连续栓焊钢桁梁桥评定与加固一体化方法探讨

20世纪70年代，我国开始建造连续栓焊钢桁梁桥，由于设计荷载等级较低，已不能满足当前迅猛增长的荷载要求，同时频繁的超载使得该类桥梁出现了较为严重的病害。本文以某公路桥为例。探讨了一套完整的适用于钢桁梁桥的评定加固一体化方法。首先通过病害调查找出钢桁梁的各种病害，结合实桥测试结果建立并修正ANSYS三维分析模型，通过对疲劳、结构承栽能力以及构造的综合分析，对通行汽-20标准荷载下的桥梁技术状态进行评定。然后依据评定结果进行加固设计，通过比较。最终加固方案确定为焊接法加固节点板和拉杆，栓接法加固压杆，修补并加强桥道纵梁，设置剪力钉并重新现浇连续桥面板。

Discussion on Assessment-strengthening Integrity of a Welding-bolted Continuous Truss

Welding-bolted continuous truss bridges constructed in 70s can not safely carry the present traffic load which increased explosively during several decades. Due to the lower design load-rate, this kind of bridge has been tortured by overload so frequently that serious defects are emerging. Based on an example of a welding-bolted continuous truss bridge, a method of assessment-strengthening integrity is discussed. The defects investigation is first conducted. With in-situ test data, a 3 - D FE mechanical model with ANSYS is then established and calibrated. Fatigue life, load carrying capacity and deformation of the truss are analyzed, and the assessment under the Q - 20 load rate is analysed. Finally, the strengthening plan is developed according to the assessment.