潜水电机壳体，包括机架，尾轴承架，法兰和罩盖总装，必须采用符合美国材料试验协会ASTM A - 48类别30标准的、密实的铸铁或更好的材料制造。

The submersible motor enclosure including frame, end brackets, flanges and cap assembly shall be constructed of close-grained cast iron, ASTM A-48, Class 30 or better.

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半柔性路面是一种新型的路面，其材料结构属于骨架—密实结构，作为其母体的沥青混合料则属于骨架—空隙结构。

The semi flexible pavement is a kind of new asphalt pavement, it's material structure is the framework closed texture, however, the mother asphalt mixture is framework void texture.

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通过现场爆破试验和碾压试验，研究坝体填筑材料的密实度要求和碾压参数；

Then the compactness postulate and roller parameter of embankment material are researched by blasting test and roller test on site.

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