轴压下两体力学模型的转化条件及影响因素分析

Analysis of transformation conditions and influence factors of uni-body and bi-body models under axial compression

接触界面的相互作用是影响工程稳定的重要因素,基于接触面两侧介质的实际受力状态,采用一体两介质力学模型与两体两介质力学模型加以描述。通过一体和两体模型试件的轴压破坏试验,分析了两种模型的力学响应的差异,并认为:一体两介质力学模型在符合一定条件情况下可以转变为两体两介质力学模型。此外,还对影响两种力学模型性能的参数进行了分析。提出对一体两介质力学模型力学性能产生影响的参量是低强度介质与高强度介质的静载极限强度比k以及两种介质之间的黏结力c;对两体两介质力学模型力学性能产生影响的主要参量除了k之外,尚有两种介质的断裂韧度比ξ、体积比ω以及界面的粗糙程度。

The interactions between two materials contacted are important for stability of engineering projects.Based on the actual stress state of two contacted materials,uni-body and bi-body models are employed to study the phenomenon.Through analyzing the test results,we conclude that uni-body model can be considered as bi-body model under certain conditions.In addition,the parameters which affect the two models are also analyzed.There are two important parameters that affect the mechanical performance of uni-body model,one is the strength ratio k between two materials;and other is the cohesion c of contact surface.Apart from the main parameter k,fracture toughness ratio ？,volume ratio ？ and the surface roughness are influence factors for the mechanical behaviors of bi-body model.