Fire testing of high strength concrete filled steel columns

Over the past few decades, composite columns have become a popular component of the structural skeleton. One such composite column is manufactured by filling steel hollow section tubes with high strength concrete. The use of steel and concrete together in this configuration has many advantages. However the current technique of providing adequate fire resistance to this type of composite column is by external fire protection which significantly adds to the cost of construction. Monash University has conducted research on the feasibility of using high strength concrete filled steel columns without any external fire protection in which part of the column perimeter is directly exposed to the elevated temperature atmosphere. This is the first experimental study with this temperature exposure condition for these types of columns. Various composite column sections were used in the furnace tests to study their behaviour and performance. This paper reports some results obtained from this experimental study.