考虑毛细水负压力引起坑外场地沉降量计算方法和潜在威胁性研究  

Calculation Method and Potential Threat of Settlement Outside Foundation Pit Considering Negative Pressure of Capillary Water

作　　者：周爱兆[1] 胡远 隋晓岚 ZHOU Ai-zhao;HU Yuan;SUI Xiao-lan(School of Civil and Architecture Engineering,Jiangsu University of Science and Technology,Zhenjiang 212003,China)

机构地区：[1]江苏科技大学土木工程与建筑学院,镇江212003

出　　处：《科学技术与工程》2020年第2期779-784,共6页Science Technology and Engineering

基　　金：国家自然科学基金(51579119);镇江市重点研发计划(社会发展)项目(SH2018024)。

摘　　要：为得出毛细水负压力对坑外场地土体沉降影响,从而更准确计算出因坑内水位降深引起的坑外土体沉降量。借用海森(Hazen A)经验公式进行估算水位下降后毛细水上升高度,进一步得出毛细作用产生的负压力。在规范给出的分层总和法计算土体沉降基础上,给出考虑毛细水负压力计算土体沉降方法,为计算坑内降水造成周边土体沉降提供参考。通过该计算方法分别分析在不同孔隙比、有效粒径条件下,毛细水负压力对土体沉降的影响性。结果表明毛细水上升高度随着土体粒径及孔隙比的减小而增大,尤其当土体有效粒径小于0.075 mm时,应着重考虑考虑毛细水负压对土体沉降影响。Based on the empirical formula of A.Hazen,the rising height of capillary water after water drawdowns was estimated,and then the negative pressure produced by capillary water was calculated.Using the layered summation method given in the China’s national code,a method was developed to determine the ground soil settlement considering negative capillary water pressure.The new method was applied to calculate the soil settlement of a pit site.Different pore ratios were tested ineffective diameter,and the impact of negative pressure of capillary water on soil settlement was analyzed.Results show that the elevation of capillary water increase with the decrease of soil effective diameter and the void ratio,especially when effective diameter of soil is less than 0.075 mm,the impact of capillary water negative pressure on soil settlement should be considered.

关 键 词：毛细水高度 毛细水负压 沉降 计算方法 

分 类 号：TU478[建筑科学—结构工程]