INVESTIGATION OF TUNNEL FORMWORK STRUCTURE RETROFITTED WITH JFRP BY FINITE ELEMENT METHOD

Abstract

In reinforced concrete structures, some repair and strengthening needs may arise before the service life expires. The most common of these strengthening methods are sheathing, reinforcement with steel flats or steel plates. In addition to these, reinforcements made with fiber-reinforced polymers (FRP) have recently gained great momentum in the world. Reinforcements made with FRP materials provide advantages in terms of application speed and ease. In addition, FRP materials do not cause large volumetric increases in the reinforced concrete element to which it is applied. They are usually applied as a thin layer. Therefore, they do not cause loss of space architecturally. These materials are highly resistant to external influences. Many studies have shown that FRP materials can work in harmony with reinforced concrete structures.In this study, a 5-storey building consisting of reinforced concrete shear wall and slab was modeled in the SAP2000 program. First, the existing structure was analyzed. Then, 2 mm thick JFRP (Jute Fiber Reinforced Polymer) was applied to one side of shear walls and analysis was made. The aim of this study is to examine the effect of the JFRP material applied to the reinforced concrete shear walls on the period and displacement values of the structure.As a result of the analyzes and comparisons made, it was seen that the dominant period of the JFRP applied structure decreased by 12.03% compared to the existing structure. The maximum displacement in the structure is reduced by 1.10% compared to the existing structure. The study showed that the JFRP material applied to reinforced concrete shear walls provides a significant improvement in the period value of the structure.