❤️ Tay Bridge disaster 🦒

"The Tay Bridge Disaster occurred during a violent storm on Sunday 28 December 1879, when the first Tay Rail Bridge collapsed as a train from Burntisland to Dundee passed over it, killing all aboard. The bridge—designed by Sir Thomas Bouch—used lattice girders supported by iron piers, with cast iron columns and wrought iron cross-bracing. The piers were narrower and their cross-bracing was less extensive and robust than on previous similar designs by Bouch. Bouch had sought expert advice on wind loading when designing a proposed rail bridge over the Firth of Forth; as a result of that advice he had made no explicit allowance for wind loading in the design of the Tay Bridge. There were other flaws in detailed design, in maintenance, and in quality control of castings, all of which were, at least in part, Bouch's responsibility. Bouch died less than a year after the disaster, his reputation ruined. Future British bridge designs had to allow for wind loadings of up to . Bouch's design for the Forth Bridge was not used. Bridge Original Tay Bridge from the north Construction began in 1871 of a bridge to be supported by brick piers resting on bedrock. Trial borings had shown the bedrock to lie at no great depth under the river. At either end of the bridge, the bridge girders were deck trusses, the tops of which were level with the pier tops, with the single track railway running on top. However, in the centre section of the bridge (the "high girders") the bridge girders ran as through trusses above the pier tops (with the railway inside them) in order to give the required clearance to allow passage of sailing ships to Perth.Bridge design is described (intermittently) in Minutes of Evidence pp. 241–271(H Law); the bridge design process in Minutes of Evidence pp. 398–408 (Sir Thomas Bouch) The bedrock lay much deeper than the trial borings had shown, and Bouch had to redesign the bridge, with fewer piers and correspondingly longer span girders. The pier foundations were now constructed by sinking brick-lined wrought-iron caissons onto the riverbed, and filling these with concrete. To reduce the weight these had to support, Bouch used open-lattice iron skeleton piers: each pier had multiple cast-iron columns taking the weight of the bridging girders. Wrought iron horizontal braces and diagonal tiebars linked the columns in each pier to provide rigidity and stability. The basic concept was well known, but for the Tay Bridge, the pier dimensions were constrained by the caisson. For the higher portion of the bridge, there were thirteen girder spans. In order to accommodate thermal expansion, at only three of their fourteen piers was there a fixed connection from the pier to the girders. There were therefore three divisions of linked high girder spans, the spans in each division being structurally connected to each other, but not to neighbouring spans in other divisions.Minutes of Evidence pp. 241–271(H Law) The southern and central divisions were nearly level, but the northern division descended towards Dundee at gradients of up to 1 in 73.Report of Court of Inquiry – Appendix 3 The bridge was built by Hopkin Gilkes and Company, a Middlesbrough company which had worked previously with Bouch on iron viaducts. Gilkes, having first intended to produce all ironwork on Teesside, used a foundry at Wormit to produce the cast-iron components, and to carry out limited post-casting machining. Gilkes were in some financial difficulty; they ceased trading in 1880, but had begun liquidation in May 1879, before the disaster. Bouch's brother had been a director of Gilkes, and all three had been colleagues on the Stockton and Darlington 30 years previously; on Gilkes's death in January 1876, Bouch had inherited shares valued at £35,000 but also owed for a guarantee of £100,000 of Gilkes borrowings and been unable to extricate himself.Mins of Ev p. 440 (Sir T Bouch) The change in design increased cost and necessitated delay, intensified after two of the high girders fell when being lifted into place in February 1877. The first engine crossed the bridge in September, 1877. A Board of Trade inspection was conducted over three days of good weather in February 1878; the bridge was passed for use by passenger traffic, subject to a speed limit. The inspection report noted: > When again visiting the spot I should wish, if possible, to have an > opportunity of observing the effects of high wind when a train of carriages > is running over the bridge. The bridge was opened for passenger services on 1 June 1878. Bouch was knighted in June 1879 soon after Queen Victoria had used the bridge. Disaster On the evening of Sunday 28 December 1879, a violent storm (10 to 11 on the Beaufort scale) was blowing virtually at right angles to the bridge.Mins of Ev p. 24 (Captain Scott) Witnesses said the storm was as bad as any they had seen in the 20–30 years they had lived in the area;Mins of Ev p. 15 (James Black Lawson)Mins of Ev p. 33 (Capt John Greig) one called it a 'hurricane', as bad as a typhoon he had seen in the China Sea.Mins of Ev p. 18 (George Clark) The wind speed was measured at Glasgow – (averaged over an hour) – and Aberdeen, but not at Dundee. Higher windspeeds were recorded over shorter intervals, but at the inquiry an expert witness warned of their unreliability, and declined to estimate conditions at Dundee from readings taken elsewhere.Mins of Ev p. 392 (Robert Henry Scott, MA FRS, Secretary to the Meteorological Council) One modern interpretation of available information suggests winds were gusting to . Use of the bridge was restricted to one train at a time by a signalling block system using a baton as a token. At 7:13 p.m. a train from Burntisland (consisting of a 4-4-0 locomotive, its tender, five passenger carriages, and a luggage van, slowed to pick up the baton from the signal cabin at the south end of the bridge, then headed out onto the bridge, picking up speed. The signalman turned away to log this and then tended the cabin fire, but a friend present in the cabin watched the train: when it got about from the cabin he saw sparks flying from the wheels on the east side. He had also seen this on the previous train.Mins of Ev p. 79 (John Black) During the inquiry, John Black testified that the wind was pushing the wheel flanges into contact with the running rail. Black explained that the guard rails protecting against derailment were slightly higher than and inboard of the running rails. This arrangement would catch the good wheel where derailment was by disintegration of a wheel, which was a real risk before steel wheels, and had occurred in the Shipton-on-Cherwell train crash on Christmas Eve 1874. The sparks continued for no more than three minutes, by which time the train was in the high girders.Mins of Ev p. 7 (John Watt) At that point "there was a sudden bright flash of light, and in an instant there was total darkness, the tail lamps of the train, the sparks and the flash of light all ... disappearing at the same instant." The signalman saw none of this and did not believe it when told about it. When the train failed to appear on the line off the bridge into Dundee he tried to talk to the signal cabin at the north end of the bridge, but found that all communication with it had been lost.Mins of Ev p. 5 (Thomas Barclay) Not only was the train in the river, but so were the high girders, and much of the ironwork of their supporting piers.Photographs of the damaged piers and of recovered wreckage are accessible at Divers exploring the wreckage later found the train still within the girders, with the engine in the fifth span of the southern 5-span division.Mins of Ev p. 39 (Edward Simpson) There were no survivors; only 46 bodies were recovered but there were 59 known victims. Fifty-six tickets for Dundee had been collected from passengers on the train before crossing the bridge; allowing for season ticket holders, tickets for other destinations, and for railway employees, 74 or 75 people were believed to have been on the train.Report of the Court of Inquiry page 9 It has been suggested that there were no unknown victims and that the higher figure arises from double-counting in an early newspaper report, but the inquiry did not take its casualty figures from the Dundee Courier; it took sworn evidence and did its own sums. File:North British Railway locomotive 224.jpgThe locomotive was dropped during retrieval, but eventually recovered and returned to service. File:Part of the train salvaged from the Tay 02.jpgThe left front of the recovered locomotive tender File:Part of the train salvaged from the Tay.jpgRight side of the recovered locomotive tender File:Wreckage salvaged from the collapsed Tay Bridge 06.jpgTwo wagons holding wreckage salvaged from the train File:Wreckage salvaged from the collapsed Tay Bridge 05.jpgOpposite view of previous view showing two wagons holding salvaged wreckage File:Wreckage salvaged from the collapsed Tay Bridge 09.jpgSalvaged wreckage from the train File:Wreckage salvaged from the collapsed Tay Bridge 13.jpgSalvaged wreckage from the train File:Section of fallen girders.jpgFallen girders with remains of a wooden train carriage Court of inquiry =Evidence= A court of Inquiry (a judicial enquiry under Section 7 of the Regulation of Railways Act 1871 "into the causes of, and circumstances attending" the accident) was immediately set up: Henry Cadogan Rothery, Commissioner of Wrecks, presided, supported by Colonel Yolland (Inspector of Railways) and William Henry Barlow, President of the Institution of Civil Engineers. By 3 January 1880, they were taking evidence in Dundee; they then appointed Henry Law (a qualified civil engineer) to undertake detailed investigations. Whilst awaiting his report they held further hearings in Dundee (26 February – 3 March); having got it they sat at Westminster (19 April – 8 May) to consider the engineering aspects of the collapse.Report of the Court of Inquiry, page 3 By then railway, contractor and designer had separate legal representation, and the North British Railway (NBR) had sought independent advice (from James Brunlees and John Cochrane, both engineers with extensive experience of major cast-iron structures). The terms of reference did not specify the underlying purpose of the inquiry – to prevent a repetition, to allocate blame, to apportion liability or culpability, or to establish what precisely had happened. This led to difficulties (culminating in clashes) during the Westminster sessions and when the court reported their findings at the end of June, there was both an Inquiry Report signed by Barlow and Yolland and a minority report by Rothery. Other eyewitnesses Two witnesses, viewing the high girders from the north almost end-on, had seen the lights of the train as far as the 3rd–4th high girder, when they disappeared; this was followed by three flashes from the high girders north of the train. One witness said these advanced to the north end of the high girders with about 15 seconds between first and last;Mins of Ev p. 19 (Alexander Maxwell) the other that they were all at the north end, with less time between.Mins of Ev p. 19 (William Abercrombie Clark) A third witness had seen "a mass of fire fall from the bridge" at the north end of the high girders.Mins of Ev p. 16 (James Black Lawson) A fourth said he had seen a girder fall into the river at the north end of the high girders, then a light had briefly appeared in the southern high girders, disappearing when another girder fell; he made no mention of fire or flashes.Mins of Ev p. 53 (Peter Barron) 'Ex-Provost' Robertson had a good view of most of the bridge from his house in Newport-on-Tay, but other buildings blocked his view of the southern high girders. He had seen the train move onto the bridge; then in the northern high girders, before the train could have reached them, he saw "two columns of spray illuminated with the light, first one flash and then another" and could no longer see the lights on the bridge; the only inference he could draw was that the lit columns of spray – slanting from north to south at about 75 degrees – were areas of spray lit up by the bridge lights as it turned over.Mins of Ev pp. 58–59 (William Robertson) How the bridge was used – speed of trains and oscillation of bridge Ex-provost Robertson had bought a season ticket between Dundee and Newport at the start of November, and became concerned about the speed of north-bound local trains through the high girders, which had been causing perceptible vibration, both vertical and lateral. After complaining on three occasions to the stationmaster at Dundee, with no effect on train speed, after mid-December he had used his season ticket to travel south only, using the ferry for north-bound crossings. Robertson had timed the train with his pocket watch, and to give the railway the benefit of the doubt he had rounded up to the nearest five seconds. The measured time through the girders () was normally 65 or 60 seconds, but twice it had been 50 seconds. When observing from the shore, he had measured 80 seconds for trains travelling through the girders, but not on any train he had travelled on. North-bound local trains were often held up to avoid delaying expresses, and then made up time while travelling over the bridge. The gradient onto the bridge at the northern end prevented similar high speeds on south-bound locals. Robertson said that the movement he observed was hard to quantify, although the lateral movement, which was probably , was definitely due to the bridge, not the train, and the effect was more marked at high speed. Four other train passengers supported Robertson's timings but only one had noticed any movement of the bridge.Mins of Ev (pp. 65–72): Thomas Downing Baxter (speed only), George Thomas Hume (speed only), Alexander Hutchinson (speed and movement) and (p. 88) Dr James Miller (speed only) The Dundee stationmaster had passed Robertson's complaint about speed (he had been unaware of any concern about oscillation) on to the drivers, and then checked times from cabin to cabin (at either end of the bridge the train was travelling slowly to pick up or hand over the baton). However he had never checked speed through the high girders.Mins of Ev pp. 72–76 (James Smith) Painters who had worked on the bridge in mid-1879 said that it shook when a train was on it.Mins of Ev pp. 88–97 (David Pirie, Peter Robertson, John Milne, Peter Donegany, David Dale, John Evans) When a train entered the southern high girders the bridge had shaken at the north end, both east–west and, more strongly, up-and-down.Mins of Ev p. 91 (Peter Donegany) The shaking was worse when trains were going faster, which they did: "when the Fife boat was nearly over and the train had only got to the south end of the bridge it was a hard drive".Mins of Ev p. 95 (John Evans) A joiner who had worked on the bridge from May to October 1879 also spoke of a lateral shaking, which was more alarming than the up-and-down motion, and greatest at the southern junction between the high girders and the low girders. He was unwilling to quantify the amplitude of motion, but when pressed he offered . When pressed further he would only say that it was distinct, large, and visible.Mins of Ev pp. 101–103 (Alexander Stewart) One of the painters' foremen, however, said the only motion he had seen had been north–south, and that this had been less than .Mins of Ev pp. 124–125 (Edward Simpson) How the bridge was maintained – chattering ties and cracked columns The North British Railway maintained the tracks, but it retained Bouch to supervise maintenance of the bridge. He appointed Henry Noble as his bridge inspector.Mins of Ev pp. 215–225 (Henry Abel Noble) Noble, who was a bricklayer, not an engineer, had worked for Bouch on the construction of the bridge.Mins of Ev pp. 409–410 (Sir Thomas Bouch) Whilst checking the pier foundations to see if the river bed was being scoured from around them, Noble had become aware that some diagonal tie bars were 'chattering', and in October 1878 had begun remedying this. Diagonal bracing was by flat bars running from one lug at a column section top to two sling plates bolted to a lug at the base of the equivalent section on an adjacent column. The bar and sling plates all had a matching longitudinal slot in them. The tie bar was placed between the sling plates with all three slots aligned and overlapping, and then a gib was driven through all three slots and secured. Two "cotters" (metal wedges) were then positioned to fill the rest of the slot overlap, and driven in hard to put the tie under tension. Noble had assumed the cotters were too small and had not been driven up hard in the first place, but on the chattering ties the cotters were loose, and even if driven fully in would not fill the slot and put the bar under tension. By fitting an additional packing piece between loose cotters and driving the cotters in, Noble had re-tightened loose ties and stopped them chattering. There were over 4,000 gib and cotter joints on the bridge, but Noble said that only about 100 had had to be re-tensioned, most in October–November 1878. On his last check in December 1879, only two ties had needed attention, both on piers north of the high girders. Noble had found cracks in four column sections – one under the high girders, three to the north of them – which had then been bound with wrought iron hoops. Noble had consulted Bouch about the cracked columns, but not the chattering ties.Mins of Ev p. 219 (Henry Abel Noble), confirmed by pp. 427–429 (Sir Thomas Bouch) How the bridge was built – the Wormit foundry The workers at the Wormit foundry complained that the columns had been cast using 'Cleveland iron', which always had scum on it—it was less easy to cast than 'good Scotch metal'Mins of Ev p. 103 (Richard Baird) and more likely to give defective castings. Moulds were damped with salt water,Mins of Ev p. 107 (Richard Baird) cores were inadequately fastened, and moved, giving uneven column wall thickness.Mins of Ev p. 119 (David Hutton) The foundry foreman explained that where lugs had been imperfectly cast; the missing metal was added by 'burning on'. If a casting had blowholes or other casting defects considered to be minor faults, they were filled with 'Beaumont egg' (which the foreman kept a stock of for that purpose) and the casting was used.Mins of Ev pp. 144–152 (Fergus Fergusson) How the bridge was built – management and inspection Gilkes' site staff were inherited from the previous contractor. Under the resident engineer there were seven subordinates including a foundry manager. The original foundry manager left before most of the high girders pier column sections were cast. His replacement was also supervising erection of the bridge, and had no previous experience of supervising foundry work.Mins of Ev p. 164 (Gerrit Willem Camphuis) He was aware of 'burning on',Mins of Ev pp. 158–163 (Gerrit Willem Camphuis) but the use of Beaumont egg had been hidden from him by the foreman.Mins of Ev p. 208 (Alexander Milne) and p. 211 (John Gibb) When shown defects in bridge castings, he said he would not have passed the affected columns for use, nor would he have passed columns with noticeably uneven wall thickness. According to his predecessor, burning-on had only been carried out on temporary 'lifting columns', which were used to allow the girders to be lifted into place and were not part of the permanent bridge structure.Mins of Ev p. 185 (Frank Beattie) That was on the instructions of the resident engineer,Mins of Ev p. 280 (Albert Groethe) who had little foundry experience either and relied upon the foreman.Mins of Ev p. 298 (Albert Groethe) Whilst the working practices were the responsibility of Gilkes, their contract with NBR provided that all work done by the contractor was subject to the approval of the workmanship by Bouch. Hence Bouch would share the blame for any resulting defective work in the finished bridge. The original foundry foreman, who had been dismissed for drunkenness, vouched for Gilkes personally testing for unevenness in the early castings: "Mr. Gilkes, sometimes once a fortnight and sometimes once a month, would tap a column with a hammer, first on one side and then on the other, and he used to go over most of them in that way sounding them."Mins of Ev p 154 (Hercules Strachan) Bouch had spent over £9,000 on inspection (his total fee was £10,500) but did not produce any witness who had inspected castings on his behalf. Bouch himself had been up about once a week whilst the design was being changed, but "afterwards, when it was all going on, I did not go so often". Bouch kept his own 'resident engineer', William Paterson, who looked after the construction of the bridge, its approaches, the line to Leuchars, and the Newport branch. Paterson was also the engineer of the Perth General Station.Mins of Ev p 418 (Sir Thomas Bouch) Bouch told the court that Paterson's age was 'very much mine' but, in fact, Paterson was 12 years older and, by the time of the Inquiry, paralysed and unable to give evidence.Mins of Ev p. 401 (Sir Thomas Bouch) Another inspector appointed later was by then in South Australia and also unable to give evidence. Gilkes' managers could not vouch for any inspection of castings by Bouch's inspectors.Mins of Ev p. 514 (Edgar Gilkes), p. 370 (Frederick William Reeves) and p. 290 (Albert Groethe) The completed bridge had been inspected on Bouch's behalf for quality of assembly, but that was after the bridge had been painted (though still before the bridge opened, and before the painter witnesses were on it in the summer of 1879), which hid any cracks or signs of burning-on (though the inspector said that, in any case, he would not know those signs on sight).Mins of Ev p. 135 (G Macbeath) Throughout construction, Noble had been looking after foundations and brickwork. "The evidence of the ruins" The bridge after its collapse. Fallen girders, Tay Bridge Henry Law had examined the remains of the bridge; he reported defects in workmanship and design detail. Cochrane and Brunlees, who gave evidence later, largely concurred. Bridge materials Samples of the bridge materials, both cast and wrought iron, were tested by David Kirkaldy, as were a number of bolts, tiebars, and associated lugs. Both the wrought and cast iron had good strength, while the bolts "were of sufficient strength and proper iron".Mins of Ev p. 483 (Dr William Pole) However, both ties and sound lugs failed at loadings of about 20 tons, well below what had been expected. Both ties and lugs were weakened by high local stresses where the bolt bore on them. Four of the fourteen lugs tested were unsound, having failed at lower than expected loadings. Some column top lugs outlasted the wrought iron, but the bottom lugs were significantly weaker.Mins of Ev pp. 303–304 (Henry Law) =Opinions and analysis= Windloading =Windloading assumed in design= Bouch had designed the bridge, assisted in his calculations by Allan Stewart. After the accident Stewart had assisted William Pole in calculating what the bridge should have withstood. On the authority of Stewart they had assumed that the bridge was designed against a wind loading of 'with the usual margin of safety'.p. xiv of Appendix to Report of Inquiry Bouch said that whilst had been discussed, he had been 'guided by the report on the Forth Bridge' to assume and therefore made no special allowance for wind loading.Mins of Ev p. 420 (Sir Thomas Bouch) He was referring to advice given by the Astronomer Royal, Sir George Biddell Airy in 1873 when consulted about Bouch's design for a suspension bridge across the Firth of Forth; that wind pressures as high as might be encountered very locally, but averaged over a span would be a reasonable allowance.Mins of Ev p. 381(Sir George Airy) This advice had been endorsed by a number of eminent engineers. Bouch also mentioned advice given by Yolland in 1869 – that the Board of Trade did not require any special allowance for wind loading for spans less than , whilst noting this was for the design of girders not piers. =Opinions on windloading allowance= Evidence was taken from scientists on the current state of knowledge on wind loading and from engineers on the allowance they made for it. Airy said that the advice given was specific to suspension bridges and the Forth; could act over an entire span of the Tay Bridge and he would now advise designing to (i.e. with the usual margin of safety). The highest pressure measured at Greenwich was ; it would probably go higher in Scotland. Sir George Stokes agreed with Airy that 'catspaws', ripples on the water produced by gusts, could have a width of several hundred yards. Standard wind pressure measurements were of hydrostatic pressure which had to be corrected by a factor of 1.4–2 to give total wind loading – with a wind this would be .Mins of Ev pp. 385–391 (George Stokes) Pole referred to Smeaton's work, where high winds were said to give , with higher values being quoted for winds of or above, with the caveat that these were less certain.Mins of Ev p. 464 (Dr William Pole) Brunlees had made no allowance for wind loading on the Solway viaduct because the spans were short and low – if he had had to, he would probably have designed against with a safety margin of 4–5 (by limiting strength of iron). Both Pole and Law had used a treatment from a book by Rankine. Law agreed with Rankine that the highest wind pressure seen in Britain was as the reason for designing to (i.e. with a safety factor of 4); " in important structures, I think that the greatest possible margin should be taken. It does not do to speculate upon whether it is a fair estimate or not".Mins of Ev p. 321 (Henry Law) Pole had ignored it because no reference was given; he did not believe any engineer paid any attention to it when designing bridges;Mins of Ev p. 471 (Dr William Pole) he thought a reasonable allowance; this was what Robert Stephenson had assumed for the Britannia Bridge. Benjamin Baker said he would design to with a safety margin, but in 15 years of looking he had yet to see wind overthrow a structure that would withstand . He doubted Rankine's pressures because he was not an experimentalist; told that the data were observations by the Regius Professor of Astronomy at Glasgow University he doubted that the Professor had the equipment to take the readings.Mins of Ev pp. 509–10 (Benjamin Baker) =Baker's analysis= Baker argued that the wind pressure on the high girders had been no more than , from the absence of damage to vulnerable features on buildings in Dundee and the signal cabins at the south end of the bridge. The Inquiry felt that these locations were significantly more sheltered, and therefore rejected this argument. Baker's subsequent work on wind pressures at the Forth Rail Bridge site showed meteorologists were overestimating, but his might have over-interpreted the data. Opinions on bridge components Law had numerous criticisms of the bridge design, some echoed by other engineers: *He thought the piers should have been wider (both to counteract toppling and to increase the horizontal component forces the tiebars could withstand) and rectangular (to increase the number of tiebars directly resisting lateral forces); at the very least there should have been lateral bracing between the outermost columns of the piers.Mins of Ev p. 254 (Henry Law) *The lug holes should have been drilled and the tiebars secured by pins filling the holes (rather than bolts). Cochrane testified that he was not surprised that boltholes had been cast conical. He noted that moulders were notorious for this, unless you stood over them. Even so, he would not rely on supervision or inspection, he would have the holes bored or reamed to ensure they were cylindrical because it had an important bearing on the stability of the structure. Pole – called by Bouch's counsel – agreed.Mins of Ev p. 478 (Dr William Pole) *Bouch said if he had known the holes were cast conical he would have had them bored or reamed.Mins of Ev p. 409 (Sir Thomas Bouch) Gilkes said casting lug holes conical would have been done "as a matter of course, and unless attention had been drawn to it, it would not be thought then so important as we think it now".Mins of Ev p. 521 (Edgar Gilkes) *Cast-on lugs tended to make unsound castings (Cochrane said he had seen examples in the bridge ruinsMins of Ev p. 341 (John Cochrane)) and had prevented facing of the outer side of flanges. Cochrane added that their use meant that columns had had to be cast horizontally rather than vertically, thus giving less satisfactory castings;Mins of Ev p. 354 (John Cochrane), confirmed by Edgar Gilkes (Mins of Ev p. 521) and unless lugs were carefully packed during bolting up they could be damaged or strained.Mins of Ev p. 351 (John Cochrane) *For so tall a pier Gilkes would have preferred some other means of attaching the ties to the columns "knowing how treacherous a thing cast iron is, but if an engineer gave me such a thing to make I should make it without question, believing that he had apportioned the strength properly". A letter from Bouch to Gilkes on 22 January 1875 had noted that Gilkes was "inclined to prefer making the joints of the metal columns the same as on the Beelah and Deepdale".Mins of Ev p. 404 (Sir Thomas Bouch) Asked by Rothery why he had departed from the bracing arrangements on the Belah Viaduct, Bouch had referred to changed views on the force of the wind; pressed for other reasons he said Belah-style ties "were so much more expensive; this was a saving of money".Mins of Ev p. 429 (Sir Thomas Bouch) Modelling of bridge failure and conclusions drawn Both Pole and Law had calculated the wind loading needed to overturn the bridge to be over (taking no credit for holding-down bolts fastening the windward columns to the pier masonry)Mins of Ev p. 470 (Dr William Pole) and concluded that a high wind should have overturned the bridge, rather than cause it to break up (Pole calculated the tension in the ties at windloading to be more than the 'usual margin of safety' value of 5 tons per square inch but still only half the failure tension.Mins of Ev p. 468 (Dr William Pole)) Pole calculated the wind loading required to overturn the lightest carriage in the train (the second-class carriage) to be less than that needed to overturn the bridge; whereas Law – taking credit for more passengers in the carriage than Pole and for the high girders partially shielding carriages from the wind – had reached the opposite conclusion.Mins of Ev p. 308 (Henry Law) =Law: causes were windloading, poor design and poor quality control= Law concluded that the bridge as designed if perfect in execution would not have failed in the way seenMins of Ev p. 307 (Henry Law)(Cochrane went further; it 'would be standing now').Mins of Ev p. 346 (John Cochrane) The calculations assumed the bridge to be largely as designed, with all components in their intended position, and the ties reasonably evenly loaded. If the bridge had failed at lower wind loadings, this was evidence that the defects in design and workmanship he had objected to had given uneven loadings, significantly reduced the bridge strength and invalidated the calculation. Hence =Pole: causes were windloading and impact of derailed carriages= Pole held that the calculation was valid; the defects were self-correcting or had little effect, and some other reason for the failure should be sought. It was the cast iron lugs which had failed; cast iron was vulnerable to shock loadings, and the obvious reason for a shock loading on the lugs was one of the carriages being blown over and into a bridge girder. Baker agreed, but held the wind pressure was not sufficient to blow over a carriage; derailment was either wind-assisted by a different mechanism or coincidental.Mins of Ev p. 512 (Benjamin Baker) (Bouch's own view that collision damage to the girder was the sole cause of bridge collapseMins of Ev p. 415 (Sir Thomas Bouch) found little support). ="Did the Train strike the Girders?"= Bouch's counsel called witnesses last; hence his first attempts to suggest derailment and collision were made piecemeal in cross- examination of universally unsympathetic expert witnesses. Law had 'not seen anything to indicate that the carriages left the line' (before the bridge collapse)Mins of Ev p. 266 (Henry Law) nor had CochraneMins of Ev p. 345 (John Cochrane) nor Brunlees.Evidence of James Brunlees p.362 – Mins of Ev The physical evidence put to them for derailment and subsequent impact of one or more carriage with the girders was limited. It was suggested that the last two vehicles (the second-class carriage and a brake van) which appeared more damaged were those derailed, but (said Law) they were of less robust construction and the other carriages were not unscathed.Mins of Ev p. 329 (Henry Laws) Cochrane and Brunlees added that both sides of the carriages were damaged "very much alike".Mins of Ev p. 362 (James Brunlees) Bouch pointed to the rails and their chairs being smashed up in the girder holding the last two carriages, to the axle-box of the second-class carriage having become detached and ending up in the bottom boom of the eastern girder,Mins of Ev p. 441 (James Waddell) to the footboard on the east side of the carriage having been completely carried away, to the girders being broken up, and to marks on the girders showing contact with the carriage roof,Mins of Ev pp. 415–6 (Sir Thomas Bouch) and to a plank with wheel marks on it having been washed up at Newport but unfortunately then washed away.Mins of Ev p. 423 (Sir Thomas Bouch) Bouch's assistant gave evidence of two sets of horizontal scrape marks (very slight scratches in the metal or paint on the girders) matching the heights of the roofs of the last two carriages, but did not know the heights he claimed to be matched.Mins of Ev p. 430 (Charles Meik) At the start of one of these abrasions, a rivet head had lifted and splinters of wood were lodged between a tie bar and a cover plate. Evidence was then given of flange marks on tie bars in the fifth girder (north of the two rearmost carriages), the 'collision with girders' theory being duly modified to everything behind the tender having derailed. However, (it was countered) the girders would have been damaged by their fall regardless of its cause. They had had to be broken up with dynamite before they could be recovered from the bed of the Tay (but only after an unsuccessful attempt to lift the crucial girder in one piece which had broken many girder ties).Mins of Ev pp. 438–9 (John Holdsworth Thomas) The tender coupling (which clearly could not have hit a girder) had also been found in the bottom boom of the eastern girder.Mins of Ev p. 422 (Sir Thomas Bouch) Two marked fifth girder tie bars were produced; one indeed had 3 marks, but two of them were on the underside.Mins of Ev p. 443 (James Waddell) Dugald Drummond, responsible for NBR rolling stock, had examined the wheel flanges and found no 'bruises' – expected if they had smashed up chairs. If the second-class carriage body had hit anything at speed, it would have been 'knocked all to spunks' without affecting the underframe. Had collision with the eastern girder slewed the frame, it would have presented the east side to the oncoming brake van, but it was the west side of the frame that was more damaged. Its eastern footboard had not been carried away; the carriage had never had one (on either side). The graze marks were at above the rail, and above the rail and did not match carriage roof height.Mins of Ev pp. 453–4 (Dugald Drummond) Drummond did not think the carriages had left the rails until after the girders began to fall, nor had he ever known a carriage (light or heavy) to be blown over by the wind.Mins of Ev p. 459 (Dugald Drummond) =Findings= The three members of the court failed to agree a report although there was much common ground:Report of Court of Inquiry pp. 15–16, unless referenced otherwise Contributory factors * neither the foundations nor the girders were at fault * the quality of the wrought iron, whilst not of the best, was not a factor *the cast iron was also fairly good, but presented difficulty in casting * the workmanship and fitting of the piers were inferior in many respects *the cross bracing of the piers and its fastenings were too weak to resist heavy gales. Rothery complained that the cross-bracing was not as substantial or as well-fitted as on the Belah viaduct;Report of Mr Rothery pp. 43–4 Yolland and Barlow stated that the weight/cost of cross-bracing was a disproportionately small fraction of the total weight/cost of ironworkReport of Court of Inquiry p. 13 * there was insufficiently strict supervision of the Wormit foundry (a great apparent reduction of strength in the cast iron was attributable to the fastenings bringing the stress on the edges of the lugs, rather than acting fairly on them) *supervision of the bridge after completion was unsatisfactory; Noble had no experience of ironwork nor any definite instruction to report on the ironwork *nonetheless Noble should have reported the loose ties. Using packing pieces might have fixed the piers in a distorted form. *the limit had not been enforced, and frequently exceeded. Rothery added that, given the importance to the bridge design of the test borings showing shallow bedrock, Bouch should have taken greater pains, and looked at the cores himself.Report of Mr Rothery pp. 41 "True Cause of the Fall of The Bridge" According to Yolland and Barlow "the fall of the bridge was occasioned by the insufficiency of the cross-bracings and fastenings to sustain the force of the gale on the night of December 28th 1879 ... the bridge had been previously strained by other gales".Report of Court of Inquiry pp. 15–16 Rothery agreed, asking "Can there be any doubt that what caused the overthrow of the bridge was the pressure of the wind acting upon a structure badly built and badly maintained?" =Substantive differences between reports= Yolland and Barlow also noted the possibility that failure was by fracture of a leeward column. Rothery felt that previous straining was "partly by previous gales, partly by the great speed at which trains going north were permitted to run through the high girders": if the momentum of a train at hitting girders could cause the fall of the bridge, what must have been the cumulative effect of the repeated braking of trains from at the north end of the bridge?Report of Mr Rothery p. 40 He therefore concluded – with (he claimed) the support of circumstantial evidence – that the bridge might well have failed at the north end first;Report of Mr Rothery p. 30 he explicitly dismissed the claim that the train had hit the girders before the bridge fell. Yolland and Barlow concluded that the bridge had failed at the south end first; and made no explicit finding as to whether the train had hit the girders. They noted instead that apart from Bouch himself, Bouch's witnesses claimed/conceded that the bridge failure was due to a shock loading on lugs heavily stressed by windloading.Report of the Court of Inquiry p. 15 Their report is therefore consistent with either a view that the train had not hit the girder or one that a bridge with cross-bracing giving an adequate safety margin against windloading would have survived a train hitting the girder. Yolland and Barlow noted "there is no requirement issued by the Board of Trade respecting wind pressure, and there does not appear to be any understood rule in the engineering profession regarding wind pressure in railway structures; and we therefore recommend the Board of Trade should take such steps as may be necessary for the establishment of rules for that purpose."Report of the Court of Inquiry p. 16 Rothery dissented, feeling that it was for the engineers themselves to arrive at an 'understood rule', such as the French rule of or the US .Report of Mr Rothery p. 49 Presentational differences between reports Rothery's minority report is more detailed in its analysis, more willing to blame named individuals, and more quotable, but the official report of the court is a relatively short one signed by Yolland and Barlow. Rothery said that his colleagues had declined to join him in allocating blame, on the grounds that this was outside their terms of reference. However, previous Section 7 inquiries had clearly felt themselves free to blame (Thorpe rail accident) or exculpate (Shipton-on-Cherwell train crash) identifiable individuals as they saw fit, and when Bouch's solicitor checked with Yolland and Barlow, they denied that they agreed with Rothery that "For these defects both in the design, the construction, and the maintenance, Sir Thomas Bouch is, in our opinion, mainly to blame.""Responsibility for the Accident": Rothery (1880: 44) Aftermath =Section 7 inquiries= No further judicial enquiries under Section 7 of the Regulation of Railways Act 1871 were held until the Hixon rail crash in 1968 brought into question both the policy of the Railway Inspectorate towards automated level crossings and the management by the Ministry of Transport (the Inspectorate's parent government department) of the movement of abnormal loads. A Section 7 judicial enquiry was felt necessary to give the required degree of independence. The structure and terms of reference were better defined than for the Tay Bridge inquiry. Brian Gibbens, QC, was supported by two expert assessors, and made findings as to blame/responsibility but not as to liability/culpability. =Wind Pressure (Railway Structures) Commission= The Board of Trade set up a 5-man commission (Barlow, Yolland, Sir John Hawkshaw, Sir William Armstrong and Stokes) to consider what wind loading should be assumed when designing railway bridges. Windspeeds were normally measured in 'miles run in hour' (i.e. windspeed averaged over one hour) so it was difficult to apply Smeaton's table which linked wind pressure to current windspeed :P_t = 0.005 (V_t)^2\, where: :P_tis the instantaneous wind pressure (pounds per square foot) :V_tis the instantaneous air velocity in miles per hour By examination of recorded pressures and windspeeds at Bidston Observatory, the commission found that for high winds the highest wind pressure could be represented very fairly, by :P_m = 0.01 (V_h)^2\, where: :P_mis the maximum instantaneous wind pressure experienced (pounds per square foot) :V_his the 'miles run in hour' (one hour average windspeed) in miles per hour However, they recommended that structures should be designed to withstand a wind loading of , with a safety factor of 4 (2 where only gravity was relied upon). They noted that higher wind pressures had been recorded at Bidston Observatory but these would still give loadings well within the recommended safety margins. The wind pressures reported at Bidston were probably anomalously high because of peculiarities of the site (one of the highest points on the Wirral.): a wind pressure of would overturn railway carriages and such events were a rarity. (To give a subsequent, well documented example, in 1903 a stationary train was overturned on the Levens viaduct but this was by a 'terrific gale' measured at Barrow in Furness to have an average velocity of , estimated to be gusting up to .) =Bridges= A new double-track Tay Bridge was built by the NBR, designed by Barlow and built by William Arrol & Co. of Glasgow upstream of, and parallel to, the original bridge. Work started 6 July 1883 and the bridge opened on 13 July 1887. Sir John Fowler and Sir Benjamin Baker designed the Forth Rail Bridge, built (also by Arrols) between 1883 and 1890. Baker and his colleague Allan Stewart received the major credit for design and overseeing building work. The Forth Bridge had a 40 mph speed limit, which was not well observed.p29 J Thomas op cit Bouch had also been engineer for the North British, Arbroath and Montrose Railway, which included an iron viaduct over the South Esk. Examined closely after the Tay bridge collapse, the viaduct as built did not match the design, and many of the piers were noticeably out of the perpendicular. It was suspected that the construction had not been adequately supervised: foundation piles had not been driven deeply or firmly enough. Tests in 1880 over a period of 36 hours using both dead and rolling loads led to the structure becoming seriously distorted and eight of the piers were declared unsafe. Condemning the structure, Colonel Yolland also stated his opinion that "piers constructed of cast-iron columns of the dimensions used in this viaduct should not in future be sanctioned by the Board of Trade." It had to be dismantled and rebuilt by Sir William Arrol to a design by W. R. Galbraith before the line could be opened to traffic in 1881. Bouch's Redheugh Bridge built 1871 was condemned in 1896, the structural engineer doing so saying later that the bridge would have blown over if it had ever seen windloadings of . =Reminders= The current bridge at dusk, with the masonry of one of Bouch's piers silhouetted against the sunlit Tay. thumb The locomotive, NBR no. 224, a 4-4-0 designed by Thomas Wheatley and built at Cowlairs Works in 1871, was salvaged and repaired, remaining in service until 1919, nicknamed "The Diver"; many superstitious drivers were reluctant to take it over the new bridge. The stumps of the original bridge piers are still visible above the surface of the Tay. Memorials have been placed at either end of the bridge in Dundee and Wormit. A column from the bridge is on display at the Dundee Museum of Transport. On 28 December 2019, Dundee Walterfronts Walks hosted a remembrance walk to mark the 140 year anniversary of the Tay Bridge Disaster. Modern reinterpretations Various additional pieces of evidence have been advanced in the last 40 years, leading to "forensic engineering" reinterpretations of what actually happened. Works of literature about the disaster The disaster inspired several songs and poems, most famously William McGonagall's "The Tay Bridge Disaster", widely considered to be of such a low quality as to be comical. The German poet Theodor Fontane, shocked by the news, wrote his poem Die Brück' am Tay.Edward C. Smith III: The Collapse of the Tay Bridge: Theodor Fontane, William McGonagall, and the Poetic Response to the Humanity's First Technologocal Disaster. In: Ray Broadus Browne (ed.), Arthur G. Neal (ed.): Ordinary Reactions to Extraordinary Events. Popular Press (Ohio State University), 2001, , pp. 182–193Translation at Bartelby.com It was published only ten days after the tragedy happened. C. Horne's ballad In Memory of the Tay Bridge Disaster was published as a broadside in May 1880. It describes the moment of the disaster as: : See also * David Kirkaldy * Harry Watts * List of structural failures and collapses * List of bridge disasters * List of wind-related railway accidents Notes and references =Notes= =References= =Bibliography= * Prebble, John, The High Girders: The Story of the Tay Bridge Disaster, 1956 (published by Penguin Books in 1975) . * Thomas, John The Tay Bridge Disaster: New Light on the 1879 Tragedy, David & Charles, 1972, . * Swinfen, David The Fall of the Tay Bridge, Mercat Press, 1998, . * McKean, Charles, Battle for the North: The Tay and Forth Bridges and the 19th-Century Railway Wars: The Building of the Tay and Forth Bridges and the 19th Century Railway Wars Granta 2007. * Lewis, Peter R. Beautiful Railway Bridge of the Silvery Tay: Reinvestigating the Tay Bridge Disaster of 1879, Tempus, 2004, . * Rapley, John Thomas Bouch : the builder of the Tay Bridge, Stroud : Tempus, 2006, * Lewis, Peter R. Disaster on the Dee: Robert Stephenson's Nemesis of 1847, Tempus Publishing (2007) * Rothery, Henry Tay Bridge Disaster: Report Of The Court of Inquiry, and Report Of Mr. Rothery, Upon the Circumstances Attending the Fall of a Portion of the Tay Bridge on the 28th December 1879. London: Her Majesty's Stationery Office, 1880 External links * 91 black-and-white photographs of the wrecked piers of the Tay Bridge showing destroyed piers and girders, wreckage of train and steam engine from National Library of Scotland * Tom Martin's engineering analysis of the bridge disaster * Reappraisal of the Tay Bridge disaster Open University * The Tay Bridge Disaster at Failure Magazine * Dundee local history centre page on the disaster *Tay Victims listing {reference only} *Find a grave memorial of Tay River victims *Firth of Tay Bridge Disaster 1879: Worst Structural Disaster in British History at Suburban Emergency Management Project * Tay Bridge Disaster: Appendix to the Report Of The Court of Inquiry. Includes a large number of drawings of the bridge, and calculations of the result of wind pressure on the structure * Report from the Select Committee on the North British Railway (Tay Bridge) Bill; together with the Proceedings of the Committee and Mins of Ev. All the oral evidence given, reproduced verbatim – a very large file but sometimes a useful corrective to reinterpretation by secondary sources *The Tay Bridge Collection at Archive Services, University of Dundee * Was Disaster Built into the First Tay Bridge? Article relating to the University of Dundee's holdings on the disaster Category:Transport in Dundee Category:Railway accidents and incidents in Scotland Category:Railway accidents in 1879 Category:1879 in Scotland Category:Bridge disasters in the United Kingdom Category:Bridge disasters caused by engineering error Category:Bridge disasters caused by construction error Category:European windstorms Category:Transport disasters in Scotland Category:Thomas Bouch Category:Accidents and incidents involving North British Railway Category:History of Dundee Category:December 1879 events "

❤️ Dumnagual 🦒

"Dumnagual was the name of several kings of Alt Clut, later known as Strathclyde: *Dumnagual I of Alt Clut (c. 6th century) *Dumnagual II of Alt Clut (7th century) *Dumnagual III of Alt Clut (mid-8th century) *Dumnagual IV of Alt Clut (9th century) See also *Dyfnwal (disambiguation) "

❤️ Mike Russell (billiards player) 🦒

"Mike Russell (born 3 June 1969 in Middlesbrough, England), is a twelve-time WPBSA World Champion in the game of English billiards. He also has six IBSF World Billiards Championship titles standing to his name. He has been described as an "archrival" of India's prodigy, Geet Sethi, an eight-time World Champion, and each of them had defeated the other for the title, with Russell victorious in 1996, and Sethi the winner in 1998, as of their next encounter at the 2007 event. Both scored two apiece, but Russell knocked Sethi out in the semi-finals, 1835–1231, (65.5 vs. 45.6 average). Russell went on to win the title for the ninth time and a £6,000 prize, solidly beating Chris Shutt, 2166–1710 (52.8 vs. 42.8 avg.), with four double and four triple centuries to Shutt's four and none, respectively. At the IBSF World Billiards Championships 2010, Russell not only claimed the 150up- and time-format title, recorded a break of 1137 points in the time-format final. Even though the amateur rules applied in this tournament do not include the "Baulk line rule" used in professional events, he is only the fourth player ever to score a break of over 1000 in an official match under modern rules. Personal life He has a son who is named Luke Russell who was born on 21 July 1996. He studied in England then shifted to India to the British International School and has now moved back to England. He has an elder son named Karl who is 21 years old and is a former junior MMA champion. He is married to Ayesh Sumuduni Russell since 2010 and they reside in Qatar. Mike Russell moved to Qatar where he acts as trainer for the QBSF (Qatar Billiards and Snooker Federation) since 2007. References External links * Mike Russell bio at BillardsForum * Time to hail Mike Russell, the king of billiards Article by John Inverdale in Daily Telegraph, 1 August 2007 Category:1969 births Category:English players of English billiards Category:Living people Category:British emigrants to Qatar Category:World champions in English billiards "