粗颗粒填料含水量的TDR测试方法研究  

Research on Water Content Measurement of Coarse-grained Particles Using TDR Technology

作　　者：王瀚霖[1,2] 许峰 陈仁朋[1,2] 吴进[1,2] 

机构地区：[1]浙江大学软弱土与环境土工教育部重点实验室,杭州310058 [2]浙江大学岩土工程研究所,杭州310058 [3]浙江省浙建房地产集团有限公司,杭州310012

出　　处：《三峡大学学报（自然科学版）》2014年第6期37-42,共6页Journal of China Three Gorges University：Natural Sciences

基　　金：国家自然科学基金杰出青年基金(51225804);国家自然科学基金高速铁路基础研究联合基金重点支持项目(U1234204)

摘　　要：我国高速铁路路基主体工程设计使用年限为100年.强降雨条件下,由于路基结构开裂,部分水分入渗到路基内部,引起灾变.开展高铁路基水分运移规律的研究成为必要,路基粗颗粒填料含水量的准确测试技术是关键.利用TDR测试基本原理,通过计算设计,自主研制了三针式TDR探头.对该探头探针长度和电导率C值做了相关标定实验,并按ASTM标准对余杭某路基粗颗粒填料参数作了相关标定,研究表明,填料体积含水量与介电常数关系符合Topp公式.最后,对一组渗透柱实验中压实度90%的粗颗粒填料的含水量进行了TDR测试,与烘干法作对比,两者质量含水量相对误差控制在10%以内,验证了该探头测试粗颗粒填料含水量的可行性和准确性.The designed service life of high-speed railway subgrade is 100years in China. Due to cracking of subgrade structure, part of rain water infiltrated into the subgrade to cause diseases under heavy rainfall. It is necessary to research the moisture migration in the subgrade. And accurate water content measurement of subgrade＇s coarse-grained particles becomes the key issue. This paper utilized the principle of TDR test and developed the three-rod TDR probe after calculation. Calibration experiments of the rod length and electric conductivity C have been conducted. Meanwhile, calibration test of Yuhang subgrade coarse particles has been finished according to ASTM standard. It is indicated that the relationship between volumetric water content and dielectric constant corresponded well with Topp formula. Finally, TDR tests of coarse-grained particles with compactness of 90 % have been done in the infiltration column apparatus. Compared to oven-dry method, the relative error of gravimetric water content measured by the TDR probe is less than 10 %, so as to indicate the feasibility and accuracy of measuring water content of coarse-grained particles using this probe.

关 键 词：TDR 探头 含水量 粗颗粒填料 高速铁路路基 

分 类 号：TU41[建筑科学—岩土工程]