错孔拓宽连续箱梁力学性能分析

Analysis of Mechanical Properties of Continuous Box Beam with Staggered Hole Widening

由于在高速公路扩建工程中,采用错孔拼接拓宽设计方案与常规桥梁拓宽有较大不同,为验证该方案的可行性,针对该错孔拓宽方案开展了计算研究。结果表明:桥梁错孔拓宽布置,可以有效降低新旧桥梁翼缘板端的高差,改善旧桥正弯矩区受力,但会增加旧桥支座处的负弯矩;新旧桥梁的拼接宜优选铰接形式;桥梁拼接拓宽后恒载增大,可不必担心支座脱空问题;拓宽桥梁延迟拼接,可以有效减少桥梁拼接运营后发生的横纵向位移,但改善效果会随着时间增长而逐渐降低。

Considering in the project of expresswayexpansion,the design scheme of widening with staggered holes is quite different from that of conventional bridge widening,a calculation study was carried out on the scheme of widening with staggered holes in order to verify its feasibility.The results show that the bridgewidening with staggered holes can effectively reduce the height difference of the flange end of the new and old bridges and improve the force in the positive bending moment area of the old bridge,but it will increase the negative bending moment at the support of the old bridge;the form of articulationis preferred in the splicing of new and old bridges;after the bridge splicing is widened,the dead load increases,so there is no need to worry about the bearing vacancy;delaying the splicing of bridges can effectively reduce the horizontal and vertical displacements that occur during the operation of the bridges,but the improvement effect will gradually decrease with time.