求翻译：研发楼为框架结构，柱子采用砼柱，平面呈长方形，主柱网为7.2m x 8.4 m，地上建筑耐火等级为二级，地下耐火等级为一级,占地2147 m2，建筑面积为18584 m2，建筑高度19.65m。是什么意思？

R & D building frame structure, the pillars of concrete pillars, flat rectangular main column grid is 7.2mx 8.4 m, on the ground floor fire resistance rating of two underground fire resistance rating for an area of ​​2147 m2, building area is 18 584 m2. building height of 19.65m.

Research and Development Framework for building structures, pillars, on behalf the flat rectangular shape, the main column Web 7.2 M x 8.4 m above ground, fire-rated construction for level 2, the underground fire-rated for the level of 2147 M, and 2, and m2 floor space for 18,584 19.65 m, height of

The research and development building is the portal frame construction, the pillar uses tong the column, the plane assumes the rectangle, the king post net is 7.2m x 8.4 m, the ground building fireproof rank is two levels, the underground fireproof rank is the level, occupying a land area of 2147 m2

Research and development building frame structure, pillars with concrete columns, a flat rectangular, pillar NET 7.2m x 8.4 m, building fire resistance rating for the second time on the ground level, underground fire resistance rating level, covers an area of 2147 m2, floor space is 18584 m2, buildi

正在翻译，请等待...