【作者】 姚同斌；

【导师】 白晓红；

【作者基本信息】 太原理工大学 ， 岩土工程， 2004， 硕士

【摘要】 目前工程界普遍采用的高层建筑设计方法是把上部结构、基础和地基隔离开来分别考虑。对于桩基础则假定建筑物荷载全部由桩支撑，再按照规范提供的经验公式或在桩的静载荷试验基础上定出的单桩承载力，计算出桩数。桩位布置时兼顾建筑物荷载分布的不均匀性作适当调整，以便使每根桩的承载力得到充分发挥。此外，桩基础的计算一般不考虑桩间土和承台(或基础板)的荷载分担作用。这种方法由于忽视桩-土-承台(或基础板)的共同作用，与实际情况不相符合，其结果往往造成设计过于保守，造成很大的浪费。随着桩基础的计算分析近年来的发展，许多工程技术人员和学者力图找出更为科学有效的设计方法以取代现有的，传统的桩基础设计方法。而合理可行的桩基础设计方法又依赖于对桩-土-承台(或基础板)共同作用问题的全面了解，特别是对桩-土-承台(或基础板)共同作用机理的认识。 某电厂工程拟建新机组。根据初步设计，主厂房采用天然 太原理工大学硕士研究生学位论文地基难以实现。鉴于这样的情况，该工程选用钢筋混凝土预制方桩，为柱一桩式群桩基础。为了节约工程造价和向设计提供可靠的设计参数，揭示承台与桩、土的协同工作机理和获得桩基设计的技术与经济分析资料，同时也为今后工程桩的优化设计和施工提供依据，进行了现场群桩测试，本论文结合此次现场原位实测研究及理论分析，探讨了高层建筑承台一桩一土共同作用的机理，通过对承台下土反力的测试以及对其分析，得出桩一承台基础的承台底土反力沿轴线呈马鞍形分布的规律，通过对测试结果的分析并运用回归分析总结出此场地桩承台荷载分担比的数学公式。同时通过对桩身应力的测试分析，阐述了群桩中桩的荷载传递规律。通过对桩顶荷载的测试分析得出群桩中角桩受荷最大、边桩次之、内桩最小的结果。结合桩顶、桩侧、承台下土反力的测试数据，综合讨论了群桩、承台、土共同工作的一些原理。最后选用考虑共同作用的群桩沉降计算方法进行桩基的沉降计算，并与规范所推荐的群桩沉降计算方法进行比较，从沉降的角度对桩一土一承台的共同作用进行了讨论。更多还原

【Abstract】 Presently the designing method adopted popularly in engineering field for tall buildings is to calculate the superstruc -ture, foundation and soil separately. For pile-group foundation, designers often assume that the building loads all supported by pile stakes, they reckon the number of the pile stakes according to experienced formula which specification afforded or single pile stake bearing capacity based on experimental of dead load. The furnish of pile is adjusted accounted through characteristic of inequable of construct load in order that every pile stake play a fully role in. Furthermore, the calculation of pile group foundation doesn’t take undertaking of cap and soil between the pile stake into account. This segregation cannot conform to the reality and it could make the designing plan wasted. With the development of modelabout calculation of pile group foundation, researcher try to find thenew design method to replace the conventional design method. But the advisable design method is based on understand -ing about mechanism of the interaction among the pile and the cap & the soil. In coordination with the tests on site and analysis of theory, the essay sets forth the mechanism of the interaction among the pile and the cap & the soil of tall buildings. The distribution rule of the force between cap and soil in pile-cap foundation is saddle shape along its axis. A empirical formula estimating the proportion of load carried by piles and cap in this area is presented. Furthermore, through tests of axis force of pile, the rule of load transference of pile is summarized. Eventually the interaction among pile and soil and cap is analyzed by contrasting different manner of settlement.更多还原