单词	purlin
释义	purlin /ˈpəːlɪn / noun A horizontal beam along the length of a roof, resting on principals and supporting the common rafters or boards.Sinking the posts 18 to 24 inches deep will keep them from pushing in below ground level, and the roof beams or purlins supporting the glazing do the same for the top of the posts.... Roofs can be upgraded from thatch or asphalt-impregnated cardboard to clay tiles if the initial roof rafters and purlins are sized at the beginning to carry the weight of the heavier clay tiles. Insertions include three insulated wood stud curtain walls, steel Y-braces and I-beam purlins to aid roof support, and steel tension cables for lateral resistance. Origin Late Middle English: perhaps of French origin. Rhymes merlin
随便看	pea-soupy pea-stake pea stick peastone pea straw pea-struck pea stubble peasy peat peat ash peat-bank peatbog peat-coal peated peatery peat-free peat hag peat house pea-time peatiness peatland peat machine peat mire peat moss peat pot

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