石器的使用是一个力学作用过程,其功能部位(有效刃缘)在使用过程中,常常会出现不同程度的磨蚀或者崩损,这是由于石器刃缘处受到加工对象的反作用力而形成的。本文针对百色旧石器中手斧、手镐等大型工具类型出现较多的具有显著功能特点的舌形刃缘,尝试了用有限元方法做应力分析。通过对百色盆地13个地点(或遗址)的44件石器的舌形刃缘所进行的3D力学模型分析表明,这类工具受力是不均匀的,舌形刃缘部位是高应力部位,当外力加载到一定阈限时,舌形刃缘会发生崩损,而器身不发生破坏,这与实际标本观察结果相吻合。结果还表明在模拟纵向受力(代表劈裂和砍砸)和横向受力(代表挖掘)两种工况下,纵向受力的应力值远小于横向受力,说明这类工具可能更适于劈裂和砍砸。本文为有限元方法在石器力学研究方面的应用作了有益的尝试。
In the mechanical process of tool utilization,abrasion or damage from counterforce on worked materials can often occur in differing degrees on the effective edge of the tool.In this paper,a trial application of the Finite Element Method (FEM) is applied to the analysis of tongue-shaped edges that are often observed in large tools such as handaxes,picks,and choppers from many Paleolithic sites in the Baise(Bose) Basin.Through a three-dimensional computer modelling programme the mechanical analysis of 44 stone artifacts with tongue-shaped edges(from 13 sites) shows that stress distribution on these tools was not uniform with the maximum stresses occurred along the tongue-shaped edges.In the FEM model of longitudinal and transverse load simulation experiments,edges began to appear damaged when the load was raised to the threshold but without destroying of the non-edge body part;an observation supported with archaeological specimens.These research results also indicate that the stress value of longitudinal load is much lower than that of transverse load,and under both conditions of simulating tongue-shaped tools these shapes were shown to be more applicable to splitting and chopping behaviors.This work demonstrates the value in applying FEM to the study of stone tool function.