Engineering and Contracting . ccom-lilishod by means of two specially con-structed 500 ton hydraulic jacks. After the^] was landed on the wooden blocking. Before the last, of these shims was re-moved the span was landed on the oakblocking, the jacks released and one ormore sections of cast iron blocking re-moved, the jacks pumped up, shims re-placed, and the operation repeated until allthe cast iron blocking had been removed,when one of the concrete-filled cylinderswas taken out, the casting and shims re-placed, and so on until the span was land-ea on its permanent shoes. The oak block-ing
Engineering and Contracting . ccom-lilishod by means of two specially con-structed 500 ton hydraulic jacks. After the^] was landed on the wooden blocking. Before the last, of these shims was re-moved the span was landed on the oakblocking, the jacks released and one ormore sections of cast iron blocking re-moved, the jacks pumped up, shims re-placed, and the operation repeated until allthe cast iron blocking had been removed,when one of the concrete-filled cylinderswas taken out, the casting and shims re-placed, and so on until the span was land-ea on its permanent shoes. The oak block-ing was also removed as the span was low-ered, the top of it being kept high enoughto free the jacks while shims were beingadjusted. When the span had been lowered about 4ft. at one end, the jacks were transferredto the other and similar operations carriedout there. That end, however, was low-ered right down to tlie shoes before thejacks were returned to the end first low-ered. The bridge was designed by the bridge MfitJ^^^x^^^^. /4ff Enqr Traveler Used in Erecting French River Bridge of C. P. Ry. the last section was reached it was re-moved, and the forward block secured bythe pill direct to the box girder. When everything was in readiness, onthe evening of October 2], 1907, the scow-was pumped out by means of the centrifu-gal pump, until the span was raised off theblocking. When this occurred it was foundthat there still remained a foot of water inthe scow, showing that an ample margin ofbuoyancy had been allowed. At 8 a. m. onthe 28th the engine was started, and withthe assistance of a slight shove from two40-ton hydraulic jacks the large span start-ed on its way, moving on the well greasedskidding rails at the rate of 4 to 6 ft. perminute. Considerable time was lost owingto the inability of the small boiler of thehoisting engine to keep up a sufficient steampressure and also in the overhauling of thevery heavy tackle. The actual time occupied in moving thespan was 3 hours, and
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Keywords: ., bookcentury1900, bookdecade1900, bookpublisherchicago, bookyear19
