大型沉井实测下沉阻力分析

大型沉井下沉过程中摩阻力和底部的端阻力分布是沉井下沉可行性的主要控制因素，基于大直径桩和中、小型沉井的研究成果已不适用。结合马鞍山长江公路大桥南锚碇大型沉井下沉过程的实时监测数据，分析了大型沉井基础下沉机理和下沉过程中的受力特性，验证了不同地基极限承载力公式在沉井工程中的适用性;对比沉井下沉至不同深度时，底面阻力和井壁侧摩阻力的大小及分布规律，对现行规范建议的侧摩阻力的计算公式和分布特征进行初步修正，结论可供大型沉井工程借鉴和参考。

Analysis of Large Caisson Sinking Measured Resistance

In the sinking process of large-scale caisson, the distribution of the shaft friction and the end resistance is the main controlling factor of the sinking feasibility, but the research based on large-diameter piles and small or medium-scale caissons are no longer applicable. With the real-time monitoring data of the south anchorage caisson sinking process of Yangtze River Highway Bridge in Ma An Shan, this paper analyses the underlying principles and the mechanical characteristics in the sinking process of the large-scale caisson foundation, Verify the applicability of different formulas of the foundation ultimate bearing capacity in the of the caisson; Contrast sink to different depths , the value and the distribution rules of the shaft friction and the end resistance, this paper also modifies the formulas and distribution characteristics of the shaft friction proposed by current specifications, and the conclusions are suitable for reference of similar scale projects.