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按试验室规模拟定了一种基于35mm胶卷照相术的逆分析法,以确定爆堆中已知的不合格大块百分率。按1∶40的模拟比例,试验了8组含不同百分率不合格大块的混合破碎岩石试样。进行照相研究的模拟试验条件如下:(1)台阶式爆堆;(2)部分挖掘爆堆的表面暴露;(3)重力分级的溜堆表面;(4)逐渐形成的锥形岩块堆的四分之一取量。最好的逆分析测定结果是第(4)项所有8种混合岩块的锥形堆。平均误差实际值为-0.16％,标准偏差范围±1.872。这是针对在用数字化仪处理最少25％的照相面积情况下不合格大块含量5～20％而言。最坏的结果是溜堆,在标准偏差范围为±4.174％时,实际平均误差为-1.462％。中等的结果是未扰动的混合岩块,在标准偏差为±2.862％时,实际平均误差为-0.186％。
An inverse analysis based on 35mm film photography was developed on a laboratory scale to determine the percentage of unacceptable chunks known in the blast. At a 1:40 simulation scale, eight groups of mixed crushed rock samples with different percentages of unqualified bulk were tested. The simulated test conditions for the photographic study are as follows: (1) step blast; (2) partial excavation of the surface of the blast exposed; (3) gravitationally graded skidding surfaces; (4) A quarter of the amount. The best reverse analysis is the conical heap for all eight mixed rock masses in item (4). The average actual error is -0.16% and the standard deviation is ± 1.872. This is for a mass content of 5-20% that is unacceptable for use with a digitizer to process a photographic area of at least 25%. The worst result is slippery heap, the standard deviation of ± 4.174%, the actual average error of -1.462%. The moderate result is undisturbed mixed rock mass with a true mean error of -0.186% at a standard deviation of ± 2.862%.