Issue 54

F. Benaoum et al, Frattura ed Integrità Strutturale, 54 (2020) 282-296; DOI: 10.3221/IGF-ESIS.54.20

G EOMETRICAL MODEL AND MATERIAL PROPERTIES OF REINFORCED CONCRETE (RC)

I

n this part, we are interested in the study of the efficiency of the adding of conventional steel bars in a concrete beam under three-point bending load. The concrete beam and supports were modeled as volumes. The dimensions and combined volumes of the support and beam are shown in Fig. 7a. A reinforced concrete beam is a 750 mm in length with cross section of 150 mm x 100 mm (depth x width) and a span of 700 mm is considered in this study. This beam is made of 10 mm diameter steel bars and they used as the main tensile bars and of 6 mm diameter steel stirrups at 120 mm spacing.

F 

2 Φ 8 mm bars

Φ 6mm stirrups

150

120 mm

2 Φ 10 mm bars

100

730 mm

Ds

(a)

V f = 50%

V f = 0%

V f = 100% of CFRP

V f = 50%

V f = 0%

V f = 100%

V f = 100%

V f = 0% of CFRP

Type D

Type C

Type B (0%-100%)

(100%-0%) Type A

(50%-100%)

(50%-0%)

Carbon Fibers

(c)

Adhisive sv

(b)

Figure 7: (a) Details of beam specimens, (b) Details of RC beams reinforced by FRPs plate, (c) Mesh of the concrete and reinforcement configuration. In addition, a numerical analysis of the previously RC beams reinforced by FRPs plate were highlighted. Fig. 7b presents a representative diagram of the different steps related to the transition from the reference beams (witness beam) to the rehabilitated beams (type A, B, C and D). The Solid65 element was used to model the concrete beam and Link8 elements were used to create the flexural and shear reinforcement. Reinforcement exists through the length of beam. Shear stirrups are modeled on a section normal to the length of the concrete beam. The finite element mesh for the reinforced concrete (RC) beam is shown in Fig. 7.c. In order to study the effect of reinforcing and its relative percentage value in concrete on the load-deflection response of concrete, the same dimensions and mechanical properties as those used by several authors [10, 39-40] were considered in this analysis and are given in Tab. 2.

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