全吸力范围内土-水特征曲线的快速测定方法  

A rapid method for determining the soil-water characteristic curves in the full suction range

作　　者：李旭[1] 刘阿强 刘丽[1] 刘艳[1] 吴永康 LI Xu;LIU A-qiang;LIU Li;LIU Yan;WU Yong-kang(Key Laboratory of Urban Underground Engineering of Ministry of Education,Beijing Jiaotong University,Beijing 100044,China)

机构地区：[1]北京交通大学城市地下工程教育部重点实验室,北京100044

出　　处：《岩土力学》2022年第2期299-306,共8页Rock and Soil Mechanics

基　　金：国家自然科学基金(No.51979002);北京市自然科学基金(No.8192034)。

摘　　要：传统的宽(全)吸力范围内的土-水特征曲线(SWCC)测量方法动辄耗时数月。为了更好地使非饱和土力学理论指导工程实践,SWCC的快速测定显得尤为关键。为开发宽(全)吸力范围内SWCC的快速测定方法,联合压力板法、并行滤纸法、露点水势仪法进行了两种不同土体的宽吸力范围内SWCC的测定试验。试验结果表明:(1)并行滤纸法与串行滤纸法的试验结果能较好地吻合,故可采用并行滤纸法代替串行滤纸法以缩短测量时间;(2)当测量的试验数据满足SWCC的大致形状时(或满足工程设计需求时),可适当减少试验数量,以提高测定效率,联合测定方法测量一条完整的SWCC仅需要10~12个点即可完成;(3)联合测定方法可将SWCC测量时间由数月缩短至7~10d。所提出的联合测定方法实现了宽(全)吸力范围内SWCC的快速、精准测定,有望使得SWCC的测量成为常规的土工试验。The traditional methods for determining the soil-water characteristic curve(SWCC) in the full suction range always takes several months. To better guide the engineering practice with the theory of unsaturated soil mechanics, the rapid determination of SWCC is particularly important. In this study, a rapid measurement method for SWCC in the wide(full) suction range was developed with the combination of pressure plate method, parallel filter paper method and dew point water potential meter method, and the proposed method was used to test two different soils. Results showed that: i) The experimental data of the parallel filter paper method and that of the serial filter paper method were in good agreement, so the parallel filter paper method can be used instead of the serial filter paper method to shorten the measurement time. ii) When the measured data meet the general shape of SWCC(or meet the requirements of engineering design), the number of tests can be reduced appropriately to improve the measurement efficiency. A complete SWCC can be determined by the proposed combined method with only 10 to 12 points. iii) The measurement method proposed in this study can shorten the measurement time of SWCC testing from several months to 7–10 days. The combined method proposed in this study achieved the rapid and accurate determination of SWCC in wide(full) suction ranges, which is expected to make the SWCC measurement become a routine geotechnical test.

关 键 词：快速测定 土-水特征曲线 压力板法 并行滤纸法 露点水势仪 

分 类 号：TU431[建筑科学—岩土工程]