杭温铁路楠溪江主跨240 m混凝土斜拉桥设计

Design of 240 m Main Span Concrete Cable-stayed Bridge on Nanxi River of Hangzhou-Wenzhou Railway

新建杭州—温州铁路(义乌—温州段)工程楠溪江特大桥主桥采用(40.5+79.5+240+79.5+40.5)m双塔双索面混凝土斜拉桥,半漂浮体系,主梁为预应力混凝土单箱单室截面,H形桥塔,平行双索面,索塔锚固采用钢锚箱。对主桥地理位置、技术标准及结构设计进行详细阐述,使用有限元分析软件对主桥进行结构检算,建立实体模型分析桥面板受力特点,并研究混凝土斜拉桥工后徐变变形控制措施。研究结果表明:该桥结构受力合理,各项指标均满足规范要求;桥面板以横向受力为主;通过调整斜拉索索力和主梁底板预应力钢束,可以控制主梁后期收缩徐变,且调整斜拉索索力方式控制效果更加明显。

The main bridge of the Nanxi River Super Major Bridge in the Yiwu-Wenzhou section of the Hangzhou-Wenzhou railway project adopts(40.5+79.5+240+79.5+40.5)m double-tower and double-cable-plane concrete cable-stayed bridge with semi-floating system.The main beam is a prestressed concrete structure with single box single room section.H-shaped bridge tower and parallel double-cable-plane are adopted,and steel anchor box structure is employed in the cable-tower anchorage zone.The geographical location,technical standards and structural design of the main bridge are expounded in detail.Finite element analysis software is used to check the main bridge structure,a solid model is built to analyze the characteristics of the bridge deck,and control measures of shrinkage and creep on prestressed concrete cable-stayed bridge are studied.The results show that the structural force is reasonable,various indexes meet specification requirements,the bridge deck is dominated by lateral forces;by adjusting the force of the stay cable and increasing the area of the prestressed cable on the bottom of the main beam,the shrinkage and creep deformation can be reduced,and the effect of increasing the cable force becomes more obvious.