计算黄土卸荷湿陷量的模量折减法研究  

A modulus reduction method for calculating loess unloading collapse

作　　者：金鑫 王铁行[2] 张玉[1,3] 张猛 JIN Xin;WANG Tiehang;ZHANG Yu;ZHANG Meng(School of Civil and Architecture Engineering,Xi'an Technological University,Xi'an,Shaanxi 710021,China;College of Civil Engineering,Xi'an University of Architecture and Technology,Xi'an,Shaanxi 710055,China;Shaanxi Key Laboratory of Loess Mechanics and Engineering,Xi'an University of Technology,Xi'an,Shaanxi 710048,China)

机构地区：[1]西安工业大学建筑工程学院,陕西西安710021 [2]西安建筑科技大学土木工程学院,陕西西安710055 [3]西安理工大学陕西省黄土力学与工程重点实验室,陕西西安710048

出　　处：《岩石力学与工程学报》2021年第7期1473-1483,共11页Chinese Journal of Rock Mechanics and Engineering

基　　金：国家自然科学基金资助项目(11802218);陕西省科技计划项目(2019JQ-432);西安理工大学陕西省黄土力学与工程重点实验室项目(LME201801)。

摘　　要：黄土卸荷湿陷现象普遍存在于湿陷性黄土场地试坑和桩间土浸水等工况中,探究卸荷湿陷影响下的黄土湿陷量计算方法对于在保证黄土工程稳定安全的前提下,提高设计合理性、节约资金具有重要意义。为实现黄土卸荷湿陷量的快速计算分析,首先根据黄土恒载湿陷试验结果进行反算分析,利用黄土遇水后变形模量降低的特性,建立恒载条件下黄土湿陷系数与模量折减系数的对应关系。进一步对卸荷湿陷试验结果进行反算分析,建立卸荷条件下黄土卸荷湿陷系数与模量折减系数的对应关系。根据湿陷系数与卸荷湿陷系数的相关关系得到计算黄土卸荷湿陷量的模量折减法。然后利用黄土卸荷湿陷系数与模量折减系数在卸荷量为零时可退化至恒载湿陷条件下的对应关系,对模量折减法的合理性进行退化验证。并将其用于桩间黄土湿陷时的桩侧负摩阻力计算以验证可靠性。研究成果为黄土卸荷湿陷变形分析提供了便捷途径,并对湿陷性评价体系进行一定的补足和验证。Loess unloading collapse widely exists in test pits and the loess between piles.On the premise of ensuring the safety of loess engineering,it is important to boost the economy and rationality of engineering projects.To achieve efficient calculation of loess unloading collapse,the inverse analysis of loess collapse tests under constant loads is carried out,and the relationship between the collapse coefficient and the modulus reduction coefficient under constant loads is established according to that the deformation modulus of loess decreases after immersion.Furthermore,the inverse analysis of loess unloading collapse tests is performed,and the relationship between the unloading collapse coefficient and the modulus reduction coefficient is proposed.A modulus reduction method for calculating the loess unloading collapse is obtained with the help of the relationship between the collapse coefficient and the unloading collapse coefficient,and verified through evaluating the relationship between the unloading collapse coefficient and the modulus reduction coefficient by setting the unloading amount equal to zero to simulate the constant loading case.The research results provide an efficient way for analyzing loess unloading collapse and improve the collapse evaluation system.

关 键 词：土力学 黄土湿陷 卸荷作用 模量折减 卸荷湿陷量 

分 类 号：TU44[建筑科学—岩土工程]