劲性索、桁架拱结构固有振动的相似性

采用有限元法对劲性索结构及由其倒置而成的桁架拱结构进行了固有振动分析,并与采用能量变分法对这2类结构固有振动分析得到的结果进行了比较,得到劲性索及桁架结构的固有振动具有相似性.在1个正弦半波的对称振型频率公式的基础上,推导了劲性索2个半波,3个半波和4个半波的频率计算公式.结果表明,给出的计算劲性索结构和桁架拱频率的公式具有很高的精度,误差均在5%以内,为劲性索和桁架拱结构的抗震与抗风验算提供了一种新的方法.

Similarities in natural vibration of stiff cable structures and truss arch structures

Natural vibration of stiff cable structures is analyzed based on FEM and the energy variation method,and the same is done to truss arch structures based on the new concept of upset stiff cable, from which the similarities of the two types of structures are obtained. Furthermore, the results of two methods are compared. The formulas of frequencies for stiff cable structures given by this paper are of high accuracy, and the formulas can be applied to truss arch structures, the differences of frequency are all within 5%. This provides a new method for evaluations on truss arch structures that resist earthquake and wind loads.