RC床版の健全度モニタリング手法に関する振動発電デバイスの利用

抄録

Micro Energy Harvester (MEH) based on micro-electro-mechanical systems (MEMS) provides a green and virtually infinite alternative energy source to traditional energy sources. The electrostatic vibratory power generator outputs electric power under vibrating environmental accelerations, where a certain amount of energy also can be generated by vibration of civil infrastructures due to such as natural condition and traffic loading. MEH is a self-powered small device which can be easily installed into existing structures as an accelerometer measuring the vibration with power generation data referred to frequency alteration. In this study, innovative monitoring technology system utilizing MEH device network is proposed for detecting damage in concrete structure and inspection of deterioration in RC (Reinforced Concrete) slab. Damaged structures are simulated in FEM analysis of vibrational behavior for differently deteriorated models with reduction of Young’s modulus of concrete. According to the FEM analysis results, power generation by MEH is computed based on resonance frequency of structure and amplitude at each position of installed MEHs. Potentials of power generation at each MEH are variable since resonance frequency of the targeted structures is decreased when they are even partly deteriorated while amplitude at damaged part is locally increased. It is shown that power generation indices, which are newly introduced according to structural vibration mode, enable to detect and identify the most deteriorated area and deterioration progress in RC slab. Utilizing Electrostatic vibration based MEH, MEMS sensor network can work for infrastructure monitoring system.