Composite action of pre-cracked reinforced concrete beams repaired with adhesive bonded steel plates
- Authors: Ngidi, Sandile D. , Dundu, Morgan
- Date: 2018
- Subjects: Flexural strength , Pre-cracked reinforced concrete beams , Repairing
- Language: English
- Type: Article
- Identifier: http://hdl.handle.net/10210/270588 , uj:28764 , Citation: Ngidi, S.D. & Dundu, M. 2018. Composite action of pre-cracked reinforced concrete beams repaired with adhesive bonded steel plates.
- Description: Abstract: Previous studies demonstrated that significantly cracked beams can be repaired by bonding steel plates, however, there is a lack of comprehensive information about the effect of the width-to-thickness ratio of steel plates on repaired composite beams, and the use of thicker plates to repair failed RC beams. This paper presents an assessment of the performance of precracked reinforced concrete beams repaired with adhesive bonded steel plates, of varying width-to-thickness ratio, at the soffit. A total number of 12 beams were tested under a twopoint static loading. Group 1 consisted of two control specimens, Group 2 comprised of five beams that were pre-cracked to 60% (serviceability load), and Group 3 consisted of another five beams that were pre-cracked to 85% of the ultimate load. Subsequently, the pre-cracked beams were repaired by bonding steel plates of 6 mm thickness and 75 – 175 mm widths, which varied in increments of 25 mm. Externally bonding steel plates to pre-cracked reinforced concrete beams increased their load capacities by more than 100%, compared to the control beams. Except for specimen PB60-175, there is generally increase in the capacity of the repaired beams with increase in the width-to-thickness ratio of the steel plates. Beams that were pre-cracked at a lower load level (serviceability load) reached higher strengths than the beams that were pre-cracked at a higher load level (85% of the ultimate load capacity). In all tested beams, the experimental moment of resistance did not reach the code-predicted moment of resistance, calculated using EN 1992-1-1.
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Repair of reinforced concrete beams with adhesive Bonded steel plates
- Authors: Ngidi, Sandile Daniel , Dundu, Morgan
- Date: 2016
- Subjects: Flexural strength , Steel plates , Concrete beams
- Language: English
- Type: Conference proceedings
- Identifier: http://hdl.handle.net/10210/91849 , uj:20153 , Citation: Ngidi, S.D. & Dundu, M. 2016. Repair of reinforced concrete beams with adhesive Bonded steel plates.
- Description: Abstract:An investigation of the behaviour of reinforced concrete beams repaired with steel plates at its soffit is presented in this paper. Reinforced concrete beams were preloaded to 85 % of their ultimate capacity and subsequently repaired by bonding steel plates of different widths. Different widths of steel plates were used in order to determine the width-to-thickness ratio that will promote ductile behaviour. It is shown that strengthening of significantly cracked beams by bonding steel plates is possible and beams can be restored to stiffness and strength values superior to those of the original unplated beams.
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