Transactions of the American Society of Civil Engineers, vol. LXX, Dec. 1910 eBook

This eBook from the Gutenberg Project consists of approximately 10 pages of information about Transactions of the American Society of Civil Engineers, vol. LXX, Dec. 1910.

Transactions of the American Society of Civil Engineers, vol. LXX, Dec. 1910 eBook

This eBook from the Gutenberg Project consists of approximately 10 pages of information about Transactions of the American Society of Civil Engineers, vol. LXX, Dec. 1910.

Unfortunately, the work was let so late in the summer, and the restrictions as to seasoning the concrete were enforced so rigidly, that the work of setting the caissons could not be commenced until November 11th, thus the entire construction was forced into the very bad weather of the late fall and early winter.  As this involved very rough water and much snow and wind, the work was greatly delayed, and was not completed until the middle of January.  The cost of the entire dock was about $14,000.

The writer believes that the cost was much less than for masonry piers by any other method of construction, under the existing circumstances of wind, tide, and exposure.

It would seem that for many highway bridges of short span, causeways, and similar structures, the use of similar caissons would prove economical and permanent, and that they might be used very largely to the exclusion of cribwork, which, after a decade or so, becomes a source of constant maintenance charges, besides never presenting an attractive appearance.  Finally, in bridges requiring the most rigid foundations, these caissons might readily be used as substitutes for open wooden caissons, sunk on a prepared foundation of whatever nature, and still be capable of incorporation into the finished structure.

DISCUSSION

William Arthur Payne, M. Am.  Soc.  C. E. (by letter).—­On the arrival of the first barge load of brick, to be used in building a residence on the estate to which this pier belongs, a severe northwest wind blew for two days, after the boat was moored alongside, directly against the head of the pier and the side of the boat.  The effect on the pier was to crush the fender piles and cause a settlement of one of the caissons at the pier head on the west end.  The caisson was knocked slightly out of alignment, and a settlement toward the west was observable.

The writer believes that this was caused by the pounding of the brick barge on the sand bottom on which the caissons rest, during half tide, the boat being raised from the bottom on a roller, and striking when the roller had passed.  In order to protect the pier and avoid the bumping of barges against it, three groups of piles were driven about 8 ft. beyond the end, a secondary platform was built between these and the stringer of the pier, and arranged so that it would slide on the stringer in case of movement of the piles.  This secondary platform is particularly advantageous in the handling of material, as the height of the dock was found to be excessive for passing up brick and cement.  For handling material after it is deposited on the dock, an industrial railroad has been built.  At the shore end of this railroad, brick and cement are dumped into wagons, in which they are carried up the hill to the house.

Eugene Klapp, M. AmSoc.  C. E. (by letter).—­The injury done to the piers, as reported by Mr. Payne, is not to be wondered at.  The pier was primarily built for a yacht landing, and, on account of the shoal water conditions, excepting at extreme high tide, it was mostly to be used by tenders and launches from larger yachts.  It was thought that at high water the large steam yachts might be able to come alongside.

Copyrights
Project Gutenberg
Transactions of the American Society of Civil Engineers, vol. LXX, Dec. 1910 from Project Gutenberg. Public domain.