| 摘要 |
<p>Residential areas are afforded protection from noise, emanating from roads, railways or industrial plant, by a wall. Elements (1) in this wall are made up from a box-shaped wall unit (2), with rear walling enclosed in a frame (4), front sheet metal plate (5) set on the frame, and inlay of insulating material. Rear walling and frame are cast in one piece from polyester concrete. The unit can be strengthened by lengthways and/or transverse ribs (7,8). The front plate can be clamped on. This is economical to make, and adequately complies with official guide- lines on protection from noise.</p> |
