孫傳智+喬燕+王振波+左工



摘要:為了研究高延性聚酯纖維加固鋼筋混凝土柱的抗震性能,共進行了7根柱的低周反復試驗,其中,3根在未加固狀態下進行試驗,4根柱粘貼高延性聚酯纖維加固后進行試驗,針對位移延性系數、等效粘滯阻尼系數、總耗能、承載力和纖維帶的應變進行了研究與分析。研究結果表明:未加固柱的承載力、耗能能力和延性都比較低,采用高延性聚酯纖維加固后的試件裂縫發展緩慢,加固后柱的承載能力、耗能能力、延性均有不同程度地提高;在塑性鉸區域內增加局部配筋,能夠提高纖維布的約束效果。
關鍵詞:聚酯纖維;鋼筋混凝土柱;加固;抗震性能
中圖分類號:TU375.1文獻標志碼:A文章編號:16744764(2017)03008309
Abstract:Seven RC columns were tested under cyclic lateral load and constant axial load to study the seismic behavior of reinforced concrete column strengthened with high ductility polyester fiber. Three unreinforced columns were tested, and four other columns were tested after strengthened with high ductility polyester fiber sheets. The bearing capacity of three unreinforced columns was low. And the energy dissipation capacity and ductility were also relatively low. The cracks of reinforced specimen appeared relatively late and the cracks developed slowly. The strength, ductility and energy dissipating capacity of the retrofitted columns were improved at different degrees. And the ductility increase was more obvious. The efficiency of the use of fiber cloth can be improved through adopting the measures of improving the reinforcement ratio the plastic hinge region and adopting the measures of improving the length of longitudinal reinforcement, and the seismic behavior of RC column strengthened with high ductility polyester fiber increased.
Keywords:polyester fiber; reinforced concrete column; strengthen; seismic behavior
中國《建筑抗震設計規范》(GB 50011—2010)在強度設計的同時還引入了延性設計概念。延性差的結構,后期變形能力差,從而導致結構發生脆性破壞。因此,在抗震加固設計中,應該保證結構具有較大變形能力,在地震作用下吸收較多能量,而不發生倒塌破壞。目前,在結構抗震加固領域,常見的纖維增強復合材料(包括碳纖維、玻璃纖維、芳綸纖維)由于重量輕、抗拉強度高、耐久性好和易于施工等優點,得到了廣泛應用[15]。但是,一個值得注意的問題是:FRP材料,特別是碳纖維,直到破壞都基本表現為線彈性,延伸率較小,從而導致約束混凝土產生脆性破壞[1]。
高延性聚酯纖維加固是一種利用聚氨基甲酸酯膠粘貼高延性聚酯增強材料(High Ductility Polyester Fiber,簡稱HDPF)的加固技術[6] 。學者Kabeyasawa等[79] 、Kim等[10]、Kono等[11]利用該技術進行了加固混凝土剪力墻和框架了研究。……