Штукатурные составы как огнезащита стальных конструкций объектов нефтегазового комплекса

Abstract

Purpose. The article describes experimental studies of steel columns samples with two types of fire resistant plasters to determine time of reaching critical temperature and loss of bearing capacity by samples. Methods. Experimental studies of two plaster compositions types, each of which is a mixture of Portland cement, vermiculite and other binders with target additives and fillers have been conducted. The ELCUT software package has been used to simulate thermophysical processes of the considered steel structures. Findings. Simulation of steel structures heating has showed a good correlation (not more than 5 %) with the results of the experiment. Thermophysical characteristics of plaster fire resistant coatings in the temperature range from 20 to 1 000 °C have been determined by solving the inverse task of thermal conductivity using the finite-element model in the ELCUT software package. Nomograms of steel structures heating under the influence of standard and hydrocarbon regimes of the fire with use of plaster composition have been given. Research application field. The obtained results can be used in the technical documentation of fire resistant compositions done by manufacturers for the possibility of simulating and forecasting plaster coating consumption depending on the given thickness of the metal. Conclusions. It has been shown that the difference of thermal conductivity values under standard and hydrocarbon fire conditions at 1 000 °С is 8–10 %, the difference of heat capacity values at 1 000 °С is 10–15 %. It has been found that the fire-resistance limit in the hydrocarbon fire regime is observed 40–50 minutes earlier with comparable flow rates and given metal thicknesses.