玛河电站桥梁式渡槽结构设计方法研究

发布时间：2018-02-17 05:49

本文关键词： 渡槽有限元分析模态分析动力时程分析　出处：《石河子大学》2014年硕士论文　论文类型：学位论文

【摘要】：渡槽是水利工程中应用比较广泛的建筑物，它实现了各个输水体系的连接，并且可以在不方便通过渠道的沟壑、河流地区实现水的运输。新疆兵团第八师玛纳斯河流域位于天山北坡经济开发区核心地带，流域总面积将近两万平方千米，玛纳斯河流域的开发工作从上个世纪五十年代开始，先后已经建成引水、输水、蓄水、发电等综合利用的水利水电工程，渡槽已成为这些工程的重要组成部分。基于此本文对新疆玛纳斯河一级电站工程中的其中一座桥梁式渡槽设计进行不同结构形式的对比分析得出了一些有意义的结论，包括以下几个方面：（1）对渡槽纵向结构形式进行对比，结果表明纵向选择等弯矩双悬臂式可以减小结构的弯矩和剪力，降低槽身的挠度，提高渡槽承载能力。（2）采用不同设计理论对槽体进行受力分析，并建立三维有限元分析模型，对无纵横梁渡槽和多纵梁渡槽进行对比得：渡槽在加设纵横梁后槽体和排架的内力变小，并且位移及应力分布更加均匀，改善了结构的受力情况。（3）应用流固耦合分析方法—Westergaard附加质量法考虑动水压力对渡槽的作用，对无纵横梁渡槽和多纵梁渡槽进行动力分析。进行模态分析提取前十阶振型和频率，并对振型和频率进行分析，结果表明多纵梁渡槽开始出现扭转振型的时间比无纵横梁渡槽推迟，说明加设纵横梁可以提高槽体刚度和抗震能力。改变渡槽内水位高度，得出随着渡槽内水位的升高，，渡槽结构整体质量增加，结构自振频率降低。（4）输入所在场地地震波，进行渡槽横向水平地震响应时程分析。分析不同结构形式的渡槽在地震波作用下特征点应力及位移变化情况，得出与无纵横梁渡槽相比多纵梁渡槽位移及应力最大值明显下降，并且波动比较慢。说明加设纵横梁提高了渡槽的抗震能力。总结：桥梁式渡槽既满足输水功能又满足交通功能，在自重、动水压力、车辆荷载、风荷载、地震作用的作用下对无纵横梁渡槽和多纵梁渡槽承载能力进行对比分析，结果表明与无纵横梁渡槽相比多纵梁渡槽节约了材料用量，改善了受力情况，提高了渡槽抗裂能力及抗震能力，所分析成果可为同类渡槽的结构设计提供参考。
[Abstract]:Aqueduct is a widely used building in water conservancy engineering. It realizes the connection of various water conveyance systems and can be used in gullies that are not convenient to pass through the channel. The Manas River Basin is located in the core of the economic development zone on the northern slope of Tianshan Mountain, with a total area of nearly 20,000 square kilometers. The development of the Manas River Basin began in -50s. Water diversion, water conveyance, water storage, electricity generation and other comprehensive utilization water conservancy and hydropower projects have been built. The aqueduct has become an important part of these projects. Based on this, this paper makes a comparative analysis of the design of one of the bridge aqueducts in the Manas River first Class Hydropower Station in Xinjiang, and draws some meaningful conclusions. These include the following:. The results show that the double cantilever with equal bending moment can reduce the bending moment and shear force of the structure, reduce the deflection of the aqueduct, and improve the carrying capacity of the aqueduct. (2) using different design theories to analyze the force of the tank body, and establishing the three-dimensional finite element analysis model, comparing the aqueduct without longitudinal and horizontal beam with that of the aqueduct with multiple longitudinal beams: the internal force of the trough and the bent frame becomes smaller after the aqueduct is installed with the longitudinal and horizontal beams. And the displacement and stress distribution is more uniform, which improves the stress of the structure. Using the fluid-solid coupling analysis method-Westergaard additional mass method to consider the effect of hydrodynamic pressure on the aqueduct, the dynamic analysis of the aqueduct without longitudinal and transverse beams and the aqueduct with multiple longitudinal beams is carried out. The modal analysis is carried out to extract the first ten modes and frequencies of the aqueduct. The vibration mode and frequency are analyzed. The results show that the time of torsional mode of multi-beam aqueduct is delayed than that of the aqueduct without longitudinal beam, which indicates that the stiffness and seismic resistance of tank can be improved by adding longitudinal and transverse beam, and the height of water level in aqueduct can be changed. It is concluded that with the increase of the water level in the aqueduct, the whole mass of the aqueduct structure increases and the natural vibration frequency of the aqueduct decreases. (4) input the seismic wave of the site and analyze the horizontal seismic response of the aqueduct in time history. The variation of stress and displacement of the aqueduct with different structure under the action of seismic wave is analyzed. It is concluded that the maximum displacement and stress of the aqueduct with multiple longitudinal beams are obviously decreased and the fluctuation is slower than that of the aqueduct without longitudinal and transverse beams, which indicates that the seismic capacity of the aqueduct is improved by adding the longitudinal and transverse beams to the aqueduct. Conclusion: bridge aqueduct meets both the function of water delivery and traffic. Under the action of deadweight, hydrodynamic pressure, vehicle load, wind load and earthquake, the load-carrying capacity of the aqueduct with no longitudinal and horizontal beams is compared with that of the aqueduct with multiple longitudinal beams, under the action of self-weight, dynamic water pressure, vehicle load, wind load and earthquake. The results show that compared with the aqueduct without longitudinal and transverse beams, the material consumption of the aqueduct is saved, the stress situation is improved, and the anti-crack and anti-seismic ability of the aqueduct is improved. The results of the analysis can provide a reference for the structural design of the aqueduct of the same kind.
【学位授予单位】：石河子大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：TV672.3

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