中文摘要：

建立了一个天体脊椎T12-S1段的三维非线性有限元力学模型。利用三维坐标数据测量仪测量人体脊柱椎骨表面的结构教据，然后将脊柱椎骨结构的点云数据输入到有限元软件中进行建模，最后获得了完整的脊椎T12-S1段的三维非线性有限元力学模型。为使模型更接近人体脊椎的真实情况，模型中对脊椎的外形结构和内部组成以及各种韧带均进行了细致地描述。分析表明在振动过程中，腰椎的各椎骨在前后方向上的振动幅度各不相同。椎间盘去髓核会降低脊椎系统的响应频率，同时也降低了损伤附近运动段椎骨的前后振动幅度，但却增加了损伤附近运动段椎骨在垂直方向上的振动幅度．该脊椎T12-S1段三维有限元力学模型的建成为研究脊摊损伤的病理机制与器械植入、军工方面的人体实验模拟，以及与振动相关的机械产品设计与开发，提供了一个更全面的数学模型。

英文摘要：

A three-dimensional nonlinear finite element model of spine T12-S1 segment was developed. The surface structural data of dorsal spinal vertebrae were measured by a three-dimensional coordinate digitizer, and the point-cloud data of spinal vertebrae were input into a finite element software for modeling. In the end a three-dimensional nonlinear finite element mechanics model of spine T12-S1 segment was obtained. The T12-S1 model describes in details the external configurations and internal components of spinal vertebrae, as well as all kinds of ligaments, so that the developed model can approach the real human spine. The results indicate that vibration amplitudes of different lumbar vertebrae are not same in the anteriorposterior direction. The intervertebraI denucleation may decrease the resonant frequency of the spine, at the same time, decrease the anterior-posterior vibration amplitudes of the vertebrae near the injury level, but increase the vertical vibration amplitudes of the vertebrae near the same injury level The finite element mechanics model of spine T12-S1 segment may provide a more detailed mathematical model for investigating the pathologic mechanism and instrument implant of spine injury, military experiment simulation of human body, and the development of vibration-related mechanical products.