Civil engineering

We are a leading contractor for the design and construction of new highways and maintenance schemes. Our ECI (early contractor involvement) successes include:

• A5 Weeford to Fazeley improvements
• A1 Peterborough to Blyth grade-separated junction
• A38 Dobwalls bypass
• A30 Merrymeet junction
• Avon Bridge replacement

Our considerable experience in major maintenance of both highways and structures encompasses both stand-alone and framework contracts. Our knowledge of the statutory processes enables us to play a key role in supporting Public Inquiries, both in their preparation and with our own staff acting as expert witnesses.

We have specialist in-house capabilities in traffic management and are accredited for National Highways Sectors 12A, 12B & 12D (Local Authorities roads).

Highways micrositeOur dedicated Highways microsite brings together all our higways engineering skills in one place.

Design excellence is an essential part of successful project delivery. Interserve offers design services both through in-house resources and in partnership with some of the UK’s leading design consultants.

All our services are accredited to ISO 9001:2000. These cover design, construction, project and facilities management and associated services that include National Highways Sector Schemes 12A, 12B and 12D for traffic management.

We advocate being involved as early as possible in our clients’ projects, ideally from the initial project scoping and feasibility. This allows Interserve to input into how the project will take shape and add our experience in buildability, in-house technical expertise, experience from other similar schemes, knowledge of how much construction costs and our knowledge of the potential implications of planning constraints.

Contributing at the early stages of a project avoids unnecessary duplication of effort and offers greatest potential to add value. Integrated teamworking with the client, consultant, cost-consultant, key subcontractors and suppliers is a tremendous by-product of this early involvement. Examples of where clients have benefited from this include:

• A38 Dobwalls bypass: budgetary savings for the rail overbridge
• A1 grade-separated junction: innovative design of bridge decks
• A12 Stanway: pullout tests to prove new lighting column fixing arrangement on slip-formed concrete barrier

We have extensive experience of working in environmentally-sensitive locations, where archaeological investigations are sometimes needed, and sustainable approaches are essential.

• Through our Site Services we can offer complete site set-up services for accommodation and welfare, connection of all utilities, and the servicing of the facilities.
• We offer solar powered welfare units, bio-digesters for sewage treatment in remote locations, and general construction waste recycling.
• We can also provide site security, cleaning and catering and are used to dealing with the utility companies, managing the arrangements for the new works and related service location and/or diversion.
• Our services include off-line (on-site) pre-casting of structural elements and offsite pre-casting and the fabrication of structural steelwork. This can give critical-path savings in time - and cost. We are highly experienced in the transportation of heavy structural elements into their final positions on site.
• Our Technical Services team provides advice, design and checking services for temporary works issues at tender, construction and post-construction phases.
• We can offer total access solutions via tidal routes, as for our Westminster Bridge fascias replacement contract, thereby avoiding disruption to the traveling public.
• We are expert in the encapsulation of structures prior to hydro-demolition or shot blasting, where the protection and contamination-prevention of what lies below is essential.

We offer ground stabilisation techniques that cover a wide range of civil engineering solutions, including:

• Piling - timber, steel sheet, tubular, H-section, bored, CFA, screwfast
• Retaining walls – precast concrete, in-situ concrete, steel, gabions, geotextile
• Slope stability, including ground anchorages and soil nails
• Ground-water control, including de-watering and well points
• Foundations and underpinning
• Drilling and grouting, lime stabilisation

Interserve is accredited to the Register of Qualified Steelwork Contractors Scheme for:

• RF bridge refurbishment steelwork, contract value above £6 million
• PT Plate Girders (>900 deep), trusswork (>20m long), steelwork
• BA stiffened complex platework in decks, box girders, arch boxes
• MB moving bridges steelwork

We have carried out major refurbishment works to numerous motorway and railway structures, the majority under demanding technical and logistical constraints. Our structural repair capabilities include:

• Weld procedure development
• Control and application of heat and pre-heat into structural elements
• Avoidance of buckling through physical restraint of slender elements
• Prevention of unequal or uncontrolled load transfer
• Perfecting methods of cutting structural steelwork in confined spaces without risk to parent materials
• Methods of maintaining tolerance on fitted members
• Erection of steelwork to detailed matrix layouts in Box Girders

We have worked country-wide on the network of major arterial roads and motorways for key clients such as the Highways Agency, developing our skills through innovation and experience in:

• Concrete repairs (deck end, mid-span and deck edge)
• Parapet, cross beam and column removal, refurbishment and replacement
• Temporary works - design/installation of access scaffold to heavy duty support steelwork
• Jacking of whole motorways, bearing remedials and replacements
• Hydro-demolition and welding reinforcement
• Development and trials with suppliers of repair products
• Implementation of structural monitoring
• Cathodic protection (including discrete anodes) and silane treatment
• Establishing on-site, NAMAS-accredited (National Accreditation of Measurement and Sampling) concrete-testing facilities

• Over 60 years' experience of working in marine environments
• Proven procedures relating to all aspects of safety, quality and environmental management
• Extensive experience working on the tidal River Thames
• Our own marine construction plant, including:
  • 30m x 18m crane barge
  • 12m x 18m jack-up barge
  • 5m x 2m small rib boat
  • 7m x 2.5m diesel work boat
  • Sixteen 5m x 2.5m unifloat pontoons + 4 swim ends
• Development, installation and removal of substantial temporary works

See also the section on our capabilities in the marine/rivers sector.

We have experience of working on nuclear, coal, CCGT (combined cycle gas turbine) and energy-from-waste (EfW) power stations and have successfully completed a variety of design and construct projects for building, infrastructure and maintenance works, including:

• Contractors' compound facilities
• Low- and intermediate-level waste facilities
• 400/275/132 KV substations
• Major energy-from-waste reinforced concrete structures, combined heat-and-power (CHP) plant
• Sizewell B substation and A maintenance
• British Energy maintenance - 5 sites
• Access roads, storm drainage and infrastructure
• Control security buildings
• Testing facilities

We can also offer a wide range of mechanical and electrical, pipework fabrication and building services as well as site security, welfare, catering and cleaning.

See also the section on our capabilities in the energy and utilities sector.

We deliver all types of steel and concrete piled solutions via our in-house resources and with our supply chain partners.

Steel piling comprises the majority of work delivered in-house, with our team accredited to provide design support for both temporary and permanent works solutions. We can design, install and remove (if temporary) the following types of steel piles:

• Sheet
• Universal bearing and column
• Tubular and casings to cofferdams
• Bases and foundations in most locations and geotechnical situations prevailing in the UK

We have plant and equipment to install these on land and over water - a good example being the London Eye foundations, with associated temporary works in the River Thames. We offer a wide range of piles including rotary bored, continuous flight auger, contiguous and secant wall, driven precast and tripod rig bored.