NONLINEAR STRESS-STRAIN BEHAVIOR OF CORTICAL BONE

皮质骨的非线性应力应变行为

• 批准号: 6693758
• 负责人: DWIGHT T. DAVY
• 金额: $ 25.89万
• 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 2007-04-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6693758
• 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（申请人逐字逐句）：这是一项继续 人皮质骨非线性应力-应变行为的研究 从随时间变化的损伤累积过程的角度来看。的 在正常人骨中发生的损伤累积过程 明白描述这些过程并开发预测模型 对理解骨骼的脆弱性和骨骼 重塑实现我们预测破坏过程的长期目标 与体内加载条件相关的研究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。目前建议的目的是扩大我们的 时间相关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）由给定的加载模式引起的损伤 影响所有模式下的机械性能; 2）这些相互作用是依赖的 对微观结构损伤形态的影响。具体目标是：1。 测量每种单一损伤模式（拉伸、压缩和 扭转）对人皮质骨机械性能的影响 在所有加载模式下的降解。具体来说，我们将确定 的粘弹性和单调强度的影响 拉伸、压缩和扭转。2.测量复合损伤的影响 人体机械加工样本的模式（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，我们将确定复合模式损伤对 拉伸、压缩和拉伸时的粘弹性和单调强度， 扭转3.获得微观结构损伤的形态测量， 将微观结构损伤的形态特征与 机械性能退化实现这些目标将产生信息 这对开发可用于预测损害的模型至关重要 一般荷载条件下的累积。述信息标识 损伤模式和机械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 也将直接有助于明智地解决问题， 骨骼脆弱性和因衰老或 疾病