砂土-格栅筋土界面特性的本构模型研究

发布时间：2018-02-24 14:32

本文关键词： 粗砂格栅界面本构模型峰值前峰值后剪胀性　出处：《岩土力学》2014年S2期 　论文类型：期刊论文

【摘要】：基于砂土与土工格栅、土工织物界面的室内大型直剪试验,分析了两种不同界面的力学性能。试验结果表明,峰值、残余剪切应力与界面剪胀性曲线存在一定的联系,即峰值强度通常会发生在界面相对减缩过程结束和残余剪切强度发生在界面的相对剪胀过程结束。加载过程中由于土工合成材料的逐步磨损、褶皱或者断裂导致了筋土界面强度出现较为明显的强度软化现象,在界面抗剪强度的研究中不可忽略。在试验基础上提出一种能够描述筋土界面力学性能的组合本构模型,该模型包含4个关系式:(1)峰值、残余强度包络线;(2)强度峰值前的双曲线模型;(3)强度峰值后的位移软化模型;(4)反映剪胀特性的界面剪胀模型。该组合模型的预测结果与直剪试验结果吻合较好,表明所用模型是合理的。
[Abstract]:The mechanical properties of two different interfaces are analyzed based on the indoor direct shear tests of sand, geogrid and geotextile interface. The experimental results show that the peak value, residual shear stress and shear dilatancy curve of the interface are related to each other. That is, the peak strength usually occurs at the end of the interface relative reduction process and the residual shear strength at the end of the interface relative shear expansion process. Fold or fracture leads to obvious strength softening phenomenon at the interface of reinforced soil, which can not be ignored in the study of interfacial shear strength. On the basis of experiments, a combined constitutive model which can describe the mechanical properties of the interface of reinforced soil is proposed. The model consists of four relational expressions: 1) peak value. The hyperbolic model before the peak value of the residual strength is a hyperbolic model and the displacement softening model after the peak value of the residual strength is a model of interfacial shear expansion, which reflects the characteristics of shear expansion. The predicted results of the combined model are in good agreement with the results of the direct shear test, and the predicted results of the combined model are in good agreement with the results of the direct shear test. It is shown that the model is reasonable.
【作者单位】：温州大学建筑与土木工程学院;温州大学浙江省软弱土地基与海涂围垦工程技术重点实验室;连云港职业技术学院建筑工程学院;
【基金】：国家自然科学基金(No.51278383,No.51238009) 国家重点基础研究发展计化(No.2011CB411907) 浙江省自然科学基金(No.Y1110751) 温州市科技计划项目(No.S20100057) 浙江省科技计划项目(No.2010C33182)
【分类号】：TU531.7

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