Deleted member 1973
pastebin.com/Tb8AYcyk
- Joined
- Jun 8, 2019
- Posts
- 5,826
- Reputation
- 6,880
Understanding deformation will understand how to help grow taller
as the bone lengthening is a form of bone deformation.
The problem with stretching is that, the bone is plastic so it’ll bounce back to it’s original length. It’s also hard to generate enough force to stretch bone.
“Many natural structures use a foam core and solid outer shell to achieve high strength and stiffness with relatively small amounts of mass. Biological foams, however, must also resist crack growth. The process of crack propagation within the struts of a foam is not well understood and is complicated by the foam microstructure. in cancellous bone, the foam-like component of whole bones, damage propagation during cyclic loading is dictated not by local tissue stresses but by the heterogeneity of material properties associated with increased ductility of strut surfaces.
The increase in surface ductility is unexpected because it is the opposite pattern generated by surface treatments to increase fatigue life in man-made materials, which often result in reduced surface ductility. the more ductile surfaces of cancellous bone are a result of reduced accumulation of advanced glycation end products compared with the strut interior. Damage is therefore likely to accumulate in strut centres making the cancellous bone more tolerant of stress concentrations at strut surfaces. Hence, the structure is able to recover more deformation after failure and return to a closer approximation of its original shape{we would not want this in terms of lengthening bone, we don’t bone to return to it’s original shape we want it to be longer}.
“the presence of a more ductile strut surface forces tissue damage and associated permanent deformations into strut centers.”
“On unloading, struts that accumulate tissue damage in the centre (where stresses are lower) will recover more deformation from bending and torsion than struts accumulating damage at surfaces.”
as the bone lengthening is a form of bone deformation.
The problem with stretching is that, the bone is plastic so it’ll bounce back to it’s original length. It’s also hard to generate enough force to stretch bone.
“Many natural structures use a foam core and solid outer shell to achieve high strength and stiffness with relatively small amounts of mass. Biological foams, however, must also resist crack growth. The process of crack propagation within the struts of a foam is not well understood and is complicated by the foam microstructure. in cancellous bone, the foam-like component of whole bones, damage propagation during cyclic loading is dictated not by local tissue stresses but by the heterogeneity of material properties associated with increased ductility of strut surfaces.
The increase in surface ductility is unexpected because it is the opposite pattern generated by surface treatments to increase fatigue life in man-made materials, which often result in reduced surface ductility. the more ductile surfaces of cancellous bone are a result of reduced accumulation of advanced glycation end products compared with the strut interior. Damage is therefore likely to accumulate in strut centres making the cancellous bone more tolerant of stress concentrations at strut surfaces. Hence, the structure is able to recover more deformation after failure and return to a closer approximation of its original shape{we would not want this in terms of lengthening bone, we don’t bone to return to it’s original shape we want it to be longer}.
“the presence of a more ductile strut surface forces tissue damage and associated permanent deformations into strut centers.”
“On unloading, struts that accumulate tissue damage in the centre (where stresses are lower) will recover more deformation from bending and torsion than struts accumulating damage at surfaces.”
