摘要
现有计算方法在确定基坑支护结构上的水土压力时,大多简单地将支护结构两侧的水压力视为静水压而忽略地下水渗流的影响。针对这一问题,基于稳态渗流理论,以表现为强渗透性的土层为研究对象,采用简化的Laplace方程推导了任意土层任意点深度的孔隙水压分布表达式,结合Rankie土压力理论提出了考虑渗流作用的水土压力计算新方法。通过两个实例的计算结果表明:相较于水土合算和水土分算法,由于地下水渗流作用的影响,作用于支护结构上的主动土压力增大,被动土压力减小。同时主动区的孔隙水压显著下降,被动区孔隙水压有所增大。该方法与采用流网法的计算结果基本一致,且更简便实用。
The water pressure acting on both sides of the supporting structure of deep foundation excavation is simply regarded as hydrostatic pressure when the water-earth pressure is computed by using the present calculation methods,in which the effects of groundwater seepage are mostly ignored.For the issue,a new calculation method was proposed.Firstly,the soil layers with strong penetrability were assumed as research subject.Then a simplified Laplace equation was adopted to calculate the distribution of pore pressure in arbitraty depth of arbitrary soil layer based on steady seepage theory.At last,the water-earth pressure could be obtained by combining Rankine earth pressure theory.Compared to conventional methods（estimating water and earth pressures separately or together）,the results showed that the active earth pressure on supporting structure increased and passive earth pressure decreased due to seepage force.And the pore pressure decreased significantly in active zone and had a litter increase in passive zone.Meanwhile,the results obtained from the suggested method agreed with the one compated by flow-net method.The proposed method was more convenient and practical.
出处
《工业建筑》
CSCD
北大核心
2017年第12期121-126,共6页
Industrial Construction
基金
福建省自然科学基金项目(2017J05061)
福州大学青年教师科研启动基金项目(XRC-1531)
关键词
基坑
水土压力
稳态渗流
任意土层
deep foundation excavation
water-earth pressure
steady seepage
arbitrary soil layer
