Crack Opening Displacement of Concrete Exposed to High Temperature

Abstract:

Wedge splitting test was carried out on the concrete exposed to high temperature to investigate the relationship between crack tip opening displacement ω and crack mouth opening displacement δ during the whole fracture process. It is found that the initial cracking load determined from δ ω curve shows a good coincidence with that determined from load crack mouth opening displacement (P δ) curve. The value of ω was calculated from δ based on the two parameters fracture model and hinge model, and the comparison with the experiment data show the two parameters fracture model has a better accuracy. Finally, the exponent relationship of ω and crack extension Δa was established.

Key words:post fire concrete; wedge splitting method; crack tip opening displacement; crack mouth opening displacement; initial cracking load