基于毛管浸润技术的岩石孔隙率无损测试  

Nondestructive testing of porosity of rock based on capillary infiltration technique

作　　者：刘杰[1] 黄飞 杨渝南[1] 杨绪 LIU Jie, HUANG Fei, YANG Yu-nan, YANG Xu(Key Laboratory of Geological Hazards, Ministry of Education, Three Gorges Reservoir Area, Three Gorges University, Yichang, Hubei 443002, Chin)

机构地区：[1]三峡大学三峡库区地质灾害教育部重点实验室,湖北宜昌443002

出　　处：《岩土力学》2018年第3期1137-1144,共8页Rock and Soil Mechanics

基　　金：成都理工大学地质灾害防治与地质环境保护国家重点实验室开放基金项(No.SKLGP2016K023);长江科学院开放研究基金资助项目(No.CKWV2016377/KY);国家科技支撑计划项目(No.2015BAB07B08);国家自然科学基金项目(No.51439003;No.51579138)~~

摘　　要：以岩石主要表征参数孔隙率变化作为岩石损伤分析的着力点,开发了一种无损的定量分析岩土损伤的毛管浸润技术。通过对孔隙土体的毛管浸润试验研究了浸润速率、浸润面积和浸润深度随孔隙率的变化规律,提出了毛细管束模型并对毛管浸润技术的机制进行了深入研究。相对于现有的有损且不可重复测量技术,毛管浸润技术操作简便,成本低廉,且对于特定的损伤岩体,可以通过试验建立滴定参数与力学参数的联系。基于毛管束模型中毛管浸润对孔隙体下部的作用,分别建立了毛管浸润的圆柱模型1、圆柱模型2和球状模型,由上部液柱下降高度(35)h以及表面浸润面半径a推算下部孔隙体中液体浸润深度L。根据实际孔隙土体的浸润参数对上述模型进行验证计算,指出球状浸润模型能够更好地模拟实际毛管浸润过程中液体的浸润深度情况。基于毛细管束模型,由浸润参数即浸润深度与浸润速率的关系,分别建立了3种模型的孔隙率计算公式。针对球缺模型的孔隙率n?进行验算,发现计算值与实测孔隙率的误差不超过10%,指出在求解一般精度要求下的孔隙率时,用该孔隙率公式计算的结果是合理有效的。Taking the rock porosity as the focal point of rock damage analysis, this study is to develop a capillary infiltration technique for non-destructive quantitative analysis of the geotechnical damage. Moreover, variations of the capillary infiltration rate, infiltration area and depth of infiltration are investigated by changing the porosity in capillary infiltration tests. The capillary bundle model is proposed and the mechanism of capillary infiltration technique is also analysed in depth. Compared with the existing damage and non-repeatable measurement technologies, this technology is easy to operate and low cost. In particular, for a rock with specific damage, we can establish a relationship between titration parameters and mechanical parameters. In addition, the capillary model 1, the cylindrical model 2 and the spherical model are put forward, respectively, by considering the effect of capillary infiltration on the lower part of the capillary body in the capillary bundle model. The depth of the liquid infiltration in the lower porosity L is estimated from the upper liquid column descending height（35）h and the surface of infiltration radius a. According to the infiltration parameters of the actual pore soil, the validation of the above model is verified. In addition, the result indicates that the spherical infiltration model can better simulate the infiltration depth of the liquid during the process of capillary infiltration. Based on the capillary bundle model, the porosity calculation formulas of three models are separately deduced by the infiltration rate, which is the relationship between the infiltration depth and the infiltration rate. The calculated porosity n？ of the spherical cap model is examined with the measured porosity, and its error is less than 10%. Therefore, the results calculated by this porosity formula are reasonable and effective for general accuracy requirements.

关 键 词：毛管浸润技术 孔隙率:毛管束模型 柱状模型 球状模型 

分 类 号：TU452[建筑科学—岩土工程]