| Title |
Study on the Behavior of Microstructure and Spalling Mechanism by Heat and Moisture Movement in Concrete under Fire Environment |
| Authors |
Ko Jeong-Won ; Ryu Dong-Woo ; Lee Mun-Hwan ; Lee Sea-Hyun |
| Keywords |
Spalling ; High Strength Concrete ; High Temperature ; Moisture Movement ; Moisture Content Rate ; Micro-Structure ; Vapor Pressure |
| Abstract |
Heat and moisture transfer in concrete is related with moisture behavior in pore structure during fire. This moisture behavior affects thermal conductivity and pore pressure of concrete, finally having a great effect on mechanical performance of concrete. In this study, specimens are controlled the moisture content rate by variation of microstructure at the concrete surface with variation of curing method. The variation of microstructure, moisture transfer and inner pressure variation in concrete during fire affecting spalling of concrete is examined experimentally from the microscopic point of view.The result is as follows : With regard to pore structure variation of concrete after high temperature, it is verified that pores are failed by rapid rising temperature and become large voids. It is also verified that thermal conductivity of concrete depend on continuance of pore structure in concrete and as concrete strength is higher, possibility of spalling increases because of restrained moisture transfer and rapid rising vapor pressure. |