【摘要】 目前美国的桥梁设计规范在考虑重力荷载和卡车荷载组合时分别采用1.25和1.75的系数,但是当考虑地震荷载作用时,取地震系数1.0,一般不考虑卡车荷载,特殊情况需要考虑时卡车荷载系数为0.5。这说明地震与卡车组合时候,其概率理论的不完备性。基于此,参考文献[16,17]不仅给出了地震和重卡车作用下的组合理论,还给出其共同作用下荷载系数的计算方法。本文的主要目的是用一个典型桥梁实例对求解的荷载系数进行检验。通过有限元软件对采用新的荷载系数的桥墩截面配筋进行重新设计,然后,对新桥进行地震作用下的pushover分析,并与现行LRFD规范的规定值进行对比。结果表明,新的荷载系数能够保证桥梁结构的安全,可以按其设计。更多还原

【Abstract】 The current Guide Specification for LRFD Seismic Bridge Design uses 1. 25 for dead load and 1. 75 for truck load,but 1. 0 for earthquake alone or 1. 0 earthquake and 0. 5 times truck load for special conditions when considering earthquake effects,which indicates that the probabilistic theory for earthquake and heavy truck load combination is not complete. Based on which,papers[16,17]present the theory for their combination and the method for load factor calculation. The purpose of this paper is checking the load factor calculated by the new method using a typical bridge case study. The reinforcement of the bridge pier is redesign using the new load factors through element software. The pushover analysis of the redesign pier is carried on and the results are compared with those of LRFD. The results show that the new factor can ensure the safety of the bridge and can be employed in seismic bridge design.更多还原