Shotcrete for rehabilitation of fire affected building

摘要

This paper addresses to the assessment of shotcrete in rehabilitation of fire affected multistory reinforced concrete building. A multistory building having an overall area of about 19314m~2 with basement, ground plus 16 floors and a mezzanine floor, caught fire after 17 years of its completion. The fire was extinguished after 10 hours and thus it was heavily damaged by fire. A comprehensive damage analysis using all available nondestructive techniques were carried out to evaluate the extent of damage of the building. Different analytical expressions were applied to evaluate the temperature and duration of fire in the fire damaged building. After carrying out a detailed damage assessment, shotcrete was proposed to rehabilitate the most parts of the damaged building. To assess the effectiveness of shotcrete, first the most heavily damaged floor, was repaired by shotcrete. Load test was carried out on the slab before and after shotcrete. A very much encouraging results came out. The deflection was measured to be reduced to about 1/10th of the value which was measured before shotcrete application. Although, load test will be carried out on all treated floors, this paper includes the results of load test on one floor. The research work concludes the highly effectiveness of the shotcrete in rehabilitation of fire damaged reinforced concrete building.