【摘要】：剛性樁復合地基因其在處理軟土地區(qū)能夠較好地控制沉降變形,其能夠很好地穿過不良地基,對提高路基的承載能力和控制道路的工后沉降都起到了很好的工程經(jīng)濟效益。又因剛性樁復合地基大量運用于工程之中,在工程的施工過程中,以及工程投入運營和使用后,收集到了大量關于剛性樁復合地基的工程數(shù)據(jù),不斷地改進其設計,使得剛性樁復合地基的工程技術、理論得到了快速地進步,也推動剛性樁復合地基向著更成熟化的方向發(fā)展；與此同時也產(chǎn)生了許多新型樁形,其中現(xiàn)澆X形混凝土樁技術就是由河海大學開發(fā)的具有自主知識產(chǎn)權的新型專利技術。本文在相關研究現(xiàn)狀的基礎上,建立單樁復合地基計算模型,通過考慮現(xiàn)澆X形樁側凹弧段土拱效應,令凹弧段側摩阻力與凸出段側摩阻力比值為m,并對不同土層的土體參數(shù)對m影響進行了分析,并將現(xiàn)有的圓形樁側摩阻力計算公式進行推廣應用得到了現(xiàn)澆X形樁側摩阻力計算公式。同時借助大型有限元分析軟件ABAQUS建立有限元單樁復合地基模型,并針對不同的工況條件下建立數(shù)值模擬分析模型,比較現(xiàn)澆X形單樁復合地基與圓形單樁復合地基的異同。 本文開展的主要工作包括以下幾個方面： 1、通過閱讀現(xiàn)有有關圓形剛性樁復合地基相關文獻,得出普通樁型的一般規(guī)律；結合對X形樁凹弧段土拱效應分析,得出樁凸出段與凹弧段側摩阻力沿樁周同一深度處的分布規(guī)律； 2、利用(1)中分布規(guī)律,結合現(xiàn)有樁側摩阻力計算方法-荷載傳遞法,通過以能量法建立平衡方程,求解出均質地基土中X形單樁側摩阻力沿樁身分布規(guī)律； 3、運用與均質地基土相同計算方法,計算多層地基土中X形單樁側摩阻力沿樁身分布規(guī)律,并與實際工程測量數(shù)據(jù)進行對比分析； 4、利用有限元分析軟件ABAQUS建立X形單樁復合地基計算模型及圓形單樁復合地基模型,對兩種樁型復合地基在相同的工況條件下,改變褥墊層變形模量、厚度、樁身模量以及樁端土體變形模量的大小,分別對比分析以上各種工況下兩種單樁復合地基承載特點、沉降、樁身軸力與樁側摩阻力的變化規(guī)律； 5、通過數(shù)值分析軟件結合現(xiàn)澆x形樁復合地基分析修正劍橋模型中主要參數(shù)變化對復合地基計算結果的影響進行了分析討論,為今后類似的工程在使用修正劍橋模型選取計算參數(shù)時提供參考借鑒。
[Abstract]:The rigid pile composite soil gene can control the settlement and deformation in the soft soil area, and it can well pass through the bad foundation, which can improve the bearing capacity of the roadbed and control the post-construction settlement of the road. Because rigid pile composite foundation is widely used in engineering, in the process of construction, and after the project is put into operation and use, a large amount of engineering data about rigid pile composite foundation are collected, and its design is continuously improved. The engineering technology of rigid pile composite foundation has made rapid progress in theory, and has also promoted the development of rigid pile composite foundation towards a more mature direction. At the same time, many new types of pile have been produced. The cast-in-place X-shaped concrete pile technology is a new patent technology with independent intellectual property developed by Hehai University. In this paper, based on the related research status, the calculation model of single pile composite foundation is established, and the soil arch effect of side concave arc section of cast-in-place X pile is considered. The ratio of the side friction of the concave arc segment to the side friction resistance of the protruding section is m, and the influence of soil parameters of different soil layers on m is analyzed. The formulas for calculating the lateral friction of cast-in-place X-shaped piles are obtained by popularizing the existing formulas for calculating the lateral friction of circular piles. At the same time, the finite element model of single pile composite foundation is established with the help of the large finite element analysis software ABAQUS, and the numerical simulation analysis model under different working conditions is established to compare the similarities and differences between cast-in-situ single pile composite foundation and circular single pile composite foundation. The main work of this paper includes the following aspects: 1. By reading the existing literature on circular rigid pile composite foundation, the general rule of common pile type is obtained, and the soil arch effect of X shaped pile concave arc section is analyzed. The distribution law of lateral friction of protruded pile and concave arc along the same depth around the pile is obtained. 2. By using the distribution law of (1), combined with the load transfer method, the equilibrium equation is established by energy method. The distribution law of lateral friction of X shape single pile along the pile body in homogeneous foundation soil is solved. 3, the same calculation method as that of homogeneous foundation soil is used to calculate the distribution law of side friction of X shape single pile along pile body in multi layer foundation soil. And compared with the actual engineering survey data. 4, using the finite element analysis software ABAQUS to establish the X shape single pile composite foundation calculation model and circular single pile composite foundation model, Under the same working conditions, the bearing characteristics of two kinds of pile-type composite foundation are compared and analyzed by changing the deformation modulus, thickness, pile body modulus and pile end soil deformation modulus of the two kinds of pile composite foundation under the same working conditions. Settlement, axial force of pile body and friction on the side of pile; 5. The influence of the main parameters of Cambridge model on the calculation results of composite foundation is analyzed and discussed by using numerical analysis software combined with cast-in-place x-shaped pile composite foundation analysis. It provides a reference for similar projects in the future when selecting calculation parameters using the modified Cambridge model.
【學位授予單位】：廣東工業(yè)大學
【學位級別】：碩士
【學位授予年份】：2014
【分類號】：TU470

【引證文獻】

相關碩士學位論文 前1條

1 屈江龍;樁承式加筋路堤承載性狀研究[D];廣東工業(yè)大學;2015年

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本文編號：2183444