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@ U S T . H K
Further innovative research in relation
to mitigation of landslides and debris
flows is ongoing at HKUST in the
complementary area of quantitative
multi-risk assessment, an emerging field
in which the University’s geotechnical
engineering researchers are taking
the lead locally and globally. When
landslides and debris flows occur, one
of the biggest risks is that they are not
isolated events. The aftermath and
chain reactions that can follow may
in fact cause the greatest damage. As
an example of the complexities facing
researchers in assessing such hazards,
Prof Limin Zhang cites the real-case
scenario of a building impacted by the
2008 Sichuan earthquake, next by a
landslide behind it, then by flooding
and repeated debris flows. “Previously,
as a civil engineer, vulnerability would
be viewed as different levels of injury to
a person or damage to a building. But
when we face multi-hazards and their
interactions, vulnerability becomes a
very difficult issue,” he said.
Prof Zhang is a global expert on
engineering risk assessment and
QUANTIFYING THE RISKS
OF LANDSLIDES AND
CHAIN REACTIONS
Geotechnical multi-risk
assessment is an emerging
area of focus and we are
among the few institutions
working on the science
PROF LIMIN ZHANG
Professor of Civil and
Environmental Engineering
Research Scheme of the Hong Kong
Research
Grants
Council.
The
project will develop the world’s first
scientifically based design guidelines
for multiple flexible barriers. Flexible
barriers can undergo large deformation,
which is ideal for dissipating high-
impact energy. Advantages of using
multiple flexible barriers include their
constructability, enabling designs to
conform to complex mountainous terrain,
their ability to blend into the natural
surrounding environment, and lower cost.
Facilitating the research is a specially
constructed world-leading 160-meter
long flume facility in Kunming, Mainland
China – part of a collaborative research
effort between HKUST and the Chinese
Academy of Sciences’ Institute of
Mountain Hazards and Environment.
The flume will play a key role in revealing
fundamental mechanisms of interaction
between fast-moving landslides and
multiple flexible barriers. To complement
these large-scale flume tests, the
researchers have developed the world’s
first geotechnical centrifuge model
package which is capable of simulating
flexible barriers for centrifuge testing.
Work in the project’s first year has already
made an impact internationally, with
Prof Ng and his team awarded a Telford
Premium Prize in 2017 from the UK’s
Institution of Civil Engineers and an R.M.
Quigley Award (Honourable Mention) by
the Canadian Geotechnical Society for
their papers on debris flows. The former
prizes are awarded annually to work that
is judged by peers to be of exceptional
quality and benefit to those involved
in civil engineering, construction, and
materials science, while the latter awards
are given to selected papers out of 296
published in the
Canadian Geotechnical
Journal
in 2016.
Prof Ng has published some 250
articles in leading geotechnical journals
and is the first author (with co-author Dr
Bruce Menzies) of
Advanced Unsaturated
Soil Mechanics and Engineering
(CRC
Press 2007). Prof Ng was elected as the
President of the International Society
for Soil Mechanics and Geotechnical
Engineering (ISSMGE) in September
2017, becoming the first in Greater China
to hold this position in the 91 member
societies, over its 80-year history.
Timeline of the multi-hazard scenarios
that affected Beichuan following
the Wenchuan earthquake
Engineering Geology 180, 4-20 (2014)
Timeline of the Multi-hazards Caused by theWenchuan Earthquake in Sichuan
12 MAY 2008
BEFORE EARTHQUAKE
EPISODE 1
Wenchuan earthquake; collapse of buildings
EPISODE 2
Landslides; rock avalanches
BEICHUANTOWN
