelationshipbetweenthenumberofcracksinsoilandthenumberofdryandwettimescanbeexpressedasanexponentialfunction.Thispapercanprovidereferenceforthemechanicaltestresearchandfoundationpitengineeringdesignofsoilnailingcompositesoil.Keywords:foundationpit;soilnails;dynamics;test基坑工程中,土体承载力学特征直接影响基坑支护、开挖工序等技术问题[1.2],讨论基坑土体力学特性,有助于揭示基坑支护结构承载力较弱、土体沉降等内在原因。贾佳[3]、张岩等[4]为研究基坑土体的力学特征,借助离散元仿真建模方法,分析土体离散元模型的细观变化,分析不同尺寸的裂隙变化,从离散元细观计算的角度,分析土体裂隙的生成演变及裂隙对宏观破坏影响。崔宏环等[5]、朱伟崇等[6]为研究干湿、冻融等不同物理作用下土体力学特征变化,借助室内试验设备,开展物理场耦合作用下土体力学...