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appears applied arrangement beams bottom breaking weight bridge Britannia calculations carried cells cellular completed compression considerable considered construction Conway tube crushing cylindrical dear Sir Deflection Deflection in inches depth determined distance distribution double doubt drawings elliptical equal experiments facts feet force formula further gave girder give given greater Hodgkinson important inches increased iron joints laid letter load lower Manchester material matter means ments middle model tube nearly necessary object observed obtained plates platform position possible powers present principle progress proportions proposed raising rectangular reference Remarks removed rendered resistance respects riveted Robert Stephenson shackle shown side square strain strength structure sufficient suggestions supports suspended sustain taken thickness tion tons top and bottom top side transverse tube Ultimate upper weight whole William Fairbairn
الصفحة 41 - On consulting the above table, it will be found that the results, as respects strength, are of a higher order than those obtained from the cylindrical and elliptical tubes ; and particularly those constructed with stronger plates on the top side, which, in almost every experiment where the thin side was uppermost, gave signs of weakness in that part. Some curious and interesting phenomena presented themselves in these experiments, — many of them are anomalous to our preconceived notions of the...
الصفحة 44 - In fact, it should be a huge sheet-iron hollow girder, of sufficient strength and stiffness to sustain those weights ; and provided the parts are well proportioned, and the plates properly riveted, you may strip off the chains, and leave it as a useful monument of the enterprise and energy of the age in which it was constructed.
الصفحة 38 - Immediately on opening the suspension bridge for railway traffic, the undulations into which the roadway was thrown, by the inevitable unequal distribution of the weight of the train upon it, were such as to threaten the instant downfall of the whole structure.
الصفحة 42 - Nos. 17 and 18 are of the same character, where the top plate is as near as possible double the thickness of the bottom. In these experiments the tube was first crippled by doubling up the thin plate on the top side, which was done with a weight of 3788 Ibs.
الصفحة 173 - ... be entrusted to those gentlemen, whose constant presence during the building of the first tube had rendered them thoroughly acquainted with the whole details of the work. By such an arrangement, moreover, the Company would save the amount which had hitherto been paid for my services, and I should be enabled to devote my time to other pursuits, which I had neglected for this work, and which now urgently demanded my attention. This was one reason for my retirement ; but what chiefly led me to this...
الصفحة iii - An Account of the Construction of the Britannia and Conway Tubular Bridges. With a complete History of their Progress...
الصفحة 14 - These experiments led to the trial of the rectangular form of tube with a corrugated top, the superior strength of which decided me to adopt that cellular structure of the top of the tube which ultimately merged into a single row of rectangular cells.
الصفحة 235 - It will be observed that the whole of these experiments indicated weakness on the top side of the tube, which, in almost every case, was greatly distorted by the force of compression acting in that direction. It is probable that those of the cylindrical form would have yielded in like manner, had the riveting at the joints been equally perfect on the lower side of the tube. This was not, however, the case, and hence arise the causes of rupture at that part.
الصفحة 47 - ... being the same. 2. To obtain the strength of similar tubes. 3. To find the strength of tubes of various forms of section in the middle, and to furnish means of judging of the proper proportions of the metal in the bottom, top, and sides of the tube. 4. To ascertain the relative strength...
الصفحة 36 - ... the beam. We have arrived therefore at a fact having a most important bearing upon the construction of the tube ; viz. that rigidity and strength are best obtained by throwing the greatest thickness of material into the upper side. Another instructive lesson which the experiments have disclosed is, that the rectangular tube is by far the strongest, and that the circular and elliptical should be discarded altogether.