| 摘要 |
A fiber reinforced polymer material lid or cover for a utility vault made from an unsaturated polyester thermosetting resin matrix, glass fiber reinforcement, an inorganic filler and an ultraviolet inhibitor. The lid or cover has a flat textured upper surface having a plurality of bosses having different heights extending above the upper surface and a bottom surface having an outer perimeter rim with a recessed interior cavity having a number of continuous support ribs extending through the recessed interior cavity from opposite sides of the outer perimeter of the rim to transfer load placed on the lid or cover and minimize deflection under the load to the outer perimeter rim. |
