自锚式悬索桥空间主缆线形的计算方法

基于空间分析模型,研究了自锚式悬索桥空间主缆线形的精确计算方法,根据主缆在吊杆之间的各索段在自重作用下呈悬链线,推导并研究了空间主缆在吊杆力作用下坐标的迭代计算方法.根据主缆空间线形及其理论交点,确定合理的鞍座位置,根据主缆无应力长度不变的原则,确定主缆的空缆线形.基于上述理论,以某空间缆索自锚式悬索桥为例,进行了详细的分析,给出了主缆无应力长度、鞍座位置、鞍座预偏量等,确定了该桥的合理成桥状态及空缆状态时的线形.算例分析表明:空间缆索自锚式悬索桥主缆线形计算方法是正确、可行的.

Calculation Method for the Shape-Finding of Self-Anchored Suspension Bridge with Spatial Cables

Based on the spatial model,a reliable and accurate calculation method for the shape-finding of self-anchored suspension bridge with spatial cables was studied.On the principle that the shape of the main cable between hangers is catenary,the iteration method of calculating the coordinates of the spatial main cable under the action of hangers was deduced.The reasonable position of the saddle was determined according to the shape and the theoretical joint point(IP) of the main cable.The shape of the main cable at the cable finish stage was presented,based on the unchanging principle of the zero-stress length of the main cable.Based on the above theory,some self-anchored suspension with spatial cables was demonstrated.The zero-stress length of the main cable,the position of the saddle and the pre-displacement of the saddle were given.And the reasonable shape of the main cable at the bridge completion stage and the cable finish stage was presented.The analysis of some examples demonstrates that the shape-finding calculation method presented is accurate and feasible.