长螺旋钻孔压灌混凝土灌注桩极限侧阻力和端阻力取值模拟分析

摘要

长螺旋钻孔压灌桩单桩竖向极限承载力的确定依据现行规范计算值和现场实际检测值往往相差较大，通过 FLAC3D 软件模拟，建立了摩尔－库仑弹塑性实体模型，模拟了桩逐级加载情况下承载力和位移变化，并结合已完成桩承载力检测数据分析其实际情况。在该文分析过程中，灌注桩采用24 m、25 m 和26 m 三种长度，最大加载荷载值为8800 kN，根据数据模拟和实际检测数据分析得出，山西地区依据相关规范经验参数法，采取泥浆护壁钻（冲）孔工艺确定长螺旋灌注桩极限承载力时，取桩极限侧阻力和端阻力值相对安全。%The screw drilled pile vertical ultimate bearing capacity value calculated according to the current specifications and actual values frequently is quite different.In this paper we analyzed the process through FLAC3D software simulation, established Moore-Coulomb elastoplastic solid model to simulate the displacement of pile bearing capacity and gradual load-ing conditions,and combined with the completed pile bearing capacity test data to analyze the actual situation.In this pa-per,the changes were analyzed when using the piles 24 meters,25 meters,26 meters and maximum load value load 8 800 kN,according to the data analysis and simulation of the actual test data obtained,Shanxi Province based on related specifi-cations empirical method to determine parameters of long spiral pile ultimate bearing capacity was relatively safe when slurry wall drilling (wash)bore process took pile ultimate resistance and end resistance value.