Strengthening of reinforced concrete beams using ultra high performance fibre reinforced concrete (UHPFRC)

Abstract

In this study the efficiency of the use of Ultra High Performance Fibre Reinforced Concrete (UHPFRC) for the strengthening of existing Reinforced Concrete (RC) beams has been investigated. Experimental work has been conducted to determine UHPFRC material properties. Dog-bone shaped specimens have been tested under direct tensile loading, and standard cubes have been tested in compression. These results have been used for the development of a numerical model using Finite Element Method. The reliability of the numerical model has been validated using further experimental results of UHPFRC layers tested under flexural loading. Further numerical study has been conducted on full-scale beams strengthened with UHPFRC layers and jackets, and these results were compared to respective results of beams strengthened with conventional RC layers and with combination of UHPFRC and steel reinforcing bars. Superior performance was observed for strengthened beams with UHPFRC three side jackets, and the efficiency of this technique was highlighted by comparisons with other strengthening techniques.

Exploitation of Ultrahigh‐Performance Fibre‐Reinforced Concrete for the Strengthening of Concrete Structural Members

“…However, applying the sandblasting technique on the parent concrete surface before strengthening gives the highest strength. Figure 4: E ect of strengthening con guration on (a) exural capacity [13] and (b) shear capacity [24]. (4) e behaviour of the strengthened member depends on the strengthening con guration.…”

“…e results indicated that using UHPFRC, as repaired materials for the predamaged RC beams, would result in a significant increase in the failure load. Lampropoulos et al [13] demonstrated that using a layer of UHPFRC at different locations, as strengthened materials of RC beams, could increase the ultimate flexural strength of all of the strengthened beams. Mohammed et al [3] tested many RC beam specimens strengthened with UHPFRC under torsional loading.…”

“…e following recommendations are suggested for better understanding of the potential of UHPFRC in repairing and strengthening, as well as the behaviours of the Figure 9: E ect of steel bre content on (a) exural capacity and sti ness of strengthened RC beams [13,23,27] and (b) shear capacity [39]. …”

Numerical Assessment of Ultra-high Performance Concrete Material

“…Brühwiler and Denarie [5] carried out four applications of UHPC for the protection of crash barrier wall, strengthening of highway bridge, bridge piers, and industrial slabs. Later, the studies on UHPC strengthening RC members have been conducted extensively [6][7][8]. The results showed that UHPC enhanced overall response of structures.…”

“…There are several studies on mechanical properties of UHPC and its strengthening applications [5][6][7][8]. Brühwiler and Denarie [5] carried out four applications of UHPC for the protection of crash barrier wall, strengthening of highway bridge, bridge piers, and industrial slabs.…”