桩-土承载性能剪切流变分析新理论

NEW THEORY FOR SHEAR RHEOLOGICAL ANALYSIS OF PILE′S BEARING PERFORMANCE

充分考虑岩土力学性质的时间相关性,研究土的流变特性及桩-土的空间效应问题及复杂地质条件下桩-土和土-土相互作用的时间效应和空间效应对承载性能的影响机制。将土的流变学理论应用于桩基础工程中,建立一套完善、实用的桩-土体系时空效应模型,并对多种桩型、桩径及不同受力特点单桩的桩-土相互作用机制随时间的变化效应进行分析研究。提出一套桩-土承载性能时空效应剪切流变分析的新理论,并推导出单桩承载性能时空效应理论的闭合解析解和半解析解。结合试验研究进行验证。该理论可用于指导桩基础设计时预估承载力的变化趋势,有效地控制基础沉降;同时用于桩基础施工质量的验收,计算基础的荷载-沉降关系,弥补目前桩基础检测技术的不足。

This paper presents theoretical as well as experimental results on the bearing performances of the pile-soil system. To sufficiently consider the time effect of geomaterials and the spatial effect of the pile-soil system on pile′s bearing performance,a rheological theory of soil for the pile foundation is proposed. Based on the rheological theory,an improved analytical model of pile-soil system is established to analyze the mechanism of spatiotemporal effect on the pile′s bearing capacity. Some analytical and semi-analytical solutions of the time and spatial effects of single pile′s bearing performance are obtained. This new theory can be used to predict various behaviors of pile foundations,such as the controlling of foundation settlement. In addition,the theory can also be used to validate the construction quality of foundation and to compute the load-displacement relationship of pile,which can supplement the current foundation test technique.