Stress-Strain Index

Stress-Strain Index

Der Stress-Strain-Index (SSI) (zu Deutsch: Verformungs-Spannungs-Index), eines Knochens ist ein Surrogat für seine Festigkeit bzw. Biegefestigkeit[1]. Der SSI dient primär zum Vergleich der Analyse von Querschnitt-Scans mittels QCT/pQCT-Systemen und den Ergebnissen von Drei-Punkt-Biegestests (Festigkeit).

Definition

Der SSI wird wie folgt berechnet:[2]

SSI = \sum_{i=0}^n {{r_i^2 a ({{CD} \over {ND}})} \over {r_{max}}}

Wobei:

Anwendung

Der SSI wurde entwickelt, um ein besseres Maß der Festigkeit eines Knochens [2] zu erhalten, als es die reine Berechnung des Flächenträgheitsmoments ermöglicht. Daher ermöglicht er den einfachen Vergleich von In-vivo-Messergebnissen zu Ergebnissen typischer Materialprüfungstests wie z.B: dem 3-Punkt-Biegestest.

Einzelnachweise

  1. ↑ Ward K, Roberts S, Adams J, Mughal M: Bone geometry and density in the skeleton of pre-pubertal gymnasts and school children.. In: Bone. 36, Nr. 6, 2005, S. 1012-8. PMID 15876561
  2. ↑ a b Hasegawa Y, Schneider P, Reiners C: Age, sex, and grip strength determine architectural bone parameters assessed by peripheral quantitative computed tomography (pQCT) at the human radius.. In: J Biomech. 34, Nr. 4, 2001, S. 497-503. PMID 11266673

Wikimedia Foundation.

Игры ⚽ Нужно решить контрольную?

Schlagen Sie auch in anderen Wörterbüchern nach:

  • Stress-strain index — The stress strain index (SSI), of a bone, is a surrogate measure of bone strength [cite journal | author = Ward K, Roberts S, Adams J, Mughal M | title = Bone geometry and density in the skeleton of pre pubertal gymnasts and school children. |… …   Wikipedia

  • Stress-Strain-Index — Der Stress Strain Index (SSI) (zu Deutsch: Verformungs Spannungs Index), eines Knochens ist ein Surrogat für seine Festigkeit bzw. Biegefestigkeit[1]. Der SSI dient primär zum Vergleich der Analyse von Querschnitt Scans mittels QCT/pQCT Systemen… …   Deutsch Wikipedia

  • Stress (physics) — Stress is a measure of the average amount of force exerted per unit area. It is a measure of the intensity of the total internal forces acting within a body across imaginary internal surfaces, as a reaction to external applied forces and body… …   Wikipedia

  • Stress (mechanics) — Continuum mechanics …   Wikipedia

  • Strain hardening exponent — The strain hardening exponent (also called strain hardening index), noted as n , is a materials constant which is used in calculations for stress strain behaviour in work hardening. In the formula σ = K ε n, σ represents the applied stress on the …   Wikipedia

  • Stress (biological) — Stress is a biological term which refers to the consequences of the failure of a human or animal body to respond appropriately to emotional or physical threats to the organism, whether actual or imagined. [ The Stress of Life , Hans Selye, 1956.] …   Wikipedia

  • stress — I (accent) noun accentuation, attention, beat, distinction, emphasis, force, import, importance, inflection, insistence, intonation, paramountcy, primacy, prominence, pronunciation, significance, superiority, tone, urgency, weight II (strain)… …   Law dictionary

  • Stress functions — In linear elasticity, the equations describing the deformation of an elastic body subject only to surface forces on the boundary are (using index notation) the equilibrium equation: where σ is the stress tensor, and the Beltrami Michell… …   Wikipedia

  • Infinitesimal strain theory — The infinitesimal strain theory, sometimes called small deformation theory, small displacement theory, or small displacement gradient theory, deals with infinitesimal deformations of a continuum body. For an infinitesimal deformation the… …   Wikipedia

  • Environmental stress cracking — (ESC) is one of the most common causes of unexpected brittle failure of thermoplastic (especially amorphous) polymers known at present. Environmental stress cracking may account for around 15 30% of all plastic component failures in service.H. F …   Wikipedia

Share the article and excerpts

Direct link
… Do a right-click on the link above
and select “Copy Link”