The years from 1830 to 1860 saw the rapid transformation of great swathes of the English landscape as the expanding railway system made its mark on town and country. The population can hardly have failed to notice the awe-inspiring masonry and brick viaducts, along with dramatic cuttings and embankments and new iron bridges of various types that were appearing everywhere. Comparisons have been made with the building of the cathedrals, but each of those took a hundred, or hundreds, of years. The railways appeared almost overnight.
Some statistics serve to illustrate the magnitude of the early railway development. It has been estimated that during the most intensely active period of the mid-1840s, 250,000 men were involved directly in railway construction and another 750,000 were employed in the manufacture of materials for the new lines. Between 1830 and 1860, around 30,000 bridges were built, more than had existed in ‘pre-railway’ Britain.
A new specialism
To make it all happen a new breed of professionals had to come forward, both to survey and select the best route and to produce the detailed designs and specifications for the new infrastructure and then to build it all. These were respectively the civil engineers and the contractors.
Following the opening and successful operation of the Liverpool and Manchester Railway, for which George Stephenson was largely responsible, the die was cast and the promotion and building of the next major long distance railway routes was soon underway. The concept, surveying for, design, and supervision of construction was entrusted by the various railway companies to several engineers who began to make names for themselves.
Those in the forefront throughout this early period were Robert Stephenson, Isambard Brunel, and Joseph Locke. They are generally regarded as the great triumvirate, although, of course, there were many other engineers who made careers in the building of the railway system. Brunel was flamboyant and daring, which gave him striking successes and dazzling failures; Robert Stephenson was safe and steady; Locke was precise and workmanlike and, above all, he was careful with other people’s money. All three died in their mid-50s, a measure of the toll that their extraordinary workload had taken.
The majority of the early construction was accomplished by distinguished contractors, with Thomas Brassey, William MacKenzie, William Cubitt, and Morton Peto being prominent. It is striking that Thomas Brassey, for example, built one third of the railways in Britain and, by 1848, three-quarters of those then existing in France, as well as many projects elsewhere. But all the technical skills of the civil engineers and the planning and organisational skills of the contractors would have amounted to nothing without a vast dedicated labour force.
Gradients, earthworks, and the navvies
To achieve the almost level track formation required by the locomotives of the time, significant earthworks would be necessary. This became the main task of the ‘navvies’ and why there was a need for them in prodigious numbers. The work and living conditions for these men were undeniably extremely tough and safety was of low priority, but it seems that the contractors had no difficulty in recruiting sufficient labour for building those first main lines.
The scale of earthworks required became less demanding with the advancement in locomotive design and capability. For 85 miles out of London, Brunel’s line to Bristol was laid almost dead level. Similarly, the first London to Southampton line, built by Joseph Locke and opened in 1840 was only achieved by some stupendous cuttings between Basingstoke and Winchester. At the time, this line was regarded as severe compared to the Great Western, with one gradient of 1 in 250 running for 17 miles. By contrast when the Portsmouth line, through similar country, was completed only 20 years later, the engineer permitted gradients of 1 in 80 and the line was carried through the South Downs with few major earthworks. This was certainly due to the improvements in locomotives made in the 1850s and 1860s. Locke tried to avoid tunnels if at all possible. He was confident of building the railway over Shap and through the Southern Uplands with severe gradients of 1 in 75. He was responsible for most of what is today’s West Coast Main Line north of Birmingham and there are no tunnels from there to Glasgow.
There is no better example of the rigours endured by the navvies than those encountered in the building of the first Woodhead Tunnel. The single-track tunnel, bored through the Pennine summit for the line being engineered from Manchester to Sheffield, was built between 1839 and 1845. The work was dangerous and miserable. Water ran down the sides of the tunnel, which was generally ankle-deep and sometimes knee-deep in mud. It cost the lives of 32 men and seriously injured over 200.
A local surgeon, Henry Pomfret, lived about eight miles away and went up to the tunnel three days a week to treat the injured. He also made himself available ‘on call’ to respond immediately to accidents. It is of significance that he was not retained by the railway company or the contractors but by the men themselves, who paid so much a week as voluntary contributions.
Thomas Brassey and William Mackenzie secured a contract for the Paris to Rouen line in 1841, for which Joseph Locke was the engineer and needed to recruit labour locally. Brassey’s loyal British workforce were keen to take on this new challenge, but he was reluctant to take too many of them away from his ongoing contracts at home. So, he took on many French labourers, to work alongside their British fellows. This led to some amusing situations.
The British navvies were scathing about their French colleagues, scorning the wooden shovels and basket-sized barrows which the French peasants brought to work, themselves using picks and heavier shovels. Locke said that he had often heard French workmen around a group of navvies exclaiming: “Mon dieu, ces Anglais, comme ils travaillent” or rather, “My God, those English, how they work!”
New methods
The new and particular requirements of the railways led to a previously unprecedented acceleration in the science and practice of civil engineering.
As the industrial revolution in the UK took off towards the end of the eighteenth century and the start of the nineteenth, the need to improve roads and the building of the canal system were the prime drivers of civil engineering as a recognisable and specialised profession. However, the technical knowledge and skills required to create these particular infrastructures were, with one or two exceptions, simply the development of traditional building practices that had been used for many centuries. They could be built with confidence by practical men, mostly without formal education or training. Also, there was not much need for a mathematical approach to the theory of structures or to understand their exact predicted behaviour under various loading conditions.
Another difference between the design and layout of the other forms of transport infrastructure prior to that needed by the railways was their more modest need of significant structural work. For example, canal promoters were satisfied with allowing their routes to follow contours as much as possible. Only where a great diversion or additional route length would otherwise be necessary were lock flights or tunnels budgeted for. Railways, in contrast, needed more direct alignments and minimal gradients.
Apart from locations where the proposed route lay in lowland or could easily follow the course of a river valley, major earthworks were required in the various forms of cuttings and embankments. Where the terrain to be traversed was such that the scale of the earthworks would be uneconomic or impractical, then major bridges, viaducts, and tunnels had to be designed and built. While recognising that construction of the canals necessitated the labour of thousands of navvies to excavate vast quantities of material, as did in their turn, the railways, there was a limited need for the design of innovative structures. The Grade 1 Pontcysyllte aqueduct carrying the Llangollen Canal across the Dee Valley is a notable exception to this observation. Designed and built by Thomas Telford and opened in 1805 it has UNESCO World Heritage Site status.
Railway structures required the proper understanding of the behaviour, performance, and limitations of the materials used and of loading. An empirical approach to this seemed adequate initially and, with the knowledge available at that time, was all that was possible in the early days. Quite soon structural theory was developed and applied by the engineers charged with the design and construction of the rapidly expanding railway system. That this new approach was needed was, unfortunately, confirmed by one or two high profile structural failures.
Lessons learnt
The failure of the viaduct over the Tay estuary in 1879 is the most famous disaster to befall early railways. Designed by Thomas Bouch, it had been completed only the previous year. There were defects in workmanship and inspection, but its downfall was largely that the need for adequate wind bracing had not been properly appreciated.
Regrettably, Robert Stephenson’s bridge over the River Dee near Chester also had a short life and almost ended his career in 1848. Here the problem was the failure in tension of one or more of its cast iron beams. Stephenson had incorporated wrought iron ties with the intention of relieving the tensile forces, but the subsequent inquiry found that they had not functioned as intended and may even have made the situation worse. This accident made engineers even more wary of using cast iron than they already had been, except for bridge components clearly in compression throughout their cross-section, such as evenly loaded columns and arch ribs.
Less well known is the collapse on 19 April 1845 of an almost-complete masonry viaduct at Stalybridge with the loss of 18 lives. The contractor had built the piers largely with unmortared rubble encased in a thin dressing of stone.
A happier example of structural failure with an honourable outcome was the failure on 10 January 1846 of the 27-arch, 100-feet-high, curving brick Barentin Viaduct, when nearly finished on the line between Paris and Le Havre. Fortunately, there were no injuries.
Thomas Brassey, the contractor, visited the site and determined that the failure was caused by being erected too quickly, in wet weather, and with poor lime. He took immediate responsibility and offered to rebuild the structure completely at his own expense of £40,000. In his report to the directors, he said: “I have contracted to make and maintain the road and nothing shall prevent Thomas Brassey from being as good as his word”.
Both these viaducts had been designed by Joseph Locke, but these misfortunes had no long-term effects on his career, nor that of Brassey and they often worked in partnership.
Choice of materials
Joseph Locke eschewed the use of metal for bridge construction and preferred to build in masonry wherever possible. There are many notable viaducts to his name, such as the 1837 Dutton Viaduct over the River Weaver on the Grand Junction Railway. Other engineers made greater use of cast iron and wrought iron as appropriate.
Isambard Brunel built many impressive viaducts using timber for the Great Western’s extensions into South Devon and Cornwall. He chose this material as it was uncertain how much traffic these routes would attract, and so he recommended to the railway directors a more modest outlay of capital expenditure initially. He had found a source of yellow Baltic pine, with a reputed lifespan of 30 years. This was borne out. Of the 67 viaducts built between 1848 and 1864 many were not replaced until the 1880s or even into the 1900s. Metal decks were installed in place of the timber and, in some cases, new masonry piers.
The Institution of Civil Engineers
The Royal Society had been in existence for some time, enabling the sharing of scientific knowledge and progress. But young civil engineers needed a similar forum to promote the exchange of ideas and information. Thomas Telford was the undisputed head of the small family that made up the engineering profession.
Unbeknown to him, a group of eight young engineers led by Henry Robertson Palmer had launched the Institution of Civil Engineers at a meeting on 2 January 1818. Telford was invited to become its first president in 1820 and remained so until his death in 1834.
The railways were a boon to the civil engineering profession, rapidly broadening its experience and opportunities. Equally, the Institution fostered rapid advances in railway design and construction techniques.
Early triumphs
From the many magnificent assets created in the railway’s early years, it is invidious to mention only a few. But some deserve selection because of the ingenuity deployed in their design and construction, the challenges overcome to actually build them, or by virtue of their dramatic appearance or longevity.
Robert Stephenson’s tubular Britannia Bridge over the Menai Straits was the larger cousin to a similar bridge with the same principles used to cross the Conway, gaining their strength from the box sections of wrought iron. What particularly distinguishes the Britannia Bridge is the method of erecting the tubes by floating them out and jacking them up through guide slots in the masonry piers. This process was fraught with risks and was not successful on the first attempt, despite a very large crowd of spectators!
It is inspiring to read in detail about the hurdles that Stephenson had to overcome and the heavy mechanical lifting and manipulation techniques devised to eventually get the tubes into position. Brunel had travelled to the site to observe the operations and to support his friend. Stephenson was later able to reciprocate when Brunel was having great trouble in completing his Great Eastern ship in London. Stephenson was ill and unable to travel to the site, but his written suggestions were conveyed by courier. This is illustrative of the friendship and collaboration that existed between several successful engineers of the day.
Similar feats, with some slight differences, were later achieved by Brunel in constructing his famous and magnificent Royal Albert Bridge over the Tamar at Saltash, taking the railway into Cornwall for the first time.
Robert Stephenson’s High Level Bridge over the River Tyne at Newcastle, carrying the railway on its upper deck and a roadway at the lower level was under construction between 1847 and 1849. During this time, the Dee bridge failed. This must have given Stephenson serious pause for concern, as the primary structural arch members for the High Level Bridge were of cast iron. However, the relatively slender piers supporting each of the five spans were not adequate to resist the lateral thrust from the arches and so he had incorporated wrought iron tie beams to form bowstrings to carry the arch reactions as tensile forces.
The Forth Bridge designed by Sir John Fowler and Sir Benjamin Baker, built by William Arrol, and opened in March 1890 is surely the supreme achievement in the contribution of civil engineering to the expansion of the railways. It was the first major use of mild steel for bridge construction – 55,000 tons in total.
There are many other major feats of civil engineering in the nineteenth century which are not readily in public view. To reach the Channel ports, the South Eastern Railway took an easy route across the Vale of Kent until it reached Folkestone in 1843. The remaining seven miles to Dover meant tackling the chalk cliffs. William Cubitt, somewhat a hybrid between engineer and contractor was sufficiently confident about the stability of the chalk that he bored Abbotscliffe and Shakespeare Tunnels quite close to the exposed cliff face.
Another example, out of sight but of great importance, is the Severn Tunnel, completed between 1873 and 1885 with many problems of water ingress making construction very difficult. Pumping is still required today.
After the railway mania subsided in the 1860s, with far more schemes given Parliamentary approval than were ever built, the only major works towards the end of the Victorian era were the Settle and Carlisle Railway and the Great Central Railway. Railway civil engineering in the UK then became largely one of maintenance and renewal for over a century, until, that is, the construction of the Channel Tunnel, HS1, and now HS2.
Meanwhile, worldwide, the British engineers who had founded the UK railways were soon advising for and building railways across the globe.
The future
Worldwide, there will continue to be a demand for new routes, especially high-speed passenger lines and new freight lines for exporting minerals and for container traffic. All will require a significant civil engineering input with opportunities for innovative structural designs. These will, no doubt, aim to satisfy carbon targets in the choice of materials and use ever-improving methods of construction – for example, taking advantage of pre-fabrication of bridge, viaduct, and tunnel units off site wherever possible – giving better worksite safety.
For the UK, with its particular geology and climate, there will need to be ever more attention given to earthworks. Embankment, cutting, and sea defence failures have caused operating problems and risks ever since they were built. In future, a much larger budget for preventative work will be required. The effects of climate change have begun to show clearly how essential this will be, and such an approach is already well underway.
A challenge for railway civil engineers of the next few decades will be to devise monitoring and predictive tools to target investment in the most effective way and to design and install permanent solutions to the geotechnical problems which they will face. It seems fitting to round off this article celebrating 200 years of railway civil engineering by being reminded of those momentous earthworks created almost entirely by the herculean effort of men and horses.
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