走锚漂流船舶撞击下桥墩基桩损伤分析

Damage analysis of foundation pile of bridge pier under collision of drifting ship after dragging anchor

某挖沙船因洪水冲击走锚漂流,与下游浔江特大桥非航道孔桥墩发生碰撞。通过对事故时水文气象、漂流船舶状态与受损状况、受损桥墩外观调查,采用超声对测法和反射波法分别检测了撞击区域桥墩混凝土内部损伤和桩基桩身完好性,基于ABAQUS有限元软件分析了走锚漂流船舶作用下桥墩桩身应力、位移和损伤分布,综合分析判断事故中桥墩的损伤状况,为事故的后续处理提供技术依据。结果表明:桥墩碰撞处无开裂和明显破损,桥墩桩与盖梁间连接完好,上部结构与桥墩间搁置正常;碰撞区域混凝土内部无明显损伤,受撞桥墩桩身结构完整无明显缺陷;高危损伤区域为变径处系梁的左上和右下连接处;船舶走锚与船舶漂流对桥墩的撞击作用效应差别巨大,可判定本次碰撞事故未对受撞桥墩结构造成损伤。

A dredging ship was drifted by flood after dragging the anchor and collided with the bridge pier of the nonnavigation hole of the Xunjiang Grand Bridge.According to the investigation of the hydrometeorological conditions,the drifting ship state,the damage status of the accident and the exterior appearance of the damaged bridge pier,the ultrasonic opposite measurement method and the reflected wave method were used to detect the internal damage of the impact area of the concrete bridge pier and the integrity of the pile foundation,and ABAQUS was used to calculate the stress,displacement and damage distribution of the bridge pier under the action of the impact of the drifting ship after dragging anchor to analyze and judge the damage status of the bridge pier in the accident,which provides a technical basis for the subsequent processing.The results show that there was no cracking and obvious damage at the collision of the pier,the connection between the pier and the cover beam was intact,and the upper structure was normally shelved on the pier.There was no obvious damage inside the concrete in the collision area,and the structure of the pile body was intact without obvious defects.High-risk damage existed at the upper left and lower right joints of the beam at the variable diameter area.There was a huge difference between the impact of ship anchoring and ship drifting on the pier,and it can be concluded that the collision did not cause damage to the structure of the pier.