拟合法在基桩静载试验数据分析中的应用研究

Research on application of fitting method in data analysis of pile static load test

依托豫北地区省道304濮阳白堽黄河公路大桥及接线工程单桩竖向静载试验成果,在超长大直径基桩承载力检测中采用专利技术拉压锚法将传统压力传递转换为钢绞线的拉力传递荷载。由静载试验数据得到,29000 kN加载时沉降曲率增大,桩端阻力占比14%,表现出明显的摩擦桩性状,随桩顶荷载增加桩侧摩阻力发挥规律逐渐体现为上中下三部分。在桩身轴力及桩侧摩阻力计算中运用拟合法建立桩身本构关系方程式,拟合曲线近似线性,可利用度较高,以期为同行业者提供有益思考。

Based on the results of vertical static load test of single pile of 304 Puyang Baigang Yellow River Highway Bridge and connection project in northern Henan Province,the traditional pressure transfer is converted into the tension transfer load of steel strand by using the patented tension-compression anchor method in the bearing capacity test of super long and large diameter pile.According to the static load test data,the settlement curvature increases when the 29000 kN load is loaded,and the pile end resistance accounts for 14%,showing obvious friction pile characteristics.With the increase of pile top load,the law of pile side friction resistance is gradually reflected in the upper,middle and lower parts.Uses the fitting method to establish the constitutive relation equation of pile body in the calculation of axial force of pile body and side friction resistance of pile body.The fitting curve is approximately linear and the availability is high,so as to provide useful thinking for the same industry.