基于扁铲侧胀试验计算黏性土的超固结比与静止土压力系数  

Calculation of over-consolidation ratio and the earth pressure at rest coefficient of cohesive soil based on flat dilatometer test

作　　者：易志强 Yi Zhiqiang(Shenzhen Bureau of Geology,Shenzhen 518000,Guangdong,China)

机构地区：[1]深圳市地质局,广东深圳518000

出　　处：《地质学刊》2022年第3期320-326,共7页Journal of Geology

基　　金：国家自然科学基金项目“SBISP-易扰动土界面摩擦特性及其力学响应研究”(41772314)。

摘　　要：依托广州地铁18号线横沥站—番禺广场站区间岩土工程勘察项目,通过数值模拟方法进行扁铲侧胀探头贯入土体的三维有限元模拟,采用总应力法进行分析,尝试研究侧胀水平应力指数K_(D)与静止土压力系数k_(0)、超固结比OCR的相互关系,提出了适用于黏性土的静止土压力系数k_(0)、超固结比OCR的计算公式,并将计算结果与现场实测数据进行比较。研究表明:使用弹塑性本构模型并遵循最大切应力失效准则的总应力分析方法可以很好地模拟扁铲侧胀的贯入过程,经验公式获得的计算结果与现场数据及室内试验结果具有良好的一致性。Based on the geotechnical engineering survey project from Hengli Station to Panyu Square Station of Guangzhou Metro Line 18,the three-dimensional finite element simulation of flat shovel lateral dilation probe penetrating into soil was established by numerical simulation method.The total stress method was used for analysis in order to study the relationship between lateral dilation horizontal stress index K_(D),earth pressure at rest coefficient k_(0) and over-consolidation ratio(OCR).The calculation formulas of earth pressure at rest coefficient k_(0) and over-consolidation ratio(OCR)for cohesive soil were proposed,and the calculated results were compared with the field data.The results show that the penetration process of flat shovel lateral dilation can be well simulated by using the total stress method which is based on the Tresca constitutive model and follows the Tresca yield criterion.The calculation results obtained by the empirical formula are in good agreement with the field data and indoor experiment data.

关 键 词：扁铲侧胀试验 黏性土 超固结比 侧胀水平应力指数 静止侧压力系数 

分 类 号：P642.11[天文地球—工程地质学]