Concrete Roads
and Their Construction

186 CONCRETE ROADS at 143 Grosvenor Road, London, S.W.l, by the Concrete Utilities Bureau of 35 Great St. Helens, London, E.C.3. No book on. concrete roads would be complete without some suggestions with regard to numerous accessories to roadways which might well be made of concrete, and the following hints are submitted in the hope and belief that they will be of interest to the reader. Pavements.—Modern requirements demand that the ideal footpath or pavement shall be smooth without being slippery, even, durable, clean and unaffected by climatic conditions. These requirements are met in a striking manner by concrete, provided that the material itself is of the first quality, and that the job be carried out in an intelligent and workmanlike manner. Little, however, need be said here about concrete footpaths, since these, either in the form of slabs or concrete laid in situ, are rapidly replacing those of other materials, and they have been so long before the public that their strength, durability and general efficiency have been convincingly proved. Kerbs and Channelling.—This subject, a very important one, has been fully dealt with in Chapter VII. Fig. 127, showing a tree-guard for pavements, illustrates another use for concrete as a substitute for iron. As will be seen from the photograph the tree-guard is in the form of lattice work, each bar of which is reinforced by a single steel rod. Reference has already been made in Chapter VII to the pavement gutters produced in concrete by the Aylesbury Borough Council. Culverts.—In connection with rural roads concrete culverts are coming into general favour. If constructed in situ, they should be built during the dry season, if possible, or the watei’ may be diverted during their construction by building a dam above the culvert and conveying the water away from the work by means of temporary troughs or pipes. A method often adopted is that of employing pre-cast culvert blocks or half-pipes, which, when cemented together, form the culvert. No reinforcement is used in structures of this nature. Fig. 129 is an illustration of this type of culvert. Sewer Pipes and Water Mains.—Considerable economies can be effected and increased efficiency secured by the use of concrete sewer pipes and water mains. These are being adopted here and in various parts of the world with great success. Concrete pipes are usually made either in vertical iron moulds, or are cast on the centrifugal method in horizontal moulds.