Damage Assessment of Concrete in Thermal and Dynamic Loadings

Jin-Won Nam,Alex Hak-Chul Shin

doi:10.5923/j.jce.20120206.01

Abstract

Thisresearch aims tothe development of combined damage model of concrete material under impact and thermal loading conditions. Down-scaled experimental works were carried out for the quantitative evaluation of combined damage from impact and thermal loading. The experimental results of this research include measurement of weight loss of concrete, chemical composition analysis, and strength degradation after impact and fire exposure. The damage of concrete under high temperature and impact loading conditions was studied with experimental measurements. Weight loss of concrete specimen shows the range of 1 % to 8 % with three different levels of temperatures: 200â, 500â, and 800â. At low and intermediate temperature levels, damage from impact loading was recovered and strength of concrete increased slightly after thermal loading. Rehydration might occur during the thermal loading. At high temperature level, damage of impact was combined with damage of thermal loading and strength of concrete decreased by 80 %.

Highlights

Accidental events such as traffic accidents, fires, explosions, and natural disasters can happen at any time.A mong those accidental events, it is acknowledged that the most frequent are fire and traffic accidents
The damage of concrete under h igh temperature and impact loading conditions was studied with experimental measurements
Weight loss of concrete specimen shows the range of 1 % to 8 % with three different levels of temperatures: 200°C, 500°C, and 800°C

Summary

Introduction

Accidental events such as traffic accidents, fires, explosions, and natural disasters can happen at any time.A mong those accidental events, it is acknowledged that the most frequent are fire and traffic accidents. By co mparing the compressive strength of specimens before and after co mb ined loadings, the effect of impact energy on the thermal damage of concrete can be deduced. The weight loss of concrete specimen due to thermal loading was measured. At a high temperature of 800°C (level C), 8 % of weight loss was observed.Due to the small size (100 mm x 66.7 mm) of the specimen after cutting, the heating anddehydration process was faster than typical concrete structures, and the different size effect should be further studied. The strength degradation of concrete specimens was measured after impact loading and consecutive applied thermal loading, respectively.

Discussions

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Conclusions and Further Studies