中文摘要：

结合某项目特点，分别介绍了两向正交正放双层网架屋盖选型计算、结构设计的荷载、受力特性、杆件截面及节点设计等内容，对同类型项目屋盖结构设计有一定的参考价值。

英文摘要：

Combining with the characteristics of a project, respectively introduced the type selection calculation of two ways orthogonality posture place double layer grid roof, the designed loads, the characteristic of structure, the truss member section and the key joint design. The key is sues ＆ relevant anlysis method are summarized, which could be used as reference in the design.