Abstract
Constitutive equations and a damage evolution equation of cortical bone were formulated to predict bone fractures and their patterns accurately in traffic accidents or falling. The constitutive equations can represent characteristic features of cortical bone, such as elasticity with strain rate dependency, viscoplasticity, and strength anisotropy as well as strength asymmetry of tension and compression. The damage evolution equation can simulate damage accumulation of cortical bone with rate dependency. Experimental data of uniaxial compressive and tensile loading tests of human cortical bones were used to validate these equations. Predicted stress-strain curves and failure points agreed well with those of experimental data at wide range of strain rates. This shows the present model can be used to predict bone, fractures in various impact situations of traffic accidents or falling.
