Articles & Researchs
22
An Insight Into Tunnel Failures:
Prominent Causes,Mitigation
Factors And Risk Engineering
Contribution
Thomas Konstantis
Civ. Eng, MSc, Marsh, London, UK,
Thomas.Konstantis@marsh.com
Abstract
progress and integrity, with explicit
these failures along with their
Underground
activities
are
reference on the irreplaceable
distinct characteristics and hazard
always related to a significant
contribution of risk engineering.
sources are discussed. The work
number of risks with variable
carried out by Konstantis, T,
characteristics. The situation can
INTRODUCTION
Konstantis, S and Spyridis, P, 2016
be further exacerbated due to
Underground works and structures
(hereunder referred to as [5]),
numerous relevant parameters
have always been a challenging
forms the basis of this contribution.
such as locality of the works, their
and complex endeavor for all
Onthebasisofthecountermeasures
size, the adopted construction
stakeholders, primarily for the
to be taken, the key factors related
methodology, the existing ground
contractors
and
the
design
to a successful project are quoted,
condition and others. All these
consultants. This is due to the
with clear explanation of their
factors impart significant hazards
various uncertainties that pertain
importance and added value.
with the potential to worsen the
to these projects and their distinct
The invaluable contribution of risk
project's risk profile by increasing
characteristics. In numerous cases,
engineering with the participation
the likelihood of a failure and/or
failure incidents occur which can
of an experienced risk engineer
by magnifying the impact severity.
have significant impact both in
is also discussed in the context
In case a failure scenario is
monetary and time delay terms.
of a pro-active and targeted
realized, the project could sustain
Due to the increased needs and
approach and its consequential
significant physical loss or damage,
requirements
for
infrastructure
benefits.
be unacceptably delayed and
projects, primarily in major urban
The importance and benefits
have
unprecedented
impact
areas subject to their increased
of proactive risk engineering
on nearby third party properties
number
of
inhabitants,
the
management
as
relates
to
and infrastructure. In turn, that
tunneling industry is constantly
the tunnel failures and the
affects all stakeholders among
facing new challenges and is
consequences to the insurance
which are insurers who hold a
prone to additional risk exposures.
industry have been qualitatively
substantial portion of the overall
Various reasons, mainly pertinent
outlined by (Konstantis, Konstantis
risks. Available public information
to contractual requirements and
and Spyridis, 2016).
of occurred tunnel failures reveals
restrictions, schedule tightness and
damage cost more than USD
project funding, impart increased
TUNNEL FAILURES
400m and delays exceeding
pressure to the industry and all
As already mentioned, many
even
4
years.
Hence,
the
the main stakeholders. In turn, this
failure events have taken place
obvious necessity for a profound
could blunt the risk perception
over the last decades. These
examination of all project stages,
and impair risk awareness and
events vary as regards to their
from development until hand over,
vigilance, paving the way for
extent and their severity and all
is undoubtedly emerging. This
unwanted failure events with
manifest a diverse range of
contribution provides an insight
detrimental
consequences.
impact to the stakeholders. A very
into the most prominent tunnel
In this contribution, effort was put
comprehensive list of significant
failure causes and their derivatives
initially on identifying the most
and noticeable tunnel failures
and elaborates on factors that
prominent causes of the tunnel
over the past 50 years can be
play a decisive role in the project's
failures. Some key elements of
found CEDD, 2005, Reiner, 2011,

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