Crag End landslip, Leeds

12 September, 2017 | 18:30 - 20:30

Venue address:

School of Civil Engineering
University of Leeds
Woodhouse Lane
Leeds LS2 9JT
United Kingdom
Before and after – the 300m section of the B6344 near Rothbury
Before and after – the 300m section of the B6344 near Rothbury

About this event

The Crag End Landslip project comprises the reconstruction of a 300m section of the B6344 near Rothbury for Northumberland County Council. Closed in December 2012 following multiple landslips and failure of an existing retaining wall, triggered by one of the wettest periods on record, the road provides the main link between Rothbury and the principal road network. The slope and River Coquet below the road form a Site of Special Scientific Interest and the land upslope is part of the Cragside Estate owned by the National Trust.

Closure has had a significant socio-economic impact, and as well as being a major inconvenience to residents it affected the main industries in Coquetdale - farming, forestry and tourism. VBA (VolkerStevin Boskalis Atkins joint venture) designed and constructed an anchored bored-piled retaining wall to support the road and an innovative passive dewatering system to reduce groundwater pressure. This robust, low maintenance solution ends decades of instability, leaving an engineering legacy for Rothbury.

The client was keen to reopen the road as soon as possible as residents were faced with a substantial detour to access Rothbury. The local economy depends heavily on tourism which had been badly hit by the road closure. VBA has designed and implemented a solution comprising two main elements – a deep dewatering system to reduce the risk of instability by lowering artesian groundwater pressures, and an anchored bored pile retaining wall to support the road in the event of a slip. The team faced numerous challenges including variable ground conditions, high groundwater and difficult access on a constrained site.

This talk will be split into three parts:

  • Part 1 will give an overview of the project, discussing the geology and hydrogeology, challenges faced during intrusive ground investigations, causes of instability and the landslip mechanism.
  • Part 2 will cover the technically complex bored pile anchored retaining wall design, provide an overview of the chosen passive dewatering system, and discuss the design challenges faced.
  • Part 3 will present an overview of construction work and the results of the first year’s monitoring.

Speakers

Paul Berry (Senior Geotechnical Engineer, Atkins, Newcastle-Upon-Tyne)
Michael Gavins (Chief Geotechnical Engineer, Atkins, Warrington)

Click the ‘speaker’ tab for more about our speakers.

A joint meeting with the Geological Society. Refreshments from 18.00.

Contact

For more information please contact:

Alan Willoner
e: alan.willoner@mottmac.com

Register your attendance

To book your place, simply click the 'book now' button below and follow the onscreen instructions.

If you're not already an ICE member, you can register to receive updates on our latest events.

If you experience any issues, please contact the event administrator: iceyandh@ice.org.uk.

Book now

Disclaimer: Any views or opinions expressed on any matters by the presenters or participants during or in connection with this presentation are solely the views of the authors of the respective comments and/or opinions and must not be taken to be the views of ICE or any other organisation. ICE makes no representations, warranties or assurances concerning any information provided in these presentations and accepts no responsibility for the content and/or accuracy.

Speakers

Paul Berry (Senior Geotechnical Engineer, Atkins, Newcastle-Upon-Tyne)

Paul is a Chartered Geologist with over 12 years' geotechnical experience and manages geotechnical work in Atkins Newcastle office. Paul has experience of the design and analysis of geotechnical structures, including but not limited to; shallow foundations, retaining walls, embankments, cuttings and soil and rock slopes. He also has experience of slope stability analysis, interpretative reporting and detailed geotechnical design for highways construction. Paul supervised the construction works that allowed the B6344 to be re-opened following a major landslip and is currently managing the monitoring phase of the works.

Michael Gavins (Chief Geotechnical Engineer, Atkins, Warrington)

Mick is a Chartered Civil Engineer with 30 years' experience mainly in the geotechnical and structural design of piled foundations, retaining walls, ground anchorages, deep basements, soil nails and slope stabilisation for highway, rail, energy and commercial schemes in the UK and SE Asia. Having worked predominantly for specialist foundation contractors where Mick held the positions of Design Manager and Technical Director, he has also managed multidisciplinary foundation projects and sites in the UK and Asia.

Mick provides technical lead in Atkins ground engineering for foundations and retaining walls on multiple projects. He has been a member of steering committees for British Standard and CIRIA documents and authored chapters of the ICE manual of Geotechnical Engineering and the ICE Specification for Piling and Retaining walls.

Top