摘要
针对活载与恒载比值高的情况,提出了梁中预应力随活载变化而变化的智能控制方法,即根据梁承受的荷载情况,在梁中配置适当的智能锚具,通过智能锚具的顶升、回缩改变梁中的预应力大小,从而实现梁监控点处的挠度或应变始终被控制在目标范围内。基于开关控制算法,采用模拟信号控制系统进行了智能预应力简支梁在缓慢移动荷载作用下的挠度控制试验,采用数字信号控制系统进行了智能预应力斜拉桥在缓慢移动荷载作用下的应变控制试验。试验结果验证了控制思想的可行性,同时为快速移动荷载下的智能控制提供试验基础。
Based on the high ratio of live load to dead load,this paper proposes a smart prestressed beam,which can change the value of prestress under different live loads.According to the live load on the beam,the deformation and strain of the smart prestressed beam can be controlled in the design range if the beam is collocated with suitable telescopic mechanisms,which can change the value of prestress in the smart beam by means of propping up or drawing back telescopic mechanisms.The deformation of a steel beam model,which uses analog signals control system and regards mid-span deformation as its control target,is analyzed to show the whole function course of prestress in the beam under three typical locomotive loads.Simultaneously the strain of a cable-stayed bridge model,which uses digital signals control system and regards mid-span strain as its control target,is also introduced.The result of experiments validated the feasibility of smart prestressing control theory.
出处
《工程力学》
EI
CSCD
北大核心
2011年第5期105-110,共6页
Engineering Mechanics
基金
国家自然科学基金项目(50378015)
国家教育部博士点基金项目(20090092120018)
江苏省基础研究计划项目(BK2008313)
东南大学科技基金项目(KJ2010403)
关键词
智能结构
主动控制
智能预应力
模型试验
开关控制
smart structure
active control
smart prestressing
model experiment
switch control
