NONLINEAR STRESS-STRAIN BEHAVIOR OF CORTICAL BONE

皮质骨的非线性应力应变行为

• 批准号: 6284924
• 负责人: DWIGHT T. DAVY
• 金额: $ 27.07万
• 依托单位: CASE WESTERN RESERVE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 1996
• 资助国家: 美国
• 起止时间: 1996-08-01 至 2005-01-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6284924
• 关键词: atomic force microscopy; biomechanics; bone; human tissue; mathematical model; mechanical pressure; mechanical stress; statistics /biometry; tensile strength; viscosity

DESCRIPTION (Verbatim from the Applicant): This is a proposal to continue an investigation into the nonlinear stress-strain behavior of human cortical bone from the perspective of time-dependent damage accumulation processes. The damage accumulation processes that occur in normal human bone are not well understood. Characterizing these processes and developing predictive models have important implications for understanding skeletal fragility and bone remodeling. Achieving our long-term goal of predicting damage processes relevant to in vivo loading conditions depends on extending our work to understand how damage induced in one loading mode affects mechanical properties in other loading modes. The objective of the current proposal is to extend our initial experimental studies of time-dependent damage accumulation processes from single mode effects to multi-mode effects. The general hypotheses underlying our Specific Aims are: 1) damage induced by a given loading mode affects mechanical properties in all modes; 2) these interactions are dependent on the morphology of the micro-structural level damage. Specific Aims are: 1. Measure the effects of each single damage mode (tension, compression and torsion) in machined samples of human cortical bone on the mechanical property degradation across all loading modes. Specifically we will determine the effect of single-mode damage on viscoelastic properties and monotonic strength in tension, compression and torsion. 2. Measure the effects of combined damage mode (tension + torsion, compression + torsion) in machined samples of human cortical bone on the mechanical property degradation across all loading modes. Specifically we will determine the effects of combined-mode damage on viscoelastic properties and monotonic strength in tension, compression and torsion. 3. Obtain morphometric measures of the microstructural damage and correlate morphological features of micro-structural damage with measures of mechanical property degradation. Achieving these aims will yield information that is critical to development of models that can be used to predict damage accumulation under generalized loading conditions. The information identifying deleterious interactions between damage mode and mechanical degradation in multiple loading modes, and relating those interactions to damage morphology will also be of direct usefulness in knowledgeably addressing issues of skeletal fragility and alterations in damage behavior as a result of aging or disease.

描述(来自申请人的逐字记录)：这是一项继续 人皮质骨的非线性应力-应变行为研究 从依赖于时间的损伤累积过程的角度来看。这个 发生在正常人类骨骼中的损伤累积过程并不好。 明白了。描述这些过程并开发预测模型 对了解骨骼的脆性和骨骼有重要的意义 改建。实现我们预测损害过程的长期目标 与体内负荷条件相关的情况取决于我们的工作扩展到 了解在一种加载模式下引起的损伤如何影响机械性能 在其他加载模式下。目前提案的目标是延长我们的 含时损伤累积过程的初步实验研究 从单模效果到多模效果。一般假设 我们的具体目标是：1)由给定的装载方式造成的损害 在所有模式下影响机械性能；2)这些相互作用依赖于 关于微观结构层面损伤的形态。具体目标是：1. 测量每种单一损坏模式(拉伸、压缩和 扭矩)对人皮质骨机械性能的影响 在所有加载模式下都会降级。具体来说，我们将确定其效果 单模损伤对材料粘弹性能和单调强度的影响 拉伸、压缩和扭转。2.衡量复合损害的影响 人体机械加工样品的模式(拉伸+扭转、压缩+扭转) 皮质骨在所有加载模式下的力学性能退化。 具体地说，我们将确定组合模式损伤对 拉伸、压缩和压缩过程中的粘弹性和单调强度 扭力。3.获得微观结构损伤的形态测量和 微结构损伤的形态特征与测量方法的相关性 机械性能退化。实现这些目标将产生信息 这对于开发可用于预测损失的模型至关重要 广义加载条件下的堆积。该信息标识 损伤模式与力学退化之间的有害相互作用 多种加载模式，并将这些相互作用与损伤形态相关联 在明智地解决以下问题方面也将直接有用 骨骼脆性和损伤行为的改变是由于老化或 疾病。