【摘要】 桩的承载力是结构安全的基础，自平衡静载试验是评估基桩承载特性的有效方法.基于多层荷载箱自平衡试桩法，提出了一种自平衡试桩桩顶荷载-沉降(Q-s)曲线等效转换方法，并通过实际工程案例，证明了该方法的科学性及准确性.结果表明：提出自平衡试桩Q-s曲线等效叠加转换方法，有效还原了顶载下基桩的轴力传递规律，考虑了桩的压缩变形，适用于基桩承载力的检测及分析；通过西宁地区某工程基桩承载力现场试验，测得等效叠加转换方法与锚桩法得出的Q-s曲线相关系数平均可达94.39%,且该方法得到的曲线比传统静载试验更完整、比常规等效转换方法更贴近实际.提出的多层荷载箱自平衡试桩Q-s曲线等效叠加转换方法可为复杂基桩承载力评估提供科学依据和参考.更多还原

【Abstract】 The bearing capacity of piles is the foundation of structural safety, and self-balancing static load tests are an effective method for evaluating bearing characteristics. This paper proposes an analytical transformation method for Q-s curves based on the self-balancing pile test method with multiple load cells, and demonstrates the scientific validity and accuracy of the method through actual engineering cases. The results show that the equivalent superposition transformation method of Q-s curve of self-balanced test pile proposed in this paper effectively restores the axial force transfer law of foundation pile under top load, considers the compression deformation of pile, and is suitable for the detection and analysis of bearing capacity of foundation pile. Through the field test of pile bearing capacity of a project in Xining area, the correlation coefficient of Q-s curve obtained by the equivalent superposition conversion method and the anchor pile method can reach 94.39 % on average, and the curve obtained by this method is more complete than the traditional static load test and closer to reality than the conventional equivalent conversion method. The multi-layer load cell self-balancing pile test Q-s curve equivalent superposition transformation method proposed in this study can provide a scientific basis and reference for the assessment of complex foundation pile bearing capacity.更多还原