Evaluation of fire damage of concrete slabs [electronic resource]
說明
280 p
附註
Source: Dissertation Abstracts International, Volume: 54-06, Section: A, page: 1978
Chairperson: Weilin P. Chang
Thesis (Ph.D.)--University of Florida, 1992
There are two major building structure damages caused by fire: the reduction of fire resistance and the reduction of strength. Both are important factors in determining the reusability of a structure after it has been exposed to fire. An experimentally validated analytical technique for evaluating the residual fire endurance of structural elements after fire is currently unavailable. Although nondestructive test methods have been used for evaluating the residual strength of concrete structural members, no systematic analysis has ever been done
The purpose of this dissertation is to conduct a comprehensive pilot study of residual fire endurance and strength of concrete slabs after exposure to fire. A small-scale fire test, two nondestructive tests, and a destructive test were conducted to evaluate the effects of three factors, i.e., exposure severity, re-curing condition, and re-curing time lapse, on the residual fire endurance, Schmidt hammer rebound number, pulse velocity, and compressive strength of concrete slabs made of typical Florida porous limestone and Type I Portland cement. A statistical model was established to investigate the effects of test factors on the results and the correlation between nondestructive and destructive test results. It was found that when concrete slabs are exposed to fire more than thirty minutes, the environmental factors do not affect the test results significantly, but the reduction of fire endurance is obvious. Therefore, the consideration of fire endurance is critical for fire damage evaluation and should not be overlooked. A preliminary investigation on using nondestructive test methods to evaluate both the residual fire endurance and strength of concrete slabs after exposure to fire is presented, and further studies to validate these methods are evidently needed. A reference is established for applications and further research
