呼准铁路黄河特大桥引桥T形刚构桥设计研究

依托呼准铁路大路黄河特大桥北引桥2×52 m预应力混凝土T形刚构桥设计为背景,结合桥址实际情况,利用有限元程序着重对关键技术:引桥桥跨方案研究、结构静力特性、结构自振特性及结构罕遇地震下弹塑性抗震性能进行分析。通过研究得到以下结论:北引桥孔跨设计方案采用3联2×52 m T形刚构桥方案经济合理;结构构造及钢束布置形式合理;为保证墩底塑性铰区域的可靠性,应重视墩底的抗剪强度验算和箍筋配置;该桥结构强度、刚度及抗震性能等指标均符合规范规定,满足铁路运行安全要求。

The Design and Research of T-shaped Rigid Frame Bridge of Yellow River Bridge Approach on Hohhot-Zhungeer Railway

Based on 2 × 52 m prestressed concrete T-shaped rigid frame bridge of the north approach of Dalu Yellow River grand bridge on Hohhot- Zhungeer railway and in view of the situations of the bridge site,this paper analyzes emphatically the key technologies with finite element program,including the arrangement of bridge span,static behavior of the structure,free vibration characteristics of the structure and elastic- plastic seismic performances of the structure in case of rare earthquake. The research draws the conclusion as below: the design of 3 units of T-shaped rigid frame bridge of the north bridge approach is economical and reasonable; the structure details and steel tendon arrangement are rational. In order to ensure the reliability of the plastic hinge region of the pier bottom,shear strength checking and stirrups arrangement should be emphasized. The structural strength,stiffness and seismic performances of the bridge meet the specifications and satisfy the requirements for railway operation safety.