BAM Ritchies

De-risking Decarbonisation Delivery

All rail enhancements, renewals and investment projects rely upon the ground to respond in a certain way when loads are applied by the ground engineering solution chosen

To ensure the expected performance of the ground there is a need to gather information and data of the ground that will be relied upon. This capture of information and data is undertaken through the completion of Ground Investigation (GI) projects. The SMARTer the ground investigation the better the results and the more risk is reduced in delivery of the project in the future.

BAM Ritchies is focused on the UK’s Net Zero journey and is delivering on its vision of Building a Sustainable tomorrow. BAM actively engages and delivers services in the renewable energy sector and it believes that delivery of an electrical railway is paramount to a Net Zero future. Supporting new sustainable infrastructure will unlock opportunity and support growth in the economy.

BAM Ritchies was engaged to deliver this project which is for the Ground Investigation requirements for the potential improvements and decarbonisation of the Scottish Rail Network. It covers both the route wide Overhead Electrification Lines GI and the structures GI. Two-thirds of the Highland Main Line is single track and is not electrified – limiting capacity, slowing journey times and undermining reliability. Rail journey times to Inverness are longer when compared to road.

Challenges to delivery

There were three challenges to the delivery: • Large scale. • Difficult conditions. • Broad requirements.

Scale

The scale of the project required up to twelve drilling crews and five additional support labour operatives split between dayshift (offtrack) and nightshift (on-track) works. They needed to work in conjunction with one another for six-month period. Nightshift working on six day working pattern Saturday to Thursday with dayshift working twelve days on and two days off working pattern.

Conditions

Difficult, sloping, soft and boggy ground conditions, river crossings, road closures needed for mobilisations and borehole set ups at various locations. Logistics, engagement and control was key to project success

Requirements

The provided scope of works and break down of requirements was very generic. Generally, ten or eleven-metre borehole consisting of five to six-metre soils and five to six-metre core. Given the site was over 120 miles long, there was limited work done in adjusting the scope to take into account existing BGS information. This presented a challenge when programming the boreholes and the requirement / duration for traffic management for access and egress from locations.

The Collaborative Solutions

Review of scope and requirements of design undertaken in conjunction with BAM Nuttall and Network Rail, led to an alternative approach for sampling of the superficial materials. All cable percussion elements of the works were altered to resonance (sonic) drilling with the resonance drilling machine or dynamic sampling with the rotary drilling machine removing the requirement for two of the twelve drilling crews. The programme of dayshift works was not on the critical path and therefore the duration was increased with further reduction of another two of the twelve drilling crews. In total only nine drilling crews were required for the works.

Review of scope and requirement of design undertaken in conjunction with BAM Nuttall and Network Rail lead to a descope of various borehole locations resulting in

a cost saving. Due to the general purpose of the work, locations which were deemed difficult with additional measures required to undertake were descoped and noted for potential inclusion within the construction phase of works if further data was required.

Daily and weekly communications between the BAM team and the TM subcontractor allowed for compliance with the programme. In hindsight and through lessons learnt more focus should have been given to overall TM requirements.

To combat fatigue management of the nightshift crews, any possessions which were cancelled due to rail issues were utilised as paid down days for the delivery team.

Commercial Excellence

Close collaboration between the BAM team and the Network Rail team with regards to managing change via digital applications, CEMAR. One of the first rail projects in Scotland to fully embrace CEMAR and the project is now being used as an exemplar to other projects in NR Scotland to manage change through to instructions using CEMAR.

Overcoming Hurdles

Not all access points were known or available to the project team due to various reasons. The delivery team therefore had to adapt new strategies throughout the 120 mile works to deliver the works. This included adding additional resource to the drilling teams so they could share manual handling issues regarding pushing trollies to reach locations on track which would otherwise not be able to reach without RRVs.

Public Support

Overall the liaison between BAM team and the NR Comms team was exceptional, it has been heavily praised with very few concerns raised throughout the works. Thirteen thousand newsletters were issued over the course of the project. On occasions the BAM team structured the delivery of works to minimise impact to residents who

claimed they were high risk to stress events such as these works. So they adjusted works timings and brought these residents along to such an extent that NR were praised by the residents and NR then internally shared the good practice

Innovative Investigations

The supply chain partner, Zetica was on site undertaking Continuous Wave Surface Tests to assist in determining the depth of bedrock. Approximately 50 locations were scheduled and planned over four phases of works due to location and possession planning.

Following the first two phases of works and assessment of results, Zetica and BAM collaborated to alter the methodology due to ambiguous test results. The following two phases were undertaken using Multichannel Analysis of Surface Wave Tests. This allowed for greater details and determination of bedrock.

Overall this project has stretched the capacity of the Scottish GI Team, but by collaborating, challenging and managing BAM was able to optimise the scope, which reduced cost, reduced programme, matched

the resource and maximised the investment in this fundamental exercise to create the ground data for the railways journey to Net Zero.

BAM Ritchies delivering the East Kilbride Electrification project, another aspect of Scotland’s Railway’s strategy to decarbonise rail.

Environmental Focus

Close collaboration between BAM team / NR and the environmental contractor (EC) The railway goes through one of the most ecologically sensitive locations in Scotland and so close collaboration of the three parties was critical to a successful delivery of this project

Engagement included weekly meetings, forward planning on a weekly basis with EC and they in turn carried out surveys etc (both desktop and site via ECoW) to ensure there were no issues. BAM quickly understood the sensitivity of the ecological constraints along the route, to such an extent that the team were pointing things out to the ECoW such as a newt close to one of the BH locations and a nesting bird found to the rear of the site compound.

Company profile

BAM Ritchies is the specialist geotechnical division of BAM Nuttall Ltd. BAM Ritchies started business in Scotland almost 60 years ago in 1963 and is now one of the country’s leading and award-winning geotechnical contractors. The organisation employs approximately 300 trained and experienced staff.

BAM Ritchies has a turnover of over £60 million carrying out ground investigation, ground engineering, drilling and blasting

and concrete techniques: completing contracts up to £30 million in value.

BAM Ritchies operates UK wide from offices in Kilsyth near Glasgow (Principal Office), Warrington, Nailsea near Bristol, and Godstone in Surrey.

Tel: 07740 771075 Email: matt.ewing@bam.com Visit: www.bamritchies.co.uk LinkedIn: BAM Ritchies Twitter: @BAMRitchies