抗滑桩桩后土拱形状及影响因素

为描述抗滑桩桩后土拱的形状,采用平面应变有限元模型,通过搜索数值计算结果中最大主压应力迹线,拟合土拱轴线的描述方程,分析桩间距、土体参数、桩土界面参数、桩后荷载等因素对拱高和拱跨的影响规律,提出考虑上述因素的土拱轴线形状方程.结果表明:桩间距和桩后土压力大小对土拱形状影响最大.土拱跨高比与桩间距呈二次正相关关系,在桩间距为4.46倍桩直径时,土拱受力最为有利.随着桩后土压力增加,土拱拱高呈陡降形对数函数变化规律,反映了土拱从形成-发展-破坏的演变规律.

Shape of soil arch behind anti-slide piles and its major influence factors

In order to describe the shape of soil arch behind anti-slide piles,numerical simulations were carried out based on plane stain FEA models.Maximum principal compressive stress traces were investigated based on the calculated results and arch axis equations were set up by fitting analysis.The influences of major factors such as pile space,soil and pile-soil interface parameters,load magnitude on the arch shape were analyzed,and the equation with consideration of aforementioned factors was finally obtained.The results show that pile space and the magnitude of pressure on piles are the most notable factors affecting the arch shape.Ratio of span to rise of arch has a quadratic correlation with pile space.Arch effect will bring soil strength into full use as the pile space is 4.46 times of diameter.Arch rise drops as a steep dropping logarithmic function curve with the increase of pressure,which reflects the evolutionary process of arch effect from formation to development and destruction.