After the War

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Back to Book Structure | Previous Chapter: The Army - 7th Mechanical Equipment Coy | Next Chapter: Chief Engineer of Structures


On rejoining the P.W.A.D. (Public Works Department Architectural Division) after war service, before the volume of design built up from it's dearth during war time, I spent time examining metropolitan government and private buildings and other constructions to assess their general condition. This was because damage to the external brick cladding of the multi-storey Royal Perth Hospital, built just before the war, had occurred during the five year war period and highlighted the need. The government tended to build long low buildings on large plots of land whereas private industry tended to build high narrow buildings on small plots of land. My experience allowed me to contradict many private consulting Engineers several times, when they reported on various buildings and other distressed structures, sometimes in court cases. One memorable occasion dealt with a massive crack in a 3 or 4 storey brick Uni building on the side of Mounts Bay Road opposite the river at the junction of Hackell Drive. The consultant's report said the cracking was due to subsidence caused by the land sliding into the adjacent Swan River. I proved that the cracking was caused by the rusting of 'hoop iron' straps that used to, in days gone by, be laid in the mortar joint to provide tension strength to the brickwork. Rust can exert a force of 80 tons per square inch.


Another occasion was the Coroner's inquest into the death of a rigger, assisted by his son in the dismantling of the triple steel wire guyed wireless tower on top of Newspaper House in St Georges Terrace. The rigger was seated on the bottom of a long rope which had been threaded through a pulley at the top of the tower, when pulling himself to the tower top, between two of the wire guys, the top bent outwards from the tower by swivelling at the mid level guys. This swung him and tower top sideways a considerable distance, and still swivelling, also swung downwards and inwards hitting the side of the building with considerable force which killed the rigger. The consultants report to the Coroner was that the rusting of the tower at mid guy level had caused the tower to fold and rotate at that point. My report to the Coroner after the examination of debris was completely different to the consultant's. Although the twine covering was long enough to indicate the necessary 8 tucks to each of several guy loop splices, there was only 2 tucks to each loop. Also all guy ropes were in several sections and joined by massive ceramic insulators, some of which had split down the middle which would allow, under excessive loads, for the two loops to come together with a considerable jolt pulling out the two tucks of the splices; so opening the loop and destroying the supporting action of the guy rope. The action of the rigger pulling himself up and kick himself away from the tower at the start of each pull put an outward force on the tower top, which increased the higher he went. This outward force at the top put a larger load on the rear guy opposite the rigger. This extra load caused the split ceramic guy rope connecters to open up and allow the two adjacent loops to come together, the impact of which would cause the 2 tuck loop splices to slip out, this in turn caused the back guy opposite rigger to fail allowing the top of tower to swing out under the influence of the outward force caused by rigger. The combination of this outward load at the top, the distance between top and mid tower guys and the considerable extra load to the single tower leg that the rigger was kicking against caused the leg to buckle allowing the tower to bend and rotate at this point. So my contention was that responsibility for the death was not due to rust, but lay squarely with the splicer of the wire rope guys.


refer to sketches in draft


My contradictions of consultant's reports over the years did nothing to improve their opinion of me. Because of all the above, part of my training of new Engineering staff included sending them to examine and explain the causes of distress in various government and privately owned buildings and other constructions. Mostly they were wrong in their assessments!


On one occasion I checked the structure of a large drive-in theatre screen. All of the screen's structural members were of adequate size so I assumed that all the 'site bolted joints' used to assemble the structure would also be quite adequate even though the details of these had not been submitted. A few months later, during a severe winter storm this assumption was proved to be wrong. The screen was completely demolished by the wind and the ground peppered with broken nuts and bolts. So another lesson learned, 'don't take anything for granted' or on face value. Also, any statement issued by a "loud authoritative voice" should be instantly disbelieved.


Shortly after the war when I had few staff, the School of Engineering was relocated from Shenton House to the West alongside Fairway. I designed and supervised the construction of the new buildings and later the three annexes for the laboratories and workshops for the three divisions of Engineers, Structural and Mechanical and Electrical.


I also worked on a site of a mental institute in Greylands. The original adjoining yards, attached to the cells where the patients lived, were surrounded with high brick walls. Brickwork expands about ½" per one hundred foot length, this movement over the years caused the corners of these yards to shatter. At the time action was taken to demolish these walls and replace them with high wire mesh fences to eliminate the confining 'institutional' effect on the patients. The brick from the demolished walls were cleaned of all mortar and stored for future use such as free standing curved walls or as outdoor stages that were then being introduced in certain schools.


Later on the Astronomy Society of W.A. built a special observatory in the country, in Bickley, well away from city and suburban lights. The massive telescope was based on a high central tower separated from the surrounding enclosed building. This solid tower had to be completely stable and unmovable providing continues accuracy of throughout lengthy observations, so I had the tower built with the above mentioned asylum bricks on a very thin mortar bed to minimise its shrinkage. The entry to the building was via a high concrete staircase between the ground and the observation floors. During trials it was discovered that people walking up or down them caused the stairs to vibrate, this movement was transferred to the observation floor. I then had to devise and attach to the undersides of the stairs a system of heavy weights that absorbed the stair vibrations and keep the observation floor completely still.


When my construction workload did increase it mostly concerned steel structures. Pre WWII steel structural sections were all rolled so 'open' not 'closed' like tubes (see diagram), all were in very short supply after WWII but tubes such as water pipes etc. were abundant.


INSERT DIAGRAM OF PRE WWII STEEL STRUCTURAL SECTIONS


Because of this I decided to use tubes in lieu of the usual angle irons. I therefore obtained the dimensions of all pipes from ½" to 6" internal diameters and calculated their load carrying capacity as tension and compression members and produced a relevant design table. Through this process it became obvious that tubes were far superior to the habitually used angle irons due to:


a) The material is concentric to longitudinal axis and is closed section creating admirable torsion (twisting) ability, both these conditions are lacking in angle irons.

b) Because of this superiority over angle irons, they can be made from less material and still resist an equivalent load. This meant that although tubes cost more to produce, their costs of use in a construction would be approximately the same.


A few years after the war, when I was designing ALL roof trusses using pipes in lieu of the pre-war angle irons, I was asked to design a new workshop for the P.W.D. machinery Storage and Repair Depot in east Perth. By this time the P.W.D. had acquired a multitude of heavy tracked earth moving machines that had replaced the pre-war horse drawn drag line buckets etc. This workshop was to be used to de-track the vehicles, roll the track up and hoist them on a truck and take them to already existing factory for repairs. The new factory included a one ton monorail hoist attached to the bottom chords of the trusses, when it was finished, the workmen flatly refused to work in as they were used to working in the old factory with large over-sized heavy timber trusses over head. The silhouettes of the pipe trusses were much smaller so the workers said they were made of 'fencing wire' and any extra loading would collapse the building. I eventually persuaded a small group of them to drive in and coil up the track of one of the big machines then wait outside, but still within sight of the interior. I used the hoist to move the track up and down, to and fro. I would force the load to stop and start rapidly making it bounce and sway. This of course shook the building slightly but had no other effect on it. After the demo., the workers, some still with doubtful looks, agreed to work inside. So I became a potential strike breaker.


Quite a few years later, through the aegis of my wife I designed the structure for a factory to produce windmills. Later I was told that the structure was fabricated and erected for a price much less than the cost of the raw pipe materials from tube wrights for one of their standard designs. Result – a very satisfied client!


All the above was years ahead of the 'Steel Industry' producing their own design table for tubes for the rest of Australia and decades before the UK followed suit, as I discovered 20 years later whilst in the UK on a U.W.A. Gladden Travelling Fellowship, obtaining further qualifications at Imperial College, London University.


Eventually the Australian tube makers realising the low capacity of tubes for resisting bending due to small amount of material at top and bottom of cross section vertical axes started to manufacture tubes of square and rectangular cross section i.e. SHS and RHS.


During my 37 yrs of practice I came across a saying - "those that can do, and those that can't, teach". I did the first full time and as an adjunct, the second.


After WWII there still was no established School of Architecture. Budding Architects had to be indentured (as Cadets) to a practicing Architect. The Western Australia's P.W.D.A.D. arranged for cadets to attend training lectures given by other Architects, either in their offices or at a local Technical College. Prior to and for a period post WWII the vast majority of Professional Engineers were employed by the Commonwealth or State Government, which meant that the then Architects had to learn a modicum of Structural Design. After WWII a structural lecturer at U.W.A. School of Engineering was employed to give evening lectures at the Perth Technical College. The exam at the course's end was set and marked by another private practicing Engineer. His pass rate was about 75%. Some time after the war, he resigned and I was asked to take over, which I did. My pass rate for the set and marked exams was always 100%.


One of these students eventually became my wife. It was because of her that I learned that Architects' efforts at structural design were very conservative (as was that of the Engineers in private practice at the time) because their design fee was a percentage of the structure's cost. On one occasion, while my wife's mentor Architect was away, a client asked his son to reproduce plans of a factory originally designed by his father. I had tutored the son in structural design so at my wife's suggestion I checked the plans he made. The end result was that where the original factory cost £20,000, years later, the design in which I had input cost only £10,000.


I was asked to lecture structures a few years after WWII when a Chair of Architecture was established at the U.W.A. As it was a daytime activity I had to obtain permission from the Public Service Commissioner. Quite a number of the students were Architectural cadets of the P.W.D Architectural Division so the request was granted. The position lasted several years, during the last two, 'smart ass' male students wanted to set their own agenda. I adamantly refused and started to treat them rather harshly to accustom them to the highly competitive and unscrupulous private practice. It was then that they threatened to get me sacked, I told them "Don't bother, I'm resigning".


The salary of post WWII Professional Engineers, the vast majority of whom were in Commonwealth and State Governments was pitifully small. When I married, my income only payed for food and one carton of cigarettes; nothing for bills – electricity, rent, council rates, taxes, water supply etc., so I registered a specialised design of a particular truss I called RIGITRUSS to be used for farm sheds which were in high demand at the time, the 2½% it payed in royalties doubled my Government salary. My wife's mentor Architect and a second similar Architect requested structures from her, which I designed under her auspices, earning yet another income stream. Because of a complaint by a private Engineer made to the Public Service Commissioner, I was forced to produce correspondence to and from my wife that explained the situation and engendered his satisfaction and approval! I personally never solicited any work away from any private consulting Engineer. In my opinion, it was because of this misconception that I was granted the Gleddon Travelling Scholarship that got me out of the country, travelling the world with my wife and three young sons for 20 months. It was during this period that the Engineers working for the Commonwealth took it to the High Court, which resulted in salaries of all Engineers being trebled.


During my time at P.W.D.A.D. I found that often the design process was controlled by 'Rule of Thumb' building codes produced by the Australian Standards Committee (of which I was the WA representative). Much later when I had comprehended the true value and action of internal force distribution in structures I realised that these 'Rule of Thumb' codes produced conservative and more costly structures than were necessary. This became apparent in the 'WIND CODE' for light tenuous structures such as farm sheds, as I will discuss later. I attended all committee meetings in NSW for the constant code reviews but discovered that if the Vic rep. scored an amendment against the NSW delegates, then NSW would move 'heaven and earth' to score the next one. Neither would countenance any of my proposals so, unfortunately, I stopped attending as I thought it was a waste of my time.


The Standards Association always kept up to date on the 'Standards' of various countries such as USA, UK, Russia etc. Several years later a NSW Professor, using wind tunnel experiments produced a 'WIND CODE' that I thought was spot on. But unfortunately he transferred to Canada where his code was promulgated. The Yank influence killed this code in preference for its own (which was in excess of the then Australian one) the result was the Australian code changed to align with the USA Standard, this led to an Australia wide furore by all light truss makers. I just laughed and ignored the Australian Code. Years before it came into effect I had registered RIGITRUSS (i.e. RIGID TRUSS PORTAL), an economical truss system that competed with the light farm building trusses built by an Australia wide firm who's designs did not even comply with the previous 'WIND CODE'. In my design the form trusses built had the top and bottom chords meeting at the column top, so creating a PIN joint allowing rotation, the RIGITRUSS had a lower bottom chord at column so creating a moment resisting joint. I also used a substantial 2 cubic foot concrete footing, which also produced a 'movement' resting force at column base whereas the aforementioned light trusses had a rather insubstantial concrete footing, which allowed column rotation.


The competitor's light trusses had virtual pin joints at four corners (base and eaves) and constantly blew over in storms whereas RIGITRUSSES had movement resisting capacity at four corners so it leaned a little but always stood proud during storms. I had sold the rights to RIGITRUSSES but had a royalty agreement of 2½% of truss construction costs, a few years after the war, when the economy picked up, this firm started to build the trusses and construct the buildings. They employed an enthusiastic salesman who travelled throughout the farming districts of W.A. from above to Geraldton to below Esperance, this enabled their yearly turn over to occasionally approximated one million pounds sterling. When this occurred my royalties equalled and sometimes exceeded my government salary. Even before the RIGITRUSS, I had developed, for a different steel fabrication firm, a system called Boucher's Building 'BENTS' were a 10 foot length of a triangular tapered truss could be manufactured in the hundreds and stored for instant supply to a purchaser. These 'BENTS' with a few small accessories could be assembled in differing column and truss formations to build farm buildings in spans of 20 or 40 or 60 or 80 feet. I also developed for them, a method of assembling the steel frames, with purlins and wall girts that attached with one of a two bolt connection, this allowed rotation while relatively flat on the ground, it also had universal joints at column to concrete footing so the whole assemble could be pulled into an upright position. Anchor(postwar) [:PlansDiagrams#bents:Click here] to see diagrams of Boucher's Building Bents.


Another of my early innovations was to introduce the use of reinforced brick lintels in all Government constructions in lieu of reinforced concrete or steel lintels, the steel rods bedded in cement mortar rather than lime. The reason for this was because, as mentioned previously, rusting steel increases in volume producing a force approximating 80tons per sq. inch. Cement is alkaline and when surrounding steel inhibits rust. The State Housing Commission, although not at my instigation, took up my method in all their housing construction evidently because the 'brickies' working on P.W.D.A.D. constructions also did work for the Housing Commission and brought the technology with them.


Later, to eliminate the expensive carpentry work in constructions needed for concrete and steel bar reinforcement in concrete beams and slabs (i.e., hooks and bends in both bars and stirrups) I introduced the FLAT SLAB construction. This is where concrete is poured onto a flat formwork and all steel reinforcement simply cut to length. Naturally this used more concrete and steel but because of reduced labour was actually cheaper over all. To increase the spans of flat slab construction, I later introduced the post-tensioned stressed concrete concept. I also designed and supervised the first post-tensioned concrete spiral staircase in Australia. The stressed steel cable end blocks were created using high tensile small rods formed into a tight coil and coated with high strength concrete, not the present high-tension steel cylinders.


The members of the Standards Association would not accept my claim that concrete constructions behave differently in W.A. to those in the eastern states, the climate in the east is much more humid so the buildings in the dryer W.A. would be more stable. I always provided gaps in long concrete buildings and in their outer brick walls. My experience was that concrete shrank 3/8" per 100 feet, brickwork grew ½" per 50 feet and that concrete grew or shrank approximately 2 to 3 months after a humidity change. To prove the latter I had meteorological instruments installed in one of the gaps of a long concrete building.


An example of brick growth and concrete shrinkage occurred in the USA. A 300 yard long Army Q. Depot storage building was constructed without any breaks in its length. A few years after construction, the shrinkage of concrete stretched the main bottom steel beam reinforcement past its yield limit and the building collapsed – This was years after I had introduced gaps in both concrete and brick government constructions. When flat plate construction in lieu of beam and slab was introduced in the eastern states several failures occurred here also, I put these down to bad workmanship and supervision. The Committee members completely ignored me and introduced excessive further provisions to the Australian Standards, which of course includes WA. I ignored these increases because I ensured good workmanship and supervision in all government jobs for which I was responsible.


During my tenure as Chief Engineer Structures for P.W.D.A.D, I would extract articles from Technical journals that detailed structural collapses of major structures throughout the world. After a wage appraisal for department heads, I produced thse articles to the panel adjudicating my appeal for a higher salary to prove that under my direction none of these events had ever occurred in any of my constructions that totalled $6 million plus yearly. The panel avidly viewed the articles, presumably because they assumed the collapses were caused by my negligence, however when the idiots realised their error they dismissed them and my appeal. It was only at the next review a few years later that I received a much belated salary increase.



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