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| EFFECTS OF MEASUREMENT RANGE ON ESTIMATION OF TRACE LENGTH OF DISCONTINUITIES |
| LI Xiaozhao1，2，ZHOU Yangyi1，2，WANG Zhitao1，2，ZHANG Yangsong3，GUO Liang1，2，WANG Yizhuang1，2 |
| (1. NJU-ECE Institute for Underground and Geoenvironment，School of Earth Sciences and Engineering，Nanjing University，Nanjing，Jiangsu 210093，China；2. School of Earth Sciences and Engineering，Nanjing University，Nanjing，Jiangsu 210093，China；3. Department of Civil Engineering，Nanjing University of Science and Technology，Nanjing，Jiangsu 210094，China) |
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Abstract The extent of measurement range has a significant influence on estimation of trace length of discontinuity. However，measurement range is not considered in some of the current calculation formulas，though this parameter contained in some of the formulas，whether this influence could be showed in different measurement ranges still remain farther test and verify. So this paper attempts to make a comparative study on the basis of two types of data，one is created from Monte Carlo simulation，another is measured on a real outcrop. The influences of measurement range on the estimation of trace length by different formulas，the permitted minimum measurement range and its factors have been studied in this paper. The results indicate that some formulas may also contain notable errors when the sampling window is too large. Therefore，for the evaluation of the trace length of discontinuity，it should begin with the analysis of suitability and influence of measurement range；otherwise the sampling deviation would be still unquenchable even if complicated formulas are adopted. The edge effect and limitation of Monte Carlo simulation method for this issue have been found during this study. Also the suitability analysis in typical outcrops of candidate area for the geological disposal of high-level radioactive waste in China is made，which is helpful for the subsequent discontinuity investigation.
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Received: 04 June 2011
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2011, Vol. 30 
