MILITARY BRIDGES

Poverty Bay Herald, Volume LXIII, Issue 18975, 27 March 1936, Page 14

MILITARY BRIDGES

MODERN -METHODS EXPLAINED BY MODELS ___ From earliest times the problems of bridging have played an important part in military campaigns. Some authorities claim that Semiramis carried sectional, boats for crossing wide rivers during an expedition she made to India about 800 B.C. To-day the bridging problem before the military engineer is becoming even more difficult. There are two reasons for 'this. First, owing to ever-increasing mechanisation the loads to be carried have become much heavier, Heavy lorries, tanks, and other tracked vehicles which now accompany an army were not in existence 20 years ago. Secondly, this same mechanisation has greatly increased the speed of movement of an army, and thus bridges must be built more rapidly if full advantage is to be gained from this power of rapid movement. One of the aims of the military engineer since the Great War has been to design bridges which are stronger and yet more rapidly erected than before. The British Army has an added difficulty in that its bridges must be suitable for a campaign in any part of the world, and must withstand varied climatic conditions. STANDABD EQUIPMENT These factors have brought the authorities to the conclusion that the army must depend more on standard bridging equipment, carried in the field, than on improvising bridges from material collected on the proposed site. In consequence the British Army is now being equipped with several kinds of standard military bridges. Ultimately there will be about six standardised types of bridge equipment These will range from light foot bridges, which can be assembled under cover and then carried forward and launched complete, to heavy steel truss. bridges for the back areas, for carrying tanks and other heavy loads.. Three types of floating equipment have been adopted; the foot or "assault" bridge, already mentioned, a new folding boat equipment, and a new design of the old wartime pontoon bridge. Those familiar witfi the wartime pontoon will see many radical charges. For instance, the pontoons have been decked ■■-.over, while many of the timber parts have been replaced by a special chrome steel. Another, new type is the box girder bridge, of which there are two sizes, designated as "small" and "large." These work on the principle of building up girders by joining together a series of latticed steel boxes. By varying the number of boxes the length of the girder is made to suit the gap to be bridged. New Zealand Engineer Territorial units are being supplied with "assault" bridging, which is being made in Wellington, but they have not at present, any of the other modern equipment. However, they have just been supplied with scale models of the new folding boat and pontoon equipments.