The 1950s was a watershed decade for civil and structural engineers.
Dave Parker looks back at the key developments, and the blind alleys, which shaped today's industry.
For young engineers starting their career, 1950 was a very good year to begin. Optimism was back in fashion. The physical damage of the war years had largely been made good, materials rationing was less restrictive, and new warproven technologies promised ever more efficient structures.
All over the country, plans for new infrastructure that had been gathering dust for a decade or more were being taken down from the shelf and put back on the agenda. Bridge builders and tunnellers were eyeing the remaining barriers to communications around the UK - estuaries and firths, Thames, Humber, Tyne and Severn, Forth, Tay and Cromarty. Roadbuilders studied maps and linked Britain's cities with car-friendly networks in blue Roman pencil.
It was a time for dreams.
High priority projects like power stations and the coal industry had first call on supplies of structural steel. But there was no shortage of cement, thanks largely to the industry's persuasion of pre-war governments that cement works in the South East would be top of the Luftwaffe's target list.
Production went into overdrive and mountains of cement clinker were built up, but the attack never came.
It is also rumoured that some junior civil servant renewed a long term contract for the supply of the high tensile steel cable used to moor barrage balloons shortly before the war ended.
So there was no rationing of what became an essential component in the 'new' material; pre-stressed concrete.
In itself, the idea of precompressing a concrete element so that no part of it ever underwent tensile stress was no novelty.
Pioneered by EugÞne Freyssinet in France in the 1920s and introduced by him into the UK in 1936, the technique was first adopted by the Ministry of Transport in 1940. A factory was set up at what is now TRL to produce standard pretensioned prestressed beams to repair bomb damaged bridges. Prestressed rail sleeper production began in 1949.
The technique, however, really began to flower after the 1951 publication of First report on prestressed concrete by the Institution of Structural Engineers, an official, if provisional, seal of approval. Its efficiency and economy was perfectly in tune with the professional zeitgeist. Production of factorymade pretensioned prestressed concrete structural components soared, designers began to develop greater confidence in working with post-tensioning on site.
The 1950s, more so perhaps than any since, was the decade of concrete. Concrete was sexier, more exciting then. Concrete structures were the most innovative, concrete architecture won the most awards. Concrete, engineers were taught, was a homogeneous, user-friendly material with a track record dating back thousands of years.
Durability? No worries, said the Cement & Concrete Association. Just look at the Parthenon.
And most believed. Of all the lobby groups ever created within the construction industry, the C&CA was the undisputed champion. Very few engineers ever realised it was funded by the cement producers, which operated an entirely legal price ring for many decades. Wellfunded, well-equipped, and staffed by high quality researchers and engineers, the organisation underpinned the unquestioning fascination with concrete technology.
Some of the more exciting possibilities turned out to be dead ends. Thin concrete shells and folded plate roofs depended as much on the skills of the craftsmen who fabricated the complex timber shuttering as on the tedious analyses performed by the designers working with no more aids than a slide rule and a set of log tables. As these craftsmen died out or found better paid jobs there was no following generation to replace them. In the end it was simplicity, repetition, right angles and sophisticated factory-produced formwork that took concrete building construction into subsequent decades.
Other materials had also received a boost from wartime developments. Weather resistant resin adhesives replaced milk-based casein wood glues, and laminated timber suddenly became a predictable and durable structural material. Glulam roof trusses became something of an architectural cliché after their showcasing at the Festival of Britain. Aluminium, however, was not so fortunate (see p21).
Welding seemed set to take over from riveting after the war - but it was a slow revolution. Large steel trusses were still being riveted at the end of the decade.
A fortunate few, engineers based mostly in or around London's Victoria Street or Fitzrovia, continued to push back the frontiers. A fresh wave of hydroelectric power projects in Scotland - including the world's first post tensioned concrete dam - spurred analytical techniques, including photo-elastic stress analysis. Soil mechanics was becoming accepted as a serious and respected discipline.
Computers were still near-mythical creatures lurking in the closely guarded basements of military and government institutions but some were beginning to escape. The more far sighted were already dreaming of a future where structures and estuaries alike could be modelled in ever greater detail, when analyses that once took months could be completed in days.
No-one then, not even science fiction writers, could conceive of a future where draughtsmen were an extinct species and computers had evolved from cosseted temperamental mainframes the size of a London bus into temperamental desk top boxes. Then, advanced analytical technology meant a funnyshaped slide rule, circular or cylindrical rather than flat.
Then, as now, reality for most civil engineers tended towards the humdrum. Even on the large power station and docks projects the engineering was little different to a that of a decade earlier. Sewage treatment works, road maintenance and flood alleviation were the everyday experience - but engineers still dreamed.
During the next decade some dreams, like system-built tower blocks, eventually turned out to be nightmares. But the foundations of the modern world were laid down in the 1950s, and, for better or worse, it is upon those foundations that the current generation of civil engineers still depends.