浆固碎石桩荷载传递特性试验与数值分析

Numerical Analysis and Model Tests on Axial Load Transfer of Grouted Gravel Pile

通过室内模型试验,对浆固碎石桩这一新型桩基技术的承载性状、荷载传递特性进行了探讨。试验结果显示,浆固碎石桩极限承载力明显大于桩底注浆桩和素混凝土桩的极限承载力,说明浆固碎石桩中水泥砂浆胶结桩侧泥皮和桩底沉渣改善了桩侧摩阻和端阻能力。通过对模型桩P—S关系、桩端阻力Q_p—P关系的分析,初步了解了浆固碎石桩在竖向荷载作用下的承载性状,同时给出了浆固碎石桩的端阻力及侧摩阻力的提高系数。在此基础上,利用Flac^(3D)三维有限差分软件对模型试验进行计算分析,进一步研究浆固碎石柱的承载性状,揭示了模型桩受荷后的荷载传递规律。

Grouted gravel pile is a new technique of pile,bearing behaviors and load transfer of this pile are studied in model test.The results of the model test show that bearing capacity of grouted gravel pile is higher than that of bottom grouting piles and plain concrete piles,and that grouting could increase frictional resistance and tip resistance.The bearing behaviors of model piles is preliminarily studied and strengthen coefficients of frictional resistance and tip resistance are obtained by the way to analyse curve of load vs settlement and curves of tip resistance vs load and settlement.Furthermore,Flac^（3D） is employed to analysis grouted gravel pile model test.The bearing behaviors of grouted gravel pile is further studied and regularity of load transfer of model pile under vertical load is generalized in numerical analysis.