The flexural rehabilitation of reinforced concrete beams by the use of prestressed advanced composite plates

An Experimental Investigation on Flexural Behavior of Reinforced Concrete Beams Strengthened by an Intelligent CFRP Plate with Built-In Optical Fiber Bragg Grating Sensors

“…Up to date, there are no recommendations on the anchorage set of wedge-type anchorages in the current specifications [30][31][32]. Thus, according to this calculation, it 8 Journal of Sensors is necessary to recommend using 0.8 mm as an initial anchorage set since a certain degree of safe redundancy is taken into account. As shown in Figures 11(a) and 11(b), some significant recommendations are made: (1) the CFRP strain increased linearly with the tension load at the prestressed tension stage, and the measured data of the FBG sensor embedded in the CFRP plate is highly consistent with that of the strain gauge, which is also reflected in the process of short-term prestress loss stage; (2) the prestress loss mainly occurs during the first 30 min after prestress force transferring to the anchorage system and the strain of the CFRP plate decreases slightly in the following testing period (about 24 hours).…”

“…The idea of posttensioned CFRP strips with mechanical anchors for the strengthening of RC beams under bending began also at EMPA in the early 1990s as part of a Ph.D. thesis [7]. In the following three decades, the use of externally bonded posttensioned FRP plates to reinforced concrete (RC) structures for structural flexural reinforcement is widely deployed as a practice, and extensive experimental and theoretical researches have been conducted on the failure modes and mechanical properties of the posttensioned CFRP plate-strengthened RC flexural members and structures [8][9][10][11][12][13][14][15][16][17][18][19][20][21][22][23][24]. Posttensioned FRP reinforcement enables the stress in the internal reinforcing steel and deflections will decrease, the crack widths reduced, both the serviceability and the durability of a structure in addition, the material to become more efficient since a greater portion of its tensile capacity is employed.…”

Ocena Nośności Doraźnej Belek Stalowych Wzmocnionych Naprężonymi Taśmami CFRP

“…Efektywność wzmocnienia oraz wykorzystanie kompozytu można zwiększyć poprzez wstępne naprężenie taśm. Tezę te potwierdzają liczne badania przeprowadzone na elementach żelbeto-wych [4], [6]. Jak dotąd zastosowanie wstępnie naprężanych taśm do wzmacniania belek stalowych zostało zbadane w ograniczonym zakresie [7].…”

Suggestion of flexural capacity evaluation and prediction of prestressed CFRP strengthened design

“…In particular, active research is being conducted on strengthening methods using FRP plates as an alternative to steel plate attachment [1]. There have been numerous researches on FRP sheet attachment and this method has been applied extensively to bridge girders and building slabs [2][3][4][5][6].…”