连续钢桁梁桥节点板更换效果评价

在例行检查中发现沪昆线一下承式钢桁梁在中支承E8节点处节点板出现裂缝。为了分析节点板病害原因,对节点板进行面内面外变形测量,发现因结构本身尺寸发生变化对节点板产生附加内力,造成外侧节点板开裂。利用有限元软件对节点板进行计算,结果表明计算开裂位置与实际裂缝较为吻合。针对此种情况提出了更换节点板的方案,更换完成后对全桥进行了静载试验,重点对E8节点板进行了监测。试验结果表明更换后节点板参与结构作用的效果明显,能够满足列车正常运营的要求。

Evaluation on Replacement Effect of Gusset Plate in Continuous Steel Truss Bridge

It was found that cracks appeared in the gusset plate at the E8 joint of middle support of the through steel truss bridge on Shanghai-Kunming railway during routine inspection. In order to analyze the causes of the gusset plate defects,the in-plane and out-of-plane deformation measurements were carried out on the gusset plate. It was found that additional internal forces were produced on the gusset plate due to the change of the size of the structure itself,which resulted in the cracking of the outer gusset plate. The finite element softw are was used to calculate and analyze the gusset plate.The results show that the crack location is in good agreement with the actual location.In view of this situation,a scheme of replacing the gusset plate was proposed.After the replacement was completed,the static load test of the whole bridge was carried out,and the E8 joint of gusset plate was monitored emphatically. The test results show that the effect of gusset plate participating in structure is obvious after replacement,and it can meet the requirements of normal operation of train.