斜拉索是斜拉橋的一個重要組成部分,是斜拉橋的主要承載部件。斜拉橋橋跨結構的質量和橋上活載絕大部分或全部通過斜拉索傳遞到索塔上。實時監測分布于大橋上的橋索張力變化,對于了解斜拉橋的健康狀態,確保斜拉橋的安全是至關重要的。聚偏二氟乙烯(polyvinylidene fluoride) 傳感器通過監測應變得到拉索的振動信號,采用數字信號處理芯片實現振動信號的快速傅立葉變換,利用變換得到的振動頻率計算出拉索的張力,實現斜拉索張力的在線測量。將橋索張力的變化輸入到神經網絡中進行斜拉橋損傷識別,取得了良好的實驗結果。
關鍵詞: 聚偏二氟乙烯; 斜拉橋; 橋索引力在線監測
Abstract : The stayed cable of cable2stayed bridges is the main load2bearing components. Most of the load is transfer to the tower of the bridge. Through monitoring the cable tension and its variation , the overall technical condition to a cable2stayed bridge can be estimated and assure the safety of the bridge. Polyvinylidene fluoride is applied as sensor to monitoring the vibration of stayed cables ,and digital signal processor is applied to realize the FFT transform of signal ,the tension can be calculated. The tension of stayed2cable is imputed to neural network to realized damage recognition of cable2stayed bridges. The experimental result shows that the damage recognition method is efficient .
Key words : polyvinylidene fluoride(PVDF) ; cable2stayed bridge ; on line measurement of cable tension