铁路梁桥A形超高桥墩概念设计研究

Study of Conceptual Design of A-Shape High-Rise Pier of Railway Bridge

为给铁路梁桥A形超高桥墩构造尺寸的拟定提供参考,对该类桥墩的概念设计进行研究。从构造细节出发,分析对A形墩受力特性及经济指标有重要影响的设计参数,并利用ANSYS参数化设计建模平台对主要设计参数的合理取值进行优化设计分析,在此基础上总结各种墩高条件下A形墩的设计步骤和设计原则。研究结果表明:A形桥墩适用于墩高大于100m的铁路桥梁;调整A形墩单柱墩体坡率和两支腿底部横向中心间距可在不增加墩身混凝土体量的同时,显著提高A形墩横向刚度;A形墩墩顶、支腿顶、支腿底截面尺寸对A形墩经济性影响显著,应根据构造和强度要求优化设计。

To provide reference for determination of the structural dimensions of the A-shape high-rise pier of railway bridge, the conceptual design of such type of the pier was studied. Pro- ceeding from the structural details of the pier, the design parameters that could have important in- fluences on the mechanical characteristics and economic indices of the pier were analyzed and the reasonable values selected for the principal design parameters were optimized and analyzed, using the parameterized design modeling platform of ANSYS. On the basis of the analysis, the design procedures and design principles of the pier under various pier height conditions were summarized. The results of the study indicate that the A-shape high-rise pier is applicable to the railway bridge to have the piers higher than 100 m. The adjustment of the slope ratio of a single leg and the trans- verse center-to-center distance between the two leg footings of the pier can significantly improve the transverse rigidity of the pier without the need of increasing the concrete amount of the pier proper. The sectional dimensions of the top, leg tops and leg footings of the pier can have signifi- cant influence on the economy of the pier and the dimensions of the pier should optimally designed according to the structural and strength requirements of the pier.