Behavior of High Performance Steel-Fiber Concrete Exposed to High Temperature in Terms of Spalling and Permeability

摘要

An experimental investigation was conducted on behavior of high performance steel-fiber concrete subjected to high temperature, in terms of explosive spalling and permeability. A series of concretes incorporated steel fiber at various dosages were prepared, and further processed to have a series of moisture contents. Explosive spalling tests were conducted on control plain concrete and steel fiber concrete. After explosive spalling tests, each of the specimens that didn't encounter spalling was sawn into two pieces. Crack observations and permeability tests were conducted on the sawn surfaces. The results prove that steel fiber is efficient to avoid spalling concrete under high temperature. The permeability increases significantly after thermal exposure, while it also exhibits an ascending trend with the increase of moisture content. Therefore it is concluded that steel fiber can play a positive effect on explosive spalling of high performance concrete under high temperature, as well as on permeability after thermal exposure.