一种微裂纹摩擦阻尼分析模型

摘要

Dispersed micro cracks are widely found in engineering materials. Specific damping capacity ( SDC) caused by friction of micro crack surfaces is investigated in this paper. The frictional energy dissipation ( FED) approach of individual micro crack is mod-eled analytical y. Then, the model is applied to macro-scale cantilever beams involving regular and random multi micro cracks re-spectively. FED and SDC of the beams with different micro crack density are predicted. The result indicates that FED ( and SDC) de-pends on the crack angle and location. The results of the theoretical and numerical modeling are of perfect consistence.%由微裂纹引起的摩擦阻尼普遍存在于各种材料结构中。研究了由微裂纹摩擦引起的能量耗散与摩擦阻尼。建立了包含微裂纹的单胞模型，基于单胞模型建立了包含任意裂纹角度的悬臂梁模型，分析了含有微裂纹的悬臂梁的能量耗散、摩擦阻尼，并与数值仿真结果进行了对比。结果显示，能量耗散、摩擦阻尼都与裂纹的密度有着很大的关系，所建立的理论模型与数值模拟结果有较好的一致性。