| 摘要 |
<p>The sports surface is formed by laying a foundation (7) having at least one sloping face which drains towards an edge of the surface. The foundation is covered by a single layer (8) of crushed rock having a particle size of less than 4mm. in a matrix of chalk. The surface is surrounded by a hard border (13) which prevents the layer (8) from being washed away. A ditch is formed immediately outside the border and cota contains a drain (15) at the botton, the remainder being filled with an aggregate up to ground level.</p> |
