Behavior of Reinforced Concrete Beams Strengthened by Epoxy Bonded and Bolted Steel Plates

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Yos Sompornjaroensuk
ธนัตศักดิ์ ธีระเกตุ
วิกร โตวราพงศ์
ปวริศ โปษยะนันทน์
ปฏิภาณ จันทรวิชิต
Damang Dy


As is generally acceptable in most of the previous published researches that only the use of adhesively bonded steel plates for external strengthening of reinforced concrete beams has less efficient than the combinations of bonding steel plate and anchoring of the ends of steel plate. The strengthened reinforced concrete beams with no plate-end anchoring can usually lead to brittle debonding failures before the ultimate load is reached. With providing the mechanical plate-end anchorage to the strengthened beams, it is found that the mode of failure becomes the flexural ductile failure and the load carrying capacity of strengthened beam is increased. The purposes of the present study are thus to reexamine the efficiency and performance of the beams, and to present the response behavior for both strengthening singly and doubly reinforced concrete beams having plate-end and intermediate anchored bolts. The obtained experimental results are dealt with for the load-deflection relationships, and the strength capacities of the beams, namely, initial cracking load, yielding load, debonding load, and ultimate load.

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