Earth Friendly Concrete Trials Tunnel Linings

Completed

Other Cross-Cutting Technologies or Research
Other Power and Storage Technologies(Electricity transmission and distribution)

Applied Research and Development

ENGINEERING AND TECHNOLOGY (Electrical and Electronic Engineering)
ENGINEERING AND TECHNOLOGY (Civil Engineering)

Not Cross-cutting

Project Contact
National Grid Electricity Transmission

Network Innovation Allowance

Ofgem

01 January 2025

30 April 2025

ENA months

£159,174

Power

London

Network Innovation Allowance

Project Contact, National Grid Electricity Transmission

Earth-Friendly Concrete (EFC) is a groundbreaking, cement-free material that offers a significant reduction in carbon emissions, with performance comparable to standard concretes, aligning with the construction industrys urgent drive to reduce its carbon footprint.EFC is compliant with BSI PAS 350 Flex and presents a critical opportunity for National Grid to lead in innovation while advancing its net zero goals.National Grid Electricity Transmission (NGET) has partnered with HOCHTIEF-MURPHY Joint Venture (HMJV) to conduct the study. Wagners Earth Friendly Concrete (EFC) has been employed in construction projects in Australia over the past 12 years, garnering numerous awards and accolades for sustainability and innovation. Its geopolymer binder has no traditional Portland cement; instead, an alkali activator chemically reacts under ambient curing conditions with two well-known industrial waste by-products GGBS (waste from iron production) and Fly Ash (waste from coal-fired power stations). Both materials have been used as supplementary cementitious materials (SCMs) in concrete production for decades. Tunnels are essential infrastructure that provide mass transportation, hydroelectric power plants, sewerage, potable water supply and other utilities that can improve quality of life, the economy, public health, and the environment.Tunnels can, at a network and system level, reduce CO2e emissions. For example, by providing fast and efficient train or metro services, car use can be reduced. Or, by providing a shorter, flatter route, a tunnel through a mountain can reduce journey times, energy consumption and air pollution. Compared to other potential solutions, e.g. a bridge or surface option, tunnels are often more resilient and durable, require less maintenance, and have less impact on the environment.Most tunnels are constructed with concrete tunnel linings. Other lining types, such as timber, steel or cast iron, are only used in special cases and represent a tiny proportion of the total length of tunnels in the world. Therefore, the easiest way to have the biggest impact is to reduce the CO2e emissions associated with the concrete tunnel linings, and this is the focus of this project.The project will provide guidance on how to reduce CO2e emissions for all types of concrete tunnel linings, including: precast concrete segmental linings, cast-in-place concrete.Trialling of the C50/60 mix in accordance with EC2 and BSI standards will be carried out with the expectancy that the mix will comply with the following:Fresh Concrete- BS EN 12350:2019Slump Testing and Slump Retention BS EN 12350-2Fresh Density BS EN 12350-6Bleed Testing ASTM C232-14Hardened Testing- BS EN 12390:2019Compressive Strength BS EN 12390-3Density (saturated/oven dry) BS EN 12390-7Flexural Strength BS EN 12390-5Tensile Splitting BS EN 12390-6Total Shrinkage ASTM C157Hot Box Temperature Rise/Coefficient of Thermal Expansion/Temperature DifferentialFire Testing ISO 384:1:1999ISO384 CurveFinal report will be published with all the learning outcomes and will be shared with all the licensees. A dissemination event will present all the results to relevant stakeholders with the recommendations of certain technologies ready to use in business as usual (BAU). The work will be delivered in discrete stages each with a focus on different objectives linked to the overall aim to explore concrete tunnel lining segment. This project is planned to take 4 months with the following major objectives:To develop an understanding of the EFC tunnel lining segment technology to allow for identification of usage cases, potential benefits, and readiness for construction trials.To review the technology and summarise the current state of knowledge, trends, challenges, and opportunities in utilising EFC as alternatives in Tunnel lining segments.To review the current design codes and approaches to explore how they might be applied in the design of polymer concrete structures.Final recommendations to identify the potential benefits and implementation learning outcome.

n alignment with National Grid Electricity Transmissions (NGETs) objectives of achieving net-zero construction, we aim to evaluate the suitability of polymer concretes as a sustainable alternative to traditional concrete for NGETs construction operations, appraise their readiness for construction trials, and support NGET in undertaking some of the required trials to demonstrate these materials suitability. Earth Friendly Concrete (EFC) has been utilised on the LPT2 (London Power Tunnels 2) project in several areas, but mainly for bulk fill or in temporary works. To further this concrete technology and use EFC more extensively, HMJV in conjunction with its Supply Chain Partners will conduct trials to establish the potential for use in Precast Segmental Lining Elements for the benefit of future projects as part of the LPT legacy.

02/04/25