Grid for equipment of pump with cover inside building, has bars placed such that distance between lower edges of tilted surfaces turned toward each other is smaller than that of upper edges to retain gravel and aggregate embedded in mortar

摘要

The grid (28) has a set of bars (36) including two tilted surfaces (38), which form an angle and include an upper edge and a lower edge. The bars are placed such that distance (D) between the upper edges of the tilted surfaces turned toward each other is greater than maximum length. Distance (d) between the lower edges of the tilted surfaces turned toward each other is smaller than the distance between the upper edges so as to retain potential gravel and aggregates embedded in mortar.