Biomechanics on the Growth and Deformation of Living Tissues and its Applications to Engineering

该项目的目的是：1)研究活组织和器官对各种机械环境的功能适应；2)将最佳适应机制应用于新的工程方法的开发；3)建立一个新的国际合作研究活动组织。主要研究结果如下：1.随着血压的升高，动脉壁厚度迅速增加，使管壁应力保持在生理范围内，弹性模量值等材料性质也随之发生变化。释放张力后，抗拉强度(断裂载荷除以初始横截面积)迅速而显著地降低，而强度不受超应力的影响。为了应对这些力学环境的变化，韧带横截面积补偿性增加，使结构强度保持在正常水平。在考虑气体…的情况下建立了气路-肺系统模型较多的呼吸道输运、肺的变形行为和表面张力、肺泡与血液之间的气体交换等，成功地应用于呼吸力学的模拟。提出了一种基于平面应力的三维有限元模型，用于人体整个腰椎的应力/应变分析，并成功地应用于分析了正常脊柱和病变脊柱在不同载荷条件下的应力分布。在生物系统中观察到的功能适应有可能应用于工程领域，例如，结构设计的生长应变法。所开发的分析生物系统中固-液-气相互作用的技术将对类似复杂工程系统的设计和分析非常有用。在该项目研究人员的行动下，建立了世界生物力学委员会，以有效地交换信息和进行国际合作研究。较少

The purposes of this project were : 1) to study the functional adaptation of living tissues and organs to various mechanical environment, 2) to apply the optimal adaptation mechanisms to the development of new engineering methodologies, and 3) to establish a new organization for international cooperative research activities. The main results obtained are :1. Arterial wall thickness increased promptly with the increase in blood pressure, Keeping the wall stress within a physiological range, followed by the change in such material properties as elastic modulus.2. Release of tension in the patellar tendon decreased the tensile strength (fracture load divided by initial cross sectional area) rapidly and remarkably, while the strength was not changed by over-stressing. In response to these variation of mechanical environment, the cross sectional area of ligament increased compensatively to keep the structural strength at a normal level.3. Air way-lung system was modelled considering the gas … More transportation in the air way, deformation behavior and surface tension of the lung, gas exchange between the alveolus and blood, and so on, which was successfully applied to simulate the respiratory mechanics.4. An in-plane stress-based 3-D finite element model was proposed for the stress/strain analyses in the human whole lumbar spine, and successfully applied to analyze the stress distribution in each component of the normal and diseased spines exposed to various load condition.5. The functional adaptation observed with living systems has possibilities of being applied to engineering field, for example, like the growth strain method for structural design. The technique developed to analyze the solid-fluid-gas interaction in biological systems would be very useful for the design and analysis of similar complex engineering systems.6. By the action of the investigators for this project, the World Committee for Biomechanics has been established for the efficient exchange of information and international cooperative studies. Less