侧向支撑对腹板开洞钢拱平面外弹性屈曲的影响分析

腹板开洞钢拱通过设置侧向支撑可以阻止钢拱发生平面外弯扭屈曲,支撑刚度的大小会对钢拱屈曲临界荷载产生影响.采用有限元方法分析了不同荷载、拱脚条件、支撑类型和位置对钢拱平面外屈曲稳定的影响.研究表明：在刚性支撑情况下,钢拱屈曲临界荷载随支撑刚度增大而增大,铰支钢拱屈曲半波随支撑数量的增加而增加,当支撑数量为n时,会出现n＋1个屈曲半波.两种支撑类型共同工作时,在侧向刚度支撑足够的情况下,扭转支撑对钢拱平面外屈曲临界荷载的影响有限.当侧向支撑刚度达到临界支撑刚度时,其屈曲临界荷载不再随支撑刚度的增大而增大.

ANALYSIS OF INFLUENCE OF LATERAL SUPPORT ON OUT-OF-PLANE ELASTIC BUCKLING OF OPEN HOLE WEB STEEL ARCH

Steel arches with web openings can prevent the occurrence of out-of-plane bending distorting buckling through setting up lateral brace. The value of brace stiffness can impose an influence on the critical load of steel arches buckling. Research on the influence of different loads, arch springing conditions, and brace types and positions on the out of-plane buckling stability of steel arch was carried out with finite element method. The research findings showed that under the steel brace, the steel arch buckling critical load increased with the brace stiffness, and the hinged steel arches buckling half wave increased with the brace quantity. When the brace quantity was n, the buckling half wave was n＋ 1. When impacted by two types of braces and when there was enough lateral stiffness brace, the distortion brace had a limited influence on the critical load of steel arch out-of-plane buckling. When lateral brace stiffness reached the critical brace stiffness, its critical load no longer increased with the brace stiffness.