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高   静 ，张   起

（ 河南省地质矿产勘查开发局第三地质矿产调查院 ，河南 郑州 450000)

摘   要：以某地水库大坝基坑岩土为研究对象，进行坝坡基坑岩土非线性压力破坏下应力敏感性试验研究。基于岩土渗透率和渗透系数指标，利用非线性破坏规则分析坝坡基坑岩土的应力敏感性。结果表明：岩土非线性参数对坝坡基坑地基承载力影响较大， 随着岩土曲率系数增大，承载力系数逐步降低，其中重度影响系数对岩土极限承载力的影响不敏感；渗透率与孔隙流体内压成正比，且围压较大时岩土渗透率受内压影响变化较小，应力不敏感，相反， 围压较小时岩土应力敏感性较强；在围压不同阶段，渗透系数对含石率变化的敏感系数曲线，随着含石率的增加呈现先降低后上升再下降的总体态势，含石率为 60% 时，岩土渗透系数对含石率变化敏感性最高，应力敏感性最高。

关键词：坝坡基坑岩土；非线性压力；敏感系数；应力敏感性；围压测试；渗透率

中图分类号：TU45            

文献标志码：A           

文章编号： 1005- 8249   (2024)  05- 0076- 05 

DOI:10. 19860/j.cnki.issn1005 - 8249.2024.05 .014

 

GAO Jing ,  ZHANG Qi

(The Third Geological and Mineral Investigation Institute of Henan Bureau of Geology

and Mineral Exploration and Development ,  Zhengzhou 450000 ,  China)

Abstract: Taking the rock and soil of a reservoir dam foundation pit as the research object, a stress sensitivity test was conducted on the rock and soil of the dam slope foundation pit under nonlinear pressure failure. Based on the indicators of rock and soil permeability and permeability coefficient, the stress sensitivity of the rock and soil in the dam slope foundation pit is analyzed using nonlinear failure rules. The results show that the nonlinear parameters of rock and soil have a significant impact on the bearing capacity of the foundation pit of the dam slope. As the curvature coefficient of the rock and soil increases, the bearing capacity coefficient gradually decreases. Among them, the severe influence coefficient is not sensitive to the ultimate bearing capacity of the rock and soil; The permeability is directly proportional to the internal pressure of the pore fluid, and when the confining pressure is high, the permeability of the rock and soil is less affected by the internal pressure and less sensitive to stress. On the contrary, when the confining pressure is low, the stress sensitivity of the rock and soil is stronger; At different stages of confining pressure, the sensitivity curve of permeability coefficient to changes in rock content shows an overall trend of first decreasing, then increasing, and then decreasing with the increase of rock content. When the rock content is 60%, the sensitivity of rock and soil permeability coefficient to changes in rock content is the highest, and the stress sensitivity is the highest.

Keywords:rock and soil of dam slope foundation pit; non linear pressure;confining pressure test;pressure bearing sensitivity;sensitivity coefficient;permeability 

 

作者简介： 高   静(1982—), 女，本科，工程师，研究方向：水工环地质等相关专业的应用。

收稿日期：2023-11-15