摘要
为研究湿陷性Q_(2)黄土场地建筑地基在降雨入渗影响下的沉降变形规律,首先通过压力板试验和直剪试验研究了Q_(2)黄土的水力—力学特性,拟合了黄土的非饱和渗流参数和随含水量变化的力学参数表达式;其次,基于试验结果提出了一种考虑土体湿陷性的地基沉降数值模拟方法,并以西安某Q_(2)黄土场地上临近雨水入渗点的建筑地基为依托,分析了降雨入渗下的建筑地基的沉降变形特征。结果表明Q_(2)黄土具有显著的湿陷性,粘聚力、内摩擦角、变形模量随含水量的增加而近似线性劣化,文中提出的数值模拟方法可以较好地模拟出Q_(2)黄土的这一特性;Q_(2)黄土场地建筑地基在雨水入渗工况下,考虑地基土体湿陷性的沉降变形分析结果相对于不考虑湿陷性的分析结果而言,地基沉降变形最大可增加2倍左右,考虑湿陷性的地基沉降分析结果更符合工程实际。
The settlement deformation law of building foundation in collapsible Q_(2) loess site under the influence of rainfall infiltration is studied.The hydraulic-mechanical properties of Q_(2) loess are studied through the pressure plate test and direct shear test,and the unsaturated seepage parameters of loess and the expressions of mechanical parameters with water content are fitted based on the test results.A numerical simulation method of foundation settlement considering collapsibility is proposed,and the settlement of the building foundation under rainfall infiltration is analyzed based on a building foundation near the rainwater infiltration point on a Q_(2) loess site in Xi'an.The results show that Q_(2) loess has significant collapsibility,which is mainly manifested in the approximate linear deterioration of cohesion,internal friction angle,and deformation modulus with the increase of water content.The proposed numerical simulation method can greatly simulate the characteristics of Q_(2) loess.Under the condition of rainwater infiltration,the analysis results of foundation settlement considering collapsibility of soil can increase about 2 times compared with the analysis results without considering collapsibility.The analysis results of foundation settlement considering collapsibility are more in line with the engineering practice than other methods.
作者
任哲庆
REN Zheqing(Chinese Flight Test Establishment,Xi'an 710089,China;School of Architecture and Civil Engineering,Xi'an University of Science and Technology,Xi'an 710048,China)
出处
《低温建筑技术》
2023年第1期132-137,共6页
Low Temperature Architecture Technology
关键词
Q_(2)黄土
湿陷性
降雨入渗
建筑地基
力学参数劣化
Q_(2)loess
collapsibility
rainfall infiltration
building foundation
mechanical parameter deterioration
