A three-step process was developed to estimate fracture criteria for a human body model. The process was illustrated via example wherein skull fracture criteria were estimated for the Ford Human Body Model (FHBM)~a finite element model of a mid-sized human male. The studied loading condition was anterior-to-posterio
r, blunt (circular/planar) cylinder impact to the frontal bone. In Step 1, a conditional reference risk curve was derived via statistical analysis of the tests involving fractures in a recently reported dataset (Cormier et al., 2011a). Therein, Cormier et al., authors reported results for anterior-to-posterio
r dynamic loading of the frontal bone of rigidly supported heads of male post mortem human subjects, and fracture forces were measured in 22 cases. In Step 2, the FHBM head was used to conduct some underlying model validations relative to the Cormier tests. The model-based Force-at-Peak Stress was found to approximate the test-based Fracture Force. In Step 3, models of Cormier's setup with assumed fracture criteria were made such that they produced the experimentally observed spread of fracture forces. Moreover, iteration was conducted on the model-based stress and strain fracture criteria (viz., \u03c3 ult and \u03b5 ). The outcomes were analyzed via the same statistical approach applied in Step 1, and subject to \u03c3 is approximately equal to 125 MPa and \u03b5 ult is approximately equal to 2.2%, the model-based risk curve nearly identically recovered the reference test-based risk curve (i.e., P F E \u208b is approximately equal to 1.03 P \u207f and R\u2082 = 0.99).
A three-step process was developed to estimate fracture criteria for a human body model. The process was illustrated via example wherein skull fracture criteria were estimated for the Ford Human Body Model (FHBM)~a finite element model of a mid-sized human male. The studied loading condition was anterior-to-posterior, blunt (circular/planar) cylinder impact to the frontal bone. In Step 1, a conditional reference risk curve was derived via statistical analysis of the tests involving fractures in a recently reported dataset (Cormier et al., 2011a). Therein, Cormier et al., authors reported results for anterior-to-posterior dynamic loading of the frontal bone of rigidly supported heads of male post mortem human subjects, and fracture forces were measured in 22 cases. In Step 2, the FHBM head was used to conduct some underlying model validations relative to the Cormier tests. The model-based Force-at-Peak Stress was found to approximate the test-based Fracture Force. In Step 3, models of Cormier's setup with assumed fracture criteria were made such that they produced the experimentally observed spread of fracture forces. Moreover, iteration was conducted on the model-based stress and strain fracture criteria (viz., \u03c3 ult and \u03b5 ). The outcomes were analyzed via the same statistical approach applied in Step 1, and subject to \u03c3 is approximately equal to 125 MPa and \u03b5 ult is approximately equal to 2.2%, the model-based risk curve nearly identically recovered the reference test-based risk curve (i.e., P F E \u208b is approximately equal to 1.03 P \u207f and R\u2082 = 0.99).
