考虑岩土材料变形时空非均匀特征的DSCM快速分析方法  

Fast analysis method for DSCM based on spatiotemporally non-uniform deformation characteristics of geotechnical materials

作　　者：李元海[1,2] 唐晓杰 LI Yuan-hai;TANG Xiao-jie(State Key Laboratory for Geomeehanics ＆ Deep Underground Engineering,Xuzhou 221116,China;School of＂ Mechanics ＆ Civil Engineering,China University of Mining and Technology,Xuzhou 221116,China)

机构地区：[1]中国矿业大学深部岩土力学与地下工程国家重点实验室,江苏徐州221116 [2]中国矿业大学力学与土木工程学院,江苏徐州221116

出　　处：《岩土工程学报》2018年第9期1610-1618,共9页Chinese Journal of Geotechnical Engineering

基　　金：国家重点基础研究发展计划(“973”计划)项目(2014CB46905);高等学校科学创新引智计划项目(B14021)

摘　　要：岩土材料在外荷载作用下其变形通常表现出时间与空间分布上的非均匀性特征,在应用DSCM（数字散斑相关方法）进行图像像素测点的相关搜索过程中,传统方法通常对于全部试验阶段的图像和同一幅图像上的所有测点均采用相同的搜索范围,显然,这是一个虽然简单但效率很低的图像搜索分析方法。提出一种依据参考网格的测点动态范围搜索方法（简称PDSS）,即首先利用常规搜索方法分析获得一个间距较大且覆盖正式分析范围的测点网格的位移,然后以其作为正式图像测点分析的参考网格,最后,对任一测点,以其所在的参考单元节点的最大位移作为该测点的搜索范围值,从而可实现与测点变形大小相适应的动态范围搜索。PDSS方法本质上是通过减少相关分析的像素点数量来大幅提高图像分析速度。试验检验结果表明,PDSS方法相对于普通方法的图像分析速度通常可提高10倍左右。研究成果解决了具有时空非均匀变形特征的岩土材料DSCM的快速优化分析问题,可进一步提高DSCM在岩土材料变形量测中的应用技术水平。The deformation of geotechnical materials under the external loads generally non-uniformly varies with time and distribution. However, the search radius or search range is conventionally invariable with all the experimental images analyzed through the whole process, as well as with the measuring points in one picture. The relevant search of the image pixels in such a case is conventionally conducted based on DSCM during the basic mechanical experiment and the model experiment research of the geotechnical materials, which is too straightforward to be efficient. In order to solve this problem, a new method named PDSS which can adjust the search range is proposed to increase the efficiency. This method starts with the measurement of grid displacement covering the whole scope of analysis. The separation distance of grids is comparatively large, and the statistics are gained through the conventional search method during this period. Then, what we acquired first will be used for the analysis of measuring points. Finally, the search range of any point will be fixed with the maximum displacement of the reference element node. Such a range can be adapted for the deformation of measuring points. Essentially, the efficiency of analysis is improved through reducing the number of pixels when the PDSS is applied. As is shown from the experimental results, the analysis speed can be increased by more than 10 times. PDSS can be used to solve the problem of fast DSCM analysis for rock and soil materials with spatial and temporal heterogeneity. The research results can further improve the application level of DSCM in experimental studies of geotechnical engineering.

关 键 词：数字散斑相关 岩土材料 非均匀性 变形量测 PhotoInfor 

分 类 号：TU411[建筑科学—岩土工程]