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This historic book may have numerous typos and missing text
Purchasers can download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1881. Excerpt: ... head and Alderney the slope of the rabble mound on the harbor side is only about 1J to 1. At Cherbourg it is 1 to 1, and at Leghorn the large concrete blocks are found to be stable at a slope of $ to 1. By a very little care in selection, the thrust of a rubble filling may be reduced to a fraction of that arising from bad material, and indeed in theordinary run of fishing piers in the North of Scotland, however great the height, the face wall of the rubble-hearted pier consists simply of stones from 3 to 4 feet in depth, laid dry to a batter of about 1 in 5. The north-east pier at Seham, again, has an inner wall 25 feet high, battering 1J inch to the foot, and only 5 feet thick, and many similar examples are to be found at other points of the coast. The most cursory examination of cases of failure cited above will serve to justify the statement that the numerous dockwall failures do not afford any direct evidence as to the actual lateral pressure of earthwork. Thus, remembering General Burgoyne''s battering wall, only 17 per cent. of the height in thickness, supported the heavy sodden filling at its back, no calculation is required to show that the 32 and 45 per cent. Southampton Dock counterforted wall, the 42 per cent. Avonmouth Dock wall, the 36 per cent. West India Dock wall, the 50 per cent. Belfast Harbor wall, and the 30 per cent. Victoria Dock wall, would all have stood perfectly had the foundation been rock, as in the instances of General Burgoyne''s experimental walls, instead of the mud, clay, and silt which it actually was. Not only the strength, but the type of cross-section, is singularly indicative of the small influence which theory and experiment have exercised upon the design of dock walls. If the early theorists and experimentalists were ...
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