【作者】 于秀娟；

【导师】 张彬； 景海河；

【作者基本信息】 辽宁工程技术大学 ， 岩土工程， 2006， 硕士

【摘要】 在桩基础的设计体系中,解决承载力是一个关键性问题。而沉降特性是确定承载力的重要指标,单桩沉降方面的理论分析方法主要有荷载传递法、弹性理论法、剪切变形传递法、数值分析法、其它经验简化法等五个方面。理论分析方法不如现场原型试验直观和准确,但具有经济、快捷、预测、定量对比的优势,其中荷载传递法是利用桩荷载试验资料进行分析、确定荷载传递函数,依靠其数据运算得到荷载--沉降曲线,由此分析桩的工程力学性能。本文结合我国目前工程实践和现行规范规定,从浙江兰溪市某典型静荷载实例出发,在深入分析竖向荷载作用下单桩的荷载传递过程、变化规律和荷载-沉降特性之后,依据不同土层呈现出不同应力应变关系,应用桩的侧摩阻力和沉降位移的改进荷载传递模型,计算桩顶沉降分别处于弹性、弹塑性或塑性等不同状态时所对应的桩顶荷载值,推导出桩顶沉降与承载力之间的一系列公式,用以模拟桩--土相互作用机理,从而实现以桩顶沉降量来控制桩的承载力的设想。利用本文工作方法,只需土的一般物理力学性能指标即可建立实用性较强的荷载传递函数,进而估算单桩的Q-S曲线。当缺乏某地的静荷载试验资料时,利用该法可了解桩基的沉降特性;或在静荷载试验之前预估试桩的极限承载力和加载等级时,可以提供有效的帮助,具有较好的实践价值。更多还原

【Abstract】 To resolve bearing capacity is the key problem in the pile foundation design system. But the sedimentation property is the important index to confirm the bearing capacity, primary theory analysis methods of single pile are: load transfer approach, elastic theory method, shearing deformation transfer approach, numerical analysis method and other experiential simplified methods i.e. The theory analysis is not intuitionistic and exact than in-situ test, but it is superior to in-situ test in economic, quick, predictable, quantified. To load transfer approach,it is analysised and confirmde the load transfer function through pile load test profile and through the function to get load-sedimentation curve, so to analysis the engineering properties of the pile.The paper combine our country engineering practice recently and the criterion rules now, beginning from the classic static load instance in lanxi city of zhejiang province, after deeply analysis the load transfer process ,transformation disciplinarian and load-sedimentation properties of the single pile on the vertical load, by the deferent stress-strain relationship presented by the deferent soil strata, applied modified load transfer model of the side friction resistance and sedimentation displacement. Using modified model to calculate the corresponding pile top load quantity when it is in the elastic, elastic-plastic or plastic situation, derive a series formula between the pile top sedimentation and the bearing capacity, using it to simulate the interaction between the pile and soil, thereby to realize the dream to control the pile load bearing by the pile top sedimentation quantity.Through the theory of the work, the soil average physical mechanic properties is only needed to construct practical load transfer function, further to estimate the Q-S curve of single pile. when the static load test profile in certain place ,using this method to know the sedimentation properties of the pile foundation; or while pro-estimate the limited bearing capacity and load grade before the static test ,it may provide effective help and practice value is better.更多还原