交通荷载作用下饱和土体中衬砌隧道系统的动力响应研究

发布时间：2018-01-24 15:07

本文关键词： 衬砌隧道交通荷载饱和土体道床板浮置板邻近隧道　出处：《南昌大学》2015年博士论文　论文类型：学位论文

【摘要】：由于铁路建设和城市轨道交通的迅猛发展,交通荷载作用下地下隧道系统的动力响应以及由此产生的环境影响越来越受到公众的关注。针对富水地区中的隧道系统,基于饱和土体的Biot理论,考虑隧道衬砌与外围土体的作用,分析了交通荷载作用下衬砌隧道系统的动力响应,主要包括以下几点内容：1.将列车载重作为移动恒载并沿圆周平均布置,使交通荷载简化为轴对称荷载,把隧道衬砌视为连续弹性体,根据Helmholtz势函数的矢量分解理论以及傅里叶积分变换解耦衬砌隧道系统的控制方程,结合边界条件和连续条件求得频率-波数域内衬砌、土体动力响应的解析解,然后利用傅里叶积分逆向变换求得时间-空间域内饱和土体中衬砌隧道系统动力响应的数值解。通过与相关文献比较,验证了本文方法的正确性,揭示衬砌对隧道系统动力响应具有显著影响,同时讨论了荷载速度、衬砌与饱和土体的弹性模量比值、土体骨架与孔隙流体间的相互作用力参数对衬砌隧道系统动力响应的影响。2.在点荷载形式的交通荷载作用下,将隧道衬砌视为Flugge薄壁圆柱壳,将点荷载、衬砌隧道系统的动力响应均沿环向模态展开成傅里叶级数形式,利用Helmholtz矢量分解理论、傅里叶积分变换、边界条件和连续条件,求解了竖向移动简谐点荷载作用下饱和土体中衬砌隧道系统的动力响应,分析了动力响应在环向的分布规律,并探讨了荷载速度、荷载初始频率对动力响应应的影响。研究结果表明这种方法可有效求解非轴对称的交通荷载作用下饱和土体中衬砌隧道系统的动力响应。在此基础上,将道床板、浮置板和轨道视为Euler梁,利用卷积积分的傅里叶变换性质,求解了竖向简谐点荷载作用下饱和土体中无砟轨道衬砌隧道系统和浮置板轨道衬砌隧道系统的动力响应,计算结果显示这个方法也可以求解饱和土体中无砟轨道隧道系统和浮置板轨道隧道系统的动力响应,通过与衬砌隧道系统的动力响应比较,分析了道床板、浮置板和轨道对动力响应的作用。3.在前面研究的基础上,将饱和土体中平行双衬砌隧道系统分解成双衬砌子系统和双隧洞子系统。根据傅立叶级数展开的理论,将点荷载、动力响应均分解成正对称部分和反对称部分。考虑饱和土体中两个隧道的相互作用,并把外围饱和土体的动力响应转换成两个单隧洞系统动力响应的叠加,根据两个衬砌与土体接触面处的连续条件和边界条件,求解了饱和土体中左右平行、上下平行双衬砌隧道系统的动力响应。通过与单衬砌隧道系统的动力响应比较发现邻近隧道对饱和土体中双衬砌隧道系统的动力响应具有显著影响,并讨论了荷载频率、隧道间距等对动力响应的影响。
[Abstract]:Due to the rapid development of railway construction and urban rail transit. The dynamic response of underground tunnel system under traffic load and its environmental impact have attracted more and more attention of the public. For the tunnel system in water-rich area, the Biot theory based on saturated soil is used. Considering the effect of tunnel lining and surrounding soil, the dynamic response of lining tunnel system under traffic load is analyzed, which includes the following points: 1. Take the train load as moving dead load and arrange along the circular average. The traffic load is simplified to axisymmetric load and the tunnel lining is regarded as a continuous elastic body. According to the vector decomposition theory of Helmholtz potential function and the control equation of the decoupled lining tunnel system with Fourier integral transform, the internal lining in frequency-wavenumber domain is obtained by combining the boundary condition and the continuity condition. The analytical solution of soil dynamic response and the numerical solution of dynamic response of lining tunnel system in saturated soil in time-space domain are obtained by using Fourier integral inverse transform. The correctness of this method is verified and the influence of lining on the dynamic response of tunnel system is revealed. At the same time, the load velocity and the ratio of elastic modulus of lining to saturated soil are discussed. The influence of interaction force parameters between soil skeleton and pore fluid on the dynamic response of lining tunnel system. 2. Under the traffic load of point load, the tunnel lining is regarded as Flugge thin-walled cylindrical shell. The point load and the dynamic response of the lining tunnel system are all expanded into Fourier series form along the toroidal mode, using the Helmholtz vector decomposition theory, Fourier integral transform, boundary conditions and continuous conditions. The dynamic response of lining tunnel system in saturated soil under the action of vertical moving harmonic point load is solved. The distribution of dynamic response in circumferential direction is analyzed and the load velocity is discussed. The results show that this method can effectively solve the dynamic response of lining tunnel system in saturated soil under non-axisymmetric traffic load. The track bed plate, floating plate and track are regarded as Euler beams, and the Fourier transform property of convolution integral is used. The dynamic responses of ballastless track lining tunnel system and floating slab track lining tunnel system in saturated soil under vertical harmonic point loading are solved. The results show that this method can also solve the dynamic response of ballastless track tunnel system and floating slab track tunnel system in saturated soil. The effect of floating plate and track on dynamic response. 3. Based on the previous study. The parallel double lining tunnel system in saturated soil is decomposed into double lining subsystem and double tunnel subsystem. The dynamic response is decomposed into normal symmetric part and antisymmetric part. Considering the interaction of two tunnels in saturated soil, the dynamic response of the peripheral saturated soil is transformed into the superposition of the dynamic response of two single tunnel systems. According to the continuous condition and boundary condition of the interface between two linings and soil, the left and right parallelism in saturated soil is solved. By comparing with the dynamic response of single lining tunnel system, it is found that the adjacent tunnel has a significant effect on the dynamic response of double lining tunnel system in saturated soil. The influence of load frequency and tunnel spacing on dynamic response is also discussed.
【学位授予单位】：南昌大学
【学位级别】：博士
【学位授予年份】：2015
【分类号】：U451

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