【作者】 杨书燕；

【导师】 姜忻良；

【作者基本信息】 天津大学 ， 结构工程， 2006， 博士

【摘要】 随着经济建设的快速发展,天津市提出了对海河两岸进行开发规划,规划中大量建筑物和地下工程将沿河而建。在地震作用下,这些地下工程及河流的存在将使附近建筑物的动力反应受到影响,对其进行研究将具有十分重要的理论和实际工程意义,为此本文结合天津市海河两岸实际情况,主要做了以下几个方面的研究工作:(1)确定了适合本文相互作用动力分析的土体、结构弹塑性本构模型,推导了土体、结构的弹塑性矩阵表达式和流体有限元矩阵的表达式,构建了特殊地形上土-结构相互作用体系的弹塑性整体有限元模型,确定了有限元网格划分的大小和动力时程分析的解决方案,在ANSYS中成功实现了粘弹性边界的模拟和重力的引入。(2)研究了河流对周围场地地震反应特性的影响和地层中间带有软、硬夹层对场地地震反应的影响。结果表明河流的存在使周围场地地表地震反应比一般自由场时有所增大,河流越深这一现象越明显;软夹层的存在使一般自由场和有河流场地地表位移反应增大,土体剪应力减小,软夹层处土体位移发生突变;而硬夹层对场地动力反应的影响程度很小。(3)分析了地震作用下河流对不同场地类型、不同土层分布、不同基础形式的相互作用体系动力反应的影响,结果表明,建筑物距河流越近,地震作用下体系的顶层总位移、基底平动和摆动越大;弹塑性分析时结构顶层总位移、基础的平动和摆动都发生了向河流一侧不可恢复的偏移,当土体中存在软弱夹层时,偏移现象更明显;浅基础体系偏移大于深基础,并导致上部结构受力不对称。(4)通过分析建筑物正下方不同宽度隧道对其地震反应的影响和隧道对不同基础形式建筑物地震反应的影响发现,隧道在建筑物正下方时,随着隧道宽度增加,上部结构顶层总位移反应增大;隧道紧靠建筑物一侧且基础埋深较浅时,上部结构易发生向无隧道一侧的不可恢复偏移,并导致上部结构受力不对称,而深基础相互作用体系未发生明显偏移。(5)在特殊地形上进行土-结构动力相互作用的实际工程分析时,为缩小计算规模,运用了分支模态二步分析法,事实表明该方法能很好地与现有广泛流行的结构设计软件相结合,为工程设计考虑相互作用影响提供了有效途径。更多还原

【Abstract】 With quickly economic development, Tianjin has established program to exploit Haihe riversides. I n the program, buildings and underground engineering will be developed. Underground engineering and river will influence the dynamic characteristics of the nearby building, it is important both in theory and engineering to study that, so this paper will research the following problems.(1) This paper chooses nonlinear constitutive models of soil and building, derivates finite-element matrixes of soil, building and fluid, sets up the integral finite- element interaction model on special site, finds dynamic time history analysis method. Through calculating, ascertains finite-element grid size. Implements the viscoelastic boundary and consider gravity in ANSYS.(2) By studying the effect of river and soft or hard sandwich to site, it can be shown that ground earthquake response increases around river, And the deeper the river is, the more obvious that is. Soft sandwich makes ground displacement increase, shearing strength reduced, and site displacement changes abruptly in that place. Hard sandwich affects ground response little.(3) Under seismic excitation, river will affect the reaction of interactive system. When the structure closes river, the movement and swing of superstructure increase obviously. For nonlinear system, the superstructure takes place irreclaimable excursion to the river, the excursion is more obvious on the site having soft sandwich. Superstructure with shallow foundation excurses more than that with deep foundation, the excursion may make superstructure dissymmetrical force.(4) When tunnel is under building, the wider tunnel is, the bigger building move. When the structure closes river, for the structure with shallow foundation, which may take place irreclaimable excursion to the no-tunnel side, which will cause loading distribution asymmetry in the structure, but for the structure with deep foundation, the phenomena is not obvious.(5) When analyze fact engineering on special site, in order to reduce calculating workload, Two steps method branched inertia coupling is used, The results show which can combine with popular structure design software well, and supply available approach for engineering design.更多还原