由于次故障循环负荷而导致的纤维状环的机械和结构变化
Jack Seifert1, Lance L Frazer2, Dennis Maiman3
1Marquette University, Milwaukee, WI, USA; Medical College of Wisconsin, Milwaukee, WI, USA; Zablocki Veterans Affairs Medical Center, Milwaukee, WI, USA.
Acta biomaterialia
|August 29, 2025
概括
重复的拉力负荷显著降低了纤维状环 (AF) 的机械性能,但没有改变最终的组织强度. 结构分析显示弹性纤维破裂没有原骨折,
科学领域:
- 生物机械工程
- 脊柱生物力学
- 组织力学
背景情况:
- 纤维环 (AF) 对于脊柱的稳定性至关重要,但其对重复拉伸负荷的反应尚未完全理解.
- 脊柱的退化和损伤导致脊柱衰弱.
研究的目的:
- 在重复的拉力负荷下量化纤维环 (AF) 的剂量依赖的机械和结构变化.
- 调查不同强度和循环数量对AF特性的影响.
主要方法:
- 使用了三个步骤的方案:损伤前的特征,通过循环负荷诱导损伤 (400-12,800循环; 11-44%的应变),以及损伤后的特征.
- 评估了机械性能 (动态,粘弹性,准静态) 和结构完整性 (组织学,F-CHP染色).
主要成果:
- 循环负荷导致AF弹性和粘弹性降低,接近100%的降低.
- 过渡应变大小受到影响,但最终的机械性能保持不变.
- 结构分析显示裂和原纤维脱, 但没有显著的原纤维变性.
结论:
- 重复的拉力负荷严重损害了AF的动态和粘弹性功能.
- 结构损伤涉及弹性纤维破坏, 而不是原骨折,
- 这些发现为了解AF退化和损伤机制提供了基础数据.
相关概念视频
Plastic Deformation in Circular Shafts
229
When materials are subjected to forces that surpass their yield strength, they undergo a process known as plastic deformation. This results in a permanent alteration or strain in their structure. This concept can be specifically applied to circular shafts, where the deformation leads to a change in its shape. The precise evaluation of this plastic deformation requires understanding the stress distribution within the circular shaft, which is achieved by calculating the maximum shearing stress in...
229
Fatigue
237
Fatigue occurs when materials rupture under repeated or fluctuating loads, even at stress levels far below their static breaking strength. It typically results in brittle failure, even for ductile materials. It is a critical consideration in designing machines and structural components subjected to repetitive or varying loads. The nature of these loadings can range from fluctuating loads like unbalanced pump impellers causing vibrations to repeatedly bending a thin steel rod wire back and forth...
237
Relation between Poisson's ratio, Modulus of Elasticity and Modulus of Rigidity
326
Deformation occurs in axial and transverse directions when an axial load is applied to a slender bar. This deformation impacts the cubic element within the bar, transforming it into either a rectangular parallelepiped or a rhombus, contingent on its orientation. This transformation process induces shearing strain. Axial loading elicits both shearing and normal strains. Applying an axial load instigates equal normal and shearing stresses on elements oriented at a 45° angle to the load axis.
326
Plastic Behavior
261
A material's elastic behavior is characterized by the disappearance of stress once the load is removed, allowing the material to return to its original state. However, when stress surpasses the yield point, yielding commences, marking the onset of plastic deformation or permanent set. This change from elastic to plastic behavior is influenced by the peak stress value and the duration before the load is removed. An intriguing observation occurs when a specimen is loaded, unloaded, and...
261
Normal Strain under Axial Loading
656
Normal strain under axial loading is an important concept in the field of mechanics of materials. Axial loading implies the application of a force along the axis of a material, like a column or bar. This force can either compress or stretch the material. In the context of axial loading, normal strain is the deformation experienced by the material in the direction of the loading force. It's calculated as the change in length divided by the original length of the material. This unitless ratio...
656
Eccentric Axial Loading in a Plane of Symmetry
285
Eccentric axial loading occurs when an axial load is applied away from the centroidal axis of a structural member. This scenario is common in engineering, where structural elements may not be directly aligned due to various design or functional requirements.
285


