Investigation of Structural Response of Reinforced Concrete Beams Strengthened with Anchored FRPs

Abstract

Abstract:The beneficial effect of a composite material anchorage system (CMAS) upon the ductility and load capacity of reinforced concrete (RC) beams strengthened either with glass (GFRP) or carbon (CFRP) fabrics was investigated. The anchorage system consisted of U-shaped GFRP or CFRP strip (U-strip) at end of FRP. The U-strips were bonded around the beam section and further anchored by two tufts of glass fibres, each of them embedded at the opposite beam face and specifically in the region of compression zone of the beam web. Experimental evaluations in simply supported lightly reinforced concrete (RC) beams strengthened with one GFRP or a CFRP sheet anchored at its ends by the composite anchorage have shown that their bending capacity has increased by 8% and 17%, respectively, in relation to the capacity attained in similar RC strengthened beams without anchorage. On the other hand, their ductility was improved by an amount of 94% and 37%, respectively. ANSYS finite element program was also used to numerically verify the response of strengthened RC beams obtained experimentally. The numerical results obtained are in good agreement with the experimental, thus, the calibrated model could now be used to extend the experimental results at lower cost.

Reliability and adaptability of the analytical models proposed for the FRP systems to the Steel Reinforced Polymer and Steel Reinforced Grout strengthening systems

“…(6) and (7) (9) where k is the reduction factor. A value of 0.75 is recommended for design purposes.…”

Study on Thermal Stress of Concrete Beams with Carbon-Fiber- Reinforced Polymers at Low Temperature

“…Specifically, studies have focused on the fire resistance [1][2][3][4], warm temperatures [5], freeze-thaw cycles [6], and other environmental conditions [7][8][9][10][11][12]. However, few studies have investigated the thermal stress induced in CFRP at low temperatures, which differs from that induced in freeze-thaw cycles.…”

“…Equations (8) and (9) can be substituted into equation (11) to obtain the stress caused by the temperature difference in a concrete beam reinforced by a prestressed CFRP sheet:…”

3D FE Analysis of RC Beams Externally Strengthened with SRG/SRP Systems

“…Amongst various methods developed for the strengthening and retrofitting of RC beams, the external bonding of Fiber Reinforced Polymer (FRP) composite materials has been widely accepted as an effective and convenient method [1][2][3]. Recent developments in the use of these strengthening systems have heightened the need to carry out reliable numerical analyses based on the Finite Element (FE) method capable of predicting the behavior of strengthened structural elements at all stages of loading up to failure.…”