利用数值分析软件RFPA^2D对5种不同端部条件下的岩石试样进行了数值模拟研究,讨论了垫板和岩样弹性模量不同比值下,端部效应和声发射之间的关系,得出了声发射的时间序列特征和空间分布的规律:Ep/Es〈1,有数次高频度声发射出现,声发射主要分布在试样的两个端部,中部出现较少;EP/Es=1,仅有一次高频度的声发射出现,声发射主要随机均匀地分布在试样中;Ep/Es〉1,有多次高频度的声发射出现,声发射主要分布在试样的中部。这些特征和规律为利用压力机做实验时,尽量避免岩石试样破裂过程受垫板干扰提供了很好的参考依据。
The rock acoustic emission (AE) under five kinds of different end effect was study using numerical simulation code RFPA^2D. The relationship between end effect and rock acoustic emission under five elastic modulus ratios ( Ep/Es ) of clamping plank and rock specimen were discussed. The time sequences and space distribution law of AE were got, i. e. , when Ep/Es 〈 1, a few high frequency AE occurred and mainly at the two ends but few at the middle of rock specimen; when Ep/Es = 1, only one high frequency AE occurred and random uniformity at whole rock specimen; when Ep/Es 〉 1, numbers of high frequency AE occurred and mainly at the middle of rock specimen. The characters and laws offer good references for avoiding the influence of clamping plank on the failure process of rock specimen during compression test of rock with press machine.