抗压长支盘桩极限承载力的Sloboda模型预测

Prediction of ultimate bearing capacity of long DX piles under compressive load based on Sloboda model

采用数学模型的拟合方法，选用生物领域的Sloboda生长曲线模型，对支盘桩的桩顶荷载-桩顸沉降曲线（Q—S曲线）进行了优化的拟合分析，并对其承载力进行了预测。对9根桩的实测资料的拟合表明：Sloboda模型对支盘桩的桩顶荷载-桩顶沉降曲线有很高的拟合精度，相关系数为0．99649～0．99968，平均值为0．99878；该模型拟合效果比双曲线模型好，特别是在曲线的尾部；基于该模型的桩顶荷载的预测值与实测值的相对误差绝对值的平均值为3．93749％，所有桩拟合曲线尾部3点预测值与实测值的相对误差绝对值的平均值为1．29531％。结果表明，Sloboda模型对桩顶荷载一桩顶沉降曲线的拟合精度较高，拟合方程式能对支盘桩承载力进行预测。

Using the fitting method of mathematical model and selecting Sloboda growth curve model, the fitting analysis of load-settlement curves and the prediction of vertical ultimate beating capacity of long DX piles were carried out. The fitting results of 9 field measurement data with the model show that the fitting precision is high, the correlativity coefficients is from 0. 996 49 to 0. 999 68, the average value is 0. 998 78. The fitting effect with the model is better than the hyperbolic model. The error between prediction value and actual measurement value is 3. 937 49% , and especially, is 1. 295 31% in the tail of fitting curves. The results show that the Sloboda mathematical model have better precision for fitting of load-settlement curves, and corresponding fitting equations can be used to forecast beating capacity of DX piles.