Retrofitting, Rehabilitation and increasing the Load Capacity of Concrete Members by a New Method Based on Epoxy Injection

Document Type : Research Paper

Authors

Department of Structures and Earthquakes, Faculty of Civil Engineering, Shahid Rajaee Teacher Training University, Tehran, Iran

Abstract

In the past decade significant research on strengthening, repair and increasing load capacity of concrete structures is carried out by the researchers. Meanwhile, the new methods including the use of polymer fibers to provide confinement for concrete and injecting resin under pressure to fill the concrete cracks for a better continuity of a failed member are introduced. This paper introduces a new approach for strengthening a concrete member based on epoxy injection and in addition to strengthening and increasing the load capacity to repair concrete members. In this study, nine cylindrical samples were prepared, three as control specimens, two specimens with four holes and four specimens with eight holes. All holes   with a diameter of 10 mm provided by drill and then epoxy injection were carried out.  The purpose was to determine the strength increase and to reduce the lateral strain under axial loading. Two specimens with eight holes confined with carbon fiber reinforced polymers (CFRP) to observe the effect of such a confinement comparing to the normal confinement provided by CFRP. These holes were created in specimens with specific angles and distances from each other. The results show that the suggested epoxy injection method increased the strength and load capacity of the specimens in the non-linear range and the lateral strain is reduced. Epoxy injection plus confinement provided by CFRP resulted in a better performance.

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