El Puerto Del Mediterraneo

Breakwaters. For the breakwaters several proposals have been worked out. As the depth of water on which the breakwaters have to be built is from 50 to 65 ft., and experience has shown that the effect of waves may here be very considerable, we have paid special attention to the construction of these breakwaters. The determining points of view in the designs have been that the units of which the breakwaters are composed should be as large as possible and be of the full width of the struc- ture, so that longitudinal joints are avoided. Then the connection between the individual units and between the latter and the bottom must be as efficient as possible in order to form a continuous structure able to resist powerful attacks from the waves. The breakwaters are composed of hollow units of reinforced concrete, which are towed to the site and then sunk into position on a bed of rubble, and filled with concrete, stone and sand. The units are placed one outside of another as the construction proceeds. Owing to the difficulty in levelling the foundation here on the exposed coast the units are of a spe- special construction allowing the levelling to be reduced to a minimum. The constructions are formed in such a manner that ships may lie along the inner side of the breakwaters which cer- tainly will be an advantage here in the outer harbour of Barcelona’s Free Port. Inner Harbour. The harbour is composed of a special commercial harbour, an industrial harbour, basins for wharves with docks and launching ways etc.; and separate basins are provided with quays for coal, and there are special quays for grain with silos, mills and plants belonging thereto. Refrigerator houses are provided for storage of victuals. Finally the quarantine harbour may be mentioned, basins for tugboats, the floating equipment of the harbour as well as dry-docks, ship-building ways and docks etc. In the commercial harbour the depth of the outer basins is 12 m (39 ft.); in the inner basins the depth may be somewhat less, for instance 10 m (33 ft.). In the industrial basins the depth will be determined by the requirements of the various industries. For the quays of the commercial harbour one-story and two-story warehouses have been designed, as well as six-story magazine buildings. The warehouses and magazine buildings are constructed as reinforced-concrete framed structures with curtain walls of brickwork and foundations of reinforced-concrete piles. The grain silos and mills are similarly of reinforced concrete. A very important feature is the equipment of the harbour with cranes and mechanical conveyors enabling the ships to be loaded or unloaded in shortest possible time, so as to reduce the lay days to a minimum. Here we have proposed various types of ordinary quay cranes as well as special cranes for heavy goods, coal cranes and finally various systems of wharf cranes. Besides these larger cranes minor portable electric cranes as well as electro-cars, portable conveyor bands etc. are supposed to be used especially in the warehouses and magazines, and finally elevators in the buildings. 19