摘要
为准确计算桥梁体外预应力加固锚固区应力,指导锚固区配筋设计,以一座4跨预应力混凝土连续刚构桥为背景,提出一种基于实际损伤的体外预应力加固锚固区应力分析与配筋设计方法。首先根据连续刚构桥下挠计算参数敏感性分析结果,确定计算参数组合,建立锚固区局部分析有限元模型;然后基于容许应力法对锚固区进行应力分析;最后对锚固区三向应力较大区域进行配筋设计。以3座桥梁为算例计算锚固区配筋量,并与基于全桥有限元法的实桥配筋结果进行对比,结果表明:采用该方法计算的锚固区横桥向、竖向和单锚局部承压区配筋量与采用全桥有限元法计算的配筋结果基本接近。该方法考虑了加固前原结构的损伤,对于非规则、异形锚固构造也具有适用性,同时避免了冗繁的全桥有限元建模与计算过程。
This paper analyzes the stresses in the anchorage zone of external prestressing tendons implemented to retrofit damaged bridges and presents a prestressing tendons design method.A four-span prestressed concrete continuous rigid-frame bridge is used for a case study.Firstly,in accordance with the deflection calculations and parametric sensitivity analysis of the continuous rigid frame bridge,the parameter combinations in calculation were determined,and the numerical model of the anchorage zone was developed.Secondly,stresses in the anchorage zone were analyzed using allowable stress method.At last,prestressing tendons in the area with relatively great three-directional stress in the anchorage zone are designed.Based on three case bridges,the amount of prestressing tendons in the anchorage zone is calculated and compared with the amount calculated by the finite element model of the overall bridge.The results demonstrate that the transverse and longitudinal prestressing tendons as well as the prestressing tendons in the local load bearing area of a single anchorage approximate the amounts calculated by the finite element model of the overall bridge.The method takes into account the damages of the original structure and is applicable to the irregular anchorages,while avoiding the tedious full-bridge numerical simulation and calculation.
作者
胡营
李淑明
骆佐龙
王美霞
HU Ying;LI Shuming;LUO Zuolong;WANG Meixia(Zhonglu Qiming Transportation Technology Co.,Ltd.,Taiyuan 030031,China;Zhongyu Tiexin Transportation Technology Co.,Ltd.,Hengshui 053020,China;School of Electric Power,Civil Engineering and Architecture,Shanxi University,Taiyuan 030031,China;RoadMainT Co.,Ltd.,Beijing 100095,China)
出处
《世界桥梁》
北大核心
2024年第1期110-116,共7页
World Bridges
基金
山西省自然科学基金面上项目(202203021221025)
山西省高等学校科技创新项目(2021L010)
中央高校基本科研业务费专项项目(300102213522)。
关键词
桥梁工程
损伤
体外预应力加固
锚固区
应力
容许应力法
配筋设计
bridge engineering
damage
external prestressing tendon retrofit
anchorage zone
stress
allowable stress method
prestressing tendons design
