In KP1 type perforated brick masonry, expansion bolt especially design for perforated brick is prefer, because it can form "self- anchor" effect and hold tightly in brick hole.

KP1型矩形条孔烧结页岩多孔砖砌体墙上应采用空心砌体专用膨胀螺栓，因其能够形成可靠的“自螺母效应”。

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Now appears a sort of plastic expansion shell bolt, which has strong expansion anchor-hold.

为了解决这一问题，出现了一种具有强胀锚力的塑料胀壳式锚杆。

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