Newport Docks, Collapse of Fully Timbered Deep … · Newport Docks, Collapse of Fully Timbered...
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Newport Docks, Collapse of Fully Timbered Deep Excavation Canary Wharf Tower Crane Collapse Project Overview
At approximately 5.20pm, the timbers supporting the west wall of the
excavation trench collapsed, driving the timber up and together, caus-
ing the walls of the trench to collapse. 46 men were trapped in the
collapse, 39 of whom died due to the collapse or from injury in the
subsequent days. Messrs. Easton Gibb and Son, the contractor em-
ployed by the Alexandra Docks and Railway Company, had been
tasked with extending the already existing Newport dock, for the sec-
ond time in less than a decade. The contractor excavated several
trenches to create a south lock.
The structural failure of the trench occurred during a shift change,
which made it challenging to ascertain how many men were in the
trench, as the record keeping at the time was poor. The inquest car-
ried out by W. W. Squire it was noted that the Timbers were checked
daily by an Messrs. Easton Gibb and Son Engineer (Squire, 1909), .
Also, the walking ganger (The foreman in today’s terms), Ratcliff
was tasked with making sure any problems on site were addressed
and rectified to maintain safe conditions. On the day of the disaster
movement of the piles was not reported by Ratcliff to his superiors,
which shows he was confident in his abilities.
Key Project Facts
Date: 2nd of July 1909, 5.20pm
Contractor: Messrs. Easton Gibb and Son
Client: Alexandra docks and Railway company
Structure: 14” timber walled trench between
56 and 44 feet deep and 238 feet long
Function: Dock wall foundations
Fatalities: 39 men
Economic Social Environmental
The dramatic increase in Coal export re-
sulted in the expansion of the area of the
dock, the South Quay. In 1909, Newport
was a thriving merchant town. With a
brand new Transporter Bridge, designed
to allow access to sailing ships on their
way to the docks. The wealth increase in
import and trade suggested the people
were more driven to expand the docks,
arguably this lessened their attention to
detail in design and implementation. Re-
ports show this where part of the east
trench timbering drawings was increased
from 6 to 14 inch, also done in the west
trench, further stating it seemed evident
that it was necessary to take more than
In 1882, Alexandra (Newport) Dock
Company was renamed the Alexandra
(Newport and South Wales) Docks and
Railway (ANDR). Following this, the
development of railways and connec-
tions thrived, the Great Western Railway
and the Cardiff Railway in 1903 and 2
steam rail motors built by the Glasgow
Railway and Engineering Company of
Govan, opened seven halts on route in
1904. (Railscot, 2014) The connections
over land resulted in the opening of
Queen Alexandra Dock in 1907 where
the land consisted of 165 acres of docks
and 38,000 feet of quayside. Relating to
the sustainability of the environment be-
cause it provided solid links for future
During the 1900s, workers were concerned
about reporting possible dangers and com-
menting on any issues in there work as they
could have lost their jobs. This was a big
problem as the practise of health and safety
should always be a priority. In relation to
the Newport Dock collapse, it is reported
that witnesses came forward after the col-
lapse and spoke of temporary props falling
in the northern part of the trench, and the
sides of the channel falling in the southern
part of the trench. Another called attention
to the pressure on the sides caused by the
weight of the concrete mixer, crane and
wagon roads. However, unlike modern day
projects, there was no health and safety of-
ficer or much enforcement and protection
for workers, the difference in class in socie-
ty often meant the working class were ex-
ploited.
Analysis of the Project
The Newport Dock disaster occurred during the early 20th centu-
ry, a period in which the Engineering projects undertaken were
being carried out with considerably less technical information
available to them in comparison to that currently available to En-
gineers. This lack of information led to shortcomings in all areas
of the identified themes of failure. Although Easton Gibb & Son
were acknowledged experts in the type of construction underway
at the dock, their construction methods and safety measures
would not stand up to the scrutiny of the 21st century.
In the case of the Newport Dock disaster, it could be argued that
the greatest shortcoming of the Newport Dock extension was
Easton Gibb & Son’s procedures when malfunction occurred, not
the construction methods themselves. Per W. W. Squire
(p5,1909), Any movement of the piles or support timbers was re-
ported directly to the Walking Ganger, who would then make re-
inforcements and decisions at their own discretion. The lack of a
defined route of action for the walking ganger to take upon re-
ceiving reports of movement meant they were under no obliga-
tion to take any measurements or further investigate the reason
for the movement. This was a failure of both management, for
not setting out a clear and safe procedure for dealing with timber
movement, and workmanship for not securing the timbers
properly.
Ultimately "The contractors seem to have taken all reasonable
and proper steps in considering the scheme of timbering by con-
sultation with their staff of assistants and gangers, and with Mr.
Davidson, their consulting engineer." (Squire, p5, 1909). The in-
quest found that due to the large amount of possible contributing
factors no one person was at fault because nobody had all the re-
quired information to ascertain that there was a risk of failure.
This was a serviceability failure because the structure was put un-
der loads inhibiting its proper function, and deflected excessively.
Key Project Facts
Date: 21st May 2000
Contractor: Hewden Tower Cranes Ltd or
Kvaerner Cleveland Bridge (KCB)
Client: Canary Wharf Contractors Ltd
Structure: Wolff WK 320BF Tower Crane
Function: Construct HSBC skyscraper
Fatalities: 3
Project Overview
3 Hewden Tower Cranes Ltd workers were killed when a 450 foot high crane crashed to the ground.
The structural failure occurred during the phase of construction known as ‘climbing’, a routine oper-
ation. Hewden’s specialist team, consisting of 6 experienced people, were adding another section,
for the fifth time that weekend to the 25th storey, when at approximately 3.50 pm the crane began
twisting. This operation is relatively rare in the UK; usually tower cranes are assembled to their full
desired height when first taken to site.
Two members of the erection crew and the crane driver working on this tower crane were killed as a
result. Two other erectors working with them on the crane survived, as did an assistant on the
ground. Two other erectors working with them on the crane survived, as did an assistant on the
ground. The fatality of the collapse could have been considerably high had the road outside not been
temporarily closed, or it had been at a busy time of day.
Final Discussion and Conclusions
In conclusion, it is clear when looking at the attitude of employees across both disasters, that the last century has seen a massive im-
provement in how information and concerns are relayed to senior employees, with the capability to assess the situation and prevent
failure. It is paramount for all employees to work together, without fear of repercussions, to maintain safe working conditions.
Another shared factor of failure in each project was relying solely on the opinion of senior employees. Taking from this, it is evident
that clear standards need to be adhered to, and the stability of structures should be based upon measurements and known physics,
not the discretion of the supervisor.
Petroski (2006, p3) argues that successful design and failure are inherently intertwined, meaning that learning from the failures of
the past is crucial to successfully and safely carrying out Engineering projects in the current day and age.
The shortcomings of the Newport Dock Disaster of 1909 and the Canary Wharf Tower Crane Collapse of 2000 has taught us as
young Engineers that the practice of health and safety should always be considered throughout the design process through to imple-
mentation of a project.
http://www.newportpast.com/
http://quietwomansrow.com
- This shows the aftermath of the collapse of the dock
http://
par-
lipapers.proquest.com/
parlipapers/result/
pqpdocumentview?
ac-
countid=12860&group
id=99944&pgId=d7ae
ab46-f4c4-4eb6-b747-
08226ca20e07
- view of the timber
support system in the
trench
http://www.cranestodaymagazine.com/news/lessons-from-
canary-wharf/image/lessons-from-canary-wharf-131209.html
- This shows the aftermath of the collapse of the crane
Reference List:
Petroski, H (2006) Success through failure the paradox of design. Princeton University Press: Oxfordshire.
Squire, W. W. (1909) Report to The Secretary of State for the Home Department on the Disaster at the Alexandria Dock, Newport, House of Commons Parliamentary Papers
Online.
No author, http://parlipapers.proquest.com/parlipapers/result/pqpdocumentview?accountid=12860&groupid=99944&pgId=d7aeab46-f4c4-4eb6-b747-08226ca20e07 Accessed
28/02/2017
No author, http://www.railscot.co.uk/Alexandra_Docks_and_Railway/frame.htm, 2014 Accessed 28/02/2017
No author, (2002) http://www.hse.gov.uk/construction/crane/report.pdf Accessed 28/02/2017
No author, http://www.personneltoday.com/hr/no-evidence-for-action-over-triple-death-crane-collapse/ Accessed 03/03/2017
World Development, http://www.un-documents.net/ocf-02.htm Accessed 05/03/2017
This picture
shows a
climbing
frame being
used to in-
crease the
height of the
crane, it is not
a picture from
the site of the
accident, but
something
similar. http://
www.cranecr
ews.com/
crane-blog/
how-do-tower
-cranes-climb
Other contributing factors of Failure:
Large amount of rainfall prior months
Extra pressure on the northern side of the trench due to the
weight of the dam
Timber movements were secured based on the discretion of
the walking ganger
Work was left incomplete allowing movement of the piles
making subsequent efforts to secure the piles less effective
Possible lack of consistent timber – no records available
No efforts made to calculate the force the timbers would be
baring
Economic Social Environmental
Wolffkran’s pioneering innovation
in luffing crane technology can be
transported easily and economically
and erected extremely fast
considering its size.
Cranes are not often alike because
they are made to match the
requirements of the job that it will
undertake, therefore once the job is
finished there may not be a use for
the crane and this is a waste of
materials.
Cranes are used continuously in
construction, producing a large amount
of carbon emissions. Also, the materials
used to construct the crane, sometimes
coming from other parts of the world,
could already have a large carbon
footprint.
Specific high-strength steels were
partially implemented in the construction
the tower system so as to increase the
performance and to extend the
serviceable lifespan of the tower element.
The custom luffing jib crane offers
unique installation flexibility. It can be
safely parked for wind speeds up to 130
km/h with its slew brakes on.
A crane replaces the need for people to
move heavy loads themselves and
therefore this reduces the risk of injury
and over working. Cranes make
construction a lot more time effective
and a less strenuous task – overall a
more inclusive job.
The Health & Safety Executive (HSE)
has decided there is insufficient
evidence to support any action
regarding the tower crane collapse. As
a result of this, the unexplained tragedy
could have turned people off working
on cranes due to uncertainty with
regards to their safety.
An 'open verdict' was the official HSE report conclusion, as
there was no definitive cause of the crane collapse. No area
was significant enough to have caused the failure of overload-
ing and deformation of the top front guide wheels, the cumula-
tive stress increased the damage done.
The day before the accident the crane driver had never
‘climbed’ before. He followed the supervisor’s instruc-
tions but when he was in the crane cab, isolating controls and
applying the slew brake, he was concerned about the erratic
movement, and after discussing this with the supervisor, he
came then down from his cab between each climb.
On the day of the accident, a more experienced driver took
over and the 'climb' proceeded as usual. Two men were work-
ing on the upper platform of the climb rig, two on the lower
platform, the driver stayed in his cab throughout the climb and
a trainee was on the ground, slinging loads. At around 3.50pm,
they were moving the last mast section from the traverse car-
riage platform into the frame. Whilst doing this one of the erec-
tors on the lower platform noticed one of the guide
wheels moving laterally around one of the legs of the mast. The
two erectors on the lower platform jumped onto the metal lad-
der inside the mast and managed to move down, they then
could see the climbing frame tilting about the north east
leg. The mast then started to violently shake, the two erectors
on the ladder managed to cling on, but when the shaking
stopped they saw that the new mast section and the top of the
crane had overturned and fell 120 meters onto the sight be-
low, fatally injuring the crew above.
When the wreckage was examined by HSE, the sections
showed a structure typical of low carbon steel, a metal well
suited for welding. One end had completely failed through the
weld, and appeared to be a typical failure of overload, the other
end had failed through the weld connecting a small end plate to
the climbing frame. The western and upper end of the upper di-
agonal member had failed through approximately 75% weld
metal and 25% parent metal. The east end failed around ap-
proximately 75% of the member and therefore was still at-
tached to the east leg of the climbing frame, the failure mode
appearing typical of a fracture caused by ductile shear. The
west end of the lower diagonal member had failed in a similar
manner, with partial failure through the weld metal, this had re-
sulted in the crushing of the end of the member. Other members
also became detached, as the welds tore off and fractured, due
to overload. The materials weren't strong enough to cope with
the excess stress they had to support when the crane started to
fail, but they weren't designed to go wrong, and therefore sup-
port that excess load. This is only the second accident of its
kind in history.
The supervisor in charge had 15 years experience in climbing,
and his team were also well experienced, but there is no official
training for crane climbers, they learnt by instruction and work-
ing with an experienced supervisor. Because there is no official
training, there is also no official qualification and evidence. It
may be beneficial in future to ensure there is recorded training
and a qualification as proof.
The men were expected to work long hours, away from
home, each signing voluntary exemptions to the 48 hours per
week limit regulations. Hours were recorded and it was aimed
to give erectors 78 hours a week, giving them a day off if that
figure was exceeded, but this was not always possible. They
had worked 79 hours that week, yet had done 87 hours the
week before. The crew need concentration throughout the oper-
ation, relying on their experience of the climbing system and
visual clues to identify important changes in conditions. This
could be seriously compromised by the hours they were work-
ing.
The management could have done more to prepare their
staff, ensuring all their equipment was in perfect working order
and present, so that the men weren't being put in
any unnecessary danger. The climbing frame did have a slight
bow in one member, but it had been present for a few months,
and it had been adequately bolted to make allowance for the
bow. The supervisor had sought advice from his superiors, but
it had not been deemed serious. There was no anemometer fit-
ted in the crane, a device to measure wind speed, reliance was
placed on other crane drivers. On the day of the accident it is
reported there were no weather problems, HSE checked this
with the Meteorological Office.
A balance was not used when adding height to the crane, as
recommended, but doing so without a balance would not have
caused the incident. The experienced supervisor used a trial and
error method to determine the radius required to keep the crane
balance whilst extending its height, instead of calculating it.
The theoretical radius for balancing the crane without a balance
weight has been estimated at 31m. A few minutes before the ac-
cident, a site worker was taking pictures of the crane nearby,
and from these pictures the radius has been estimated at about
28m, but the frame was so damaged in the fall, an estimate was
all that could be given. A difference of a few meters would not
have caused the fall, but proper calculations for a radius would
be recommended, especially when doing one of the most dan-
gerous jobs in the construction industry.
There can be no definitive type of failure, but after analyzing
all the research, a disconnection failure because the members of
the structure did become separated.
Analysis of the Project
The Pillars of Sustainability
The main aim of structural design is to design a safe structure that will fulfil its intended purpose.
The structure should be able to resist the predicted loading for its entire design life with a sufficient
margin of safety. Structural design is an integral part of construction, even a small chance of failure
is unacceptable.
Sustainability is described as development that meets the needs of the present without
compromising ability of future generations to meet their own needs. Sustainability in engineering
is vital as we are currently using up the Earth’s future resources, we are destroying our own
environment on a global scale in the pursuit of economic gain and resources of Earth are not
sufficient to sustain even current human population of the world.
Environmental sustainability is the ability to maintain rates of renewable resource harvest,
pollution creation, and non-renewable resource depletion that can be continued indefinitely.
Economic considerations have always been an integral part of engineering design and a force for
refinement and sophistication of design methods. Social sustainability is the ability of a community
to develop processes and structures which not only meet the needs of its current members but also
support the ability of future generations to maintain a healthy community.
-Plan of the
section of the
west wall
where the
collapse oc-
curred
http://parlipapers.proquest.com/parlipapers/result/pqpdocumentview?
accountid=12860&groupid=99944&pgId=d7aeab46-f4c4-4eb6-b747-08226ca20e07
- view of timber supports in the system of the trench
W15008927, W15008100,
W16002973, W16037749