Report

Teaser, summary, work performed and final results

Periodic Reporting for period 1 - TERRE (Training Engineers and Researchers to Rethink geotechnical Engineering for a low carbon future)

Teaser

The construction sector is one of the main sectors responsible for carbon emissions and accounts for 10% of the carbon footprint globally. This sector will play an important role in the EU\'s long term objective of reducing greenhouse gas emissions by 80-95% by 2050. Energy and...

Summary

The construction sector is one of the main sectors responsible for carbon emissions and accounts for 10% of the carbon footprint globally. This sector will play an important role in the EU\'s long term objective of reducing greenhouse gas emissions by 80-95% by 2050. Energy and environmental issues are increasingly becoming key factors in market competition. As a result, technological innovation aimed at reducing carbon emissions can be viewed as a major strategy to boost competitiveness of the European construction industry, within and outside Europe. This is the rationale behind the project TERRE, which aims to train a new generation of engineers and scientists in carbon efficient design of civil infrastructure.

TERRE targets the geotechnical construction industry, a major component of the overall construction sector, which is strategically important in infrastructure development (transportation, flood and landslide protection, building foundations, waste disposal). This project explores novel design concepts for low-carbon geotechnical infrastructure through 15 PhD projects carried out by ESRs who will be ‘trained through Research’ in low-carbon design. Design concepts include eco-reinforced geomaterials, binders ‘recycled’ from waste, ‘engineered’ vegetated and bare interfaces, shallow geothermal energy, and shallow soil carbon sequestration.

Each individual PhD research project is oriented towards a potential technological application in its later stage by involving industrial full and associated partners. This synergy between industry and academia will ensure that the research remains problem-driven and that the fundamental research has a tangible social, environmental, and economic impact.

TERRE recognises that fundamental concepts concerning greenhouse gas emissions, carbon sequestration and, more generally, sustainable development are often not addressed in higher education in civil engineering. TERRE addresses this knowledge gap by organizing annual Schools, mainly designed for early-stage researchers but expected to be of equal benefit to established researchers and practitioners in the civil engineering field, to help rethink civil engineering design.

Work performed

The TERRE project is structured in four Work Packages, which address different aspects of low-carbon design in geotechnical engineering.

NOVEL MATERIALS FOR CARBON-EFFICIENT GEOSTRUCTURES
a) Feasibility study to investigate the use of alkaline-activated fly ash as binder for soil stabilisation has been completed successfully.
b) Field scale experiments have been designed to investigate the use of timber sheet pile walls in combination with riparian vegetation to stabilise river and canal banks.
c) Preliminary tests to investigate the feasibility of bio cementation to stabilise earthen construction materials (using biopolymers and enzyme-induced calcite precipitation) have been completed successfully.

DEVISING INTERFACES FOR CARBON-EFFICIENT GEOSTRUCTURES
d) Two field trials in Italy and Spain have been set up to investigate vegetation effects on natural and man-made slopes respectively. In addition, a new techniques to monitor xylem water potential (as an indicator of the efficiency of evapotranspiration in generating suction) has been developed
e) A mock-up scale laboratory experiment has been designed and constructed to investigate the use of engineered soil-atmosphere ‘sandwiched’ physical interfaces to generate suction in the ground.
f) A study has been completed on the role of environmental factors (i.e. temperature and soil moisture) on growth of fungal mycelia (to protect riverbanks and flood embankments from erosion). A tensile test for determining shear characteristics of soils strengthened by fungal mycelia has been developed.

GEOSTRUCTURES FOR ENERGY/CARBON CAPTURE AND STORAGE
g) Design criteria for shallow geothermal structures have been developed based on the analysis of the case study of a metro tunnel with station with walls and raft are equipped with geothermal pipes.
h) Mock-up scale experiments to investigate different Carbon input in soils (depending on different plant species used in earth embankments) have been developed. Data on the relationship between root dynamics and Carbon stored in different fractions of soil have been obtained.

OPERATIONAL AND DESIGN TOOLS
i) Criteria for Life Cycle analysis to assess economic and environmental impact have been defined for suction-reinforced geo-structures.
j) An optimisation algorithm was developed to be implemented in ultimate limit state design software for minimum energy/carbon.

Final results

PROGRESS BEYOND THE STATE OF THE ART
The construction sector has been investing significantly in research to produce innovative low-carbon technologies, including low carbon concrete, low carbon steel, and energy building efficiency. However, there has been little innovation in the geo-infrastructure field, which is lagging behind other sectors of the construction industry. TERRE aims at closing this gap by creating a multi-disciplinary and inter-sectoral network to impact the way of thinking of geotechnical engineers. This network is unique in the area of geo-infrastructure and will be complementary to several other networks funded by the European Commission under FP7 on low-carbon infrastructure.

EXPECTED RESULTS UNTIL THE END OF THE PROJECT
- Methods for low-impact stabilisation of geo-materials based on alkaline activation of fly ash (for efficient use of marginal soils)
- Methods for designing bio-based soil reinforcement to stabilise man-made slopes (without the use of concrete or steel)
- Methods for manufacturing bio-based earthen construction materials (stabilised using bio-polymers or enzyme-induced calcite precipitation)
- Methods for stabilising geo-infrastructure using engineered bio-interfaces (including plants and fungal mycelia)
- Criteria to design engineered soil-atmosphere sandwiched interfaces for ‘climate enhanced’ geo-infrastructure
- Criteria for the design of geothermal energy exchanger embedded into conventional shallow geotechnical structures
- Methods for enhancing carbon sequestration and storage by vegetation in new earthfills
- Procedures for carbon footprint assessment of geotechnical construction
- Software for ultimate limit state design of geo-infrastructure incorporating optimisation tool for minimum energy/carbon

POTENTIAL IMPACTS
There is still a gap between research and practice in low-carbon design, particularly in civil engineering. By the end of the project, all recruited researchers will have received excellent training at the interface between Industry and Academia. Collaboration between industrial and academic partners is embedded within the project through the mechanism of ‘Industrial’ PhDs and, for the ESRs involved in ‘Joint-award’ PhDs, through the programme of secondments to industrial partner organisations. It is therefore expected that the ESRs will be able to secure jobs where the interplay between Academia and Industry is the key focus.
TERRE aims to create a permanent school on ‘Low carbon design of geo-infrastructure’, driven by the ESRs recruited by the project. The ESR would be expected to administer the School scientifically and financially with the additional option of delivering CPD courses at individual professional institutions in Europe.

Website & more info

More info: http://www.terre-etn.com/.