SHB Pylon 1
Skipper and First Mate Millard (Big Bear and Pepe)
Sat 27 Feb 2016 23:47
Sydney Harbour Bridge Pylon Visit - Middle Level
Part of our BridgeClimb ticket gave us a pass to visit the Pylon Lookout, just two hundred steps up to the top..... Seventy steps up we were surprised to find a pay desk, small room full of information boards – a stained glass window up to our left and the room beyond .......... a cinema...... begged us to spend a few minutes catching our breath, sadly, the same film as we had seen before but it gave us back a normal heart rate before we read all the boards.
“There can be little doubt that in many ways the story of bridge building is the story of civilisation. By it, we can readily measure an important part of a people’s progress.” Franklin D. Roosevelt, speaking in October 1931.
It took a long time for the dream of a bridge across Sydney Harbour to become a reality. Though many people believed that a bridge was both desirable and necessary, there were many delays and several heated battles before it was finally built. The ongoing disputes were not restricted to whether the bridge was justified. Throughout the nineteenth and early twentieth centuries, various ideas and schemes about what kind of harbour crossing would be the most suitable were proposed and keenly debated. “The expense of constructing a bridge from Sydney to the North Shore would be but trifling compared with the benefits to be derived from such a construction.” 1881 Petition to the Legislative Assembly requesting a bridge linking Sydney to the North Shore.
Construction of a bridge linking north and south Sydney seemed fated to be permanently on hold. One factor that made the delay more viable was the existence, from the early 1840’s onwards, of an efficient ferry service across the harbour. With the opening of the railway between Milsons Point and Hornsby in the 1890’s, and a steady rise in settlement on the north shore, the ferry service continued to thrive and expand.
Reasonable road links had also been established between the city centre and the northern suburbs in the 1880’s. Most food and goods went via a circuitous route over the Gladesville Bridge. Given these existing transport options, many politicians argued that the cost of a bridge was just too high.
“O, who will stand at my right hand, and build the bridge with me?” New South Wales politician Sir Henry Parkes’ election cry in the 1880’s.
Bridge or Tunnel: Debate about a harbour crossing extended beyond questions of cost. The issue of what form of harbour crossing would be most desirable also sparked controversy over the years. Various schemes, designs, locations and concepts were mooted. From 1885, for example, arguments raged over whether a bridge or tunnel would be best. A Royal Commission considered the matter in 1890 and concluded that neither was necessary. But between 1896 and 1899 four separate private members bills’ called for either a bridge or a tunnel. All were rejected or lapsed following a change in government.
In 1900 and again in 1903, tenders were called for a Sydney Harbour Bridge. Norman Selfe’s design for a cantilever bridge from Dawes Point to MacMahons Point was accepted in 1903 but later dropped. By the early twentieth century, after decades of debate, schemes and interminable delays, the bridge remained as remote as ever.
Getting serious: By the early 1900’s, it was increasingly obvious that some form of harbour crossing was needed. Time-consuming changeovers from transport links at either side of the harbour were causing complaints and north shore residential areas were rapidly expanding. In 1908, yet another Royal Commission recommended a bridge for vehicles and pedestrians and a subway for rail traffic. In 1911, John Job Crew Bradfield, entered the fray.
A photograph by me of a photograph by Michael J Bradfield of a mid-1920’s portrait painted by Gerald Norton of Dr. Bradfield.
The ‘Father’ of the Bridge: Dr. John Job Crew Bradfield [1867-1943], is the acknowledged ‘father’ of the Sydney Harbour Bridge, having nurtured and guided it from concept to completion. Born at Sandgate, Queensland in 1867, Bradfield earned a Bachelor of Engineering from the University of Sydney in 1889, a Masters in Engineering in 1896 and a Doctor of Science in Engineering in 1924. His working life began as a draughtsman with the Queensland Government Railway. He then moved to the New South Wales Department of Public Works, where he rapidly rose to the position of Principal Designing Engineer. In 1912 he was appointed Chief Engineer of the Sydney Harbour Bridge and Metropolitan Railway Construction.
In 1914, Bradfield travelled overseas to investigate different bridge options, and was particularly impressed by New York’s Hell Gate Bridge. In 1922, he again went abroad, this time to investigate prospective tenderers. In the same year legislation at long last authorised the construction of either a cantilever or an arch bridge, to be integrated with road and rail systems on both sides of Sydney Harbour. The dream was to be realised.
A man of talent and tireless energy, Bradfield played a leading role in determining what type of bridge was most suitable. He then capably and efficiently supervised its design and construction. He and his staff checked and approved all of the detailed design work, computations, drawings and calculations undertaken by Dorman Long and Co. staff in England.
Although the Sydney Harbour Bridge was Bradfield’s most celebrated monument, he was involved in numerous other projects in the course of his long and illustrious career. There included the Story Bridge over the Brisbane River and the Cataract and Burrinjuck Dams in New South Wales.
“...you could never mistake Doctor Bradfield walking down the shop, you’d –know him. He was a good bloke and he – took pride, a great deal of pride in the work. He is recorded as saying that he was proud of the workmanship, proud of the workers in the shop, that they did a mighty job....”. Charles Brown, a ‘marker off’ in one of the construction workshops, recalling J.J.C. Bradfield.
“I realised he was a dreamer. But behind it all was his conviction he was planning the greatest City in the Southern Hemisphere....” Jack Long, Premier of New South Wales.
Strong and Handsome – The Winning Design: When tenders closed on the 1st of January 1924, six companies from around the world submitted twenty different proposals for a Sydney Harbour Bridge. The winner was Dorman Long and Co. Ltd. of Middlesbrough, England. The chosen design was a two-hinged steel arch with five approach spans at each end and four pylons. At eleven hundred and forty nine metres long and with a forty nine metre wide deck, it was estimated to cost the government four million, two hundred and seventeen thousand, seven hundred and twenty two pounds. There were practical reasons for choosing this type of bridge. Most importantly, a steel arch provided strength, stability and rigidity needed to accommodate four railway lines, six roadways and two footways. The selected bridge’s total capacity was an estimated one hundred and twenty trains, six thousand cars and forty thousand pedestrians an hour.
A steel suspended bridge, though attractive, would not have offered the necessary load-bearing capacity. A cantilever bridge, though economically and technically viable, was less visually imposing than a steel arch. The winning design reflected the influence of New York’s strong and handsome Hell Gate Bridge.
The construction of the Sydney Harbour Bridge involved the use of fifty two thousand, eight hundred tons of steel. From the 1870’s, when the world price of steel dropped by seventy five per cent, a new era of bridge building opened up. Steel was so versatile, it enabled established building methods to reach new peaks of development. Steel not only provided its own possibilities of new forms, it also enabled concrete, the other new material of the late nineteenth century, to evolve as an effective medium.
Designing the greatest steel bridge in the world required skill and considerable ingenuity. Two major engineering problems needed to be resolved at the outset. The first involved changes in temperature. Steel expands as it warms up and contracts as it cools. To allow for the fact that the top of the arch actually rises and falls about one hundred and eighty millimetres due to temperature changes, hinges [two at each end] were incorporated into the design. These hinges or bearings support the full weight of the bridge, spreading their load through concrete skewbacks into a foundation of solid sandstone. They also allow the bridge to move when the steel expands or contracts.
The other problem was how to keep the sides of the arch from crashing down while being built. One option was to place temporary supports in the harbour but that would have been expensive and a potential shipping hazard. The solution adopted was to hold each side back with steel cables firmly anchored in thirty six metre long horse-shoe shaped tunnels dug into the sandstone bedrock on both sides of the harbour. Each of the one hundred and twenty eight cables weighed eight and a half tonnes and was made up of two hundred and seventeen individual wires.
The joining concept was simple. When the two spans were complete, the cables would be gradually loosened from each end allowing the half arches to meet in the middle.
The successful tenderers, Dorman Long and Co. Ltd. signed a contract with the government on the 24th of March 1924. Faced with an undertaking of monumental proportions, their staff lost no time in getting started. Lawrence Ennis, O.B.E. [1872-1938], Director from 1924-1932 oversaw from the Dorman Long site office in the Artillery Barracks at Dawes Point, the excavation and levelling of large areas at Milsons Point, the construction and equipping of light and heavy fabrication workshops on that land, where fabrication workshops would be constructed and equipped; buying ships and building wharves where ships could unload bulk steel, and the creation of a new town for the quarry workers at Monuya. These were only some of the preliminary steps required. He then embarked on the massive task of co-coordinating the complex construction process.
Throughout the construction process, Ennis relied on the work of designers, whose plans were translated into reality. The overall look of the bridge owed much to Bradfield, but all of the detailed design was undertaken by the contractors’ consulting engineer Ralph Freeman. His associate G.C. Imbault was responsible for erection schemes for each of the designs.
The successful completion of the bridge owed much to Freeman and Imbault’s talents and to their meticulous attention to detail.
Ennis was generous in his praise of the capabilities of Australian workmen. This helped foster a positive workplace culture among the bridge workers. He once said, “Every day those men went to the bridge, they went.....not knowing whether they would come down alive or not....”.
Construction of the Sydney Harbour Bridge began in 1924 during an economic boom. By 1928, however, the Great Depression had descended. The outlook grew steadily darker:at its worst the New South Wales unemployment rate reached 32.5%. The gloom only began to lift in 1933.
The bridge was often called the ‘Iron Lung’ because it kept the economy breathing and so many people in work during the eight years of its construction. Between 1924 and 1932, an average of fourteen hundred people were directly employed on the bridge project at any one time. Many more jobs, however, were provided by various sub-contracting companies, which supplied everything from rivets to sand.
A stonemason - “Carrying my first pay packet, I walked to the city to Gowings and bought a suit for three pounds, ten shillings, a pair of shoes for eight shillings and eleven pence and a hat for ten bob. I came out fully dressed.”
The Sydney Harbour Bridge contains the heaviest steelwork of its kind ever constructed. The engineers involved on the project needed to use innovative techniques and adapt them to meet the special challenges presented in building the greatest steel arch in the world.
Above is a hinge or bearing. The Sydney Harbour Bridge has four such massive hinges; two at each end. These both support the full weight of the bridge, and allow it to move when the steel expands or contracts due to changes in temperature
Each bearing or hinge pin is a cast steel rod four point two metres long and three hundred and sixty eight millimetres in diameter. The pin is cradled in an enormous cast steel ‘saddle’ that transfers the load to the concrete skewbacks. Another saddle, upside down and fixed to the bottom of the bridge, sits on top of the pin.
Made in England at Darlington Forge Co. Ltd, the bearings each take a load of twenty thousand tonnes and weigh three hundred tonnes.
From Dogmen to Tin Hares: Building the bridge required many different kinds of skills and offered some uniquely challenging occupations. For example, ‘dogmen’ who helped to co-ordinate the hoisting of loads often rode the steel up from the barges, communicating all the while by telephone with the crane-operators.
Riveting, in the workshops and on the bridge, was done by boilermakers, each of whom worked with a special team. A ‘cooker’ heated up the rivets in a small portable oven, then threw them to a ‘mate’ or ‘holder up’ who caught them in a bucket and held the rivet in place while the riveter worked on the other end.
Most of the steelwork was put together by about one hundred and fifty riggers. However, there were only twelve officially appointed ‘tin hares’ [six per side], who jockeyed each steel piece into position, fastening the nuts and bolts and adjusting the angles before riveting took place.
“I saw rivet cookers throwing the almost white-hot rivets. They flew like sparklers through the air, shedding burning scale everywhere, before landing in the catcher’s bucket.”
Building the Sydney Harbour Bridge was a perilous process. Basic protective gear of the kind now taken for granted did not exist and safety precautions were few and far between. Men working at dizzying heights enjoyed ‘no luxuries’ such as safety rails or nets. Neither hard-hats nor ear-muffs were worn. Many iron workers and boilermakers later suffered serious hearing problems from prolonged exposure to workplace noise.
Those who laboured in the huge dark box chords and girders were frequently showered with red hot scales of metal from the rivets being hammered into place above them. They could also cut themselves on metal shavings. Under these extreme conditions, overalls were reduced to shreds in a matter of weeks.
“You had to hang on by your eyelashes.” Tom Tomrap, one of the select steel erectors or ‘tin hares’ who, with the crane drivers, erected the bridge.
“ A bloke called Kelly fell a hundred and fifty feet off the deck of the bridge into the water and survived with two broken ribs. When they got him out his boots were split right open and were up around his thighs. They gave him a gold watch.” Our guide, Alex, told us this story on our BridgeClimb. Kelly had just two weeks off and was back at work.....
“It was deafening and practically no lighting at all and .... I used to stand on the heads of the rivets to try and get a balance to hold the rivet in firm position..... The sparks used to fly and I’d often have burns on my neck and arms......” George Evendon recalls working as a riveter inside the chords of the arch.
“There were six million rivets used in the bridge, in its erection and joining of the parts, and in order to locate the holes which rivets go into, it was necessary to mark those positions – you make an indent into the steelwork with a punch – that is what is called ‘marking off’”. Charles Brown, who worked as a ‘marker off’.
“....the men working for me marked the holes in various angles and plates, it was my responsibility to check them. Check every hole that they marked before the angles and plates were sent to the drillers and I can virtually cross the bridge today and suggest that I’ve had my ruler on every one of the holes that those rivets fill up.” Bert Payne, Charge-hand marker-off..
Building Sydney Harbour Bridge was a massive, multi-faceted and complex project. It provided employment for a vast range of occupational groups, from surveyors, engineers and draughtsmen to riveters, stonemasons, crane drivers, machinists, labourers and many others.
The great majority of bridge workers were Australian born or immigrants but an important group of skilled workers from other nationalities were recruited, including Scottish and Italian stonemasons, Irish and English boilermakers and machinists, and British and European riggers.
Through the work was often demanding and dangerous, the various bridge workers felt a special camaraderie and shared sense of pride. Everyone was aware of the fact that the project would stand or fall on the basis of the quality and precision of their workmanship.
“I’ve never worked with a more honest, hard-working crowd who were dedicated to their job. Their relationships to each other were to my mind, excellent and I think they knew that they were battling against the elements and against all the engineering problems to get this thing across and I think it gave them more or less a common cause.” Assistant Public Works Photographer.
Many of the tools were very simple but in talented hands. Today bridge workers are well protected and Health and Safety is uppermost. It costs about three million dollars a year to keep the bridge good condition.
The Day the Arches Joined: By the 7th of August 1930, the two half arches were finished. A gap of only about one metre separated the two sides. Director of Construction Lawrence Ennis laid a short plank across the gap and became the first person to ‘cross’ the Sydney Harbour Bridge. Having taken this historic step, he gave the order to start slackening the tie-backs, so that the two half arches would line up and join together perfectly.
This crucial process took eight nerve-racking days. On the 13th of August, Sydney was buffeted by a violent windstorm. But although the arches swayed perilously, they withstood the test. By the 19th of August the two sides finally touched. They soon separated however, as the day cooled and the bridge steel contracted. After more work on the cables, they touched again at ten at night. This time they remained joined and the arch was complete. A signal was given and celebrations commenced. The next morning the Australian flag and the Union Jack waved triumphantly from the jibs of the creeper cranes. Vessels sounded their horns and ferry passengers cheered as they passed what had, overnight, become a bridge.
The Centre Pin: Suspended above the main staircase is an original, half scale, plywood model of the massive centre pin that was used to fasten the two half arches together. The pilot pin is about twenty five centimetres square in section. When the cables on both sides of the bridge were gradually released, allowing the two half arches to come together, the pins on the south slotted perfectly into opposite recesses on the north side.
Rock from Moruya: The pylons and the approach span piers of the Sydney Harbour Bridge are faced with granite. At Moruya, three hundred and sixty kilometres south of Sydney, Dorman Long and Co. built a new town to house two hundred and fifty quarry workers and their families.
‘Granite Town’, as it came to be known, soon included seventy two pre-fabricated wooden houses, a school, hotel, post office and recreation hall. Many of its inhabitants were skilled masons newly recruited from Scotland and Italy.
These were eighteen thousand cubic metres of rock facings needed for the bridge. The stones were cut to size and completely finished at the Granite Town quarry according to detailed sketch plans. They were then numbered for fitting into place at the bridge site. When the quarry closed, the town was moved to Orient Point, and is still lived in by part of the local Aboriginal community.
Functional and beautiful. The value Dr Bradfield attached to the latter is revealed by his stance on the pylons. He insisted these be added to the original design, largely because they would make the bridge more attractive. Though the pylons’ immense weight does help firm the foundations, their function is primarily decorative. Moreover, Bradfield insisted that to be suitably imposing they needed to be faced with granite. Despite the fact that this involved considerably more expense, about two hundred and forty thousand pounds, he justified this on the grounds that only a “strong imperishable” natural product like granite would “humanise the landscape in simplicity, strength and sincerity.” Design of the pylons was undertaken by the consulting architects, Sir John Barnet and Partners of London. Thomas Tait, the architect who carried out the work, produced a stripped classical treatment with strong Art Deco components.
“The bridge could have been built without them, a massive iron structure of usefulness only.” Reverend Frank Cash.
This is one of the original art deco style lanterns used to light the Sydney Harbour Bridge. It was probably fixed to the steelwork above the railway, but directed onto the road. All of the original bridge lighting equipment was designed by the New South Wales Public Works Department and contracted to Lawrence and Hanson Electrical Co. Ltd. of Kent Street. However, the fittings were manufactured on subcontract by a group of unemployed engineering graduates in a small leased factory in the Sydney suburb of Alexandria.
The original bridge lighting was installed by the NSW Government Railways, under Chief Electrical Engineer W.H. Myers. It was powered from the Ultimo and White Bay power stations, through substations at Argyle Street and in the north and south west pylons.
Building the Sydney Harbour Bridge captured the Australian public’s imagination. Steel and concrete construction had never before been witnessed on so grand a scale. Photography was a vital means of preserving this awe-inspiring engineering feat for posterity. Though cameras were heavy and often unwieldy, and processing glass plate negatives was time-consuming, there was widespread enthusiasm for taking photographs in the late 1920’s and early 1930’s.
During the eight years of its construction, the Bridge attracted a vast range of amateur buffs and professionals. However, the work of the three talented photographers featured here – Robert Bowden, Henri Mallard and the Reverend Frank Cash stand out for their accuracy and artistry.
Henri Mallard: Where Bowden documented the engineering details, Mallard, a founding member of the prestigious Sydney Camera Circle, captured the workers and their culture. His ground-breaking industrial photography resulted from shots taken among the workers themselves, and from any height.
Robert Bowden: As head of the Public Works Department team of photographers, Bowden photographed all stages of demolition, excavation, fabrication and construction. This enabled the engineers to keep track of the workers’ care and accuracy. He and his assistants lugged their cameras along the arch and bravery perched on steel beams to get required shots.
Reverend Frank Cash: Every morning for a year, the Rector of Christ Church, Lavender Bay [a former engineer] leapt from his bed to take a photograph of the bridge reflected in the harbour. Parables of the Sydney Harbour Bridge, the volume that resulted, was original and unique: part photographic portrait and part engineering journal, liberally laced with biblical texts.
The bridge over the years of construction.
Stained glass windows are a traditional method of decorating architectural spaces and permanently recording events and characters from the past. The stained glass windows in this chamber were created and installed in 2003. The appearance of the windows changes all day long, light is reflected, illuminated and projected as the outside lighting level rises and falls.
There is a surveyor measuring levels, a concrete worker mixing cement, a painter high up in the steelwork of the bridge, a rigger, a stone mason working n the granite faced pylons, a riveter and the silhouette of a dog-man high above the other workers. The glass artist was Robin Seville and she describes her work “I was excited by the opportunity of producing windows for such a grand space but also aware of the unique design and structural challenges which existed. After many discussions with the designers and much research I was sure that the approach had to be bold, colourful and contemporary, but with an underlying Art Deco theme giving a sense of both time and place. The characters portrayed are representative of many of the trades involved in the making of the bridge, the poses are purposeful, even heroic. The background of blue and grey represents their working environment – steel, sky and water.”
ALL IN ALL SPLENDID VISIT
STEEP STEPS AND TONS OF INFORMATION