Unstable failure characteristics and performance improvement of water-high filling materials

ZHOU Qian; XU Huai-bing; LIU Juan-hong

doi:10.13225/j.cnki.jccs.2016.0832

Abstract：For the low strength and poor stability of water-high filling materials improves the property of it.The unstable failure characteristics of water-high filling materials was studied by stress-strain and creep test.The microstructure of water-high filling materials and the improvement mechanism of it were analyzed by using scanning electron microscopy (SEM) and different thermal analysis-thermal gravimetry (DTA-TG).It is found that the creep curve has decelerating and stable stage when stress level is low and it increase accelerating stage when stress level reach critical load.The stress-strain curve has initial deformation,elastic,plastic deformation and disruption four stages.The gel time shortened,compressive strength improved,elastic modulus increased,unstable failure critical load raised and deformation decreased of water-high filling materials after improvement.Owing to more ettringite crystals and alumina gel in the water-high filling materials after improvement,the microstructure of hardening body become more densification and bearing capacity improved.