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USE OF ICE PLATFORMS FOR BRIDGE CONSTRUCTION
Dr. S. Balakrishnan, Ph.D., P.Eng.
Associated Engineering Alberta Ltd.
David Andres, M.Sc.CE, P.Eng.
Trillium Engineering and Hydrographics Inc. Edmonton, Alberta, Canada
Extreme cold weather resultsinwinter construction problems such as decreased
human productivity, increased brittleness of materials, and susceptibility
of concrete to freezing. On the other hand, extended cold temperatures offer
several advantages such as accessibility to remote areas, natural working platforms
on rivers and lakes, and increased load resistance from frozen ground.
This paper documents the use of ice as a construction material for work
platforms from which heavy civil engineering structures such as bridges can
be built. Girder erection for the 400 m long ‘Suncor’ bridge
over the Athabasca River near Ft. McMurray was carried out off an ice platform
in the river. Because of the short construction window, there was a need
to optimize the thickness of the ice bridge to minimize both its construction
time and the risk of failure under the design load. The paper describes methods
used to assess the structural characteristics of the ice sheet and design
considerations used to determine its bearing capacity under a variety of
both transient and stationary loads.
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INTEGRAL
ABUTMENT BRIDGES - DESIGN AND CONSTRUCTIBILITY
David I. Harvey,
Don W. Kennedy
Associated Engineering, Canada
Gordon W. Ruffo
Carston-Aimes
Construction Consultants Ltd., Canada Opened to traffic in
the fall of 2001, the 300 km long, $1.3 billion Vancouver Island Highway Project
took more than a decade to complete. The new highway required over 150 bridges
and is located in the most seismically active region of Canada with peak design
rock acceleration of up to 0.47 g. Experience has shown that costly and
disruptive bridge maintenance has resulted from expansion joint leakage. Most
bridges, however, are relatively short, and the opportunity to eliminate expansion
joints exists. As a result, the Vancouver Island Highway Project Management Team
encouraged its design consultants to consider the use of integral abutments, and
more than 20 were built. While cost-effective and durable, there are construction
implications. Previous users of integral abutments have reported on typical
details and design rationale, and there has been at least one in-depth study of
soil/structure interaction behaviour. Although these sources were referenced during
design development for the Vancouver Island Highway, some different concepts emerged. The
paper describes the various types of jointless bridges on the Vancouver Island
Highway, and the justification for their use. The associated construction issues
are explored, and recommendations for their application are given. Read
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LOW VOLUME ROAD BRIDGES
- DESIGNS FOR REMOTE LOCATIONS David Harvey, Martin Jobke, Julien
Henley
Associated Engineering, Canada Low volume roads
often demand a different approach to bridge engineering, and this is particularly
true for construction in remote locations. Standards commonly used for high volume
roads are excessive for low volume applications. Roadway width, sidewalk provision,
barrier details and approach flares all need to be addressed for the specific
applications. For remote sites, bridges are commonly single lane structures
using either twin steel I-girders and precast concrete decks or shear connected
precast concrete beams. Curbs and substructure have also been modified to suit
various applications. The remote locations for typical low volume road bridges
include coastal sites where construction access may be by barge, and northern
sites where access would typically be limited to winter roads. Each remote location
has its own influence on bridge design. This paper presents typical low
volume bridge designs and how they have been adapted to suite various markets. Read
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THUNDER
BAY MICROFILTRATION FROM PILOTING TO FULL SCALE TREATMENT Patrick
W. Given, M.Sc., P.Eng.
Dennis Mutti, M.A.Sc., P.Eng.
Contact:givenp@ae.ca
Doug Scott, P.Eng., City of Thunder Bay, Thunder Bay, Ontario
Darrell
Matson, City of Thunder Bay, Thunder Bay, Ontario
The
Ontario Ministry of Health placed a boil water advisory on the City of Thunder
Bay following detection of a Giardia cyst in the water supply. The advisory impacted
only the portion of the water system served from Loch Lomond, a pristine lake
in a protected watershed. Two microfiltration (MF) pilot plants were tested
on the Loch Lomond water supply with and without chemical coagulation, and on
the City’s second source – Lake Superior – without chemical coagulation.
Particle challenge testing showed that both test units could reliably achieve
4-log (99.99%) removal of 2-15 m size particles. With chemical coagulation,
significant colour removal could also be achieved. The successful pilot test
program led to the fast-track design and construction of a temporary MF facility
which enabled lifting of the boil water advisory. Performance of the facility
has exceeded expectations. The facility not only is removing cyst-size particles,
but also some colour constituents to the extent that disinfection byproducts from
chlorination of the filtered water appear to have been reduced. The equipment
supplier now classifies the membrane treatment facility as an ultrafiltration
plant. Successful experience with the pilot MF and temporary ultrafiltration
facilities has provided confidence leading to the City’s decision to incorporate
the ultrafiltration equipment in a permanent facility.
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TREATMENT
TECHNOLOGIES FOR FOOD PROCESSING WASTEWATER
Patrick W. Given,
M.Sc., P.Eng.
Barry Vallance, P.Eng.
Jan With
Contact:
givenp@ae.ca This paper reviews advanced technologies for
treating wastewaters from food processing industries, in general, and sugarbeet
processing facilities, in particular. The review composed an integral part of
Rogers Sugar’s plans to expand and upgrade its Taber factory in southern
Alberta. The wastewater component of the project first addressed a new, stringent
wastewater discharge bylaw which required the factory to implement pretreatment.
Subsequently, following detailed study, Rogers Sugar elected to go beyond the
bylaw requirements, and construct a combination of anaerobic and aerobic wastewater
treatment facilities which would meet more stringent standards, enabling direct
stream discharge. Reviewed anaerobic treatment technologies include
anaerobic contact, anaerobic fluidized bed, and upflow anaerobic sludge blanket
reactors. Reviewed aerobic treatment technology focuses on activated sludge with
nitrification-denitrification. Several facilities in the United States and Europe
were visited to assist in the technology review. The technology reviews
were paralleled by performance specifications and bid invitations to vendors with
recognized experience and expertise in designing and supplying facilities for
treating sugarbeet wastewater. Currently, the advanced anaerobic-aerobic wastewater
facilities are undergoing commissioning. The plant is designed to remove in excess
of 99% of incoming BOD loads and to nitrify-denitrify.
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SOME INNOVATIONS IN BRIDGE
ENGINEERING - PRACTICAL EXAMPLES
S. Balakrishnan, P.Eng.
Contact: balakrishnanb@ae.ca
Three examples incorporating some innovative approaches used to solve bridge
design and rehabilitation problems are described. The first example deals with
the rehabilitation of a 168 m steel girder bridge damaged due to undermining of
a pier by scour. The stresses were relieved from the superstructure, which was
then used to support pile driving equipment. Pile bents were installed immediately
upstream and the superstructure was transferred over onto new pile bents. The
second example involves modification of a bridge to act as a water retaining structure
under flood conditions. The third example involves an interchange with 65 degree
skew. The economical solution was to provide a bridge with square ends and longer
spans. Post-tensioned concrete diaphragms were cantilevered at piers to support
the exterior steel plate girders.
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me the paper...
INNOVATION
IN DESIGN/BUILD BRIDGES — A. B.C. PERSPECTIVE David I. Harvey,
P.Eng.
Contact: harveyd@ae.ca Recent
initiatives on British Columbia Ministry of Transportation and Highways bridge
projects have demonstrated that better value can be obtained through design innovation.
As a result of the Ministry including Value Engineering clauses into the bridge
construction contracts, the contractor was able to offer cost-saving alternative
designs which were tailored to the specific constraints and requirements of each
project. Five Value Engineered bridge designs were offered in 1996 and 1997. These
resulted in a net savings of over $1 million. The owner obtained better value
through the integration of design with construction and the incentive of the Value
Engineering clauses. All five designs involved the creative use of precast concrete
bridge girders.
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paper...
COST-EFFECTIVE
BRIDGE MODIFICATIONS
John B.
Fussell, P. Eng.
Contact: fussellj@ae.ca
Paper
prepared for presentation at the Structures Session of the 1999 Annual Conference
of the Transportation Association of Canada Saint John, New Brunswick
As
a result of the aging bridge population and increased volumes of traffic, Canadian
municipalities have been faced with the thorny issue of bridge upgrading. Many
bridges require improved pedestrian facilities or safer traffic barriers. Others
are suffering from increased axle loads and require deck improvements. Some bridges
are functionally inadequate and need widening. Some of these structures
are in good condition, others have deteriorated decks on sound substructure. Few
are candidates for complete replacement. Under current budget constraints, ways
to utilize the residual life expectancy needed to be found, which required creative
solutions to be developed. Associated Engineering firm has undertaken many
such projects and describe cases of innovative designs that proved constructible,
reduced maintenance, and were highly cost-effective. None were 'traditional' solutions
to bridge engineering problems. Examples include: - Concrete deck overlays
to strengthen timber deck bridges,
- Deck slab overlays for timber superstructure
replacement,
- Supplementing existing stringers with new members,
- Precast
removable shear-connected slabs for timber superstructure replacement,
- Provision
of a separate pedestrian structure to permit deck widening and safety improvements,
- Lightweight short-span pedestrian trusses,
- Strengthening weakened abutments
by backfilling, and
- Traffic barrier upgrades for aging bridge superstructures.
The paper describes the situation prior to the improvement and examines
the alternative solutions. The advantages gained by the improvement and the method
of using the residual life expectancy of the structure are described.
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DYNAMIC ANALYSIS OF ICE FORCES
ON ATHABASCA RIVER BRIDGE PIERS
The piers of the Suncor Bridge over the Athabasca River consist
of two 2.4 m diameter columns, rock socketed into limestone. This is considered
"flexible" as per CSA S6 and a dynamic analysis is required. The paper
describes mechanisms producing ice forces and the dynamic analysis, including
Eigen value and time - history analyses. Since the superstructure serves to distribute
the load on piers, the entire structure was modelled using frame elements for
pier columns and girders and shell (plate) elements for deck and diaphragms. Spring
elements were used to model the soil resistance. Two major failure types of ice
floes were considered in developing the input forcing function: (1) crushing failure
where the full width of the nose is in contact with the crushing ice; and (2)
impact failure, where the ice floe is brought to a halt before full width of the
pier is in contact. The results of the dynamic analysis are compared with those
obtained using the static analysis. Typical time - history plots of displacement,
velocity and acceleration are provided. Some recommendations for revisions to
code provisions are given.
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me the paper...
NIPAWIN SEWAGE FORCEMAIN
A
directional drilled crossing of the Saskatchewan River Rod Karius, P.Eng.,
Contact: kariusr@ae.ca
From a global perspective, directional drilling is not a new construction technique.
It was adapted in the early 1970s from oil well drilling technology. Initially,
its use was limited to steel pipeline construction in the petroleum industry for
crossing under natural and manmade obstacles such as rivers and highways. In the
1980's, the technology was applied to water transmission lines and sewage forcemains.
Today, directional drilling is used not only for the installation of pipelines
but also electrical and communication cables. Installations have been as large
as 1200 mm in diameter with distances exceeding several thousand metres. In contrast
to the apparent broad usage of directional drilling, the application of this technology
to water and wastewater pipeline installations in Western Canada is still relatively
rare. In researching the use of horizontal directional drilling for the installation
of a polyethylene sewage forcemain across the Saskatchewan River at Nipawin, Saskatchewan,
no other installations of similar pipe material or diameter were found in Western
Canada. This paper documents the case history of the directional-drilled
river crossing at Nipawin. The project is noteworthy in terms of the size of pipe
installed (large for polyethylene), length of the crossing, depth of the river
valley and variability of the soils encountered. The paper provides a comparison
of the costs and environmental impacts for both conventional open cut and directional
drilled crossings. Also presented, is a review of the technical considerations
that apply to the design of a directional drilled crossing as well as the contractor's
proposed and actual methods of dealing with the technical challenges presented
by this particular crossing.
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LGAA PRESENTATION: INFRASTRUCTURE MANAGEMENT PLANS
Dieter G. Foessel, M.Sc., R.E.T.
Contact: foesseld@ae.ca
Municipal infrastructure systems are major capital assets that need to be
managed, maintained and periodically upgraded if they are to provide the level
of service and performance for which they are intended. In order to achieve
this objective, municipal Administrators need the information that an Infrastructure
Management Plan (IMP) provides so that the infrastructure system(s) can be
planned and managed in an orderly, phased manner. Once an Administrator has
the IMP information, he/she has the necessary information to compile a planning
document from which short and long term capital plans may be developed.
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SUNCOR BRIDGE: A CASE STUDY
IN INNOVATION
John B. Fussell, P.Eng
Contact: fussellj@ae.ca
Having decided to proceed with the Steepbank Mine development in early 1996 on
an accelerated schedule, Suncor needed permanent access across the Athabasca River
by late 1997. A design/build contract offered the only feasible procurement method.
The successful contract represented innovation in bridge engineering, uniquely
blended design with construction resources, and needed to fit into a very tight
construction schedule.
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me the paper...
VANCOUVER INTERNATIONAL AIRPORT
NEW CATEGORY III RUNWAY LIGHTING SYSTEM
Douglas Falkins
Contact:
falkinsd@ae.ca November 4
,1996 marked a new dawn in Canadian Aviation history, with the opening of a new
Runway (08L-26R) at Vancouver International Airport. The opening of the new runway
not only relieves air traffic congestion at the airport, but also allows flights
in and out of Vancouver in weather conditions which previously shut down the airport,
causing flight delays and cancellations, which affected the entire Canadian aviation
system. This significant step forward is due to the installation of the latest
generation of electronic landing guidance and lighting systems on the new runway
to Category IIIA standards allows aircraft to land in visibility conditions as
low as 200 m (600 ft). Previously, visibility less than 400 m (1400 ft) would
shut down the airport for landings. Vancouver International Airport (YVR)
is located on Sea Island in Richmond B.C., which is a suburb of Vancouver B.C.
The airport is the second busiest facility in Canada, serving 14 million passenger
per year, and over 500 flights a day. In 1992, the Vancouver International Airport
Authority took over responsibility for the operation of the airport from Transport
Canada, and immediately began planning an expansion program which included a new
International Terminal Building and the 3030 m (9941 ft) long runway, 12 new interconnecting
taxiways, 3 extensions to existing taxiways and an expanded terminal apron.
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LIQUID STREAM SECONDARY TREATMENT
PROCESS DESIGN AT THE ANNACIS ISLAND WASTEWATER TREATMENT PLANT OF THE GREATER
VANCOUVER SEWERAGE AND DRAINAGE DISTRICT
Rick Corbett P. Eng.,
Lloyd Slezak P. Eng., Kim Fries P. Eng., Les Pickard P. Eng.3, Lianna
Mah P. Eng., and Rudy Palsenbarg
Contact: corbettr@ae.ca
The Greater Vancouver Sewerage & Drainage District (GVS&DD) is a major regional
wastewater agency serving Vancouver, British Columbia and surrounding municipalities.
In the late 1980's it was mandated to upgrade its largest treatment plant from
primary treatment to secondary treatment. From 1990 until the present the GVS&DD
has engaged in Predesign, Design, Construction and Commissioning of the Annacis
Island WWTP Secondary Upgrade. The size of the facility and the fact that no secondary
treatment components were previously in place combined to make the upgrade a very
large project valued at nearly $470 million CDN. This paper describes the major
project components of the liquid stream process improvements. In addition to the
major biological treatment components, other aspects of the project are described
including, odour management, influent pumping, and primary treatment upgrades.
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SLUDGE AND SCUM SCREENING
AT THE ANNACIS ISLAND WASTEWATER TREATMENT PLANT
Lianna Mah P. Eng.,
Steve Krugel P. Eng., and Rudy Palsenbarg
Contact: mahl@ae.ca
In 1991, the Greater Vancouver Regional District (District) began design of the
upgrade of the Annacis Island Wastewater Treatment Plant to secondary treatment.
During the design, the District adopted a policy requiring that all biosolids
generated from treatment be used beneficially. Removing debris from the biosolids
is considered crucial to developing market acceptance of the product. In addition,
removing or grinding material larger than 12 mm in the solids stream is required
to avoid blocking process equipment. In North America, grinders are most commonly
used to macerate sludge and scum. In Europe, screens with an opening size of 10
mm or less have been successfully used for removing debris from solids streams.
The advantages of screening over grinding are lower capital cost if a significant
number of grinders can be eliminated, a reduction in the quantity of debris entering
the digesters and, as a result, reduced frequency of digester cleaning, reduced
frequency of maintenance of equipment in the digester area, and less debris in
the digested biosolids. Sludge and scum screens began operation in April 1996.
This paper discusses the rationale behind the selection of these screening processes,
the technology selection and design, and initial operation of the screens.
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CLEARWELL DESIGN FOR OPERATIONAL
AND CT CONSIDERATIONS AT A LARGE CONVENTIONAL WATER TREATMENT PLANT
Barry Vallance, P. Eng. and Doug Jamieson, P. Eng.
Contact: vallanceb@ae.ca
Faced with more stringent regulations and growing public expectations regarding
drinking water quality, the City of Calgary's Glenmore Water Treatment Plant was
in need of upgrading if it was to serve the City into the next millennium. A comprehensive
study and pilot program was undertaken to determine how best the plant could be
upgraded to meet the water quality and demands for the foreseeable future. The
result was a four phase strategic plan, the first phase of which was to upgrade
the existing facilities to meet improved particulate removal and disinfection
goals. This paper will present the development of a clearwell design that would
meet the disinfection goals while also providing the plant with much needed operational
storage. Various site constraints and design criteria that needed to be addressed
while meeting the dual requirements for disinfection and operational storage will
be discussed. These will include: - varying demands throughout the year
- physical site limitations
- maximizing use of existing clearwell storage
- minimizing headloss conditions to reduce excavation costs
- limiting chlorine
residual levels to avoid exacerbating finished water taste and odour
- ceasing
prechlorination during periods of high source water organics levels
- ensuring
disinfection byproducts would not exceed the established goal
- additional operational
storage to provide the operator adequate time to react to variables
The new AEP Guidelines for disinfection which now focus on removal of protozoan
cysts and viruses will be presented as they apply to the Glenmore WTP.
On the
basis of the required operational storage and disinfection CT, the size, arrangement
and T10 for the clearwell will be discussed and how the varying demand during
different seasons of the year was taken into account in arriving at the final
sizing and depth of the clearwell. The opportunity to reduce construction
costs and the analyses that lead to the final design will also be presented.
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DRAINAGE IMPROVEMENTS IN A BUILT-UP
AREA
Gord Geoffrey, P.Eng.
Contact: loewend@ae.ca
The analysis and implementation of drainage improvements in a built-up area should
be based on a comprehensive understanding of the behaviour of the existing drainage
system. This understanding is only available through interpretation and analysis
of all available information. Information that must be considered includes system
record information, flooding and insurance claim information, computer modelling
results and public consultation.
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me the paper...
AN INNOVATIVE APPROACH TO DEVELOPMENT
OF A REGIONAL stormwater MANAGEMENT FACILITY
Herb Kuehne, P.Eng.
and J. Cairns, P.Eng.
Contact: kuehneh@ae.ca
The paper will provide an overview of an innovative approach to the development
of a regional stormwater management facility. The City of Edmonton is improving
Whitemud Drive between 34 Street and Highway 14, and Associated Engineering was
retained to design and oversee construction of the stormwater management system.
Rather than simply design a system that accommodated the increased runoff from
the improved freeway, it was designed to incorporate runoff from future developments
in the upstream basin and reduce flooding downstream, and thus become a regional
stormwater management facility for the City. The land surrounding the Whitemud
Drive site is largely undeveloped at this time. The Fulton Creek drainage course
runs through the site, and was incorporated into the design. The stormwater management
facility was designed to accommodate existing upstream runoff in the Fulton Creek
basin, and also to mitigate flooding potential in the downstream basin due to
future increases in runoff from the Free improvements and anticipated development.
Environmental enhancement of the Fulton Creek drainage course was included in
the design, and the new retention pond has been designed as an extensive wetland
area for wildlife. The facility was designed to minimize operation and maintenance
costs for the City. Material excavated for the wetlands area was utilized as borrow
material for the freeway construction work.
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me the paper...
SPENT LIME AS AN AID TO PHOSPHORUS
REMOVAL
Barry Vallance, P. Eng. and Ted Adamus
Contact: vallanceb@ae.ca
The NOVA Chemicals Plant at Joffre, Alberta is undergoing an expansion of its
production facilities. The expansion will require upgrading the site's water supply
and treatment and wastewater handling systems. The Red Deer River is the source
of water used on site. The main demand for water is from the various cooling systems.
Source water is reduced by cold lime softening prior to use. The spent lime from
this process is currently land applied onto local farmland. Waste streams
generated on site include cooling tower blowdown which is relatively high in orthophosphates
- up to 15 mg/L - that need to be reduced to less than 2.5 mg/L (1 mg/L as phosphorus)
prior to discharge back to the Red Deer River. A detailed bench scale and
follow-up pilot scale program was undertaken to evaluate phosphorus removal by
chemical coagulation using the spent lime from the water treatment process as
a source of alkalinity and an aid to coagulation. This paper discusses the
rational for looking at this and various other chemical combinations to address
this problem, and will present the full results of the investigation. The impact
of waste stream characteristics variability are discussed. Limited success was
achieved at ambient pH. A high pH process, which relied on achieving optimal pH
of 10.5 for precipitation of phosphorus was more successful and produced a settleable
floc. In either case the addition of spent lime was beneficial to the process
in reducing phosphorus levels and also reducing coagulant dose. The success
of this technology could see its potential application to municipal utilities
that practise cold lime softening and need to address phosphorus removal at their
wastewater plant.
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paper...
REACTING TO A DRINKING WATER
QUALITY CRISIS: A CASE STUDY ON THE CITY OF THUNDER BAY
Dennis
Mutti, P.Eng. Al Livingston, P.Eng. Doug Scott
Contact: wrighti@ae.ca
Many community water supply systems in British Columbia, and across Canada, do
not provide adequate protection against potential water quality problems caused
by the presence of Giardia lamblia cysts or Cryptosporidium occysts. One of
the major water sources for the City of Thunder Bay, Ontario is the Loch Lomond
water supply that provides raw water to the city via 4.5 km pipeline and tunnel.
Historically, the only treatment provided was chlorine disinfection and corrosion
control. In 1997, Giardia were detected in the water supply, resulting in an immediate
boil water order. What followed over the next year was the development and implementation
of a water treatment plan to deal with the crisis situation. The solution
implemented was the construction of a 40 ML/d water treatment plant incorporating
membrane filtration technology. Key to the successful resolution of the water
quality crisis was the city's ability to plan, pilot-test, design, construct and
commission the water treatment plant in less than a year. This involved engineering
studies and a series of public meeting to agree on the solution. Fast-track design,
equipment procurement, and construction then had to proceed on a greatly compressed
schedule. This paper describes the reaction of the City to the crisis, the
development of an action plan, and the design, construction and commissioning
of the water treatment plant.
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me the paper...
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President's
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Thunder
Bay Microfiltration from Piloting to Full Scale Treatment