| 摘要 |
<p>The precast concrete paving slabs have a stepped edge to obviate the chipping of the upper surface edges. At least one of the vertical edges of the slab has a right angled stepped projection. The projection may extend over the lower third of the slab edge, and presents an offset lower vertical face. The slabs are installed with a stepped edge a butting a plane vertical edge, thus, forming a gap between the abutting top edge zones. The slabs may, thus, settle and rotate without the upper corners coming into contact and chipping.</p> |
