Numerical Investigation on Dynamic Response of RC T-Beams Strengthened with CFRP under Impact Loading

Abstract

To precisely evaluate the retrofitting effectiveness of Carbon Fiber Reinforced Plastic (CFRP) sheets on the impact response of reinforced concrete (RC) T-beams, a non-linear finite element model was developed to simulate the structural response of T-beams with CFRP under impact loads. The numerical model was firstly verified by comparing the numerical simulation results with the experimental data, i.e., impact force, reaction force, and mid-span displacement. The strengthening effect of CFRP was analyzed from the section damage evaluation. Then the impact force, mid-span displacement, and failure mode of CFRP-strengthened RC T-beams were studied in comparison with those of un-strengthened T-beams. In addition, the influence of the impact resistance of T-beams strengthened with FRP was investigated in terms of CFRP strengthening mode, CFRP strengthening sizes, CFRP layers and FRP material types. The numerical simulation results indicate that the overall stiffness of the T-beams was improved significantly due to external CFRP strips. Compared with the un-strengthened beam, the maximum mid-span displacement of the CFRP-strengthened beam was reduced by 7.9%. Additionally, the sectional damage factors of the whole span of the CFRP-strengthened beam were reduced to less than 0.3, indicating that the impact resistance of the T-beams was effectively enhanced.

Numerical Assessment of the Impact Behavior of CFRP strengthened RC beams using different concrete models

“…Shell elements (S4R) were used for the simulation of the CFRP. The mechanical parameters of CFRP developed in this study are given in Table 2 [8,15,16]. Embedded region coupling was employed to describe the connection between longitudinal and transverse reinforcements in concrete.…”

Relationship between Structural Stiffness and Viscous Damping Coefficient in Reinforced Carbon Structure under Varying Carbon Fiber Angles

“…Several manufacturing processes have been studied, such as the effect of laser fabrication [4] and ultrathin electrospun nanofibers on multifunctional fiber-reinforced polymer composites [5]. Various applications of CFRP materials, including in the production of concrete columns [6], Tshaped beams [7], and Belleville springs [8] have been studied. Case studies have revealed the advantage of the reinforced composite structure in diverse industrial applications and the structure is expected to contribute to an emerging market for CFRP materials.…”

Numerical Study of Concrete

“…This is due to the existence of a reasonable pore structure. Zhao et al [5] used the finite element method for modeling the fundamental behavior of T-beams with carbon fiber-reinforced plastic under impact loads. The results show that the overall stiffness of the T-beams was significantly improved due to the carbon fiber-reinforced plastic strips.…”