Working on behalf of Holcim UK, a Careys team has completed works on a new cement manufacturing and distribution facility at the Port of Tilbury in Essex, southeast England.
A key part of the project involved the use of over 3,500 concrete piles of various dimensions. Playing a critical role were PC400 and MultiBar Large hydraulic pile croppers supplied and supported by National Pile Croppers (NPC).
Holcim UK has recently announced that it has reached a pivotal milestone in the construction of its flagship Tilbury cement terminal, with the successful completion of all civil engineering works. This marks a key point in the multi-million-pound project, as structural and mechanical installation begins on one of the most advanced facilities of its kind in the UK. Located at the Port of Tilbury on the River Thames, the state-of-the-art terminal is central to Holcim UK’s long-term strategy to redefine sustainable construction through innovation, circularity, and decarbonisation.
The three-year construction project has completed all excavation, foundations, buried utilities, and site roads. Every element of the build to date reflects Holcim UK’s and its contractors’ commitment to sustainability. Materials excavated from the site have been reused either in the construction process itself or in Holcim manufacturing plants.
Meanwhile, the civil works have used the firm’s own portfolio of lower-carbon products, including ECOPact ready-mixed concrete, recycled aggregates, concrete paving, and reclaimed asphalt. In total, more than 25,000m3 of concrete from the original site have been reused, alongside 10,000 tonnes of recycled asphalt planings. Additionally, nearly 20,000 tonnes of excavated material have been processed through Holcim’s waste management operations.
Working on behalf of Holcim UK, Careys commenced groundworks in early February 2024, followed by the main civils package. This included concrete works for the storage hall, VRM, silo array, conveyor systems, and other structural foundations. Additionally, it involved the installation of surface water and foul water drainage, utilities, a fire main, and water and gas services, as well as asphalt site roads. Before all this work could be undertaken, there was the small matter of installing over 3,500 concrete piles and subsequently cropping them to size. The concrete piles had various dimensions – 250mm, 300mm, and 350mm– and were driven by Aarsleff. In addition, 400mm precast piles were manufactured by Aarsleff. The latter is highly unusual in the UK, although favoured in the US.
As Careys’ pile cropper partner of choice, NPC supplied the hydraulic pile croppers and support for the project over some months. Given the importance of the facility to Holcim UK, both Careys and NPC were fully committed to being environmentally focused, with the concrete and rebar from the piles being reused and recycled. Additionally, the project’s time frames were demanding, with little room for unscheduled downtime. Safety, efficiency and productivity had to go hand in hand to ensure that Careys’ part was completed on time, to the exacting standards specified.
NPC’s MultiBar Large is designed to aid in such projects, proving to be the workhorse of the cropping onsite. It is lowered over the concrete pile, which is then reduced at 250mm intervals, enabling broken pile sections to be removed. The key to productive and efficient use is to ensure that the last bite at the finish level is of at least 250mm to ensure a good cut is obtained.
“The cropper is best used by an excavator of at least 6t, and depending on the variant chosen, it weighs either 450kg, 550kg or 600kg. This all means that it’s small enough to be highly manoeuvrable but has the substance to deal with the toughest of precast piles with four or more reinforcement bars (rebar),” explains NPC’s Roy Taylor.
Further aiding efficiency and crop refinement, the MultiBar Large benefits from a new range of specifically in-house manufactured chisels, designed to not only penetrate the pile but also leave a perfect finish with minimal tidying up required. The new chisels effectively break up the concrete into pieces, and the cropped unit can then be easily lifted off the pile, enabling the safe removal and recycling of the cut-away concrete.
One highlight of the project was the use of NPC’s newly designed cropper for piles ranging from 300 to 400mm. As its name suggests, the PC400 is used for precast piles with four or more reinforcement bars. The new cropper is designed for flexible and efficient use, weighing in at only 550kg, and can be mounted on a 6-tonne excavator. The cropper is designed to remove sections of concrete at approximately 250mm per crop, utilising four powerful rams and blades that penetrate past the rebar and into the centre of the pile, resulting in minimal trimming.
“The PC400 proved itself on this project. Careys reported high levels of productivity and ease of use,” added Roy, who concludes. “Being able to be used by a 6-tonne excavator meant that cropping could be undertaken with existing equipment on-site. The cropping was undertaken in a timely and efficient manner, with the concrete and rebar being able to be recycled and reused in line with Holcim UK’s inspiring environmental goals.”
