Using Steel Fiber‐Reinforced Concrete Precast Panels for Strengthening in Shear of Beams: An Experimental and Analytical Investigation

Abstract

In this paper, the performances of reinforced concrete (RC) beams strengthened in shear with steel fiber-reinforced concrete (SFRC) panels are investigated through experiment, analytical computation, and numerical analysis. An experimental program of RC beams strengthened by using SFRC panels, which were attached to both sides of the beams, is carried out to investigate the effects of fiber volume fraction, connection type, and number and diameter of bolts on the structural responses of the retrofitted beams. The current shear resisting model is also employed to discuss the test data considering shear contribution of SFRC panels. The experimental results indicate that the shear effectiveness of the beams strengthened by using SFRC panels is significantly improved. A three-dimensional (3D) nonlinear finite element (FE) analysis adopting ABAQUS is also conducted to simulate the beams strengthened in shear with SFRC panels. The investigation reveals the good agreement between the experimental and analytical results in terms of the mechanical behaviors. To complement the analytical study, a parametric study is performed to further evaluate the influences of panel thickness, compressive strength of SFRC, and bolt pattern on the performances of the beams. Based on the numerical and experimental analysis, a shear resisting model incorporating the simple formulation of average tensile strength perpendicular to the diagonal crack of the strengthened SFRC panels is proposed with the acceptable accuracy for predicting the shear contribution of the SFRC system under various effects.

Structural Strengthening/Repair of Reinforced Concrete (RC) Beams by Different Fiber-Reinforced Cementitious Materials - A State-of-the-Art Review

“…The findings present that the shear behavior of the beams strengthened by SFRC panels was remarkably enhanced. In addition, nonlinear finite element analysis also found strong agreement with the experiments [22]. Besides the experimental studies, several researchers have conducted the finite element method (FEM) to simulate the structural elements in recent FEM software.…”

“…In addition, a high number of cracks were visible for the beams strengthened by concrete without steel fiber due to lower tensile strength of the mortar without fibers and number of the cracks has been decreased with the increase of volume fraction of steel fibers because the fibers make bridges in the strengthening materials. Furthermore, inserting bolts and increasing their numbers help the shear force to get transfer to the panels and also prevent the debonding of the panels, while the diameter of bolts has no significant effect on the crack pattern [22].…”

Mechanical and Environmental Proprieties of UHP-FRCC Panels Bonded to Existing Concrete Beams

“…For these reasons, some studies have been devoted to the mechanical performance of precast HP-FRCC slabs [12] used for strengthening RC structures. For instance, Jongvivatsakul et al significantly increased the shear capacity of RC beams when Steel Fiber-Reinforced Precast Panels are applied on the faces [13].…”

Effect of Modified Deformed Steel Fiber on Mechanical Properties of Artificial Granite

“…Many scholars have done a lot of research on steel fiber and added steel fiber to the matrix to enhance the matrix strength [18][19][20][21][22][23][24][25][26][27][28][29]. Under external loading, steel fiber can effectively prevent the formation and expansion of cracks in artificial granite matrix.…”