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Proceedings of the 18
th
International Conference on Soil Mechanics and Geotechnical Engineering, Paris 2013
earthquake, disruptions and distress in an underground transit
system due to terror attack are examples of disasters related to
geotechnical systems. Thus, geotechnical engineering has a
wide gamut and a global reach, and can influence the
sustainable development of infrastructure and civil societies in a
significant way. According to Long et al. (2009), there are seven
categories where geotechnical engineering can contribute to
improve the sustainability of the societal system. These include
(i) waste management, (ii) infrastructure development and
rehabilitation, (iii) construction efficiency and innovation, (iv)
national security, (v) resource discovery and recovery, (vi)
mitigation of natural hazards, and (vii) frontier exploration and
development. A similar set of sustainability objectives for
geotechnical engineering was also identified by Pantelidou et al.
(2012): (i) energy efficiency and carbon reduction, (ii) materials
and waste reduction, (iii) maintaining natural water cycle and
enhancing natural watershed, (iv) climate change adaptation and
resilience, (v) effective land use and management, (vi)
economic viability and whole life cost, and (vii) positive
contribution to society.
Figure 1. The four Es of sustainability in engineering projects (Figure 1
of Basu et al.).
On a project level, Basu et al. outlined the necessary steps to
achieve sustainability objectives as (i) involving all the
stakeholders at the planning stage of the project so that a
consensus is reached on the sustainability goals of the project
(such as reduction in pollution, use of environment friendly
alternative materials, etc.), (ii) reliable and resilient design and
construction that involves minimal financial burden and
inconvenience to all the stakeholders, (iii) minimal use of
resources and energy in planning, design, construction and
maintenance of geotechnical facilities, (iv) use of materials and
methods that cause minimal negative impact on the ecology and
environment, and (v) as much reuse of existing geotechnical
facilities as possible to minimize waste. In addition, emphasis
should be put on proper site characterization so that geologic
uncertainties can be minimized, on instrumentation so that
proper functioning of a geotechnical facility can be ensured and
required retrofitting can be performed, and on adaptive
management strategies so that the resilience of the geotechnical
facility can be enhanced and the vulnerability of the community
linked with the facility can be reduced.
According to Basu et al. and Vaníček et al., sustainability
related studies can be grouped into the following areas: (1) the
use of alternate, environment friendly materials in geotechnical
constructions, and reuse of waste materials, (2) innovative and
energy efficient ground improvement techniques, (3) bio-slope
engineering, (4) efficient use of geosynthetics, (5) sustainable
foundation engineering that includes retrofitting and reuse of
foundations, and foundations for energy extraction, (6) use of
underground space for beneficial purposes including storage of
energy, (7) mining of shallow and deep geothermal energy, (8)
preservation of geodiversity, (9) environmental protection
including protection of greenfields, (10) geohazard mitigation
including mitigation of the effects of global climate change and
multi-hazards, and (11) incorporation of geoethics in practice.
Basu et al. emphasized the need for reliability- and resilience-
based design as a part of sustainable geotechnical engineering.
Additionally, Basu et al. summarized the different sustainability
assessment tools available in geotechnical engineering and
categorized them into (1) single criterion based metrics (e.g.,
carbon footprint), (2) multiple criteria-based tools (e.g.,
GeoSPEAR and life cycle assessment), and (3) point-based
rating systems (e.g., I-LAST and GreenLites).
Based on the above discussion, it is evident that sustainable
geotechnics is an emerging sub-discipline of geotechnical
engineering that covers a wide area ranging from reliability- and
resilience-based design and environment-friendly construction
practices to energy geotechnics and geohazard mitigation. It
also includes the development of sustainability assessment tools
applicable to geotechnical engineering practice.
3 THEMES COVERED IN SUSTAINABILITY SESSION
There are 28 papers allocated to the sustainability session with
authors from 20 countries representing all the ISSMGE regions.
These papers cover a wide range of topics that can be broadly
grouped into five areas.
Class and Property
Conflict
Environment
Economy
Equity
Engineering
Resource and
Pollution Conflict
Growth Control
Conflict
Redundancy and
Profitability Conflict
Access and
Marginalization
Conflict
3.1 Use of recycled and alternate materials
According to Vaníček et al., a variety of waste products are
generated in the society that can be utilized in geotechnical
constructions. These waste products can be categorized into
industrial wastes (e.g., ash and slag), construction and
demolition wastes (e.g., used bricks, concrete, and asphalt),
mining wastes (mine tailings), and other wastes (e.g., tires,
plastics, glass, and dredged material). Basu et al. provided an
overview of the different waste utilization methods in
geotechnical constructions and discussed about chemical soil
treatment. Waste utilization and use of alternative material is
one of the most widely researched areas in geotechnical
engineering and it is not surprising that, out of the 28 papers
allocated to this session, 20 papers contribute to this topic.
The papers on industrial waste recycling deal with a variety
of geotechnical applications. Baykal investigated the use of silt-
sized fly ash in manufacturing artificial, sand-sized pellets for
use in construction projects (Figure 2). He reviewed the cold
bonding pelletization technique, and studied the index and
mechanical properties of the fly-ash pellets. The manufactured
pellets behave like calcareous sands found in the nature.
Figure 2. Manufactured fly ash pellets (Figure 7 of Baykal).
In another example of recycling of fly ash, Vukićević et al.
investigated the reusability of a class-F fly ash (KFA) from a
Serbian thermal power plant as a stabilizer in low plasticity silt
and in high plasticity expansive clay. Several geotechnical
engineering properties including grain size distribution,
Atterberg limits, unconfined compression strength, moisture-
density relationship, swell potential, and California bearing ratio
(CBR) were determined for the control and treated soils. Based
on the study, the authors concluded that the particular fly ash in
question can be used as a stabilizer, and advocated a case-by-
