T. Nishikawa, S. Ito and H. Awaji Dept. Materials Science and Engineering, Nagoya Institute of Technology JAPAN Mechanical properties and fracture behavior of cement mortar sand were studied after curing for 7 days to 6 months . Decrease of bending…
T. Nishikawa, S. Ito and H. Awaji Dept. Materials Science and Engineering, Nagoya Institute of Technology JAPAN Mechanical properties and fracture behavior of cement mortar sand were studied after curing for 7 days to 6 months . Decrease of bending strength but increase of Young's modulus for mortar were observed the increase of sand amount. Large fracture energy was for mortar with sand/cement ratio = 1.0, and rising R-curve with the crack extension was also clarified for mortar. Particle-bridging at the fracture surface and microcracking at the crack tips mainly to fracture toughness. Critical crack length decreased with the increase of curing time, at which many crack generated inside of the sand particles instead of the interface. Large crack length was also estimated for the mortar with high sand/cement ratio due to the aggregating the sand. words: Bending strength, Young's modulus, Fracture Mortar 1 Introduction Application of fracture mechanics to cement paste, mortar or concrete has been performed to clarify their fracture behavior and design their suitable microstructure. Several books and review have been written by Shah et al. (1995), Cotterell et al. (1996) and Jennings (1988). A few numerical models based on the metal-matrix-composites (MMCs) were also proposed, regarding the cementitious materials as a two-phase composite with a homogeneous phase and a particle phase. Simenov et al.