【作者】 袁洪升；

【导师】 史三元；

【作者基本信息】 河北工程大学 ， 结构工程， 2009， 硕士

【摘要】 随着社会经济的快速发展,现代建筑的发展也呈现出新的特点,表现为层数增多、体型庞大、受力复杂等,这种情况下首先要解决的就是建筑物的土力学与地基基础问题,碎石与CFG两桩型复合地基在这种趋势下得到了发展和应用。本文通过理论计算、数值模拟和工程实例的方法对该形式复合地基进行了研究并得出以下结论:(1)对碎石与CFG两桩型复合地基的产生和发展进行了分析归纳。虽然碎石与CFG两桩型复合地基具有材料环保、施工方便和经济性好等方面的优势,但其理论发展与工程应用还很不够,有待于深入研究。(2)在总结前人研究成果的基础上详细阐述了碎石与CFG桩的受力机理及其承载力和沉降的计算方法,给出了适合于工程使用的计算公式;(3)通过ANSYS分析程序,利用三维有限元法对两桩型复合地基进行了对比分析,对比分析了多种方案下桩身应力和土体附加应力分布,并探讨了垫层的模量和厚度对承台沉降的影响和对应力的调节作用。(4)结合北京地区某工程将理论运用于工程实践中,从地基处理方案的选择、复合地基的设计与计算、施工中主要控制内容到施工完毕后的地基检测,步步深入的对两桩型复合地基的实用性进行了论证,实例分析表明:碎石与CFG两桩型复合地基能够大幅提高天然地基的承载力并控制地基变形,能够很好的消除地基液化,是一种经济实用的地基处理方法。本文通过研究证实了碎石与CFG两桩型复合地基的可靠性,对其理论的深入研究具有推广工程应用方面的参考价值。更多还原

【Abstract】 With the rapid development of society and economy,modern architecture presents some new features,for higher layer,large,complex loading,etc. In this case,the first problem to solve is foundation of stress. Gravel and CFG pile composite foundation become a trend in foundation treatment.Firstly,a brief review was given on the emergence and development of gravel and CFG pile composite foundation. And compared to pile foundation,it is of economic and environmental protection,practicality,due to the stress principle, material selection,construction methods etc.Secondly,on the basis of predecessors’ achievements,the bearing capacity, settlement mechanism and the calculation method of Gravel and CFG pile composite foundation was showed in this paper,formulas for engineering use was presented;Thirdly, through ANSYS analysis procedures,using the three-dimensional finite element method for pile composite foundation,pile stress and soil additional stress under various solutions were presented. The impact of stress and the adjustment function of the settlement of modulus and thickness of the cushion is discussed.Finally, based on the theory, a project in Beijing will be applied as engineering practice. From selecting plans of ground treatment,the design and calculation of main contents of construction,control to testing after construction of the foundation, the theory about foundation is confirmed applicably. It draws a conclusion: Gravel and CFG pile composite foundation can greatly improve the bearing capacity and control deformation of natural foundation,can be very good to eliminate liquefied foundation. It is a kind of economical and practical treatment method.This paper through studying the gravel and CFG pile composite foundation, confirms it’s reliability. The theoretical research and application is of high reference value for the development of technology foundation.更多还原