... loading（charging），庄药 perimeter hole，周边孔 pilot tunnel，导洞 ...
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?周边眼
周边眼(perimeter hole)。沿隧道周边布臵的 炮眼称为周边眼。
双语例句
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At present, piles with circular are used in all casting bore-hole pile foundations, but these piles have smaller perimeter and smaller section modulus as compare with the rectangular ones;