8/12/2019 WRAP_Case Study_Aggregates _The Channel Tunnel Rail Link

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8/12/2019 WRAP_Case Study_Aggregates _The Channel Tunnel Rail Link

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Contract 103: Kings Cross Railway LandsThe contractors identified that large quantities of recyclable materialwas available on a neighbouring contract, which could be recycled asunbound material in the massive earth works taking place at C103.

While cost effectiveness and availability where important factors in thedecision to use these recycled materials, the deciding factor was that theuse of these materials avoided approximately 8,000 vehicle movements inCentral London.

Cost effectivenessUse of recycled Use of comparable primary Total Quantity Totalaggregate aggregate saving used saved

Aggregate cost: Aggregate cost:0 8 per tonne

Crushing and (including Aggregates 7 per 130,000 910,000handling: Levy at 1.60 per tonne) tonne tonnes3 per tonne

Total cost: Total cost:3 per tonne 10 per tonne

Contract 310: West Thames Ripple Lane to ThurrockA total of 144,606 m 3 of reject lightweight concrete blocks were used as atemporary and permanent engineering fill. The decision to use thesematerials was made because of their cost effectiveness and local availability.

The blocks were also seen to have a number of distinct performanceadvantages when compared to the alternative low grade primary aggregates. The blocks allowed lighter structures to be built, had better weight resistance, reduced settlement and maintenance and excellent

compressive strength and interlocking.Cost effectivenessUse of recycled Use of comparable primary Total Quantity Totalaggregate aggregate saving used saved

Aggregate cost: Aggregate cost:7.37 per m 3 18.70 per m 3

(including (including Aggregates 9.81 144,606 1,417,904crushing, Levy at 1.60 per tonne, per m 3 m 3

handling and and crushing,handlingtransportation and transportation costs)costs)

Landfill tax: 2 per tonne

Further informationWRAP. The Old Academy, 21 Horse Fair,Banbury OX16 0AH

www.aggregain.org.ukHelpline 0800 100 2040

Please quote reference number 20AGGDisclaimer: While steps have been taken to ensure its accuracy, WRAP cannot accept responsibility or be heldliable for any loss or damage out of or in connection with this information being inaccurate, incomplete or misleading. The listing or featuring of a particular product or company does not constitute an endorsement by WRAP and WRAP cannot guarantee the performance of individual products or materials. For more detail,please refer to our Terms and Conditions on our website www.wrap.org.uk

Printed on recycled paper containing at least 75% post consumer waste and 25% mill broke fibres usingwaterless offset and vegetable based inks.

Lessons LearntOverall, the main lesson learnt from the useof RSA on the various CTRL contracts werethat it was economical, sustainable and

technically feasible. Close liaison andforward planning between the client andcontractors was very important to theeffective use of RSA.

Details of RSA use

Contract Recycled material used Applications Quantity Used

C103 C&D wastes from contract C105 Type 1A, 6N and 6N1 for unbound 130,000 tonnesand fill applications

C&D wastes from a viaduct situated on Granular material, Type 1Acontract C103

Concrete rejected for construction from Unbound and fil l applicationscontract C105 and nearby batching plants

Second hand rail ballasts (about 6 month old) Bedding for large water pipes and fortemporary railways sidings

C310 Reject lightweight concrete building blocks Construction of the piled slab. 144,606 m 3

C440 Spent foundry sand Structural fill around structures 30,000 tonnes

Contract 440: Ashford to CheritonOver 30,000 tonnes of locally sourced spent foundrysand were used on this contract as fill aroundstructures, providing an alternative to low-gradeprimary aggregate.

The use of spent foundry sand was seen to have anumber of performance advantages over primary

aggregates as well as providing both economic andenvironmental benefits

Cost effectivenessThe use of spent foundry sand provided direct costsavings in terms of the reduced material costs. Inaddition, due to the availability of a local supply,transport costs were also significantly lower than for equivalent primary material.

Photograph courtesy of CTRL/Urban Exposure

Date of case study: March 2004