A Treatise On The Principles And Practice Of Dock Engineering

TIMBER WHARF AT DUNDEE. 293 70 feet from the quay face. The jetties are 20 feet and the wharf 15 feet wide. All the timber work is of pitchpine except the fenders, which are of American rock elm. The coping timber is protected by a sheathing of malleable iron, 2| feet broad and J inch thick. The pitchpine was creosoted with 4 Ibs. of creosote per cubic foot, which, owing to the density of the timber, was with difficulty forced into it. Twenty-five mooring bollard piles, 48 feet long, were driven and secured to the main framing of the jetties and quays, and litted on the top with cast-iron bollard caps. The bays of piling of the jetties are 9 feet apart, and of the quays between the jetties, 8 feet. The slopes behind the jetty quays down to the lowest low- water mark are protected with 16-inch rubble whinstone pitching, laid on a 6-inch bed of gravel. A quay wall, 80 feet in length, and three piers and foundations for supporting a 100-ton derrick crane were constructed of conerete in the tide- way, within two rows of sheeting piles, 38 feet long. The three crane piers are raised 22 feet above the quay level; they are 20 feet square at the base and 17| feet square at the top, and have wrought-iron holding-down bolts. Plate castings are built into the piers for securing the granite seats and the foundation castings of the crane. Along both sides of the derrick crane seat, a timber wharf, very economical and serviceable in form where the depth of water in front of the quay is not greater than about 10 feet at ordinary low water, was constructed for a total length of 220 feet. Forty- five bays of supporting piles, in front, and stay piles, four in each bay, behind, were driven, 5 feet apart, along the wharf. A row of sheeting piles, 22 feet long and 7 inches thick, was driven along the face of the wharf. For a depth of 14 feet below the coping level, close 4-inch planking was spiked to the back of the front row of supporting piles, and a coping timber, 18 inches by 10 inches, was secured along the quay face to the pile-heads. The wharfing was tied back by iron bolts to the stay piles, and the space imme- diately behind the face-work was filled in with ashes, brick rubbish, &c. The cost of such a wharf facing amounts to between £10 and £12 per lineal foot of frontage. Timber Wharf at Dundee.* The landing wharf (figs. 239 and 240) at present in use for the discharge of steamers, and available at any time of the tide for vessels whose draught is too great to admit of entrance into the docks, has a length of 2,800 feet, and is provided with shed accommodation at the rear to the extent of 24,650 square yards. It is 12 feet 6 inches in width, is constructed of two rows of main piles, 9 feet apart centre to centre, with sheeting between the piles of the first row, and is tied back by iron tie-rods ^ inch diameter and 50 feet long. There are bollards along the face of the wharf, 18 feet apart, and numerous ladders down to low-water level. The timber wharf being of * Buchanan on “ The Port of Dundee,” Min. Proc. Inst. C.E., vol. exlix.