| 摘要 |
A profile beam having a working surface constituted by alternate ridges and grooves is drawn, while being vibrated and whilst while to the application of a uniform downwardly directed force, across the surface of cement which has been laid to form a road, airplane runway or the like and which is still plastic, whereby parallel grooves are formed in said cement by the ridges. The grooves, which constitute the texture applied to the road surface, may extend at right angles to the traffic flow direction and will in that case be parallel to one another throughout or may make an angle of less than 90 DEG with the traffic flow direction
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