“321”贝雷钢桥结构的优化及其力学性能分析

Analysis of the Optimization and Mechanical Property of “321” Bailey Structure

“321”贝雷装配成小跨径的连续梁结构承受荷载时,支点位置的竖腹杆是最薄弱杆件。针对施工大型临时承重设施常用的6m、9m、12m及15m四种跨度的贝雷连续梁进行分析,首先采用MIDAS Civil有限元软件进行杆单元建模计算组合应力,对比“321”贝雷及三种备选优化方案的承载能力,选出最优方案。随后采用板单元建模进行局部细节分析,对比各计算对象的Mises等效应力最大值,进一步验证了优化方案的有效性。结果表明:将I8工字钢竖腹杆替换为双拼C10槽钢,使贝雷的重量增加19%,但承载力可提升50%左右。

The bearing capacity of Bailey truss is handicapped by its vertical bar upon fulcrum when constructing a continuous girder.Considering the common span of Bailey continuous girder,including 6 m、9 m、12 m and 15 m,prototypical Bailey and 3 optimizations is studied about their bearing capacity.A brief contrastive analysis,which is base on bar element analysis using MIDAS Civil,shows that optimization schemes are all effective.This result can be confirmed by a further study on Mises Equivalent Stress using plate element method.As a conclusion,the bearing capacity increases about 50% while weight increases only 19% if the vertical bar is made of C10 double Channel beam instead of I8 I-beam.