滨北桥钢板及焊接接头质量标准研究

滨北线松花江公铁两用钢桁梁桥处严寒地区哈尔滨,设计最低温度为-43.1℃时,桥梁用结构钢Q370q E、Q420q E的各项力学性能指标在规范中没有规定,因此有必要开展钢板及焊接接头质量标准研究。根据断裂力学原理,以防断裂设计即结构材料所具有的断裂抗力Kc必须高于结构物所要求的最高断裂驱动力KI(KC≥KI)为理论依据,通过试验数据确定采用Q370q E、Q420q E高强度结构钢作为滨北桥的结构用钢,得出钢板焊缝的强度、韧性以及钢板的断裂抗力、焊缝冲击功等指标的设计限值及板厚与温度的变化关系,为确保滨北桥钢板及焊接接头技术指标的要求,提出焊缝的韧性与钢材强度的韧性相匹配原则。

Quality Standard for Steel Plate and Welded Joints of Bin-Bei Bridge

Songhua River Bridge on Harbin- Beijing line is a combined bridge located in Harbin. The minimum tolerant temperature of the bridge is- 43. 1 ℃. As the mechanical performances of the high-tensile structural steel( Q370 q E and Q420 q E) applied to the major structure of the bridge have not been specified in relevant specifications,it is necessary to conduct researches on the standard for the steel plate and welded joint. Based on fracture mechanics theory,the break tolerance of steel( KC) must be greater than the maximum break driving force KI( KC≥ KI). The test results show that Q370 q E and Q420 q E are suitable for Songhua River Bridge. The welding strength of steel,the impact toughness of steel,the relationship between the thickness of steel and the temperature area obtained. Moreover,the principle that governs the toughness of weld joint to match the toughness of steel is introduced.