含多组雁列构造试样的特征位移场与声发射的关系——应变空区的实验与理论探讨  

A STUDY ON RELATION BETWEEN ACOUSTIC EMISSION AND CHARACTERISTIC DISPLACEMENT FIELD ON THE SAMPLE WITH MULTI EN ECHELON STRUCTURES——THE THEORETIC AND EXPERIMENTAL EXPLORATIONS OF STRAIN GAP

作　　者：陈顺云[1] 许昭永[1] 杨润海[1] 赵晋明[1] 郝锦绮[2] 王赟赟[1] 熊秉衡[1] 王正荣[3] 

机构地区：[1]云南省地震局防灾研究所,中国昆明650041 [2]中国地震局,中国北京100081 [3]昆明理工大学激光研究所,中国昆明650051

出　　处：《地震学报》2002年第6期627-637,共11页Acta Seismologica Sinica

基　　金：中国地震局双重项目(9691309020301);国家重点基础研究专项经费(G1998040704)主要资助;中国地震局"十五"项目(2001BA601B02-01-02);云南省科技厅应用基础研究青年基金项目(98D019Q)部分资助.

摘　　要：针对唐山等大地震前出现的“形变空区”现象,依据实验和理论对应变空区进行了探讨. 实验过程中采用焦散线法、实时全息干涉计量方法(激光)图像摄影记录,同时进行微破裂(声发射)记录.依据固体损伤理论,结合微破裂定位对应变空区进行研究,得出两点结论:①应变空区在线弹性情况下出现是一种必然现象,且应变空区的位置相对稳定,与裂纹端部的应力集中相对应;②应变空区内几乎不发生微破裂.微破裂总是从高应力区产生,且几乎就发生在应力集中区与应变空区相联的条带内,最终表现为微破裂(声发射)的带状或成丛分布.主破裂总是从应变核(焦散阴影区)开始,然后向应变空区急剧发展,形成主大破裂,最终导致试样崩溃.Based on the phenomena, which the deformation gap was observed before the Tangshan Great Earthquake, this paper discusses the strain gap on test and theory. The (strain) patterns were recorded photographically by real-time holographic interferometry and shadow optical method of caustics, as soon as the loading process had been started. In the meantime, the AE (acoustic emission) signals were recorded by a microcrack information storage-analysis system. According to damage theory and location of microfracture, we have studied the stain gap and gained: ①it is necessary that strain gap appears under the condition of linear elasticity theory, and its situation is relatively stable, corresponding to stress concentration. ②Microfractures, which appear initially at area of high stress, occur rarely at the strain gap, and their locations are finally in the zone between the stress concentration area and the strain gap, which indicate the clusters or groups. However, the major macro fracture (final rupture) started from the shadow areas, and then grew quickly towards the strain gaps, which resulted in failure of sample.

关 键 词：声发射 应变空区 主破裂 微破裂 损伤理论 地震前兆 

分 类 号：P315[天文地球—地震学]