连续化上部结构的高铁桥采用功能分离型支座的抗震性能研究

发布时间：2018-11-12 11:21

【摘要】：随着我国经济的飞跃发展,高速铁路的建设也进入一个全新的阶段,遍布我国的高速铁路网逐渐成型。作为高速铁路的特点之一就是大量的高架铁路桥。有些地区高架桥的比例高达80%以上。我国高速铁路建设速度快的同时,也有一些需要进一步提高完善的问题。我国地域辽阔,有很多高速铁路建设在地震多发且高烈度的地区。而我国还没有针对高速铁路桥的专用的设计规范,因此针对高速铁路桥在强震作用下的破坏机理和提高高速铁路桥梁抗震性能的研究十分必要。本文就是在这个前提下,针对高速铁路桥的破坏机理进行初步理论研究的同时,提出了全新的采用功能分离支座来提高高速铁路抗震性能的方法。首先连续化高速铁路桥梁的上部结构且改变支座为功能分离型新型支座,使高速铁路桥墩在强震作用下处于基本弹性状态以保证高速铁路桥的地震安全性。针对一座既有高速铁路桥梁进行了有限元分析验证了本方法的有效性。本文的主要研究内容如下:1、以按照现行铁路桥梁设计规范设计的跨度为32米的既有高速铁路桥梁为对象,建立了SAP2000的有限元模型。为了提高桥梁体系的抗震性能,将上部结构连续化,连续化跨数考虑3,5,6,8跨,以得到最优化的连续跨数。有限元分析时地震作用输入考虑了单向、双向以及三向地震动。输入加速度为9度罕遇地震动峰值加速度的0.64G。通过线性动力时程分析,研究地震动的输入方向组合对结构主要控制指标的影响2、针对连续化的桥梁,采用纤维铰模型进行非线性动力时程分析,分析工况为水平地震作用为0.2G、0.3 G、0.45 G、0.57 G、0.64 G。1)综合墩底反力、墩顶位移、上部梁端位移的地震响应,确定桥墩进入屈服状态的地震动水准。2)设置经参数优化后的新型隔震支座,进行非线性动力时程分析,确定连续化的最优化跨数。3、将功能分离型支座通过有限元软件模拟在已建成的简支梁型的高铁桥梁上,进行有限元分析验证了本方法的有效性,验证功能分离型支座的方便可行。
[Abstract]:With the rapid development of China's economy, the construction of high-speed railway has entered a new stage. As one of the characteristics of high-speed railway, a large number of elevated railway bridges. In some areas the proportion of viaducts is as high as 80% or more. With the rapid construction of high-speed railway in China, there are some problems that need to be further improved. China has a vast territory and many high-speed railways are built in areas with high earthquake intensity. However, there is no special design code for high-speed railway bridge in China, so it is necessary to study the failure mechanism of high-speed railway bridge under strong earthquake and to improve the seismic performance of high-speed railway bridge. Based on this premise and the preliminary theoretical study on the failure mechanism of high-speed railway bridge, a new method of improving seismic performance of high-speed railway by using functional separation support is put forward in this paper. Firstly, the superstructure of high-speed railway bridge is continuously changed and the support is changed into a new type of functional separation support, which makes the pier of high-speed railway bridge under strong earthquake in a basic elastic state to ensure the seismic safety of high-speed railway bridge. The effectiveness of this method is verified by finite element analysis of an existing high-speed railway bridge. The main contents of this paper are as follows: 1. The finite element model of SAP2000 is established for the existing high-speed railway bridges with a span of 32 meters designed according to the current railway bridge design code. In order to improve the seismic performance of the bridge system, the superstructure is continuous and the continuous span number is taken into account in order to obtain the optimum continuous span number. In finite element analysis, unidirectional, bidirectional and triaxial ground motions are taken into account in seismic input. The input acceleration is 0.64 GG of the peak acceleration of 9 degrees rare ground motion. Through the linear dynamic time history analysis, the influence of the input direction combination of the ground motion on the main control index of the structure is studied. 2. For the continuous bridge, the nonlinear dynamic time history analysis is carried out by using the fiber hinge model. Under the condition of horizontal earthquake, the seismic response of the bottom of the pier, the displacement of the top of the pier and the displacement of the end of the upper beam is synthesized. Determine the level of ground motion at which the pier enters the yield state. 2) set up a new type of isolation bearing after parameter optimization, carry out nonlinear dynamic time history analysis, and determine the continuous optimum span number. The functional separation support is simulated by finite element software on the bridge with simple beam. The validity of the method is verified by finite element analysis, and the convenience and feasibility of the functional separation support are verified.
【学位授予单位】：广州大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：U442.55

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