水力发电学报2013，Vol.32Issue(1)：248-253,262,7.
分散性土的综合判别准则与针孔试验方法的改进
Comprehensive criterion of dispersive soil and improvement of pinhole test
摘要
Abstract
Surface erosion or piping failure often occurs in the earth-work constructions with dispersive soil once subject to water. The dispersivity of soil is usually identified with five methods of double-hydrometer test, pinhole test, crumb test, pore water salts test and exchangeable sodium percent test, but sometimes all these methods produce different results, making the identification practically difficult. This paper studies the dispersivity criterion and the improvement of pinhole test through a case study of the core soil in the Songta hydropower. The results indicate that comprehensive identification criteria can be calculated by assigning a suitable weight to each of the methods. The results indicate that the weight values are given to the double-hydrometer test, pinhole test, crumb test, pore water salts test and exchangeable sodium percent test, which is 20% , 20% , 40% , 10% and 10% respectively, then the total of dispersive, intermediate and non-dispersive values are calculated separately. (1) If the dispersive value exceeds 50% , the soil is dispersive; (2) If the dispersive value is 50% and the intermediate value is no less than 20% , the soil is dispersive. Otherwise, it is intermediate. (3) If the dispersive value is less than 50% and the dispersive and intermediate values are no less than 50% , the soil is intermediate. Otherwise, it is non-dispersive. This study reveals that after the pinhole test is finished, the pinhole of non-dispersive soil is not changeable, while the pinhole of dispersive soil becomes larger, but it is almost straight and trim. If the pinhole is trumpet-like and became softened, it is suggested that the pinhole wall is coated with adhesive material of 3 ～ 4 mm thick to protect its free surface and prevent wrong identification.关键词
水工材料/判别准则/试验方法/分散性土/针孔试验Key words
hydraulic material/ identification criterion/ test method/ dispersive soil/ pinhole test分类
建筑与水利引用本文复制引用
樊恒辉,赵高文,路立娜,李振..分散性土的综合判别准则与针孔试验方法的改进[J].水力发电学报,2013,32(1):248-253,262,7.基金项目
国家自然科学基金(50979094) （50979094）
"十二五"国家科技支撑计划(2011BAD31B05) （2011BAD31B05）
西北农林科技大学基本科研业务(QN2009089) （QN2009089）
