Abstract: A method of repairing a road surface includes providing a hopper mounted on a spreading vehicle and means to spread material carried in the hopper over depressed areas of the road surface to fill them with the material. At ambient temperature, a batch of patching slurry is mixed comprising aggregate, asphalt emulsion, water, Portland cement, and a retarding agent operative to increase a break time of the patching slurry, and the batch is deposited into the hopper. The spreading vehicle is maneuvered to spread the patching slurry successively over a plurality of depressed areas until the hopper is empty. The ingredients of the patching slurry are adjusted to provide a patching slurry having a break time sufficiently long to allow the hopper to be emptied before the patching slurry begins to set, and sufficiently short to allow traffic to pass over a filled depressed area within a desired time.

Abstract: A method and apparatus for marking a line, such as the centerline, along a roadway, using a vehicle carrying paint marking apparatus, in which a pair of television cameras, one mounted on each side of the vehicle, view the edges of the roadway and project the images onto a split screen. By keeping the images on the screen in a predetermined relationship the operator can steer the vehicle in a path along the roadway uniformly spaced from its edges. Preferably a third camera, centrally located on the vehicle, views the vanishing point of the roadway when straight and the image of the vanishing point is registered with a predetermined mark associated with the screen.