Reinforcement Design of Three -Valves Towers and Effect Evaluation Based on Monitoring Data

Numerous three-valves towers for communication distributed around urban districts suffer from structural degradation during operation. The traditional methods using encased steel to strengthen the structure are not suitable for three-valves towers. To address this issue, a reinforcement method based on the combined section is proposed for improving the structural performance of three-valves towers. In this method, main bars are added at the side of the maximum stress axis of the original tower with multi-point hinge joints, which are also connected with the flange plate of the original tower by welding. After that, to evaluate the reinforcement effect precisely, the structural health monitoring (SHM) system for towers is established to obtain the data of horizontal displacement continuously before and after the reinforcement. Finally, the reinforcement of an actual three-valves tower is implemented using the method described above, with relatively low costs and a short period of construction. And the data acquired from the SHM system shows that the structural performance of this tower has been improved notably after the reinforcement.