Tensile Behavior of Damaged-steel Plate Strengthened by One-sided CFRP Patch in Acidic Environment

Document Type : Original Research Paper


1 Department of Mechanical Engineering, Mashhad Branch, Islamic Azad University, Mashhad, Iran.

2 Mechanical Engineering Department, Faculty of Engineering, Ferdowsi University of Mashhad, Mashhad, Iran.


Today the adhesively bonded joint of FRP/steel for repair and strengthening are being widely used. In this case, investigating the effect of various mechanical loading, as well as harsh environmental conditions on this joint, is very important. In this paper, the strength of the damaged-steel plate reinforced with CFRP patches under acidic environment is investigated experimentally. The damage is considered in the shape of a central hole with two narrow central notches on two sides of the hole. In order to simulate more realistic conditions, the bonding of the patch to the steel plate is considered one-sidedly. To evaluate the amount of strengthening, the specimens are subjected to the simple tensile test at room temperature. The results of dry patched-specimens compared to non-patched specimens show significant reinforcement with at least 40% increase in load-carrying capacity and at least 50% increase in displacement. The comparison between the patched-specimens immersed for 8 weeks in concentrated sulfuric acid and the dry patched-specimens show no significant effect on the load-carrying capacity. However, the tests of standard CFRP specimens in a similar immersion environment show a reduction in modulus of elasticity and tensile strength compared to the dry CFRP ones.


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