摘要
毛细屏障(CB)导流长度是评估边坡加固效果的关键。先前对于导流长度的推导以二层覆土结构为基础,而地质调查工程中发现,上部土层厚度影响显著,计算缺乏适用性评估。本次研究在二层结构试验基础上改变上部土层厚度,并针对三层覆土结构的降雨入渗进行分析,阐明了二、三层CB导流长度近似方程的应用。研究结果表明:(1)二层结构中,与经典分析不一样的是,当上部土层厚度小于30 cm时,试验导流长度极限值小于计算值,而上部为微细砂时,计算值至少需要考虑一个空气渗透值的厚度;(2)三层CB结构试验中,含有细砂上部适用厚度为30~50 cm,80%的渗透率对于解析解的适用性最佳。一系列大型土槽试验具体指出极限长度预测公式的适用范围,大大提高了计算结果的适用性及准确性,可为边坡加固的评估提供更精准的预测。
The capillary barrier(CB)diversion length is critical in assessing the effectiveness of slope stabilization.The previous derivation of the diversion length was based on a two-layer overburden structure.While researchers found that the thickness of the upper soil layer has a significant effect on the stability,and the calculation lacks applicability assessment during the geological investigation.In this study,the application of the approximate equations for the length of CB diversion length in the two-layer and three-layer is clarified by varying the thickness of the upper soil layer on the basis of the test of the two-layer structure and analyzing the rainfall infiltration for the three-layer overburden structure.The results of the study show that(1)in the two-layer structure,unlike in the classical analysis,the limit value of the experimental infiltration length is smaller than the calculated value when the thickness of the upper soil layer is less than 30 cm,whereas the calculated value needs to take into account at least one air infiltration value of the thickness of the upper part,when the upper part is a microfine sand;(2)In the test of three-layer CB structure,the applicable thickness of the upper part containing fine sand is 30-50 cm,and 80%permeability is the best applicable for resolved solution.In this study,a series of large-scale soil trench tests specifically point out the scope of application of the limit length prediction formula,which greatly improves the applicability and accuracy of the calculation results,and can provide more accurate predictions for the assessment of slope stabilization.
作者
赵志鹏
景明
黄亚军
吕志强
ZHAO Zhipeng;JING Ming;HUANG Yajun;LYU Zhiqiang(Lanzhou College of Information Science and Technology,Lanzhou 730300,Gansu,China;China Construction Civil Engineering Co.,Ltd.,Beijing,100070,China;First Engineering Co.,Ltd.,affiliated to CCCC First Highway Engineering Group,Beijing 102205,China)
出处
《矿产勘查》
2023年第9期1722-1730,共9页
Mineral Exploration
基金
2023年甘肃省高等教育教学成果培育项目“新工科背景下土木工程专业应用型创新人才培养与探索实践”(192)资助。
关键词
地质调查工程
毛细屏障
导流长度
模型试验
geological survey engineering
capillary barrier
inflow length
model test
