摘要
空腹式变截面连续梁桥V构存在下弦拉应力集中、易裂等问题,影响施工和运营期结构安全。文中以某V构钢混连续梁桥为工程依托,通过数值分析,开展了施工工艺的比选和桥梁成桥运营阶段的受力情况分析。结果表明:相较于其他施工方法,扣索支架联合施工方法可显著降低下弦拉应力,结构受力性能更为优越;将扣索初拉力从3000 kN提至5000 kN,充分利用扣索的初拉力,可将两侧扣索从7根减至4根;成桥运营阶段上、下弦结合处为关键截面,最大轴力工况下轴力约-5.34×10^(5)kN,在最大弯矩工况下弯矩约3.6×10^(5)kN·m,且对应最大压应力22.2 MPa,下弦墩顶处最大剪力约1.2×10^(5)kN,整体上、下弦均处于受压状态。因此,扣索支架联合施工法与其他方法相比不仅在受力性能上较优,且能够简化流程、提升经济性。
Traditional construction of the V-shaped structure in hollow-section continuous girder bridges is plagued by issues such as tensile stress concentration and susceptibility to cracking in the bottom chord.This paper takes a certain V-shaped steel-concrete continuous beam bridge as the engineering background.Through numerical analysis,comparison of construction techniques and analysis of the force conditions during the bridge’s completion and operation stage were carried out.Compared with other construction methods,the combined cable-stayed and support construction method can significantly reduce the tensile stress of the lower chord,and the structural mechanical performance is more superior.Increasing the initial tension of the cable-stays from 3000 kN to 5000 kN and making full use of this initial tension can reduce the number of cable-stays on both sides from 7 to 4.During the completed bridge operation stage,the joint of the upper and lower chords is a key section.Under the maximum axial force condition,the axial force is approximately-5.34×10^(5)kN;under the maximum bending moment condition,the bending moment is about 3.6×10^(5)kN·m,corresponding to a maximum compressive stress of 22.2 MPa.The maximum shear force at the top of the lower chord pier is roughly 1.2×10^(5)kN,and overall,both the upper and lower chords are in a compressive state.Therefore,compared with other methods,the combined construction method of cable-stays and supports is not only superior in mechanical performance,but also can simplify the process and improve economy.
作者
郭瑞孝
Guo Ruixiao(Xiamen Municipal Engineering Co.,Ltd.,Xiamen Fujian 361000,China)
出处
《山西建筑》
2025年第24期100-103,120,共5页
Shanxi Architecture
关键词
V形结构
连续梁桥
数值分析
V-shaped structure
continuous girder bridges
numerical analysis
