| Summary: | 博士 === 國立臺灣科技大學 === 營建工程技術學系 === 86 === The research is to study two types of sprayed fire-resistive material - porous and fibrous types, with regard to their relationship among the factors such as moisture content, pore structure, high temperature thermal conductivity and fireproof capacity. The research results indicate, in the sprayed fire-resistive material, there has a close relationship between moisture content and diffusive behavior, and there has positive relationship between the specimen thickness and curing humidity. After heated, moisture in the specimen will diffuse inwardly and finally accumulate on the steel plate surface until it has been totally boiled and vaporized, and therefore a sign that steel plate temperature has a delay at 100℃ is found. The specimen with higher moisture has a longer delay time but porosity after moisture vaporized has bad influence to fireproof capacity. Pore structure in the specimen will have an increase in respect of pore size and porosity following the increase in temperature. The relationship between the density and thermal conductivity may be explained through three different temperature ranges - when at low temperature and with low density, there will have low thermal conductivity; when at medium high temperature, following the rise in temperature, the one with lower density will gradually have higher thermal conductivity; when at high temperature, radiation in the pore will be increased to result in sharp increase in thermal conductivity and the increase in heat transfer at high temperature. Chemical ingredient of composition heat absorbing and disintegrating process may cause smaller increase in thermal conductivity. In this research, digression of two types of sprayed fire-resistive material may use linear relationship for representing the thermal conductivity under changing temperature.
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