Double-K Fracture Model and Weight Function Method of Post-fire Concrete

Abstract:

Investigations on the residual fracture properties based on Double-K fracture model is implemented. The load-crack mouth opening displacement curves of ten groups specimens with maximum temperature of 600ºC are obtained to calculate the Double-K fracture parameters. Based on the Petersson tension softening curve, the cohesive fracture toughness is calculated both by weight function method and analytical integral method. The two calculating results demonstrate a good coincidence and the validity of Double-K fracture model to post-fire concrete is proved.