大厚度湿陷性黄土现场浸水试验研究  

Field immersion test on self-weight collapsible loess site with large thickness

作　　者：徐西久 范江涛 袁可佳 白晨帆 蒋应军[2] XU Xijiu;FAN Jiangtao;YUAN Kejia;BAI Chenfan;JANG Yingjun(Shaanxi Xihan Intercity Railway Co.Ltd.,Xi′an 710064,China;School of Highway,Chang′an University,Xi′an 710064,China)

机构地区：[1]陕西西韩城际铁路有限公司,陕西西安710064 [2]长安大学公路学院,陕西西安710064

出　　处：《西安建筑科技大学学报（自然科学版）》2023年第6期849-857,共9页Journal of Xi'an University of Architecture & Technology(Natural Science Edition)

基　　金：陕西省科技计划基金资助项目(18-02K,19-27K)。

摘　　要：在陕西省渭南市合阳县大厚度自重湿陷性黄土地基上进行了现场试坑浸水试验,深入研究了原状黄土地基的湿陷性和渗流特性,揭示了地表及深部土层沉降量随时间的变化特征、浸水范围及湿陷范围.结果表明,试坑地表、深部土层沉降量随时间变化曲线都呈现慢-快-慢-稳定的特点,湿陷变形发展过程都经历4个发展阶段,分别是初期平缓段、迅速变形段、过渡段及后期平缓段,黄土的自重湿陷变形基本发生在迅速变形段和过渡段.土层湿陷范围小于饱和范围,黄土在饱和条件及上覆饱和自重应力作用下也不会发生湿陷.提出了路基防排水宽度为12 m的建议,该结论可为西韩城际铁路路基排水及地基处治提供参考.The collapsibility and seepage characteristics of in-situ loess foundations were investigated in depth by conducting on-site test pit immersion tests on a large-thickness self-weight collapsible loess foundation in Heyang County,Weinan City,Shaanxi Province,revealing the change characteristics of surface and deep soil settlement with time,the extent of immersion and collapsibility range.The results show that the settlement curves of surface and deep soil layers in the test pits show a slow-fast-slow-stable trend over time.The development process of collapsible deformation goes through four development stages,namely the initial gentle section,rapid deformation section,transitional section and mid-term gentle section,and the self-weight collapsible deformation of loess basically occurs in the rapid deformation section and transitional section.The collapsible range of the soil layer is less than the saturated range,and the loess will not collapse under the saturated condition and the overlying saturated self-weight stress.It is proposed that the width of roadbed drainage prevention is 12 m and the depth of foundation treatment is 15m,and the conclusion can provide reference for the roadbed drainage and foundation treatment of Xi′an-Hancheng Intercity Railway.

关 键 词：大厚度自重湿陷性黄土 现场试坑浸水试验 湿陷性 湿陷变形特征 渗流特性 

分 类 号：TU444[建筑科学—岩土工程]