镶嵌试件表面位移场的全息显示

DISPLACEMENT FIELD ON THE SURFACES OF CORE-CONTAINED ROCK SAMPLES DISPLAYED WITH HOLOGRAMS

摘要:

用激光全息干涉法研究了在单轴压力下的镶嵌试件的表面形变,显示了离面位移场的可见图象。发现在载荷达到破裂载荷的90%左右时,沿镶嵌边界出现剧烈形变带和宏观裂纹;当岩芯强度低于或等于外围介质强度时,这种剧烈形变带集中在岩芯以外的一侧;当岩芯强度高于外围介质强度时,这种剧烈形变带形成围空图象。镶嵌试件在一定程度上模拟了地壳的横向不均匀结构,观察它的表面形变过程有助于探讨震前地震活动图象的物理含义。

Abstract:

Holographic photograph is applied to study surface deformation of core-contained rock samples under single-axial pressure and visible image of off-surface displacement field is displayed. When load is 90% of the critical value, strong deformation zone and macroscopic cracks appear around cores. Such zone may be found on one side of the core, if the strength of core is below or equal to that of the peripheral material. If the strength of core is above that outside, deformation inside the core may be small in contrast to outside.
Based on the experimental results, a new explanation of 'gap'formation before earthquakes is proposed.