镇罗黄河特大桥钢栈桥与钻孔平台设计分析

Design and Analysis of Steel Trestle and Drilling Platform of Zhenluo Yellow River Bridge

栈桥可作为连接水上施工平台与陆地的车辆通行及材料运输的通道。该文以镇罗黄河特大桥为背景,基于工程简介和地质水文条件,针对工程特点和施工难点,分析设计标准及荷载要求、栈桥与钻孔平台设计特点和总体布置,采用Midas计算在450型旋挖钻位于栈桥支座处条件下栈桥与钻孔平台受力情况。研究表明,321贝雷梁的最大组合应力值达到293.2 MPa,距16Mn钢(Q345钢)的抗拉、抗压和抗弯强度设计值305 MPa已经很接近,且竖杆轴力最大值达到209.4 kN,距321贝雷片最大容许竖杆内力值210 kN也很接近。建议对支点处贝雷片腹杆进行补强处理,均采用工16a焊接或栓接连接。

The trestle bridge is used as a water construction platform to connect the vehicle traffic and material transportation channel on the land.This paper takes the Zhenluo Yellow River Bridge as the background and,based on the project introduction and geological and hydrological conditions,by aiming at the project characteristics and construction difficulties,analyzes the design standards and load requirements,the design characteristics of the trestle and the drilling platform,and the overall layout.The stress situation of the trestle bridge and the drilling platform under the condition that the excavation drill is located at the trestle support,the research shows that the maximum combined stress value of the 321 Bailey beam reaches 293.2 MPa,and the tensile,compressive and bending resistance of 16Mn steel(Q345 steel).The strength design value of 305 MPa is very close,and the maximum axial force of the vertical rod reaches 209.4 kN,which is also very close to the maximum allowable vertical rod internal force value of 210 kN for the 321 Bailey sheet.It is recommended to reinforce the beret web at the fulcrum,and the reinforcement measures are as follows the reinforcement structure consists of upper and lower chords and webs,and the construction is all connected by 16a welding or bolting.