横向预应力加固空心板梁有效预应力监测及分析

Monitoring and Analysis of Effective Prestress of Hollow Slab Beams Reinforced by Transverse Prestress

针对旧桥因不同程度裂缝等因素导致梁体承载能力不足的问题,依托采用了横桥向体外预应力加固方法的某工程实例,通过测点布设并安装无源磁电振动传感器采集数据,运用以云平台终端为核心的多性能监测系统,基于FFT原理与振动频率法分析多孔道预应力索索力衰减规律。研究结果表明,预应力索索力存在衰减,但整体衰减程度较小,桥梁呈现出中部孔道预应力索衰减程度相对较高而向两侧逐级递减的规律。

In view of the insufficient bearing capacity of beams of old bridges due to different degrees of cracks and other factors,relying on a project example of external prestressing reinforcement method of cross bridges,passive magnetoelectric vibration sensors are deployed and installed at measuring points to collect data,and a multi-performance monitoring system based on the cloud platform terminal as the core is adopted.The attenuation law of multi-channel prestressed cable force is analyzed.The results show that the prestressed cable force attenuates,but the overall attenuation degree is small.The attenuation degree of the prestressed cable in the middle channel of the bridge is relatively high and gradually decreases to both sides.