EXPERIMENTAL STUDY ON DOUBLE-K FRACTURE PARAMETERS AND FRACTURE ENERGY OF SELF-CONSOLIDATING LIGHTWEIGHT CONCRETE

Self-consolidating lightweight concrete (SCLC) is a new-performance type of concrete which has light self-weight and needs no vibration for compaction. The workability and durability of SCLC have been studied but the fracture properties of SCLC have not been reported yet. Six series of SCLC with different notch/depth ratios were prepared. By means of an experimental load-displacement curve, the initial cracking toughness and unstable fracture toughness were determined and fracture energy was calculated base on a boundary effect model. It is found that the initial cracking toughness increases while the unstable fracture toughness keeps a constant with the increase of the notch/depth ratio. The size-dependent fracture energy increases with the increase of the notch/depth ratio. The specific fracture energy is 116.1N/m, and the ligament length is 32.5mm.