"MYERS' FOLLY."

Auckland Star, Volume LXVII, Issue 169, 18 July 1936, Page 11

"MYERS' FOLLY."

GRAFTON BRIDGE. A CONTROVERSY OF 1906. CRITICS CONFOUNDED. When, thirty years ago, the ratepayers of Auckland sanctioned a City Council loan of £30,000 for the building of a high-level bridge, they disregarded i | a host of self-constituted advisers, wlio j | maintained that a foot-bridge half-way i down the gully would suffice Auckland's 1 j needs for the next forty years. For petty spite, the opponents of the scheme called it "Myers' folly"—the late Sir Arthur Myers was Mayor at the time. Although the poll was carried, the "anti-bridge" party later scored a series of minor victories that will, in a few years time, cost Auckland dearly. I Twelve months of bitter controversy j followed the carrying of the loan poll j in April, 190 C, and then, having at last j decided to go ahead .with the project, the i council called for tenders in such a hurry that insufficient time was given for the preparation of full plans and specifications, which each tenderer was required to furnish. Cost Limited. Under these circumstances, the Ferro-1 Concrete Company of Australasia, I decided not to tender, but Mr. R. F. ■Moore, then chief engineer ol the comI pany, disobeyed his directors' orders and sent in a-sketch of a ferro-concrete bridge, which he estimated would cost £35,000. The only other design received was for a steel girder bridge, which, though £3000 cheaper than the concrete one, would have cost a considerable sum annually for upkeep. The concrete bridge was therefore the obvious choice. I In submitting his plan, Mr. Moore ! prayed the council to provide sufficient j money for the building of a. bridge with i-a roadway 39 feet wide, instead of 24 I feet, but on this issue the "anti-bridge" J party won a, disastrous victory. Expen-

diture on the' project was limited to ] £40,000, and as £2500 had to be spent i on the construction of the approaches j and £5000 on the purchase of land for 1 the site of the bridge, even £35,000 was j more than the council could devote to • the building of the bridge itself. Instead, - therefore, of building the bigger bridge ; that he knew Auckland would need within a few years, Mr. Moore had to eliminate sundry items from his schedule to bring the cost of the smaller one down to £32,000 before the City Council would accept his tender. Practicability Doubted. j Even then, many doubted whether | Mr. Moore or any other mail, could build j a 320 ft arch. 147 ft high, of ferro-con-1 crete. Nothing approaching such a size | had ever before been attempted anywhere in the world, and such a daring | ■experiment frightened • even some of j those who realised that a., high-level | bridge of some sort wis necessary. In accepting the tender, the City Council stipulated that no payments were to be made to the FerrO-Coricrete Company j until the arch was completed and tested, i To Mr. Moore this was . a challenge that I he could not but accept; to the public, it I was a- confession by the council . of a j lack of confidence in the design, and j j riticism was intensified a hundred-fold, j I Everyone became an- engineer inj I those days, and joined either the school i that maintained that the arch could! | never be built or the school that de-1 clared that the whole bridge would blow down in the first gale. Greatest in the World. Still the concrete poured into its moulds, until the approaches were completed as far as the huge pylons on each | side of the gully. "Now, watch," said j the doubters. "Yes, now watch," said j Mr. Moore, confident as ever. From, the j | depths of the gully rose a lattice-work j of timber, right up to the road level. I Through this could be seen, the wooden '.moulds of the. arch, like a rainbow seen I through a trellis. Frail as it was to all appearances, it mocked the critics by withstanding the superimposed load that eventually came upon it with a yielding, in the extreme case, «f only one inch and an eighth. When the timbering was removed, there stood the bridge that could not be built—"Myers' Folly"—the greatest ferro-concrete span in the world, with 3800 tons of steel and concrete fashioned into. graceful form. Still there were

many doubters. At one council meeting shortly after the arch was completed a councillor caused a momentary panic by stating that the bridge was already in danger of collapsing, for he had seen with his own eyes a crack right across the centre. The meeting was reassured, however, when the engineer explained that this was a joint to allow the bridge to expand and contract with changes of temperature. - The final test was the passage of two •road rollers, each weighing approximately 30 tons, over the bridge, and, this having been successfully passed, the bridge was officially opened on April 28, 1910, two years and seven months after it had been commenced. j "Article of Faith." I From time to time the old canards j were revived, only to be promptly squashed by the city engineer, Mr. J. Tyler. On January 19, 1932, in reply to a letter in the Press complaining of the vibration of the bridge, Mr. Tyler I paid a very fine tribute to the builders. I "Up to the present time," he stated, "not | one shilling has been spent on mainI tenance or repairs to the structural por- | tion of the bridge." Tests carried out j with the cement during the construction ! of the bridge, he stated, showed that it I would get stronger, not weaker, with I age. From being a subject of heated j debate and grave doubts, the stability of Grafton Bridge had become an article of faith not only with the lay public, but also with architects and engineers. It was discovered early this year that there was a weakness in the two approach spans at the Grafton Road end of the bridge, but, with justice, it has been pointed out that no engineer, even one so optimistic of Auckland's futura : growth as Mr. Moore, could have fore- : seen in 1900 the terrific weight of traffic . that the bridge would be called on to i bear, or could have allowed in advance i for the then unthought-of vibrations and 1 stresses that would be put upon it by ' the fast passage of heavy motor vehicles. [ A comparison, however, of the cost at t the bridge, £32.000, with the cost of tire ' repairs now planned, £25,000, shows the cost of labour and materials has increased, for the estimate of £25,000 1 covers only the replacement of the - web girders at each end of the brii g , with solid reinforced ones and e | tion of additional piers to reduce w . length of the spans by