沉井下沉侧壁摩阻力离心模型试验研究

沉井下沉过程中侧壁摩阻力的大小及分布是影响沉井能否顺利下沉的因素之一,为了更好地研究其特性,以沪通长江大桥主墩沉井基础为研究对象,基于离心模型试验对4组不同埋深情况下沉井下沉过程进行研究。结果表明:在一定的下沉深度范围内,沉井侧壁摩阻力随下沉深度的增加呈先增大后减小的趋势,且当入土深度为2/3倍沉井埋深时,沉井侧壁摩阻力达到极大值。在此基础上以分段函数的形式建立了沉井下沉侧壁摩阻力的计算模型,所得结论可为类似工程提供参考。

Study on Side-wall Frictional Resistance During Open Caisson Sinking by Centrifugal Model Test

The size and distribution of side wall frictional resistance during open caisson sinking is one of the factors that affect the successful sinking of open caisson.To better study its characteristics the open caisson foundation of the main pier of Shanghai-Nantong Yangtze River Bridge was taken as the research object.Based on centrifugal model test study on the sinking process of open caisson in 4 different buried depths was carried out.The results show that in a certain range of sinking depth the side wall frictional resistance of open caisson increases first and then decreases with the increase of sinking depth and when the sinking depth is 2/3 times the buried depth of open caisson the side wall frictional resistance of open caisson reaches extreme value.On this basis a calculation model of side wall frictional resistance during open caisson sinking was established in the form of a piecewise function.The conclusions obtained can be used as a reference for similar projects.