部分地锚式悬索桥的基本结构性能

Basic Structural Performance of Partially Anchored Suspension Bridge

摘要:

为了拓展自锚式悬索桥的适用范围，在传统地锚式和自锚式悬索桥的基础上，提出了一种新型的部分地锚式悬索桥，并对该结构体系的基本性能进行了研究。主要研究内容包括基于挠度理论的结构分析、静力性能和自振特性、锚碇设计方法等。研究结果表明，部分地锚式悬索桥结构的静力性能介于地锚式悬索桥和自锚式悬索桥之间，其重力刚度由成桥状态时的锚索拉力提供；活载作用下主缆的内力增量在锚索和主梁中按照刚度分配，体现了“部分地锚”的特点；该体系可以通过主动张拉锚索来调整结构受力状态，并且通过发挥被动土压力的有利作用可以减小重力式锚碇的体量。部分地锚式悬索桥特别适用于建设条件受限的特殊桥位，可张拉调整的锚索为设计和施工提供了新的方案，并具有一定的优势。

Abstract:

In order to extend the application of self-anchored suspension bridge， a novel type of partially anchored suspension bridge was proposed based on externally anchored suspension bridge and self-anchored suspension bridge， and the basic performance of the structural system was studied. The main research contents include structural analysis based on the deflection theory， parameter analysis of static performance， natural vibration characteristics， and design method of anchorage. The results show that the static performance of partially anchored suspension bridge is between the externally anchored suspension bridge and the self-anchored suspension bridge， and the gravity stiffness is provided by the anchor cable tension when the bridge is formed. Under the action of live load， the increment of internal force of main cable is distributed in the anchor cable and the main beam according to their stiffness， which reflects the characteristics of “partial anchor”. The structural system can adjust the force state by actively tensioning the anchor cable， and the beneficial effect of passive earth pressure can reduce the weight of gravity type anchorage. Partially anchored suspension bridge is especially suitable for special positions with limited construction conditions. The tensioned and adjustable anchor cables provide a new scheme for design and construction. It can be concluded that partially anchored suspension bridge has certain advantages.