摘要
Abstract
The continuous beam bridge over Tanglai canal and Fenghuangsouth street is the approach bridge of the Yellow River grand bridge of Yinchuan-Xi'an Railway,the new truss girders were used as temporary structural support.In this paper,the new truss girder is regarded as re-search object.Midas and theoretical calculation are employed to conduct internal force analysis and stability checking calculation for primary truss,cap beam,steel tube pile and drilled pile in this structural support system.The computed result shows that the maximum axial force of chord member in primary truss is 56.0%of permissible value;the maximum axial force of montant is 69.7%of permissible value;the maxi-mum axial force of diagonal is 44.9%of permissible value;the maximum deflection is 36%of permissible value;the maximum normal stress of cap beam is 69.4%of design value;the maximum shearing strength is 82%of design value;the stability of steel tube pile,bearing capacity and settling volume of drilled pile meet safety requirements.This engineering practice proves that the pivotal construction technique of the new truss girder support system is feasible.The internal force analytical method of the new truss girder support system is introduced in this paper and it can provide references for further application and optimum structural design.关键词
新型组合式桁梁/主桁架/最大轴力/挠度/稳定性Key words
New type of composite beams/Primary truss/Maximum axial force/Deflection/Stability分类
建筑与水利
