不同荷载比及跨度下新型张弦梁结构的用钢量分析

STEEL CONSUMPTION OF NOVEL BEAM STRING STRUCTURES WITH DIFFERENT LOAD RATIOS AND SPANS

对比研究了采用交叉撑杆和管内穿索下弦的新型张弦梁结构的受力性能与用钢量。通过建立多个张弦梁结构模型并开展有限元分析,明确两类张弦梁结构在不同荷载比下的结构极限承载力变化规律和设计准则。在不同荷载比和跨度条件下,优化设计两类张弦梁结构,对比结构用钢量。结果表明:半跨可变荷载时,新型张弦梁结构的极限承载力会随着荷载比的增大而增大;新型张弦梁多由构件应力准则控制,而传统张弦梁结构设计多由位移准则控制;一般跨度和荷载比的新型张弦梁结构平均用钢量仅为传统张弦梁结构的71%。

A comparative study was conducted on the mechanical performance and steel consumption of a novel beam string structure with cross bracings and lower chord with cables in tubes.The law of changes in structural ultimate bearing capacity and criteria of design control of two beam string structures at different load ratios were determined by establishing multiple models and conducting finite element analysis.Considering different spans and load ratios,the design of two beam string structures were optimized,followed by comparison of steel consumption.Results show that the ultimate bearing capacity of the new beam string structure will rise as the load ratio increases within a half span;most new beam string structures are controlled component stress criteria,while conventional beam string structures;and in common load ratios and spans,the average steel consumption of new beam string structures is only 71%of that of conventional beam string structures.