Despite adverse weather creating challenging working conditions in February, bridge beam lifting operations at Gelly overbridge were successfully completed during two overnight closures of the A9 on 18 and 19 February, rather than the three nights originally planned. The project team were able to carry out the finishing works to the beam lift operation on the third night under temporary traffic lights, which minimised disruption to road users allowing the road to remain open overnight on the 20 February.
In addition, the project achieved a significant milestone during February with traffic being switched on to the new section of northbound carriageway at Luncarty Junction for approximately 2.4km. The focus will now shift to the new southbound carriageway at the northern end of the project.
During Winter 2019/20, the project team have been busy laying cement bound granular material (CBGM) as the base of the new southbound carriageway.
Work also continued on the installation of the drainage network, tying in new road drainage to the network of Sustainable Drainage System Ponds (SuDS) that have been constructed throughout the project, some of which are now visible to passing road users.
Earth moving operations continued at Bankfoot North Junction during January and February with some 27,000m3 of earth placed in the vicinity of the new Hunters Lodge Underbridge extension. This material is being excavated from other areas within the site to fill the area surrounding the structure.
The construction of the concrete bridge decks at the Pitlandie and Coltrannie overbridges, following their beam installation in late 2019, has also progressed within the period. The concrete deck at the new Stanley/Tullybelton overbridge was completed allowing site traffic to transport material over the A9 without affecting road users.
Landscaping works also got underway and road users and residents will have noticed that several hundred trees have now been planted on the verges and slopes adjacent to the newly constructed carriageway.
During Autumn 2019, the project moved into another exciting phase with the first layers of the new road being laid at the southern section of the site, between the Luncarty and Stanley junctions. Road users can now see the new northbound carriageway as they travel north of Luncarty.
Once the southern section of the pavement operations are complete, surfacing operations will move to the north of the project to commence forming the new southbound carriageway working south towards Bankfoot.
Culvert extensions and head walls have now been completed including two large culverts at the Shochie and Ordie burns. The drainage adjacent to the carriageway was also progressed ahead of the new road construction which includes connections below the existing road. These connections allow the surface water run-off to flow to the SuDS (Sustainable Drainage Systems) ponds. In addition to the drainage, kerbing for the new carriageway has also commenced and road users will see this in place at the new carriageway north of Luncarty and also at the north end of the site, ahead of the new road being laid.
Earthworks for the project this period focused on embankment construction at the new Stanley/Tullybelton junction. The structures were also backfilled as the construction of the concrete supports and decks progressed.
The Tullybelton overbridge deck is now complete and now that the temporary supports above the carriageway have been removed, the final profile of the bridge deck is now visible to road users.
Good progress was made on two more structures, with the successful installation of precast concrete beams at both Pitlandie and Coltrannie overbridges during full overnight closures of the A9 at the end of November. These two important structures will provide new safer access for residents and farmers who live and work adjacent to the A9. These new accesses will also allow the existing accesses off the A9 to be closed to help improve road safety along this section of the A9. See a timelapse video of the beams being installed.
During the overnight closures works at drainage crossings and general maintenance of the traffic management were also undertaken along with refreshing temporary white lines at junctions throughout the site.
The earthworks stage of the project continued throughout Summer 2019 with the majority of earthworks to the south of the new Stanley/Tullybelton junction nearing completion.
North of the Stanley/Tullybelton junction, earthworks continued with the excavated material from Bankfoot being used as fill material for the construction of the Tullybelton East junction. The earthworks around this structure included the shaping of the approach embankments on either side of the junction which will form the new slip roads to tie into the existing Stanley road. In total, approximately 610,000 m3 of material had been excavated by the end of August 2019, enough to fill 244 Olympic size swimming pools.
The traffic management for the site underwent a change in June 2019 as a temporary mini-roundabout was installed south of Bankfoot. The temporary mini-roundabout helps to manage the safe flow of traffic during construction of the new A9 dual carriageway.
The temporary roundabout allows site vehicles direct access from the A9 to the quarry located at Loak Farm which provides the materials essential for the construction of the project and reduces the volume of construction vehicles on the local road network, which would otherwise need to come from quarries further afield.
Carriageway drainage on the southern end of the project commenced in July which involved laying pipes along the length of the new carriageway. Drainage is a key part of any road network as it allows surface water to run off the new carriageway to designated collection basins, ensuring the safe operation of the road for road users.
Works continued at Shochie and Ordie Burns to extend these culverts to allow for the wider A9 dual carriageway.
The project reached a significant milestone at the end of July following three overnight closures of the A9 to allow the installation of bridge beams to construct the new Stanley/Tullybelton junction. A total of 15 beams weighing 765 tonnes - the equivalent of 60 double decker buses – were installed to form the new structure over the carriageway. During the month of August, work began on the construction of the deck of this structure.
Construction of the concrete columns at Pitlandie, Coltrannie and Gelly overbridges progressed during August.
At Bankfoot North Junction, works to extend Hunters Lodge underpass progressed with the southern abutment cast.
The steep embankment at Broompark was cut to make way for the new dual carriageway. Soil nails were used to stabilise the steepened slope. Soil nailing involves drilling holes into the slope and fixing long steel bars into the holes with grout.
Further north of Bankfoot, site clearance and boundary fencing works continued, with earthworks commencing in the area to prepare for the construction of the two new overbridges at Coltrannie and Gelly.
The traffic management to the south of Luncarty junction was altered at the end of August to allow the first 2.4km of new carriageway to be constructed and tied into the existing dual carriageway. In advance of the new carriageway being constructed, drainage and foundation layers for the road were completed in preparation for the Cement Bound Granular Material (CBGM) being laid on this stretch.
The CBGM material is produced at the onsite batching plant adjacent to the project office at Loak Farm, along with some of the raw materials for the concrete and road pavement.
Since the construction contract was awarded in September 2018, preparatory works including design, and construction works have progressed well during the initial months to June 2019. The project moved into the earthworks phase, where approximately 700,000m3 of earth is expected to be moved during summer 2019 season. That equates to approximately 280 Olympic sized swimming pools! The earthworks form the foundation of what will become the new widened A9.
The design of the dual carriageway has continued to progress, with more than 100 design packages delivered. Design packages are made up of many drawings and specifications which detail how each individual element of the project will be constructed.
To reach this crucial stage, our contractor consulted widely with a range of key stakeholders including Perth and Kinross Council, BEAR Scotland, Scottish Natural Heritage (SNH) and Scottish Environment Protection Agency (SEPA), to ensure that the needs of our stakeholders have been considered and included during design development.
Construction activity increased during the period and road users will have noticed a significant step-up in activity. This included:
- The new Stanley/Tullybelton Junction begun to take shape with hundreds of tonnes of earthworks placed to create the verges on both the east and west sides of the new A9. The overbridge also began to take shape in May, with both abutments formed and column construction underway ready for the pre-cast concrete beams to be lifted into place during overnight closures of the A9 in late July.
- Site clearance and boundary fencing works were nearing completion in all key areas of the site.
- Culvert extensions north of Bankfoot (which allow water to flow under the road) were completed to facilitate the widening of the A9.
- Public utility diversions such as BT cables were also well progressed.
- The temporary Bailey bridges installed earlier in the year crossing the Shochie an Ordie Burns became operational in April 2019. These Bailey bridges enabled our contractor to move tonnes of material to areas where fill is required, without having to use the existing A9. This has dramatically reduced the number of site vehicles using the A9, minimising delays to road users.
- To the north of Bankfoot, soil nailing works commenced on a slope in early May to retain the ground adjacent to a private property.
- At the northern extent of the project, construction also commenced at both Coltrannie and Gelly overbridges.