重载板梁结构弱翼缘贴角焊缝的可行性研究

Research on feasibility of fillet welding at weak flange in heavy-load slab and beam structure

重载桥式起重机板焊接主梁翼缘与腹板间焊缝受力复杂,对该焊缝进行合理设计是结构承载安全的关键之一。对于800 t桥式起重机主梁翼缘板厚51 mm、腹板厚16 mm时其间焊缝采用比国内标准推荐值小很多的8 mm单边贴脚焊缝的情况,通过用有限元子模型方法分析了焊缝应力分布,得到了较精确应力分析结果。子模型分析通过了壳-壳子模型验证整体模型网格疏密的精度。通过对壳-体子模型加接触分析,对焊缝进行了网格加密精确分析,验证了较厚翼缘板和较薄腹板焊接时采用更小焊脚尺寸角焊缝的可行性。该分析结论可以引导相似条件时设置弱单边贴角焊缝,以减少焊接量降低制造成本。

The weld joint between the plate-welded girder flange and web of heavy-load bridge crane bears complex stress,so proper design for the weld joint is important to ensure load-carrying safety.In view of the situation where 8-mm unilateral fillet welding which is much more less than domestic standard reference value is applied in the case of 5 1 mm-thick flange slab and 16mm-thick web of 800t bridge cranes,the stress distribution in weld joint is analyzed by the finite element modeling method to get the more accurate stress analysis result.The shell-shell submodel analysis is performed to verify the precision of grid density of the general model.Through shell-body submodel and contact analyses,precise research on grid refinement is done for the weld joints,which indicates feasibility of applying smaller fillet weld size for thicker flange plate and thinner web.The conclusion can facilitate to set the weak unilateral fillet flange weld under similar conditions to reduce the weld amount and production cost.