The University of Sydney
Master of Engineering (Civil Engineering)
Homework 01: Geotechnical
Incident Report
Professor:
Fernando AlonsoMarroquin
Author:
SID 520303151
An Assignment submitted for the UoS:
CIVL6450 Analysis and Design of Pile Foundations
February 23, 2023
Contents
1 Summary of incident
2
2 Direct and contributory causes
2
3 Analysis of the safe work procedures
3
4 Actions that would have been prevented the incident
4
5 References
5
1
1
Summary of incident
In July 2018, while doing civil works at a site construction in Turkey, an
excavator operator was injured when tons of concrete and soil fell from a
height of approximately fifteen meters from the top and the bottom of a
retaining wall, striking the worker and losing assets, like all the construction
work that the contractor had been developing by that time and the excavator
that was inside the field, which finally caused a loss of life.
2
Direct and contributory causes
The purpose of retaining walls is to support the weight of sloped soil and
buildings, earthquake loads, machine loads that produce vibrations, and
other. (McKelvey, 2011).
Being said that, the primary reason for the failure seems to had occurred in
the next chronological order:
i.
ii.
iii.
The primarily reason for the failure seems to be the height of the wall,
about 15.00 meters.
As a consequence of the lack of draining system in the structure, water
had been accumulating behind the structure due to different reasons,
like water leakage from drinking water systems adjacent to it and/or
heavy rain behind it.
As additional loading is not usually taken into consideration for the
design, the water was developing pressure along the wall surface; so,
as the water didn’t find any way to go out, it started to erosion the
ground at the bottom of the structure.
Presence of
water
Erosion at
the bottom
2
iv.
The failure started at the bottom of the foundation and went up to the
upper section of the structure, so it can be concluded that pore water
pressure appeared to be the trigger of the failure.
3
Analysis of the safe work procedures
A hazard is any factor which can cause loss of life or health, and the sources
in work processes are technical factors (i.e.: machines, devices, materials),
organizational factors, and human factors (e.g., errors made by the worker),
or may be generated by the external environment and other civil structures
situated within or outside the building site. (Bozena, 2011)
Being said that, we can conclude that the hazards were being well identified;
however, as we can see in the picture below, the action that had been done to
control the risk was not well developed because the strut must had been
allocated closest to the resultant force (Fr) of the soil pressure.
3
𝒉
Strut
𝑯
𝑭𝒓
𝑯
𝒉
𝟑
Also, there is no people who alert the workers that an incident has occurred,
which finally allows people to get out from the site work.
Finally, some soil samples could had been taken frequently in order to
analyze the humidity content.
4
Actions that would have been prevented the incident
i.
Making holes in the retaining wall that could had drained the water.
ii.
Taking soil samples could had been taken frequently in order to
analyze the humidity content.
iii.
Analyze the pressure band in the surface of the retaining wall, so that
the strut could had been well allocated.
iv.
The design should had considered end bearing piles in the perimeter
of the land, that must had been done previous to earth works, because
these structures are good for lateral loads and moment loadings.
4
5
References
Bozena, H. (2011). Methodology of hazards identification in construction
work course. Journal of Civil Engineering and Management, 577-585.
McKelvey, J. (2011). Lessons Learned From Failures: The Wall of Shame.
Geo-Frontiers Congress 2011, ASCE, 3235-3234.
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