Experimental research on strengthening damaged concrete beams by size increase solution and horizontal anchors

Abstract

In the process of strengthening damaged reinforced concrete beams, it is usual of using sheets like FRP, CFRP, or GFRP to the outer surface of concrete structures. Alternatively, an additional layer of reinforced concrete may be poured around the damaged beam to enhance its size, thereby increasing its bearing capacity and allowing for the continued use of the damaged reinforced concrete beams. This paper presents an investigation of bearing capacity and the formation and propagation of cracks in completely damaged beams. The authors used experimental methods, focusing on the application of an additional layer of reinforced concrete on the two sides and bottom of the beam. Horizontal linking anchors were utilized to establish a connection between the existing and new concrete layers. The research findings indicate that the use of horizontal anchors can enhance the bearing capacity of the beam by 200% (from 75kN to 150kN) while only increasing the cross-sectional area of the beam by 150% for completely damaged beams. This applies to both normal reinforced concrete beams and those including 20% of hardened cocopeat as a substitute for sand in the concrete mix.