The A8/M8 joins the Glasgow motorway at the Baillieston interchange. This extensive four-level structure incorporates two interchanges and provides links between the M73 and M8 (Monkland motorway), the M73 and A8 and the M8 and A89. The whole interchange covers some 55 hectares and includes 21 concrete bridges. It was officially opened in April 1980 by the Rt Hon. George Younger.

M8 in Glasgow
After World War II plans began to be formulated in Glasgow for major new roads including urban motorways. One of the first steps in implementing improvements was the construction of the Clyde Tunnel and its approaches, both tubes of which were opened to traffic in 1964. To provide a systematic and comprehensive approach to road planning the Glasgow City Corporation in 1960 appointed consultants Scott Wilson Kirkpatrick and Co. (Scotland) to prepare a Highway Plan for Glasgow; William Holford and Associates (Glasgow) architects and planning consultants were appointed as part of the design team. A plan which set out a network of roads required for traffic growth to 1990 and beyond was adopted by the Corporation in 1965 and 3 years later was incorporated into the Greater Glasgow Transportation Study Forecast and Plan. Implementation of the plan was put in hand and the main objective of the programme up to 1980 was to establish an east-west motorway route across the city connecting the western section of the M8 to the A8 and M73/M74. The route consists of the Monkland motorway, the north and west flanks of the inner ring road and the Renfrew motorway. Construction of the last section of this motorway route was completed in 1980 and opened officially by the Secretary of State for Scotland in April that year.

The Monkland motorway was designed and supervised by the Strathclyde Regional Council Department of Roads (Glasgow Division). Construction was in stages the first being from Townhead interchange on the inner ring road to Cumbernauld Road (A80), the second from the A80 to Stepps Road and the third from Stepps Road to the city boundary where the motorway joined the trunk road section leading to the Baillieston interchange. That section of trunk road and the interchange were constructed for the Scottish Development Department. Contractors engaged in various stages were Costain Civil Engineering Ltd, GKN Foundations Ltd, and Whatlings Ltd.

The line chosen for the inner ring road motorway follows fairly closely that of the old Monkland Canal which had to be drained. The existence of the canal had created a boundary to areas for over a century and severance problems arising from building the motorway were thus minimised.

Considerable engineering problems were met on the second stage of the motorway because of poor ground conditions. Sixteen old mine shafts had to be secured and some 320,000 cubic metres of peat were removed where the line of-the motorway crossed a peat bed of up to 7 m in thickness.

The North and West Flanks
The North and West Flanks of the Inner Ring Road were constructed in four major contracts, the last of which was the Charing Cross Section. This final project integrated the other three into a completed by-pass of the City Centre to form the first part of a continuous motorway route from east to west through Glasgow, which was the major element in the 1975 highway target programme.

Glasgow was at the time engaged upon a massive programme of redevelopment of areas of sub-standard or obsolescent housing, commerce and industry. The programme was approved in the 1960's. It included ten Comprehensive Development Areas forming an almost complete ring around the City Centre, which created the opportunity to build an Inner Ring Road to solve the growing central area traffic problems.

In 1960 Scott Wilson Kirkpatrick and Partners were appointed Traffic Consultants to advise on and prepare definitive designs for such a road. Their reports were submitted to the Corporation in 1962, and in 1965 when the Corporation approved the construction of the North and West Flanks of the Inner Ring Road. Thereafter, Scott Wilson Kirkpatrick and Partners were appointed Consulting Engineers for the detailed design of the North Flank, in two major sections. The first stage of the Townhead Interchange was the first of the four major contracts. This work commenced in December, 1965 and was completed and opened to traffic in April, 1968. The Woodside Section completed the North Flank, when it was opened in May, 1971.

W. A. Fairhurst and Partners (who had previously been asked to report on the engineering feasibility of a bridge over the River Clyde at Kingston) were appointed Consulting Engineers in 1962 and were instructed to proceed with the detailed design of the bridge and its approaches as an integral part of the West Flank of the Inner Ring Road. Their remit was further extended to include the design of the whole of the West Flank. The Kingston Bridge and its approaches were opened in June 1970 by Her Majesty the Queen Mother.

The construction period for this major phase of the Highway Plan for Glasgow therefore lasted just over six years from December, 1965 to January, 1972. From conception to completion there was a period of over ten years, These long time spans indicate how slow is the process of urban redevelopment, involving an enormous amount of rehousing, and relocation of industry and commercial undertakings, the success of which depends upon the co-operation of many Departments of the Corporation.

The opening of the Charing Cross Section released more of the potential traffic capacity of the previous three sections. This facilitated traffic flows on the Inner Ring Road but also improved the Central Area environment by re-routing traffic away from City Centre streets.

The total length of the North and West Flanks is approximately 2½ miles, and the cost totalled £26.893m including £21.269m. for construction work and £5.624m. for land. Alterations to Public Utility Services formed a high element of cost, amounting to almost £850,000. In the Charing Cross Section, Highway powers were used for the acquisition of land and properties. The major part of the route however, passed through Town head, Woodside, Cowcaddens and Anderston Cross Comprehensive Development Areas where the Planning Acts were applied for this purpose. The total number of houses demolished by the Corporation Building Department was 4,481.

The Townhead Interchange
The picture shows the relation of Stage I of the Townhead Interchange to surrounding development and redevelopment, and provides a general view of the project and its associated landscaping.

This scheme was the first stage of the Interchange formed by the junction of the Springburn Expressway, the Monkland Motorway and the North and East Flanks of the Inner Ring Road. It consists of about 5,000 feet of dual carriageway over Castle Street which is the main north/south route on the east of the City Centre. On its western extremity it connects with the Woodside Section of the North Flank and on its eastern extremity through a temporary ramp to Alexandra Parade and thence to the Edinburgh Road.

The complexity of Stage I derived not from its current function but from the provision for its future extension which necessitated the construction of ten bridges, six pedestrian subways and thirteen retaining walls. Where possible, structures provided for future works were brought into immediate use by temporary connections.

One of the major problems in landscaping Townhead was the temporary treatment of areas cleared in advance for future works.Where possible final landscaping treatment was incorporated, elsewhere if disturbance was deemed to be unavoidable in implementing the future works the affected areas were temporarily formed and grassed.

A feature of the landscaping was the footpath system. This could not be fully developed until the completion of the whole interchange, but innstage 1, 5,600 feet of paths, independent of those immediately alongside surface streets, interconnected the underpasses and footbridges. This was planned as a deliberate attempt to open, rather than sterilise, the area of the interchange.

The initial traffic flows on the Townhead Section of the North Flank were measured in 1968 at 14,000 vehicles per day as compared to the predicted figure of 19,000 vehicles per day. This flow increased to 24,000 vehicles per day following the opening of the Woodside Section in May, 1971.

It can be seen from this map, that the interchange has now been developed extensively since its original opening. More details of the current layout, together with several excellent pictures, can be seen on this website. There are similar descriptions and pictures of other junctions on the M8 accessible from the same link.

The Woodside Section
Edinburgh-Glasgow2The aerial view shows the Woodside Section from its interchange with Great Western Road at the junction of the North and West Flanks to its connection with the Townhead Interchange Stage I. As with Townhead, the scheme lay almost wholly within areas of new development of which the two most significant are Cowcaddens and Woodside Comprehensive Development Areas. The extensive cleared areas lying to the immediate north of the scheme were in process of redevelopment. The fringe commercial centre of St. George's Cross which contains an underground station had been partially by-passed by the new scheme. Final plans for the centre envisaged complete pedestrianisation with sufficient parking to provide a useful "park and ride" service via the underground to the centre. The station reception area and entrance had been rebuilt with this proposal in mind.

As with Townhead, a great deal of the complexity of Woodside was necessitated by provision for a future interchange, in this case the connection of the Maryhill Motorway to the North Flank. The area cleared for this interchange can be seen in the aerial view as can also the ramp platform from which the north carriageway of the North Flank will be extended into the Maryhill Motorway. Woodside consisted of about 4,000 feet of dual carriageway motorway, and about 3,500 feet of surface streets, together with seven vehicular bridges (including two viaducts) two footbridges, two pedestrian subways and eleven retaining walls.

The viaduct sections were respectively 1,200 and 1,500 feet in length and consisted of precast post-tensioned beams supported on inverted "T" reinforced concrete pierheads. This form of construction was most consistent with the necessity to maintain traffic on New City Road and Garscube Road, both of which carried heavy traffic flows under the viaduct throughout the contract, and with speed of erection. A feature of the retaining walls was the use of precast exposed aggregate panels as both formwork and permanent finish.

The same close attention has been paid to the pedestrian system and to landscaping as with Townhead. Again almost all of the contiguous land was in process of or scheduled for redevelopment. While this facilitated a finally more satisfactory integration it created interim problems. As with Townhead a policy had been followed of installing the maximum of finished landscaping and where disturbance is inevitable in future work, forming and grassing for the interim period. This was regarded as a necessary on-cost if blight was to be avoided.

The Charing Cross Section
Edinburgh-Glasgow3The opening of the Charing Cross Section of the Inner Ring Road brought to a conclusion the first major stage of Glasgow's Highway Plan. This three-quarter mile length of the West Flank linked the Kingston Bridge to the two stages of the North Flank (Townhead and Woodside to give an L-shaped by-pass to the City Centre.

Set between the steeply rising ground of the Park Circus and Garnethill areas, the site had a very prominent position in the City among fine Victorian buildings and the new private developments.

In many ways this particular contract was one of the most demanding urban motorway projects undertaken in the United Kingdom. Its location-through one of Glasgow's busiest commercial areas-has meant coping with heavy volumes of both vehicular and pedestrian traffic at all stages of construction. This, together with the problems posed by dealing with a multiplicity of services, working close to existing buildings, limited working space, varying ground conditions, noise, dust and vibrations, etc. has necessitated extremely careful planning and attention to detail on the part of both the Engineer and the Contractor at all times.

The motorway geometry was determined by the need to link to the interchange at St. George's Cross and to the Kingston Bridge Approaches and to make use of the existing North Street as a longitudinal surface distributor road. The original surface street pattern at Charing Cross was modified to improve the flow of traffic and to cater for motorway access.

The alternative possibilities of constructing the motorway in an elevated form or in a cutting between retaining walls were investigated and costed. The former would have been slightly less expensive-mainly because of the lesser impact on services. However, when the importance and general amenity of the area as a whole, and buildings such as the Mitchell Library in particular, were taken into account, a depressed form proved more acceptable.

The Inner Ring Road was designed to urban motorway standards with an operating speed of 50 mph.

Contrary to what is the case on most contracts, the retaining walls provide much of the interest. The main interest lies in the motorway retaining walls which are somewhat unusual in their design. Sheet pile walls with rock anchors have been used on several occasions as a temporary construction expedient, particularly in deep basement constructions. Their use, however, as permanent walls was much more limited. The advantage, in this case, of minimising the construction effects on services, traffic and existing buildings showed considerable savings.

Since high levels of noise and vibration could not be tolerated, the Taylor Woodrow Pilemaster was used to drive the 2,500 tons of steel sheet piling on the Contract.This piling is of 3N or 4N section, much of it in high yield steel. For the majority of the walls two rows of rock anchors were driven. The anchors (which were formed for the main contractor by Foundation Engineering Limited) comprised tendons, with load capacities up to 126 tons, of p.v.c. covered, grease filled, ½ in diameter Dyform strand. The specially fabricated anchorage head was incorporated in double channel continuous walings. In situ concrete and shaped precast facing panels give the walls an acceptable finished appearance.

The Contract had a large structural content. Apart from the long lengths of retaining walls, there are several bridge structures, all of which had their own particular demands.

Limited track possession times dictated that the busy electrified low level railway at Charing Cross Station had to be bridged with precast prestressed beams. These box beams are 80 ft. in length and bridge the track on two levels-one for the motorway itself and the other for a parallel surface street.

Two of the motorway ramps were carried on in situ prestressed concrete box structures. One of these is a 5 x 60 feet span viaduct and the other a varying depth bridge on two spans of 54 feet and 120 feet.

The Bath Street Bridge and the tunnel which carries the complex of surface streets at Charing Cross were of reinforced concrete slab construction incorporating the miscellany of service pipes and cables which are inevitably a feature of this type of work. The 450 feet long tunnel, built in "cut and cover", was constructed in three defined stages to suit traffic and service layouts. The walls were finished in white mosaic tiles, the roof had a dark blue painted finish and lighting provided by cornice mounted fittings. The cost of the tunnel and associated works was around £½m.

Pedestrians and vehicles were carried on separate grades at Charing Cross and the first two of the necessary footbridges were included in this Contract. A five span bridge in prestressed concrete links Woodside Terrace and Woodlands Road with Renfrew Street. On the south side of Sauchiehall Street, a 50 feet wide slab, spanned the Ring Road and surface streets and eventually carried a two-storey development and a walkway.

Road construction comprised either a flexible base of bituminous macadam, a concrete base or a regulating concrete layer on rock, the form depending on the type of sub-strata which varied along the length of the Contract. The running surface consisted of 4 inches of hot rolled asphalt placed in two layers.

Most of the lighting was obtained from lanterns on 100 feet high masts and ramp heating was provided on ramps where the gradient exceeds 5 per cent.

The median barrier, which was designed to flex, under impact, as a longitudinally tensioned rail, comprised a steel box section with weak post to rail connections.

Major signs on the motorway were of the internally illuminated gantry type evolved for use on the whole motorway system.

The finishes to the structures and other works was chosen to minimise maintenance costs and to accord with the importance of the location of the Works. The final appearance was enhanced by the landscaping works carried out by the main contractor and the Corporation's Parks Department.

The Kingston Bridge
Edinburgh-Glasgow4No story of the motorway era in Scotland would be complete without revisiting the Kingston Bridge in the centre of Glasgow, and its problems. This structure has been carrying the 10 lanes of the M8 over the River Clyde since 1970. As a 3-span in situ pre-stressed concrete box girder bridge, its life has been hard and it has suffered from a number of problems: rotation of the north abutment; bearing failures; and, mid-span sagging. Responsibility for the bridge transferred from Strathclyde Regional Council (SRC) to the then Scottish Office along with the rest of the Glasgow motorway network as part of the trunk road review undertaken with Local Government Reform in 1996. Immediately before this change in responsibility, in March 1996 SRC had awarded the contract for the major strengthening works to Balfour Beatty Limited. Jim Innes, who had just taken over as Director of Roads from John Dawson, was faced with the problem of how to progress these repairs without disrupting the 150,000 vehicles which crossed the bridge each day. To retain the knowledge built-up by SRC's engineering staff who had transferred to the new Glasgow City Council under Alistair Young, the Secretary of State appointed the Council to act as Agent for the remedial works programme. In Autumn of that year, a similar type of bridge in the Pacific republic of Palau collapsed into 30m of water following a major strengthening contract. This prompted an in-depth review of the strategy for Kingston Bridge. The proposed works included the installation of additional post-tensioning in the bridge deck and lifting the deck using a computerised jacking control system and supporting it while the piers and bearings were replaced. A fundamental requirement was for the client, engineer and contractor to agree performance criteria which would ensure that the bridge remained within safe limits at all times. No comparable bridge repairs had ever been carried out and the detailed design, checking and testing of the jacking control system proved to be exceptionally demanding.

The strengthened deck was lowered on to the new supports in August 2000. All of this was accomplished with just 3 weekend bridge closures. Very few bridge users knew of the innovative nature and extent of the civil engineering works that were in progress under their wheels or that for 10 months they were driving on a bridge deck supported on jacks. The ingenuity of the engineers and contractors who delivered this challenging project has been recognised by award of the 2001 Saltire Award for civil engineering excellence in Scotland and the prestigious ICE Brunel Medal.

On completion of Target One it was possible to compare actual traffic flows with those originally predicted and they were found to be close. In 1980 the traffic flow on the Kingston Bridge had reached 111,000 vehicles per day (about the originally designed capacity). The original plans had called for the completion of the Inner Ring Road by 1980. This would have lead to a large reduction in traffic on the Kingston Bridge and the north and west flanks of the Ring Road due to diversion of traffic to the south and east flanks of the Ring Road. In the event the traffic flows on the Kingston Bridge have continued to grow (along with the rest of the M8) in line with the growth in vehicle ownership, reaching 152,000 in 1991. The Kingston Bridge Section of the West Flank was opened by Her Majesty the Queen Mother on 26th June, 1970, and during most of its existence has probably been the busiest road in Europe.

The Renfrew motorway
Edinburgh-Glasgow5The Renfrew motorway continues the M8 westwards from the inner ring road at the Kingston Bridge to the former city boundary at Shieldhall Road. A main purpose of this section of the M8 was to provide a fast route to the Abbotsinch Glasgow Airport and also to serve industrial developments at Linwood. Construction was carried out in two stages and the motorway has dual three- and four-lane sections in places. Much of the route is elevated above the surrounding countryside and in a westerly direction gives views of distant mountains.

The most significant structure on this section of the M8 is the 2,700ft long White Cart viaduct. The steel box-girder viaduct was carried on 4ft simple octagonal shaped concrete piers. The 115ft suspended spans were assembled in a Clyde shipyard and towed to the site before being lifted into position from the ends of the main cantilevers before final positioning.

Poor ground conditions meant that structures had to be supported on piles. A particular problem arose when it was found not to be possible to drain the motorway into the existing drainage system and a new outfall sewer from the motorway to the River Clyde had to be constructed.

Edinburgh-Glasgow6Parallel to the Renfrew motorway on the north side of the Clyde is the Clyde expressway which connects the north end of Kingston Bridge to the north approaches to the Clyde Tunnel; the southern end of the tunnel connects with the Renfrew motorway at Cardonald interchange. The expressway is mainly grade separated but is not built to full motorway standards. It was designed by Sir William Halcrow and Partners, built by Balfour Beatty Construction (Scotland) and opened in April 1973.

In the 1960s Glasgow City Corporation had collaborated with the Road Research Laboratory in the development of an area traffic control system based on central computer control, and as the motorway system took shape it became necessary to consider wider aspects of control embracing not only the ordinary streets but also motorways and expressways. In 1975 the Transport Operations Group of the University of Newcastle upon Tyne were appointed to advise on a central integrated control system for Glasgow. As a first step it was decided to install an interim motorway control and television surveillance system centred on Strathclyde police headquarters, and this was commissioned during 1980.

Construction of the motorway system in Glasgow has involved major capital investment and it is important to know what impact that has had on the city. Cullen has attempted to make an assessment of certain of the impacts and he concludes that some of the effects of the motorway in 1980 are:

reduction in total travel time within the city of about 18%
fuel saving of about 9%
reduction of 1312 injury accidents
first year rate of return on investment of 15.6%
a ratio of discounted present value of economic benefits to discounted present value of costs of about 2.5
environmental benefits arising from transfer of traffic from old roads to the motorway routes
pedestrianisation of principal shopping streets
improvements to bus operations.
Bishopton by-pass.
This by-pass continues the M8 westwards from the Renfrew by-pass to Westferry Lodge some 6 miles away. From thereon to Port Glasgow the route is all-purpose dual carriageway.

The by-pass was built in two stages; the first included the approach roads to the southern end of the Erskine Bridge A898(M) across the Clyde which at its northem end links with the A82 Glasgow-Inverness trunk road. This first stage was opened in December 1970, a few months in advance of the official opening of the bridge. The 3½ mile second stage was delayed by procedural and other difficulties, e.g. statutory procedures fixing the line of route were held up until the report of the Clyde Estuary Working Group was available. After the completion of the by-pass residents in Bishopton complained that they were cut off four direct access to the motorway and had to make an appreciable detour to reach it. The SDD pointed out that side road closures had been made in the interests of safety and traffic. The by-pass reduced traffic on the A8 through Bishopton by 80%.

Contract details