Sustainability assessment of trenches including the new eco-trench: A multi-criteria decision-making tool
Maria del Mar Casanovas-Rubio
Pablo Pujadas
Francesc Pardo-Bosch
Ana Blanco-Alvarez
Antonio Aguado
2134/9638198.v1
https://repository.lboro.ac.uk/articles/journal_contribution/Sustainability_assessment_of_trenches_including_the_new_eco-trench_A_multi-criteria_decision-making_tool/9638198
<p>Narrow
trenches are a common technique for the installation of utility pipelines of
small diameter. The excavated soil is not always appropriate as landfill and,
in those cases, an appropriate soil from somewhere else (ex. a borrow pit or
another construction site) should be used instead (classical solution, CS).
Another common solution is to use a controlled low-strength (cementitious)
material (CLSM) as backfill instead of compacted soil. However, both solutions
lead to increased raw material consumption, waste generation, need for
transportation, and CO<sub>2</sub> emissions. In an attempt to address these issues,
researchers developed an eco-trench (ECO) that reuses the excavated soil of
narrow trenches to produce a controlled low-strength material to be used as
landfill. Although technically viable, the sustainability of this solution
versus the traditional solution has not been properly addressed. Hence, this
paper aims to develop a method for the sustainability assessment of trenches.
The Sustainability
Index of Trenches (SIT), based on the MIVES decision-making method, enables the assessment and prioritisation of
different types of trenches according to sustainability criteria. Criteria,
indicators, weights and value functions were specifically defined based on
seminars with experts in the field of utility services and construction. A case study was performed in which four types of
trenches (CS, CS with recycling CS+R, CLSM and ECO) were assessed and
prioritised according to SIT. ECO resulted in the most sustainable alternative with
a SIT of 0.80 out of 1 followed by CS+R, CS and CLSM with SITs of 0.63, 0.40
and 0.38 respectively. The
sensitivity analysis showed consistent results in different scenarios. These findings
demonstrate the capability and reliability of SIT as a decision-making tool for
the evaluation of the sustainability of different construction processes for
trenches and the prioritisation of the most suitable solution for different
situations.</p><br>
2019-08-16 09:47:13
Environmental Sciences
Environmental Engineering
Manufacturing Engineering
Trench
Eco-trench
Sustainability assessment
MIVES
multi-criteria decision-making