基于一阶优化法的连续梁桥整体顶升顶升力优化  

Optimization of the Overall Jacking Force of Continuous Girder Bridge Based on First-order Optimization Method

作　　者：张鸣祥[1,2] 张睿 钟其仁[1] ZHANG Mingxiang;ZHANG Rui;ZHONG Qiren(School of Civil and Hydraulic Engineering,Hefei University of Technology,Hefei 230009,China;Anhui Civil Engineering Research Center for Disaster Prevention and Mitigation,Hefei 230009,China)

机构地区：[1]合肥工业大学土木与水利工程学院,安徽合肥230009 [2]土木工程防灾减灾安徽省工程技术研究中心,安徽合肥230009

出　　处：《安徽建筑大学学报》2023年第5期10-17,67,共9页Journal of Anhui Jianzhu University

基　　金：国家自然科学基金项目(51878234)。

摘　　要：桥梁顶升施工过程中,千斤顶的作用位置受工程实际情况的约束。为在有限区域布置的情况下确定千斤顶的顶升力,提出了一种基于一阶优化法的合理顶升力计算方法。该方法将复杂的力学问题转化为目标函数的求解问题,即通过建立有限元模型获得梁桥上部结构的内力值和应力值,再通过MATLAB程序进行优化分析。为验证该方法的有效性,以单箱单室(双室)预应力混凝土连续梁桥为背景,采用该方法计算千斤顶合理顶升力。基于连续梁桥受力特点,以顶升状态和成桥状态下的梁体弯矩近似相同为目标,以千斤顶顶升力和布置位置为优化变量,以《公路钢筋混凝土及预应力混凝土桥涵设计规范》对短暂状况构件的应力规定为约束条件,建立了目标函数进行顶升力优化。结果表明,该优化方法能解决千斤顶刚性约束方式无法解决的支座出现负反力的问题;千斤顶的作用位置可作为自变量参与优化。The placement of jacks during bridge jacking construction is limited by the working conditions.To determine the jacking force in the case of a limited area,a jacking force calculation method based on the first-order optimization method is proposed.The method transforms complex mechanical problems into the solution of the objective function,obtaining the internal force and stress of the beam bridge superstructure based on finite element modeling,and then carrying on optimization analysis through MATLAB program.To verify the effectiveness of this method,the reasonable jacking force is calculated in the case of single-and double-chamber of singlebox prestressed concrete continuous girder bridges.Considering the force characteristics of continuous girder bridges,the objective function is established to optimize the jacking force by taking the approximation of girder bending moments in jacked and bridge-forming states as an objective,jacking force and deployment position as optimization variables,and stress provisions for transient condition members in Specifications for Design of Highway Reinforced Concrete and Prestressed Concrete Bridges and Culverts as constraints.The results show that the method can solve the problem of negative reaction forces on bearings that cannot be solved by the rigid constraint method of the jack and the position of the jack can be an independent variable in the optimization.

关 键 词：桥梁顶升施工 连续梁桥 目标函数 一阶优化法 顶升力 

分 类 号：U441.2[建筑科学—桥梁与隧道工程]