Concrete Roads
and Their Construction

MECHANICAL DEVICES FOR MAKING ROADS 165 It is, however, preferable, when a sufficient length of roadway is constructed to justify the expense, to mount the bridge on end wheels, and to provide it with a simple propelling mechanism. A particularly effective arrangement developed by the Walker- Weston Co., Ltd., 7 Wormwood Street, E.C.2, used in construct- ing concrete roads at the Victoria Docks of the Port of London Authority, is so arranged that once the road-bed is graded and the reinforcement laid thereon there is afterwards no necessity for any machines ormen to stand on. the road formation (see Figs. 116 and 117). It consists of a light timber framework structure completely spanning Fig. 115.—Showing self-propelling Template and Tamper. the whole width of the road, and carried on either side on a bogie mounted on rails. One bogie mounted on. a track of 4 ft. 8£ in. gauge carries an electrically-driven concrete mixer, and also an electric motor driving a pair of friction winches. The bogie on the other side of the road is mounted on a 24-in. gauge track and carries the other end of the framework. This framework is covered over with tarpaulin, and its interior can easily bo lighted or heated so that work can proceed, if necessary, by day and night, and also in frosty weather. To the under side of the ridge of the framework structure is attached a cableway actuated by friction winches, by means of which the concrete skip is conveyed from the concrete mixer to any part of the road under the tent. Boards laid opposite each other, transversely across the “ tent,” form a platform or bridge on which stand the two men who work