The Investigation of Heat Performance and Thermal Conductivity of Different Wall Materials at High Temperatures

Abstract

Abstract:The current study investigated heat transfers at high temperatures and compressive strength after exposure to high temperatures of gas concrete, clay brick, rice husk bricks used as wall materials, and gypsum plaster and common plaster used as coating materials. Tests measuring apparent porosity, water absorption, bulk density and compressive strength were performed on the samples prepared in 100 mm x 100 mm x 100 mm size. In the high-temperature experiment, the samples with K-type NiCr-Ni thermocouple were placed in a specially designed laboratory furnace. The internal temperature of the furnace was set at 800 o C. The researchers found that out of the samples exposed to high temperatures compressive strength and thermal conductivity of the gypsum plaster mortar were better than those of the common plaster mortar. Furthermore, the gas concrete, a wall material, was found to have a low thermal conductivity. As a result, the gas concrete and common plaster mortar, which were exposed to high temperature, were found to be more durable than other materials and, therefore, more advantageous when used in construction.

Improving the Fire-Resistance Rating of Concrete Masonry Walls using Insulations An Experimental and Numerical Study

“…The thermal conductivity of concrete can be kept low by entrainment of air in the concrete or the use of lightweight aggregates in the mix. Hence, lightweight concrete is expected to have lower thermal conductivity values than normalweight concrete [18]. An increase in the porosity of concretes structure due to the losses in pore water or dehydration of the cement paste leads to a decrease in the thermal conductivity of concrete.…”

“…Expansion occurs in materials exposed to high temperatures. The expansion coefficient is associated with the water in the material [18]. It is not very important to consider this property in fire designs; however, when the concrete masonry is restrained, then it should be considered [4].…”

“…[18], formation of hardened cement paste (hcp) below 600 o C[14], further resulting in crack development and ruptures.…”