滑坡模型试验γ透射法坡体水分测量精度探讨  

Study of Accuracy of γ-Ray Penetrance Method for Measuring Soil Water Content in Landslide Model Test

作　　者：李显平[1] 罗先启[1] 张振华[1] 

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：《三峡大学学报（自然科学版）》2008年第3期53-57,共5页Journal of China Three Gorges University：Natural Sciences

基　　金：国土资源部2004年科技专项计划项目(SDHZ2004072)

摘　　要：在运用γ射线透射法测量大型滑坡模型土体含水量的过程中,为了提高试验的精度,综合分析了影响γ射线透射法测量精度的多种因素.其中,重点分析了水的质量吸收系数μ对测量精度的影响以及影响μ值的各种客观因素.针对大型滑坡模型试验的特殊条件,提出了相应的应对措施,以提高γ射线透射法测量含水量的精度.γ射线透射法测量滑坡模型中部土体的含水量是比较准确的,但对于滑坡模型表层和底层土壤,其含水量的观测受γ射线层间分辨率及边界条件的影响,误差较大.实践结果表明,采用修正μ值的方法处理试验数据对于提高滑坡模型表层和底层土体含水量的测量精度是有效的.When using y-ray penetrance method to measure soil water content in the big model test, several influencing factors on measurement accuracy of the γ-ray penetrance method are analyzed comprehensively. Among which, focusing on the analysis of the factor of water mass absorption coefficient-μ and kinds of objectively influencing factors on μ. Some appropriate measures are proposed to improve soil measuring accuracy of γ-ray penetrance method in mind the special condition of the big model test. It is comparatively accurate to use γ-ray penetrance method to measure water content of the middle soil of large landslide modei; but the error is very high when measuring water content at the surface and the bottom soil of landslide model. The results of practice indicate that using correct μ value to treat the data of test can validly improve the accuracy of water content at the surface and the bottom soil of large landslide model.

关 键 词：γ射线透射法 模型试验 土壤含水量 精度 质量吸收系数μ 

分 类 号：TU411[建筑科学—岩土工程]