During a rather rough hockey game you are transversely slashed in the tibia, creating a 0.02mm...

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During a rather rough hockey game you are transversely slashed in the tibia, creating a 0.02mm defect. The cortical bone thickness in the tibia at the slash location is 17 mm, and we can assume that the tibia has the cross-section of a hollow cylinder at this point. Tomorrow you plan to run a marathon. Will your tibia fracture during the marathon? Assume C= 2.5 x 10-ºm(MN/m3/2)-2.5, m= 2.5, and each stride to be 1.2 m. o is in MPa. Consider the smaller magnitude of the critical stress intensity factor range. Table 9.5. Fracture toughness (K,) and toughness (G.) of cortical bone loaded in the longitudinal and transverse directions. These values are for mode I loading. as shown in Fig. 9.10. The fracture toughness values for human cortical bone are comparable to those of a tough ceramic, but an order of magnitude less those for aluminium and steel. Adapted from Martin et al. [20] with kind permission of Springer Verlag. 10 Tension Direction of fracture Bone type K (MN/m) G. (Jm) 6 Longitudinal Bovine femur 321 1388-2557 Bovine tibia 2.8-6.3 630-2238 2 Human femur 22-5.7 350-900 No. of cycles Transverse Bovine femur 5.49 3100-5500 -4 Bovine tibia 22-46 780-1120 Compression Human tibia 22-5.7 350-900 During a rather rough hockey game you are transversely slashed in the tibia, creating a 0.02mm defect. The cortical bone thickness in the tibia at the slash location is 17 mm, and we can assume that the tibia has the cross-section of a hollow cylinder at this point. Tomorrow you plan to run a marathon. Will your tibia fracture during the marathon? Assume C= 2.5 x 10-ºm(MN/m3/2)-2.5, m= 2.5, and each stride to be 1.2 m. o is in MPa. Consider the smaller magnitude of the critical stress intensity factor range. Table 9.5. Fracture toughness (K,) and toughness (G.) of cortical bone loaded in the longitudinal and transverse directions. These values are for mode I loading. as shown in Fig. 9.10. The fracture toughness values for human cortical bone are comparable to those of a tough ceramic, but an order of magnitude less those for aluminium and steel. Adapted from Martin et al. [20] with kind permission of Springer Verlag. 10 Tension Direction of fracture Bone type K (MN/m) G. (Jm) 6 Longitudinal Bovine femur 321 1388-2557 Bovine tibia 2.8-6.3 630-2238 2 Human femur 22-5.7 350-900 No. of cycles Transverse Bovine femur 5.49 3100-5500 -4 Bovine tibia 22-46 780-1120 Compression Human tibia 22-5.7 350-900