Concrete Roads
and Their Construction

CONCRETE ROADS 60 sand ; and the proportions adopted were 1 part Portland cement, 1 part chippings, 1 part sand, and three parts stone. The amount of water used was from 1f to 2 gallons for every 6 cubic ft. of the materials taken separately, or, in other words, 1 f to 2 gallons for every cubic foot of dry cement. A portion of the road was laid with Pennant stone and a portion with limestone, with a view to comparison of results. A batch mixer is used, and while being spread the concrete is tamped with shovel and rammer and finished off with a floater about 1 in. thick and 7 ft. long. The finished work was covered with sand, which was watered daily. The road was not opened to traffic until one month after completion. The surface was not treated in any way and thus this is a concrete road pure and simple. Scotland Canmore Street, Dunfermline.—Canmore Street is one of the few “ level ” streets found in the south side of a city where hills and steep gradients predominate. Connecting, as it does, with the centre of the town at its west end and with New Row at its east end—the latter being the principal route to the lower railway station, and very steep in that portion which lies between Canmore Street and High Street—it has to carry a very heavy traffic. During the summer of 1916 a motor-bus service was inaugurated between the city and the dockyard at Rosyth, with its starting point at the west end of Canmore Street. The roadway, which has an average width of 15 ft. 6 in. between the kerbs, was originally constructed of whinstone setts 7 in. deep, laid without a concrete foundation, and soon gave way under the bus traffic, so much so that within a very few months it became dangerous. The then Burgh Engineer, Mr. P. C. Smith, submitted two schemes to the Town Council: one to lift the setts, lay a concrete foundation, and relay the setts, grouting the same with pitch ; and the othei' to discard the setts and lay the roadway with 6 in. of concrete reinforced with steel wire and surface sprayed with tar and chipped. The latter was adopted. The old setts having been removed and the surface brought to the proper contour and level, 2 in. of concrete was laid down and on this was spread the reinforcement. Two widths were required to cover the roadway, and an overlap, averaging 8 in.,