건설재료시공학연구실

Building material & construction lab.

Abstract

A large amount of strength degradation of high strength concrete is occurred when it is exposed to elevated temperatures. Therefore, fire resistance performance of concrete has to be verified. Furthermore, the stability of the structure is likely to be decreased due to the deformation of structural member under constant high temperature condition. In this study, the thermal strain of high strength concrete with the compressive strength of 80, 130, 180MPa were measured under 25% of compressive strength loading condition. As results, consistent thermal strain of 80MPa specimen has been occurred up to 500 °C remaining in the expansion area. However, 130 and 180MPa specimen showed the shrinkage strain after 300 °C. Especially, creep rupture was occurred on 180MPa specimen at 700 °C in the creep strain experiment. Therefore, it is considered that decline of the elastic modulus and shrinkage strain of high strength concrete become grater at the elevated temperatures.