近年來,國內外土木工程界於鋼筋混凝土結構修復補強實務中,較常選用之黏接修補材料多以環氧樹脂為主。環氧樹脂良好的黏著性能早已受到證實,但其屬於有機物質材料,不耐高溫的性能卻始終是一項隱憂。前期之研究已多方面探討了一種新開發之「無機聚合樹脂」材料取代環氧樹脂的可行性,強度試驗方面包括混凝土圓柱試體與鋼筋混凝土矩形梁包覆CFRP及GFRP之補強研究,耐高溫試驗方面包括混凝土圓柱試體包覆CFRP及GFRP之耐高溫性能研 究,結果証實的確可發揮相當的補強效果,而其耐高溫方面之性能則遠超過環氧樹脂。 本研究則嘗試以「無機聚合樹脂」替代環氧樹脂作為膠接材料,進行鋼筋混凝土梁包覆FRP補強之耐高溫性能實驗研究,探討剪力補強在高溫後之補強效能。實驗參數包括五種溫度環境(常溫、100℃、250℃、600℃、710℃)、兩種FRP包覆材料(CFRP及GFRP)及兩種包覆層數(一層及兩層)。結果顯示應用無機聚合樹脂包覆FRP鋼筋混凝土梁剪力補強之成效,於常溫下稍低於使用環氧樹脂,而在高溫狀態下,應用無機聚合樹脂者則仍然能維持一定程度之補強效益,因此,在實務上應有發展的空間。
Recently, in the practical structural retrofit, the good adhesive effect of epoxy has been confirmed. Nevertheless, its poor heat resistant property remains a lurking danger. Preceding works have studied the possibility replacing epoxy by inorganic material, namely geoplymer. A series of experiment, including the strength of concrete cylinders and RC beams covered by CFRP and GFRP using geopolymer. And followed by heating resistant experiments, for concrete cylinders confined by CFRP and GFRP using geopolymer. It is found that the results were encouraging. In the present study, it is attempted to a step forward. The effect of shear strengthening of reinforced concrete beams with FRP jacket using geopolymer as bond material after high temperature was investigated. The parameters of the experiments included five different temperatures, i.e. room temperature, 100℃, 250℃, 600℃and710℃, two kinds of FRP jacket material, namely CFRP and GFRP, and two different layers. The results show that under room temperature, the overall shear strengthening effect of the beams is lower than those of using epoxy. However, in all cases the common requirements of shear strengthening are considerably fulfilled. On the other hand, it is worth noting that the strengthening effect still maintained to certain grade under high-temperature for the cases of using geopolymer.