壓電智能骨材於結構損傷評估之應用

Application of Piezoceramic-Based Smart Aggregates to Health Monitoring of Structures

陳星宇(Xing-Yu Chen)

指導教授 ： 廖文義

國立臺北科技大學/工程學院/土木與防災研究所/碩士(2009年)

https://doi.org/10.6841/NTUT.2009.00010

摘要

本論文之主要研究方向為運用壓電材料進行混凝土早期強度評估及結構健康診斷，研究所使用之智能骨材為以壓電材陶瓷料所製成，利用基本波動力學及智能材料可發射應力波，亦可接收應力波的特性，進行混凝土結構早期強評估與健康診斷之研究，結構健康診斷為將智能骨材埋入RC結構內，當試體受到破壞時，由智能材料發射應力波及由不同位置的智能骨材擷取應力波，利用應力波振幅隨著結構破壞程度、裂縫增加而減少特性，可知結構損壞程度，再利用數值分析得到損壞指標，在早期強度評估方面為利用訊號振幅隨著抗壓強度增強而減少之特性，藉由不同天數之抗壓強度及定時測量智能骨材的訊號振幅，知振幅會隨抗壓強度上升而減弱，故可知抗壓強度及訊號振幅之間的關係。

關鍵字

健康診斷 ； 智能骨材 ； 早期強度評估 ； 混凝土 ； 壓電陶瓷

並列摘要

Recent years, piezoelectric materials have been successfully applied to the early-age strength monitoring and damage detection of concrete structures due to their advantages of active sensing, low cost, quick response, availability in different shapes, and simplicity for implementation. The adopted smart aggregate of this research is fabricated by embedding a water-proof coated piezoceramic patch into a small concrete block. The major purposes of this research are (1) Development of the technique for early-age strength monitoring of concrete (2) Health monitoring of concrete structures under static load and seismic load. The early-age strength monitoring of concrete is performed by monitoring the harmonic response amplitude of smart aggregates. Experimental results show that the predicted concrete strength matches the experimental results obtained in the compressive test. Tests of health monitoring are the simple bending test of concrete beams, RC columns subjected to reversed cyclic loading, shake table test of a RC column. By analyzing the wave response, the existence of crack can be detected and the severity can be estimated. A damage index is developed to evaluate the damage status of the structures. The experimental results demonstrate the sensitiveness and the effectiveness of the proposed piezoceramic-based approach in the structural health monitoring of the concrete structure under static and earthquake loading. The multi-purpose smart aggregate has the potential to be implemented to the comprehensive performance evaluation of concrete civil structures.

並列關鍵字

structural health monitoring ； smart aggregate

參考文獻

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