摘要
大跨度连续桥梁受长期荷载作用后的应力分布及承载能力会发生显著的变化,为准确评估多种因素(结构自重和使用荷载)对大跨度连续桥梁内部应力分布的影响,本文对长期荷载下的混凝土梁进行了挠度时程分析,基于长期变形试验总结了考虑长期荷载作用的梁性能变化规律,最后通过实测三跨连续桥梁的挠度和应力进行模型精准度验证。长期变形试验结果表明:正常使用荷载下的挠度随着混凝土强度等级的增大而降低,梁持荷180 d的极限承载力和挠度分别降低了12.0%、24.3%。
The stress distribution and bearing capacity of long-span continuous beam bridges under sustained load will change significantly.To accurately evaluate the influence of multiple factors(structural dead weight and service load)on the internal stress distribution of long-span continuous bridges.This paper analyzes the deflection time history of beams under sustained load,and summarizes the performance variation regular considering longterm load based on sustained deformation test.Finally,the accuracy of the model is verified by measuring the deflection and stress of the three-span continuous beam bridge.The results of sustained deformation test show that the deflection under normal load decreases with the increase of concrete strength grade,and the ultimate bearing capacity and deflection of the beam during 180 days under load decrease by 12.0%and 24.3%,respectively.
出处
《混凝土世界》
2024年第9期56-60,共5页
China Concrete
关键词
梁式试验
持荷性能
应力-应变关系
质量监测
Beam test
load carrying capacity
stress-strain relationship
quality monitoring
