| 摘要 |
Tesselation or paving element or tile comprising an underpart having two by two symmetrical side surfaces, of which one pair is converging and the other diverging in the direction of the upper surface, said part carrying at its upper surface a prism, the base of which is congruent with the upper surface, wherein said prismatic part makes up at least one-third, preferably more than half of the height of the element in order to improve the mutual interlocking in directions perpendicular to the surface of the paving as well as making the joints impenetrable for loose underlayer. |
