Research on in-situ measurement of unsaturated soil hydraulic properties by geo-tomography

降雨入渗特性的研究对边坡稳定性分析具有重要意义.在包气带中，水和空气共同占据多孔介质的孔隙中。饱和-非饱和渗流有限元法已被开发来解决这些现象。在该方法中，非饱和土壤水力特性是预测包气带渗流特性的基本数据。主要研究成果如下：（1）应用电法勘探方法获取地质剖面信息。利用野外非稳态测量资料，采用调幅图像分析和直方图均衡化技术，对轴对称三维层析成像方法估计的电阻率分布进行了描述。它不需要耗时的数据收集。(2)提出了基于轴对称三维层析成像技术和数值分析相结合的现场无损检测方法。

Investigation of the behavior of infiltration by rainfall are very important to analyze the slope stability. In vadose zone, the phase of water and air are together occupied in viod pores of porous media. The saturated-unsaturated seepage flow finite element approach has been developed to solve these phenomena. In this approach, the unsaturated soil hydraulic properties are essential data to predict the seepage behavior in the vadose zone.In this research, a new in-situ experimental methodology of determining unsaturated soil hydraulic properties is proposed. The main results in this research are as follows ;(1) Electric prospecting method is applied to obtain the information of geological profiles. Am image analysis incorporating the histogram equalization techniques is used to express the distribution of resistivity estimated by axis-symmetric three dimensional tomography method.Non steady state measurement data which are obtained in the filed are used in this approach. It dose not need time consuming data collection.(2) Nondestructive field testing methods are proposed by Axis-symmetric three dimensional tomography method and numerical analysis.