公路钢箱梁定位安装精度控制技术研究

本篇文章主要以某公路钢箱梁建设为例,全面阐述了钢箱梁的定位安装精度控制技术的使用方法,进而再探索出当前公路钢箱梁建设里面定位安装精度控制的一些较为具体的问题,并提出效果较佳的解决措施,在实行了合适的定位安装精度控制举措之后,确认了钢箱梁的定位安装效果,保障了公路项目建设的整体质量以及相应的应用安全。

公路钢箱梁正交异性板桥面国内外规范荷载作用局部应力计算与比较

针对适于公路钢箱梁正交异性板桥面局部应力计算的车辆轮轴荷载,分析中国、美国、加拿大、日本、英国和欧洲桥梁设计相关规范之间的差异。选择8种规范荷载,根据车轮触地面积,考虑50mm厚铺装层对荷载的扩散效应,确定各规范荷载的加载面积。选择钢箱梁典型结构,计算各荷载作用下桥面局部应力,对吊索中点加载模式,比较该位置顶板顶、底面横向应力和纵肋底面纵向应力;对吊索支点加载模式,比较顶板顶、底面纵向应力。最后,不考虑铺装层扩散效应,进一步计算比较各荷载作用下的上述应力。研究表明,按照我国公路I级荷载计算所得桥面局部应力偏低,加载面积的形状和大小对桥面局部应力影响明显。

公路钢箱梁焊接变形控制技术研究

近年来,随着焊接技术特别是CO2气体保护焊接技术在公路钢箱梁制造中的应用越来越广泛,生产效率和焊缝质量提高的同时,也带来诸如焊接变形加剧且难以控制的负面影响。本文通过工程实例阐述了合理运用焊接反变形技术,抵消焊接变形,达到提高产品几何尺寸精度的目的。

城市公路钢箱梁制造过程中焊接变形的控制

整体钢箱梁安装完毕后各项指标均符合设计规范要求,可供类似钢箱梁高架桥的施工参考。

Study in the design and manufacture process of the elastic cable anchor box in steel box girder of Taizhou Bridge

Taizhou Yangtze River Highway Bridge is a large span suspension bridge with three pylons. The elastic cables are installed to connect the steel tower and the steel box girder. The constraints can increase the safety coefficient of the middle saddle, and improve the stress conditions of the middle pylon and decrease the deflection in the middle of the main girder, as well as the longitudinal displacement of the main girder caused by live loads. The anchorage boxes of the elastic cable are installed in the wind fairing outside the vertical web plate of the box girder. Two anchor boxes form a pair and are arranged parallelly. Eight anchor boxes are installed in the bridge. In this paper, the design scheme and the technical difficulties in manufacturing are briefly discussed with the precision control techniques.

Design of steel box girder for Taizhou Yangtze River Highway Bridge

Taizhou Yangtze River Highway Bridge is the first three-pylon two-span suspension bridge in China. The main girder adopts flat steamline steel closed box girder which has well wind-resistant capability and is technically mature besides beautiful appearance. Straight web plates of the steel box girder in longitudinal direction are proposed in order to ensure the integrity of the steel box girder, and to keep the stress of the steel box girder continuous in the middle pylon, as well as to reduce the gradient of the middle pylon columns. The cross section of the box girder has one box with three cells. Solid-web diaphragm plate with good integrity and high torsional stiffness is adopted. The lifting lugs are utilized in the anchors of suspender cable. In this paper, selection of the cross section of the steel box girder, the general structure design, local structure design and main structure calculation results of Taizhou Yangtze River Bridge are introduced emphatically.

T型接头部分熔透坡口角焊缝UT检验方法研究

在公路钢箱梁制造中广泛采用坡口角焊缝,这类焊缝允许焊根处有局部未焊透。为满足使用要求,保证焊接质量,常常要求对焊缝进行超声波探伤(UT)。针对未焊透尺寸的UT检测方法进行讨论,以选择合理的检测方法和检测工艺,使焊接接头中未焊透尺寸能够通过超声检测被控制在允许的范围之内。