A Study on Thermal Efficiency of Heat Testing Machine for Heat Transfer of Concrete at High Temperature

摘要

The deformation of building frameworks can lead to critical disasters such as building collapse. Loads, thermal expansion and creep are generally known factors, which cause deformation. High temperature due to fire can also be one of the major factors since concrete deterioration can affect the performance of building structures and eventually can weaken the frameworks. It is, however, difficult to estimate the influence of fire on concrete structures and evaluate the performance of fire resistance design. Many researchers have carried out experiments using small-scale specimens to tackle this issue and it was shown that specimens can reflect the real behavior of structures reasonably well. Nonetheless, it is challenging to achieve uniform temperature rise throughout the specimens while heating the structure as concrete has low thermal conductivity. Many different heating methods were used in recent studies to overcome this problem; however, one cannot compare the results directly to other results due to the variation of the experiment conditions. In this study, therefore, a new heating and loading method was suggested which combines the existing heating systems. Several experiments were carried out to show that a new method can maintain uniform temperature while heating so that the experiment can produce more accurate data.