曲线钢箱梁桥面板力学行为及构造优化研究

Research on the Mechanic Behavior and Detail Optimization for Deck of Steel Curved Box Beam

研究目的:小半径曲线钢箱梁桥正交异性钢桥面板构造繁复,弯扭耦合作用下受力特性极为复杂。为了探究该类型桥面板力学特性,并提出合理构造优化建议,本文依托西安市某立交小半径曲线钢箱梁匝道桥,采用数值分析方法研究局部荷载作用下曲线钢箱梁桥面板力学行为,并基于正交试验方法,利用IntelliJ IDEA软件开发曲线钢箱梁桥面板构造优化程序,实现桥面板多目标构造参数优化。研究结论:(1)边跨最大正弯矩截面为大多数控制细节的最不利荷载控制截面,其中车轮荷载作用于边跨最大正弯矩位置时控制细节3(横隔板过焊孔圆弧位置)的主应力明显大于最大负弯矩和零弯矩位置,且车轮荷载作用于曲线钢箱梁外侧会增大桥面系应力;(2)车轮荷载作用于纵肋正上方和中间时产生的各控制细节主应力较相近,但作用于横隔板中间与正上方造成的局部应力具有显著差异,进而确定曲线钢箱梁正交异性桥面板各控制细节的最不利荷载作用位置;(3)通过多目标优化构造运算确定的曲线钢箱梁正交异性组合桥面板的合理构造,可显著改善桥面板力学特性;(4)本研究成果可为曲线钢箱梁正交异性桥面系构造设计和养护方法提供优化建议。

Research purposes:It is extremely complex for the details in the orthotropic deck of the steel curved box beam with small radius,with the complicated mechanic behavior under the bending and torsion.In order to investigate the mechanical performance of orthotropic deck of the steel curved box beam with small radius,and provide the optimized details for this type of bridge deck,this paper conducted a detailed study in the mechanical performance of this kind of orthotropic deck subjected to the wheel load with the numerical analysis.In addition,the multi-objective optimization in the steel bridge deck was launched using orthogonal test,as well as developing software for the optimization of the orthotropic deck of the steel curved box beam with IntelliJ IDEA.Research conclusions:(1)The largest bending moment section in side span is the most critical for the main stresses in the most key details,with the obvious large stress in the detail 3(the welding hole arc in diaphragms).Besides,as the wheel load on the raised side,the stresses of orthotropic deck are larger than those,as the load in the middle.(2)The main stresses in the critical details are almost identical as the wheel load on and between the ribs,yet the stresses are great different as the load on or between the diaphragms and each critical load position for these details are obtained.(3)For the curved steel box beam,the new steel-concrete composite bridge deck,with muti-objective optimization details,has much better mechanical performance than the steel orthotropic deck.(4)The research results can provide the optimization for the design and maintenance for the orthotropic deck on the steel curved box beam.