哈氏系统破坏的微观结构分析

本文旨在通过五个长骨试样在五个不同载荷等级(2KN,3KN,4KN,5KN和6KN)的抗压试验,观察哈氏系统(Haversian System)——哈氏骨板和哈氏管——的变化情况.由一组显微照片可以十分清晰地看出:(1)在载荷等级低的情况(2KN),哈氏管几乎与未受力时一样,哈氏骨板亦然;(2)在载荷等级高的情况,哈氏骨板最弱的部分最先变形;(3)随着载荷的增加,哈氏系统破坏的形式十分复杂,断裂总是发生在骨的结合缘处. 同时,测量了变形后的哈氏骨板和哈氏管的有关尺寸.对试验中所观察到的现象,用线性粘弹性力学的理论予以解释.最后提出了骨单位为纤维增强的厚壁筒模型.     

长骨抗压性能

本文旨在对人的湿润的右股骨与右肱骨的试样进行轴向抗压试验,籍此得到股骨的弹性模量E=9.98×109N/m2,肱骨的弹性模量E=11.37×109N/m2.同时,与国内外的有关资料进行了比较以及讨论.本文还指出了骨组织呈现明显的粘弹性性质,滞后(辶回)线示于图3(a)和(b).并对试验过程中的一些力学现象作了解释.     

MECHANICAL FAILURE IN HAVERSIAN SYSTEMS ON THE BASIS OF MICROSTRUCTURE

The aim of this paper is to observe variations in the mechanical properties of Haversian systems including Haversian lamellae and canals, by means of the compressive test of five bone specimens subjected to different loads corresponding to 2KN, 3KN, 4KN, 5KN and 6KN respectively. From a series of related microscopic pictures it is clearly seen that: (1) in the lower level of loading (2KN). the Haversian canals much the same as the one unsubjected to loads, and conditions of Harversian lamellae are also the same, but, the individual Harversian canal was slightly bent; (2) in the case of the higher levels of loading, it is first deformed in the weaked portion of the Haversian lamellae; (3) with increasing loads, the fracture shapes of the Haversian sgstem are very complex, but the fractures always take place in the cement line between osteon s. At the same time, deformed dimensions of the Harversian lamellae and canals were measured. The observed phenomena were quaiitatively interpreted by the theory of t     

The compressive properties of long bones

In this study, compressive tests of the bones along the axial direction have been carried out on some wet specimens of the right femur and humerus, from which there have been obtained the elastic modulus of femur E=9.98×10⁹N/mM² and.’that of humerus E=11.37×10⁹N/m² Also comparisons and discussions have been made with reference to the available data reported abroad and at home.As indicated in this paper, bone tissues obviously possess viscoelastic properties. Their hysteresis loops are shown in Fig. 3 far and (b) and some mechanical phenomena observed during the test are illustrated elsewhere.     

THE COMPRESSIVE PROPERTIES OF LONG BONES

In this study.compressive tests of the bones alongthe axial direction have been carried out on some wetspecimens of the right femur and humerus.from whichthere have been obtained the elastic modulus of femurE=9.98×10~9N/m~2 and that of humerus E=11.37×10~9N/m~2.Also comparisons and discussions have been made withreference to the available data reported abroad andat home.As indicated in this paper,bone tissues obviouslypossess viscoelastic properties.Their hysteresisloops are shown in Fig.3 (a)and(b)and some mechani-cal phenomena observed during the test are illus-trated elsewhere.     

人的密质骨的力学性能

本文把骨组织看作是一种材料和骨骼系统的粘弹性结构元件,评述了它们的力学性能.首先描述了骨的结构,包括宏观结构、微结构和超微结构.随后是骨的力学性能.第三部分介绍了哈弗氏骨的力学模型.笔者指出,单个哈弗氏骨可考虑为正交铺设的胶原纤维增强的粘弹性厚壁筒.最后讨论了哈弗氏骨的应力-应变关系.显然,简单的弹性关系是不可用于实际的.      

MECHANLCAL FAILURE IN HAVERSIAN SYSTEMS ON THE BASIS OF MICROSTRUCTURE

The aim of this paper is to observe variations in the mechanical properties of Haversian systems including Haversian lamellae and canals,by means of the compressive test of five bone specimens subjected to different loads corresponding to 2KN,3KN,dKN,5KN and 6KN respectively. From a series of related microscopic pictures it is clearly seen that:(1) in the lower level of loading (2KN) ,the Haversian canals much the same as the one unsubjected to loads,and conditions of Harversian lamellae are also the same,but,the individual Harversian canal was slightly bent; (2) in the case of the higher levels of loading,it is first deformed in the weaked portion of the Haversian lamellae; (3) with increasing loads,the fracture shapes of the Haversian system are very complex,but the fractures always take place in the cement line between osteons.At the same time,deformed dimensions of the Harversian lamellae and canals were measured. The observed phenomena were qualitatively interpreted by the theory of the linear viscoelas-ticity.