【作者】 杨继超；

【导师】 别社安；

【作者基本信息】 天津大学 ， 水利工程， 2012， 硕士

【摘要】 作为码头三大型式之一的板桩码头,在结构强度、施工速度及工程造价等方面有较大优势。由于理论计算和建设技术的不完善,我国板桩码头多用于中小型码头的建设。为适应港口大型化、深水化的要求,板桩码头的理论计算需要对锚碇点位移及土体反力与位移的关系进一步完善。锚碇点位移对码头前沿位移和前墙内力均有较为明显的影响。为合理计算锚碇点位移及发生位移后的前墙内力,基于m法使用联合求解法对板桩结构进行计算。联合求解计算中前墙和锚碇墙简化为弹性地基梁单元,拉杆简化为杆单元,构成平面框架问题,整体求解板桩问题。计算表明,联合求解法得到的位移值和内力值均与实测数据吻合较好,能够合理反映出前墙锚碇点位移大小,相比m法得到的前墙负弯矩明显增大;对深水码头而言,拉杆变形量和锚碇位移数值相当,当开挖泥面较深时,拉杆变形量是引起锚碇点位移的主要因素。当码头发生较大位移后,墙前土体水平反力p与水平位移y的相关关系有待研究。基于ABAQUS有限元对平面板桩问题进行了分析,研究表明板桩两侧土压力满足共同变形理论,位移较小时p-y成线性关系,位移较大时p-y表现出明显的非线性,在此基础上拟合得到适合板桩的p-y曲线。将上述拟合p-y曲线引入杆系有限元法中,对天津港深水地连墙码头算例进行了计算。结果表明,p-y曲线法相比m法计算出的最大正弯矩和位移量均明显增大,最大负弯矩有所减小。综上所述,通过理论分析及有限元计算,对大型地连墙码头的计算理论进行了研究,提出了考虑锚碇点位移的计算模式,探讨了出现大位移后的p-y关系曲线,并均将其编制成杆系有限元程序,所得研究成果可为大型深水地连墙码头的计算理论提供参考。更多还原

【Abstract】 As one of three major types of wharf structure, sheet pile wharf has great advantages in structural strength, the construction speed and project cost. Due to the theoretical calculation and the construction technology is not perfect, our sheet pile wharf are more used for small and medium sized terminals. In order to meet large-scale, deepwater development situation, the theoretical calculation of the displacement of anchored point and the relationship of soil reverse force and displacement should be improved.The displacement of anchored point has obvious effects on the displacement of quay and the internal force of front wall. In order to calculate the displacement of anchored point and the internal force of front wall, based on the m method, a method called joint method is used for the calculation of sheet pile structure. In the joint method, both the front wall and the anchor wall are assumed as elastic foundation beam, and the anchor rod is divided into truss element.The problem is convert to plane framework, and be solved as a whole.Calculation results indicate that the displacement value and the internal force of front wall can be fitted the observational data well. The displacement of anchored point can be reflected from the results. The negative moment of the front wall significantly increase. The deformation of anchor rod is the main factors causing the displacement of anchored point in the deep water quay. Joint method is more suitable for the calculation of sheet pile structure.In large displacement conditions, the relationship between soil reaction p and horizontal displacement y need to be studied. The plane strain state of sheet pile wall has been analyzed using ABAQUS software, the results show that the earth pressure on both sides of the wall satisfies common deformation theory, the relationship of the soil reaction and horizontal displacement are line related in small displacement condition, while it is nonlinear related in large displacement condition. On this basis, the p-y curve of sheet pile wall is fitted.Tianjin deepwater wharf examples are calculated with the truss finite element method, which with consider nonlinear p-y curve. The results indicate that the maximum value of both the positive bending moment and displacements calculated with p-y curve method is bigger than it calculated with m method, but the maximum value of negative bending moment is smaller.In summary, based on theoretical analysis and finite element calculations, the calculation method in the underground continuous wall is studied, a new calculation mode with consider the displacement of anchored point is proposed, the p-y curve of sheet pile wall is fitted in this paper. The research results could be provided for the theoretical calculation of lager diaphragm wall.更多还原