COMPUTER AIDED DESIGN OF FRP WRAPPED FIRE-DAMAGED RC ELEMENTS

Abstract

Performance of concrete in fire is high and can resist high temperature. So it is better to reuse the concrete structures even after fire by retrofitting the structures. To repair structures, the residual strength of concrete needs to be evaluated. Hence, several techniques and methods can be applied to evaluate the residual capacity of structures. The residual capacity can be judged on the basis of change in colour and crack development after fire. Some of the lab testing such as water immersion, the rebound index and microscopy a can be used to determine the residual strength. But with development of advance techniques, certain software packages can be used to determine the residual capacity of structure after fire. After assessment of residual strength of RC elements, it is required to be repaired. There are several active and passive strengthening techniques that can be employed for the retrofitting of structures depending upon the strength regain requirement, structural requirements and structure as whole. Some of the techniques such as external post tensioning, bonded steel plate reinforcement etc are being used in day to day maintenance. But with advancement in technology and increased interest in the use of FRP materials are coming in to use for the strengthening the structures. In this studies certain numerical models available in literature is being employed to determine the post fire residual capacity in flexure. The thermal profile obtained from the thermal analysis using ABAQUS FEA packages. These thermal profiles were used for section analysis to reach the ultimate goal of determination of residual capacity.