Analysis of reinforced concrete chimneys under the effect of temperature change with finite element method

Industrial chimneys are tall, thin structures that help release gases into the atmosphere. Often referred to as gaseous stacks, they are located next to a steam generating boiler and the gases are directed through pipes into the chimney. Reinforced concrete (RC) chimneys are generally designed to withstand stresses from gravity, wind, temperature and earthquakes. In this research, the behavior of a reinforced concrete chimney under the influence of temperature changes was investigated and a 50 meter high reinforced concrete chimney was designed and modeled with the SAP2000 program. The chimney was exposed to three different temperatures (250°C, 500°C and 750°C) and the behavior of this chimney was examined, and values were observed without heat and under the influence of each temperature. The values of moments, forces, maximum potentials and displacements under each temperature were compared. And we get the value of the maximum main shear force Vmax, the maximum main torque Mmax, the maximum main voltage Smax and the displacements Ux, Uy and Uz. The results showed that there was a significant increase in the value of moments, stresses and shears when the temperature increased, and the amount of deformation and displacement that occurred with increasing temperatures. In this study, the destructive effects of the temperature effect on a reinforced concrete chimney are clearly demonstrated. It was revealed that the internal forces and displacements increased excessively in the reinforced concrete chimney. It should be noted that this effect may increase or decrease according to the selected model. The results in this study were obtained according to the model in this study. With the increase in temperature, there is an increase in displacements of approximately 100% from 250 °C to 500 °C, and approximately 75% from 500 °C to 750 °C. With the increase in temperature, very serious increases in maximum stresses (Smax) were observed for every 250 °C degree increase. These increases were found to be approximately 100% from 250 °C degrees to 500 °C degrees, and about 75% from 500 °C degrees to 750 °C degrees. And the same thing in Mmax and Vmax, In addition, Especially in Ux and Uy, extremely large increases were observed between the initial state and the heated state.