Pittsburgh Bridges at the Point
Historic American Engineering Record PA-3, PA-4, PA-5
page 9
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The Point Bridge II: 1927
As a result of such public agitation the County Department of Public Works began to study the situation and in due course the County Engineers, V. R. Covell, C. M. Reppert, and their associates completed a number of general designs for the bridge on the span lengths and clearances which the government has approved. (28) A committee of engineers then made a study of the several plans. Meanwhile funds for the new bridge were provided --a sum of $2,325,000 --in an Allegheny County people's bond issue and a discussion continued among City and County officials as to which plan should be adopted. A bridge at right-angles to the old bridge was considered but was rejected because approaches at either side would be too difficult. (29)
Finally plans for a bridge that would run parallel to the old bridge were approved by the County Commissioners. To avoid obstructions in the river channel a through-cantilever type of construction was adopted. The total length of the bridge was to be 1330 feet with approaches. The main span clearance for river traffic was 430 feet and the span supported as well a 38 foot roadway, allowing four lanes of traffic and two 12 foot sidewalks. (30)
A preliminary perspective sketch for the new bridge was published in the local architectural magazine, The Charette V:6 (June, 1925), frontispiece, and in the same magazine another sketch of the final design with a brief article appeared, V:10 (October, 1925), frontispiece. The design also carried the approval of the Pittsburgh Art Commission, who had recommended that the cantilever, in which both the top and bottom chords curve downward, should be given a convex outline to harmonize with the nearby Manchester Bridge.(31) The architect for the bridge was Stanley L. Roush. (32)
Work on the new bridge began in April, 1925, when Sprague and Henwood, core-drilling contractors started test borings to determine what foundation conditions would be encountered in the sinking of the two main piers. (33) In June, 1925 the contract for the piers and the approach; was awarded to the Dravo Construction Company of Pittsburgh for $591,195. (34) In December of the same year the contract for the steel superstructure was awarded to the Fort Pitt Bridge Works of Pittsburgh for $907,685. (35) The engineer in charge of design for the Department of Public Works was George S. Richardson. (36) Final working drawings for the bridge were completed in 5 September, 1925.
On 21 July, 1925, the Pittsburgh Gazette-Times reported that "the first caisson for one of the two river piers of the new Point Bridge was towed up the Ohio River from the Neville Island plant of the Dravo Construction Company to the bridge site. It will be filled with concrete and sunk in the river bed at the pier site, enabling workmen to construct the pier below water line. The laying of the substructure is to be completed by 1 June, 1926 and erection of the superstructure will start later."
In November it was reported that "the masonry of the new Point Bridge has just been completed by the Dravo Construction Company of Pittsburgh at a cost of about $657,000. Steel erection has been going on since early summer beginning on the north side where the masonry was first completed, and at the present time most of the steel work is in place. Fort Pitt Bridge Works is fabricating and erecting the superstructure. Present expectations are that the steel work will be finished in January 1927 and that the bridge will be open early next year." (37)
The construction of the superstructure was something of an engineering hybrid, that is, a cantilever arch-truss, with a suspended central span. The three primary elements comprising this type of construction are an anchor arm, cantilever arm and suspended span. The bridge is anchored in tension to the shore abutments and pivots about the river piers. The central span is hung from the arch construction which cantilevers out from each pier. The portals compared with the ornamental delicacies of those of the nearby Manchester Bridge were stark and brutal, being composed of unadorned steel plates, but nonetheless impressive. Technology was totally triumphed, having cast off all historical masks. The day of the adorned bridge portal has vanished.
On 20 June, 1927, the new bridge was opened to traffic in a ceremony in which some 2500 persons took part. The completed span was turned over to the people of Allegheny County by the Commissioners who accepted it from Norman F. Brown, the Director of Public Works. (38)
For a time the new bridge was sufficient for all traffic needs at the Point, but after 1945 with the development of the new Point Park scheme and the increasing motor traffic to the South Hills beyond the Monongahela, it became apparent that the days of the cantilever span were numbered and it too was closed in June 1959. Truly, the days of a modern highway bridge are as grass, but the last years and death of the Point Bridge are so intimately connected with those of its fellow Point span -- the Manchester Bridge -- that the two will be discussed together later.
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