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ESSENTIAL SOLUTIONS FOR A SUSTAINABLE TRANSPORTATION INFRASTRUCTURE


REDISCOVERCONCRETE

2 ESSENTIAL SOLUTIONS FOR A SUSTAINABLE TRANSPORTATION INFRASTRUCTURE

From high performance green buildings to durable and fuel efficient highways, long-lasting intersections, water permeable parking lots and more, concrete provides solutions to a host of pressing sustainability challenges. And it continues to push the boundaries of performance ev-ery day, making it an essential material in securing the climate resilient critical infrastructure of the future.

By weight, more concrete is used than all other construction materials combined — more in fact than any other material except water. And yet, concrete can be more or less invisible — an essential material that some take for granted simply because it is so common in their day-to-day lives.

We are at a critical juncture when it comes to the way we think about our built environment. Sustainability, and in particular the pressing need to mitigate and adapt to the changes in our climate, demands of us more holistic, integrated and innovative models and tools for planning, designing, building and managing our roads, bridges, utilities, hospitals, housing and even parking lots to prepare for uncertainties.

The challenge is all the more pressing because it comes at a time when huge investments are being made to repair and expand Canada’s aging infrastructure and address our enormous infrastructure deficit — esti-mated by the Federation of Canadian Municipalities to be some $171.8 billion for cities alone.

Among the most significant opportunities facing decision makers today is to chart the way for infrastructure decisions that favour durability, longevity, resilience and maximum value for taxpayers. On all these fronts, concrete products offer “win-win” or “no regrets” solutions to integrating sustainability and resilience into building and infrastructure projects.

In the pages that follow, the Concrete Council of Canada hopes to en-gage you in a discussion about durability, sustainability and resilience. And we invite you to rediscover concrete — the world’s most ancient building material — as the sustainable building and paving material of choice.

COVER: CONCRETE ROADWAY SYSTEM IN THE DETROIT, MICHIGAN AREA

BACKGROUND: IRVINE RIVER BRIDGE, ELORA, ON

RIGHT: QUEEN ELIZABETH WAY (QEW) ST. CATHARINES WIDENING, ST. CATHARINES, ON


Our built environment is at the heart of sustain-ability — the source of, and potential solution to virtually every sustainability challenge we face. How we design and build our communities has vast implications for energy use, transportation, water and wastewater management, food supply and distribution, our social and economic pros-perity and health, as well as our safety, security and resilience in the face of natural and human-made disasters. It’s no surprise then that cities — their planners, architects, engineers, asset managers, politicians and others — are at the forefront of sustainable innovation. New perspectives and new tools are reshaping the conversation about built infrastructure and the role that it can play in realizing a sustainable and resilient future.

Perhaps one of the most important tools to benefit from this attention on the sustainability of our built environment is Life Cycle Assessment (LCA). LCA recognizes the complexity hidden behind sometimes decep-tively simple questions about the sustainability of a product or service by examining all stages of its life, from “cradle-to-cradle” — i.e. raw material extraction through materials processing, manufacture, distribu-tion, use, repair and maintenance, and end of life (repurposing, reusing, recycling or disposal). LCAs are underpinning greater transparency in the marketplace through, for example, facilitating the development of Environmental and Health Product Declarations (EPDs and HPDs). They add rigor and credibility to the claims of product manufacturers about the impacts of their products and services.

At the same time, LCAs are not without limitations. In the same way that the whole isn’t always the sum of its parts, LCAs for individual products cannot be aggregated to give you a simple measure of a structure’s or a pavement’s overall sustainability.

The Canadian concrete industry has been working with experts from the Massachusetts Institute of Technology (MIT), the Athena Sus-tainable Materials Institute, the University of British Columbia, the

University of Toronto, the University of Waterloo and other Canadian academics to identify and measure what concrete contributes to the life cycle sustainability performance of buildings, roadways, and other infrastructure projects. In virtu-ally all cases, LCAs demonstrate how infrastructure professionals can leverage tremendous sustainability performance improvements through integrative approaches to materials and design.

Pavements are a case in point. Multiple studies have shown that the environ-mental impact from its “in use” phase outweighs all other phases of a pave-ment’s life cycle, including construction. Concrete’s durability means less energy is required to construct and maintain a concrete roadway over its life when compared to other pavements. More importantly, concrete also reduces the “in use” impacts; research at MIT1 and the National Research Council2 have shown that significant savings in fuel use can be achieved when vehicles travel on rigid concrete pavements. On a well travelled highway, the added fuel efficiency from a concrete surface imparts environmental and economic benefits that eclipse all other considerations.

As we think to the future of sustainable infrastructure, a key indicator of prog-ress will surely be the extent to which the transparency offered by LCAs and other predictive measurement tools is translated at the project level to leverage synergies between design, materials and technology and enhance the lifecycle sustainability performance of our communities.

PUTTING LIFECYCLE PERFORMANCE AT THE CENTRE OF SUSTAINABLE INFRASTRUCTURE

BACKGROUND: LAVAL LINE 2 METRO, MONTREAL, QC

1 Mehdi Akbarian, Franz-Josef Ulm, Model Based Pavement-Vehicle Interaction Simulation for Life Cycle Assessment of Pavements, Massachusetts Institute of Technology, Concrete Sustainability Hub, April 20122 G.W. Taylor, J.D. Patten, Effects of Pavement Structure on Vehicle Fuel Consumption, National

Research Council of Canada (NRC), 2002 and 2006

LEFT: CONCRETE ROADWAY SYSTEM IN THE DETROIT, MICHIGAN AREA


PAVEMENT LONGEVITY IN FOCUS

Well-known for its durability, low maintenance requirements and resilience, concrete contributes to longer-lasting, more cost-effective, and more energy-efficient roadways.


Despite regular maintenance and rehabilitation interventions, the busy urban intersection of Bloor Street and Aukland Road in Toronto was experienc-ing rapid deterioration of the asphalt pavement in rutting and fatigue cracking — deficiencies that reoccurred every few years. Bloor Street is a four-lane major east-west arterial road with an Average Annual Daily Traffic (AADT-2003) of over 30,000 vehicles and high peak hourly volumes of approximately 1,000 vehicles and in excess of 15 buses. It meets Aukland Road, a north-south collector road, forming a T-intersection. Aukland Road leads directly into the nearby Toronto Transit Commission’s (TTC) Kipling subway station, located approximately 500 metres south of the intersection. The high volumes of heavy transit bus traffic led to frequent pavement deterioration beyond accept-able levels. Furthermore, most of the vehicles, in particular the articulated buses, travelling through the intersection slow down to turn or stop for the traffic signal, causing severe rutting, shoving and other safety concerns.

In 2003, following a field visit to concrete overlay projects in the Detroit area, the City of Toronto turned to an unbonded concrete overlay to address the issue. They retained the University of Waterloo’s Centre for Pavements & Transportation Technology (CPATT) to conduct R&D and monitor the unbonded concrete overlay performance.

Based on the existing conditions and anticipated traffic loadings, the recommended alternative was a 150 mm unbonded concrete overlay with 25 mm high stability HL3 as a separation layer/bond breaker, on the milled and prepared existing concrete pavement for an 85 metre long section of Bloor Street. A 63 metre long section of Aukland Road was reconstructed as a conventional Jointed Plain Concrete Pavement (JPCP), 225 mm thick. Due to severe rutting into the aggregate base, 150 mm of the base was replaced. The existing and new pavement structures are illustrated in Figure 1.

The construction was staged in order to maintain partial access to traffic through the busy intersec-tion and reduce delays for the travelling public. The unbonded concrete overlay was placed over the course of two weekend closures in July 2003 and the full depth asphalt as well as part of the granu-lar course were placed at the same time.

FIGURE 1 Existing and New Pavement Structures

For research purposes, strain gauges were placed in the new concrete overlay and full depth concrete pavement to measure pavement responses over time in order to validate the pavement design. Sensors were also deployed and locations were strategically selected to capture the effects of accel-erating, slowing and turning traffic, as well as the overall effects due to environmental changes. Seven gauges were installed on Bloor Street and five were placed on Aukland Road.

The Bloor Street intersection was the first time the City of Toronto had constructed an unbonded concrete overlay. It has proven to be the right rehabilitation strategy for this previously distressed asphalt pavement. The overlay has provided over ten years of good performance and zero main-tenance. There have been no major functional or structural issues of note aside from minor cracking at the catch basin/manhole locations, mainly due to improper isolation and joint detailing. The recurring issues prior to rehabilitation — frequent rutting and shoving — have been totally eliminated. It is anticipated that this 11 year old unbonded overlay will have a service life of 25+ years, improving the return on investment and further highlighting its cost-effectiveness.

The performance of the Aukland Road jointed plain concrete pavement further supports that concrete is the right choice to mitigate rutting and shoving at intersections that are subject to high volumes of heavy traffic. Concrete pavement, which does not deform under dynamic or slow moving vehicles, maintains the safety characteristics of the roadway and averts the need for inconvenient and expensive maintenance work associated with other pavement materials.

Concrete Overlay Delivers 25 Year Service Life for Major Toronto Intersection

BLOOR STREET/AUKLAND ROAD INTERSECTION, TORONTO, ON, AUGUST 24, 2014

Aukland Road

New pavement

New pavementExisting pavement

Bloor Street

Existing pavement

LEFT: BAY STREET STREETSCAPE RECONSTRUCTION,

HAMILTON, ON


Fifteen years ago, the truck-stop on the corner of 118th Avenue and 170th Street in Northwest Edmonton was the first practical rest area for those travelling east on the Yellowhead highway from Jasper. This meant high traffic volumes for the intersection as transport trucks and tourists would turn in to refuel and refresh. The combination of volume and loading led to deep ruts in the approaches to the intersection. The city of Edmonton realized they had a maintenance issue on their hands and took action to repair the asphalt. After repeated attempts, it became evident that milling and filling of the pavement was not enough to prevent the significant rutting that would reappear in a short time. The City needed a solution that would give enduring performance, but not disrupt the busy intersection for a long period.

A thin concrete overlay proved to be a viable solution. A thin concrete overlay is a special sub-category of concrete overlay strategies in which only 50 – 100 mm of concrete is placed over existing pavement. The key to a thin concrete overlay is establishing an effective bond to the existing asphalt. The concrete provides a surface that will not rut or pothole and resists the compressive

forces of this high traffic scenario. The asphalt provides support for tensile forces for the concrete overlay as long as the bond remains intact.

The rehabilitation process for the intersection began on a Friday evening and was complete for Monday morning rush hour.

But the true accomplishment of the overlay continues to be seen a decade and a half later. Little to no maintenance has been conducted on the concrete pave-ment and the intersection is still performing well fifteen years later — the end of the pavement’s originally predicted service life.

Concrete pavement was the ideal solution for this problem and continues to provide a safe, cost-effective and resilient intersection for the City of Edmonton, ultimately saving time and money due to the elimination of repeated repairs.

Thin Concrete Overlay Still Performing in Edmonton after 15 Years

• Pavement longevity is a primary opportunity for increased sustainability.1

• Concrete pavements can have a service life of 50 years or longer, and have low maintenance and rehabilitation requirements during that time.2

• Concrete pavements’ durability and longevity minimize the consumption of natural resources for construction, maintenance, and rehabilitation activities.

• Concrete overlays can extend the service life of all types of pavement.• Over a 50 year period, the energy required for the construction, mainte-

nance and repair of a concrete pavement is one third the energy required for an asphalt pavement.3

• Concrete pavements have been shown to reduce heavy truck fuel con-sumption by a range of 0.8% - 6.9% when compared to asphalt.4

• The light color of concrete pavement reduces the amount of power needed to illuminate roads at night by up to 30%, saving on utility costs and helps mitigate the urban heat island effect, lowering cooling require-ments and smog generation.

• When designed with pervious concrete shoulders, they can minimize surface-water discharge and help replenish groundwater aquifers.

• Concrete is entirely recyclable and can be 100% reused as roadbed material.

• Concrete is made locally, lowering transportation related CO2 emissions and costs, and supporting local economies.

TEN KEY FACTS ABOUT CONCRETE PAVEMENTS & SUSTAINABILITY

1National Concrete Pavement Technology Center’s Sustainable Concrete Pavements Manual of Practice and the American Concrete Pavement Association’s Green Roadways Special Report.2Applied Research Associates, Equivalent Pavement Structural Design Matrix and LCCA for Municipal Roadways – Ontario, 2011

3Athena Sustainable Materials Institute, A Life Cycle Perspective On Concrete And Asphalt Roadways: Embodied Primary Energy And Global Warming Potential, 20064National Research Council of Canada (NRC) research, in 2002 and 2006; MIT’s Pavement Vehicle Interaction (PVI) research (2014) has found similar fuel savings on rigid concrete pavements

BELOW LEFT: RUTTED ASPHALT PAVEMENT, NORTH WEST EDMONTON, AB


Providing a smooth, safe, and quiet riding surface is always an important goal for pavement engineers. To achieve it, a balance between high friction level and low roughness and noise level needs to be attained. Diamond grinding and grooving are techniques that can be used to improve pavement smoothness while increasing driver safety by improving the frictional properties of the riding surface.

Diamond grinding is a process in which closely spaced diamond blades are used to remove surface imperfections such as faults, warp and curl to restore the surface to a smooth, level pavement and improve ride quality. The longitudinal texture that is created provides improved friction and low noise characteristics. The process is normally performed in conjunction with other Concrete Pavement Restoration (CPR) techniques such as full and partial depth repairs, dowel bar retrofit (DBR) and joint sealing and should be part of any comprehensive pave-ment preservation program.

The same technique and equipment is used for diamond grooving. However, while the purpose of grinding is mainly to restore ride quality and texture, grooving is generally used to provide escape channels for surface water, thus reducing the potential for hydroplaning. In terms of design, the main difference between grinding and grooving is in the distance between the grooves.

Grooving and grinding, along with associated concrete pavement restoration techniques, are all elements of the pavement preservation tool box used to prolong pavement life.

CONCRETE PAVEMENT PRESERVATION IN FOCUS:DIAMOND GRINDING AND GROOVING

Highway 75, Manitoba

In the spring of 2009, Manitoba Infrastructure and Transportation (MIT) determined it was time for repairs to Provincial Trunk Highway 75 — a main route between Winnipeg and the U.S. border. A 25.4 km stretch of this highway that extended from the town of Morris to the Marais River was in dire need of rehabilitation. The undoweled concrete pavement was 17 to 18 years old and most of the panels were faulted 10 to 15-mm causing tire thumping and a very rough ride.

Although an asphalt overlay was considered, MIT opted for concrete pavement rehabilitation because the projected costs were half as much. The methods selected included dowel bar retrofit, partial and full depth repairs, transverse joint sealing and diamond grinding.

The roadway now boasts a smooth riding surface with an increase in expected life span of 10 to 15 years. This will not only save the taxpayers money, but will provide for a smooth ride for years to come due to the addition of retrofitted dowel bars. With a project value of $9,000,000, the final cost of the dowel bar retrofit, partial and full depth repairs and diamond grinding was $360,000 (Canadian) per kilometer. Source: www.igga.net.

DIAMOND GRINDING HEAD


Highway 115, Ontario

Another example of concrete pavement preservation (CPP) can be found on a stretch of Highway 115 near Peterborough, Ontario. The section of concrete pavement was placed twenty five years ago, in 1989-1991, on some 55 lane-kilometers of the highway. There have been very few repairs to this pavement since then although there were four concrete CPP contracts to fix localized problems. Diamond grinding was performed in 2011 while diamond grooving and resealing of the joints were performed in 2014.

During a field visit to the concrete pavement preservation jobsite organized for the Ministry of Transportation of Ontario (MTO) in July 2014, attendees were able to see that traffic continued to flow past the worksite site unimpeded and how quiet the grooved surface had become. Source: http://www.igga.net/

With more than 90 percent of the Winnipeg’s street infrastructure being con-crete pavement, the City was looking for a means to restore and maintain the concrete pavement surfaces. It completed its first diamond grinding project in the summer of 2008, with a total of 119,500 square meters of diamond grind-ing on three major streets within the city limits. The project was undertaken to assess diamond grinding as a preservation treatment for concrete pavement of various ages. The streets completed were Kenaston Boulevard, a 250 millimeter plain doweled concrete pavement constructed in 1995, Brookside Boulevard, a 250 millimeter plain doweled concrete pavement constructed in 1997 and Plessis Road, a 230 millimeter plain doweled concrete pavement constructed in 2007.

Prior to diamond grinding, the streets were generally in good condition and had received full depth and partial depth repairs. The initial average Interna-tional Roughness Index (IRI) smoothness rating was 2.31 m/km on Kenaston Boulevard, 1.59 m/km on Brookside Boulevard and 2.93 m/km on Plessis Road.

The project specifications required that only the main lanes be addressed and that the final surface be uniform with 95 percent of the surface textured and ground in a longitudinal direction.

The final IRI was an average of 1.09 m/km on Kenaston Boulevard, 0.74 m/km on Brookside Boulevard, and 1.45 m/km on Plessis Road. The total cost of the project was $566,250 and was completed in 22 working days. The diamond grinding treatment process is expected to extend the service life of these pave-ments by at least 15 years. Source: www.igga.net.

FIVE KEY FACTS ABOUT CONCRETE PAVEMENTS & SPEED AND EASE OF CONSTRUCTION & MAINTENANCE

• Concrete roads can be opened to traffic within 24 hours — when fast track concrete is used, it can meet strength requirements in as little as 3 hours.

• Concrete road construction can take place at night, minimizing traffic disruptions.

• Cuts in concrete for utilities are easy to make — the city of Toronto has a road network that includes 80% composite roads and routinely performs over 25,000 utility cuts annually without undue delay.

• Concrete repairs will restore the pavement to its original condition while asphalt patches tend to not last as long as the original asphalt and tend to be noisier.

• Concrete overlays can be used to extend the life of all types of pavements.

Three Major Streets, Winnipeg, Manitoba

BELOW: HIGHWAY 115 CONCRETE PAVEMENT STRETCH, PETERBOROUGH, ON


FIVE KEY FACTS ABOUT CONCRETE PAVEMENTS & CONVENIENCE, SAFETY AND COMFORT

• Long lasting and requiring less maintenance, concrete pavements reduce traffic disruptions and commuter frustration.

• They don’t rut and minimize the potential for potholes. • They reduce the potential for hydroplaning, due to their non-rutting

quality.• They are brighter, which makes it easier to see objects on the road,

increasing safety.• Concrete pavements built today can have a reduced noise level that

is equivalent to asphalt’s, if not quieter, and provide as smooth a ride.

FOUR KEY FACTS ABOUT CONCRETE PAVEMENTS & COST OF OWNERSHIP

• Canadian cities could save up to 26% with concrete paving compared to asphalt when considering the cost of the pavement over a 50 year service life.1

• Research and real world examples show that concrete is competitive on initial construction costs and over the service life.2

• Awarding 10 alternative bid tenders to concrete pavement since 2001 has saved the Ministry of Transportation of Ontario approximately $45 million dollars.3

• CANPAV is a tool that helps decision makers determine the life cycle costs of different pavement options for projects of all sizes (http://www.canpav.com).

1 Applied Research Associates, Equivalent Pavement Structural Design Matrix and LCCA for Municipal Roadways – Ontario, 2011 2 Applied Research Associates, Equivalent Pavement Structural Design Matrix and LCCA for Municipal Roadways – Ontario, 2011 3 Ministry of Transportation of Ontario

Slow, heavy moving aircrafts can be extremely damaging for airport runway pavements. With aircrafts that can weigh over a million pounds landing on this structure, the pavement’s strength, high load-carrying capacity and durability are essential qualities. This is why rigid concrete pavement was selected for the $620 million runway expansion at Cal-gary’s International Airport (YYC). At 4 km long and over 60m wide, the concrete runway, the longest in Canada, can accommodate the largest planes in the world.

Concrete’s versatility contributed to the expansion being completed on-time and on-budget, and is literally the foundation of YYC’s future. The runway is the first phase of the major airport expansion project, with the next phase including a new 22-gate international terminal.

Concrete Pavement Strength and Durability Essential to Canada’s Longest Airport Runway

BACKGROUND: A CONCRETE AIRPORT RUNWAY


Rapid bridge replacement or accelerated bridge construction (ABC) is a technique that allows bridges to be replaced with minimum disruption to traffic. The replacement bridge is constructed on a site near the bridge to be replaced. When it is completed, the old bridge is cut away and removed using self-propelled modular transporters (SPMTs). Then the SPMTs lift the new bridge, transfer it to the work site and put it in place. Prefabricated precast concrete bridge elements for both the substructure and superstructure are a perfect fit for ABC.

Accelerated construction techniques should be used where the benefits of accelerated construction have a positive effect on the construction costs and impacts of the project. In many cases accelerated construction techniques can reduce overall project costs. The savings in accelerated construction projects are found in other aspects of the project such as time, equipment use and labor sav-ings. Decisions to use accelerated construction techniques should be made after considering the following issues:

•TemporaryRoadwaysandBridges•ReductionsinEnvironmentalImpacts•UserCosts•LongDetours

PORT MANN BRIDGE, BC

Port Mann Bridge, British Columbia

Back in the 1960s, the Coquitlam-Surrey area outside of Vancouver was home to some 800,000 residents. Today, 800,000 vehicles a week travel across the original five-lane bridge over the Fraser River. The new Port Mann Bridge significantly reduced the bottleneck – by as much as half. Ten lanes of traffic were open to traffic on what is the second largest bridge in North America, with twin deck towers rising 160 metres above the water. It is also the conti-nent’s longest cable-supported bridge (at 850 metres) and the world’s widest bridge, measuring 65 metres from side to side.

Precast concrete deck slabs were selected for the main span as they were the most economical, durable and an ideal structural solution for this composite bridge.

The project included 1,164 precast deck panels and 187 cantilevered sidewalk panels. The deck panels were unusual in that they incorporated over 10 per cent reinforcing – about 2,700 kilograms of reinforcing steel in each versus the more typical five or six per cent – to account for the live, dead and seismic loads to which the bridge is subjected.

Accelerated Bridge Construction


PORT MANN BRIDGE, BC

The Hodder Avenue underpass in Thunder Bay is proof that the extensive use of ultra-high-performance concrete (UHPC) in a modular project delivers versatil-ity, durability, and design excellence.

The Underpass is the first structure in North America to incorporate precast UHPC pier cap and pier column shells along with high-performance precast concrete box girders, parapet walls, and approach slabs. Field connections, joints and closure strips were field cast using UHPC, resulting in smaller, simpler joints with superior durability.

The bridge spans six highway lanes and is founded on a combination of hard till and bedrock.

The precast concrete design gave the project durability and much more. The precast prestressed concrete solution increased structural capacity and the design requirements while the UHPC allowed for smaller joints and improved durability, strength, and continuity.

The use of UHPC also enabled the design team to create a clean, open frame with sleek, elegant lines to meet the aesthetic goals of the Ministry of Transpor-tation of Ontario, North Western Region. The look was achieved through the use of a pier cap beam incorporated into the superstructure that spans continu-ously over the three pier column shells. Each shell has an octagonal shape,

which transitions from a smaller constant dimension at the bottom to a flared, larger dimension toward the top. The pier cap cantilevers at the ends with an inverted T shape to provide ledges upon which the box girders sit.

The pier cap was designed using prestressed UHPC with a compressive strength of 200 MPa, which allowed for just three pier columns and a more open appearance. This creates the appearance that the pier cap is integral with the box girders while seeming to provide a frame that goes directly into the superstructure.

The use of precast concrete accelerated completion of the project, with each of the sixteen girders per span requiring only fifteen minutes to be erected.

The project demonstrates that the use of precast ultra-high-performance and high-performance concrete bridge elements combined with field-cast UHPC connections gives designers an opportunity to advance bridge performance, shorten construction time, and extend the durability of these spans while delivering a resilient, attractive structure that is built to last. The Hodder Avenue Underpass was the recipient of the PCI Design Award in 2013 for the category of Bridges with Main Span from 76-149 feet and the Harry H. Edwards Industry Advancement Award, among others.

Hodder Avenue Underpass, Thunder Bay, Ontario

HODDER AVENUE UNDERPASS, THUNDER BAY, ON


New Highway 30, Montreal, Quebec

The development of Montreal’s Autoroute 30 represents a record-setting infrastructure project designed to ease commuting times for the city’s travellers. Linking municipalities located south of the St. Lawrence River, the Autoroute has become a highly desired route bypassing Montreal, alleviating congestion on the city’s busy highways and consolidating a number of other highways into a more effective transportation network.

Construction of the two main bridges crossing the St. Lawrence involved the use of precast girder beams measuring 45 metres in length — the longest beams of their type ever produced in Quebec. Another first was the use of precast deck panels for the bridge deck. The beams and slabs were erected easily and quickly, allowing for the concrete topping to be poured shortly after the precast concrete bridge deck was installed.

MAIN BRIDGES, HIGHWAY 30, MONTREAL, QC

Highway 407ETR Precast Culvert, Ontario

Culvert infrastructure has a variety of uses including short-span bridges, underpasses, stormwater and stream water conveyance. The supersized cul-verts installed off Anderson Street in Whitby, Ontario for Highway 407ETR fulfill all three of these uses.

The solution was an innovative, two piece, “clamshell” culvert that incor-porated a “cantilever” joint, allowing the contractor to place the culvert pieces using only a crane, eliminating the normal task of pulling the pieces together.

The culvert has a 2.1 metre interior height and an 8 metre interior span. Its spacious interior will allow wildlife to use the culvert as an underpass. It is a design that is popular in Alberta and British Columbia as it allows the underpass to give animals a safe passageway to cross the high traffic freeway, helping protect Canadian wildlife and motorists from potentially fatal collisions.

The 44 sections of precast box culvert, with a combined weight of over 2,640 tonnes, were placed in just four days, demonstrating the ease of installation of this innovative design. In 2014 this project received First Place in the Underground Category of the National Precast Concrete As-sociation’s (NPCA) Creative Use of Precast (CUP) Awards.

LEFT: PRECAST CULVERT, HIGHWAY 407ETR, WHITBY, ON


MAIN BRIDGES, HIGHWAY 30, MONTREAL, QC

THE CONFEDERATION BRIDGE, PEI/NEW BRUNSWICK: One of Canada’s top engineering achievements of the 20th century, the Confederation Bridge is a spectacular example of the important

role concrete plays in the country’s infrastructure. Photo: Shaun Lowe.

Durability and Resilience in an Uncertain World

Durability, longevity and resilience are central, but often overlooked, aspects of sustainability. A key aspect of resilience is the ability of structures to withstand extreme events such earthquakes and violent weather. Codes and standards require that structures meet minimum safety requirements. Concrete structures, by their nature, meet and exceed these code requirements and offer a level of ser-viceability over other materials that ultimately reduces the cost and environmen-tal impact of replacing (or bringing structures back into use) after a disruption.

Climate change is adding a whole new dimension to the concept of resilience for the entire network of infrastructure that underpins our quality of life. Resilient infrastructure is a first line of defense — a crucial component of broader strategies to minimize the risk to our communi-ties from the impacts of extreme weather.

Yet, according to the Federation of Canadian Municipalities, Canadian cities have an existing infrastructure deficit of $171.8 billion with urgent upgrades needed for roads and bridges ($91.1 billion), waste management systems ($39 billion) and wastewater and storm water sys-tems ($15.8 billion)1. Add to this the anticipated costs of climate change — up to 1% of Gross Domestic Product (GDP), or $5 billion per year, climbing to $43 billion per year by 20502 — and the enormity of the infrastructure challenge becomes clear.

Crisis breeds opportunity, and among the most significant opportunity that climate change presents for designers and managers of infrastructure is to help shake off the “lowest initial cost” model that continues to dominate many infrastructure decisions in an era of fiscal restraint. A holistic, Life Cycle Assessment driven analysis can help establish and promote the return on investment (ROI) for infrastructure decisions that favour durability, longevity, climate resilience and maximum value for taxpayers.

Infrastructure professionals can contribute to the climate resilience of our communities by de-signing “no regrets” resiliency into their projects. Concrete can play a role in these designs by delivering on a range of economic, social and environmental metrics that add value today while also offering a high degree of longevity and resilience for tomorrow. Winnipeg’s Alexander Av-enue, one of the oldest concrete pavements in North America with a service life of one hundred years (and counting) with little required maintenance, stands as a prime example of longevity that delivers enduring value.

Using concrete wastewater pipe to double as a source of thermal energy to heat buildings, as is being done at Vancouver’s False Creek Energy Center, is another example of this type of thinking.

Designers can include innovative materials such as ultra-high performance concretes (UHPC) — stronger, longer lasting and efficient concretes that were initially developed for the critical infrastructure sector. UHPC can bring even higher levels of durability and longevity benefits to structures.

Resilience challenges us all to think in much more integrated ways to ensure what we build today is built right, and built to last. Concrete products offer “win-win” solutions under today’s conditions of uncertainty.

INFRASTRUCTURE THAT LASTS

1 Federation of Canadian Municipalities Canadian Infrastructure Report Card, Volume 1, 2012: Municipal Roads and Water Systems 2 National Round Table on the Environment and the Economy. (2011). Paying the Price: The Economic Impacts of Climate Change for Canada


Stormwater Management in the Age of Climate Change

Water is at the heart of climate change’s impacts on communities —increased frequency and severity of droughts, floods, storm surges, and sea level rise are already being observed, and mitigating these effects is among the most urgent challenges to make our communities more resilient. A 2014 survey found that a strong majority of water experts in Canada are deeply concerned about the current capacity and condi-tion of water infrastructure across Canada, including water distribu-tion, sewage and storm water management.

Some of these challenges can be met, in part, with better management of “natu-ral” infrastructure — for example, restoration of wetlands, natural urban riverine systems and forest canopy. However, there is no escaping the critical role that pub-lic projects will play in urbanized areas. From infiltration solutions such as pervious and permeable interlocking concrete pavements, to bioswales, concrete culverts and concrete pipe infrastructure, the robustness and longevity of our underground infrastructure will play a critical role in protecting our communities and reducing the impacts of climate change.

Concrete products such as precast pipes and boxes are commonly used for sewers, storm water management and culverts. Some of the concrete infrastructure we continue to rely on today is already decades old if not older yet, demonstrating performance beyond their original expected service life. While traditional below-ground concrete infrastructure continues to show it can play a critical role, new innovations and integrative thinking are demonstrating concrete technologies can provide low cost solutions to multiple sustainability challenges at once.

RESILIENT INFRASTRUCTURE: WATER IN FOCUS

PERMEABLE INTERLOCKING CONCRETE PAVEMENT, BRYN MAUR ROAD, VICTORIA.Permeable concrete pavement offers a low impact development solution to stormwater management.


EXAMPLESTownshend, Vermont Culvert Replacement

When the town of Townshend, Vermont was hit by tropical storm Irene, the storm completely washed out one of the town’s main 4.25 meter diameter corrugated metal culverts. Understanding that climate change would increase the frequency and severity of similar storms in the future, the town sought to rebuild the culvert with resilience and life cycle costs in mind. Townshend re-placed the destroyed culvert with a new open bottom, concrete arch box culvert that spans the full width of the stream.

The new box culvert is designed to withstand future extreme flooding events, and will maintain equilibrium between the flow of sediment through the culvert and the passage of aquatic organisms. Rebuilding to these higher standards now will save lives and tax dollars in the long term. A similar steel culvert collapse on Highway 174, in Ottawa, Ontario in which a car became trapped, also led city officials to replace the culvert with concrete pipe.

RESISTANT AND DURABLE. Concrete pipes and boxes are commonly used for sewers, stormwater management and culverts.

False Creek Energy Centre, Vancouver

Precast concrete geothermal sewer pipes are being used to capture heat from wastewater and provide a secure local, in-exhaustible and carbon-free supply of heat for district energy systems. One example of this technology can be found at the False Creek Energy Centre in Vancouver.

The system supplies 70% of total heating for approximately 250,000 m2 of space, avoids about 70% of GHGs in comparison to traditional heating, and is self-funded, providing a return on investment for Vancouver taxpayers. More than that, the utility provides a shared infrastructure platform that offers price stability, scalability and adapt-ability to other sources of renewable low-carbon energy. It’s a great example of how to create resilient neighbourhoods and communities that can weather, and quickly recover from, extreme events while of-fering huge sustainability benefits today. For more information see: www.greenenergyfutures.ca/blog/waste-heat-how-vancouver-mined-its-sewage-heat-entire-neighbourhood

FALSE CREEK ENERGY CENTER, VANCOUVER: Precast concrete geothermal sewer pipes contribute to False Creek Energy Center’s resilient infrastructure platform.


The MIT Concrete Sustainability Hub is an interdisciplinary team of MIT sci-ence, engineering and economics researchers focused on three core areas of concrete innovation to achieve more durable and sustainable homes, buildings, and infrastructure in ever more demanding environments.

• Materials Science: modeling techniques, starting at the atomic level, to predict structures and properties that will improve how cement and con-crete are designed, reduce CO2 emissions, and enable North American leadership in future cement technologies.

• Buildings & Pavements: innovative solutions for concrete engineering applications in buildings and pavements. For buildings, research focuses on durability, energy efficiency, and resiliency. For pavements, research focuses on improving structure and design that can result in increased fuel efficiency and lower maintenance costs.

• Economics & Environment: improved life cycle assessment and life cycle cost analysis techniques to help stakeholders wisely use limited funding for infrastructure projects while considering environmental impacts.

RESEARCH IN THE SPOTLIGHT

GOLDEN EARS BRIDGE, VANCOUVER, BC

The Athena Sustainable Materials Institute

The Athena Sustainable Materials Institute is a non-profit research collabora-tive bringing life cycle assessment to the construction sector. It recently intro-duced the Athena Impact Estimator for Highways, a free LCA-based software package that provides environmental LCA results for Canadian regional mate-rials manufacturing, roadway construction and maintenance life cycle stages. It allows custom roadway design, or users can draw from a library of 50 existing roadway designs. The software allows for quick and easy comparison of multiple design options over a range of expected roadway lifespans. The tool can be downloaded for free at: http://www.athenasmi.org. In early 2015, a web application of this tool will also be available at www.greenpav.com.

University of Waterloo Centre for Pavement and Transportation Technology (CPATT)

The Centre for Pavement and Transportation Technology (CPATT) conducts advanced research and education in the area of sustainable long-life concrete pavement. The results of the research have driven several positive changes to Canadian standards and specifications, including Pervious Concrete and Recycled Concrete Aggregate Guidelines, as well as the Transportation Associa-tion of Canada (TAC) - Pavement Asset Design and Management Guide. CPATT areas of research include:

• Use of recycled concrete aggregate (RCA) in concrete pavement • Use of recycled concrete aggregate in Structural Concrete • Concrete Overlays Performance • Pavement noise testing • Instrumentation of concrete pavements • Surface Characteristics of Next Generation Concrete Pavements

CPATT reports are available at https://uwaterloo.ca/centre-pavement-transportation-technology/

The basic recipes for cement and concrete were first discovered thousands of years ago, but the industry is still finding ways to innovate. From dissecting the chemistry of cement and concrete at the atomic level to preserving biodiversity at quarry sites, the industry has a deep commitment to research and innova-tion. Increasing product sustainability and innovating solutions to sustainability challenges in the built environment are at the heart of this commitment.

MIT Concrete Sustainability Hub


SHAWNESSY LIGHT RAIL TUNNEL STATION, CALGARY: Calgary’s Shawnessy’s Light Rail Station incorporates ultra-high-performance concrete, which permits the construction of exceptionally light, strong, and durable structures using less concrete. Photo: Vic Tucker.

BOTTOM: PERVIOUS CONCRETE. Like permeable interlocking concrete pavement, pervious concrete offers a low impact development solution to stormwater management.

Ultra-High Performance Concrete

Ultra-high-performance concrete (UHPC) is on the leading edge of concrete innovation, permitting the construction of exceptionally light, strong, durable and long service-life structures using less concrete more efficiently. One of the key applications for UHPC is for critical infrastruc-ture, where long-service life in increasingly harsh environments is desired. Reinforced with high-carbon metallic fibers, structural UHPC products can achieve compressive strengths up to 200 MPa and flexural strengths up to 20 MPa. For architectural UHPC applications, Polyvinyl Alcohol (PVA) fibers are used. Due to the material’s superior compressive and flexural proper-ties, the need for passive reinforcing can be eliminated or greatly reduced (depending on the application). It is also highly moldable and repli-cates form materials with extreme precision, allowing for thin, complex shapes, curvatures and customized textures not possible with traditional reinforced concrete.The advantages of UHPC are numerous and typically include reduced global costs such as formwork, labor, maintenance and speed of construction.

Pervious and Permeable Interlocking Concrete Pavements

Urban development alters the natural landscape of our communities, creating hardscape surfaces that prevent infiltration of water into soil surfaces and increasing runoff. Stormwater runoff can send as much as 90% of pollutants, such as oil and other hydrocarbon liquids found on the surface of traditional parking lots, directly into rivers and streams. By capturing rainfall and allowing it to percolate into the ground, soil chem-istry and biology can treat the polluted water naturally. It can also play an important role in flood mitigation in urban environments. Permeable interlocking concrete paving systems (PICP) and pervious concrete pave-ments (PCP) both offer a low-impact development (LID) solution to restore the natural ability of an urban site to absorb stormwater.

PRODUCT INNOVATION IN ACTION


Today, the sustainable movement has two new words to get acquainted with, words that may be even more important since they affect not just construction but the very quality of life in our communities: depollution and photocatalysis. Photocatalysts keep concrete clean and depollute the air we breathe. Important new concepts often require new words to convey their meanings.

THE I-35 GATEWAY MONUMENTS, MINNESOTA. Built using photocatalytic concrete.

Photocatalytic Concrete

Here is how it works. Strong sunlight or ultraviolet light decomposes many organic materials in a slow, natural process. Photocatalysts accelerate this process and, like other types of catalysts, stimulate a chemical transformation without being consumed or worn out by the reaction. When used on or in a concrete structure, photocatalysts decompose organic materials such as dirt, including; biological organisms, mold, bacteria; airborne pollutants, including volatile organic compounds, and the nitrous oxides [NOx] and sulfuric oxides [SOx] that are significant factors in smog. Plus it’s self cleaning (based on particles of titanium dioxide).

In Canada, the Ontario Ministry of Transportation is conducting a pilot project with a section of noise barrier on Highway 401, and will compare results against test benchmarks achieved in other countries.


30, RUE VICTORIA, GATINEAU. This was among the first buildings in Eastern Canada to be constructed using Contempra-based concrete.

Cement is the “glue” that makes up, on average, 10-15% by weight of concrete. As such, it plays an important role in the construction of durable resilient structures worldwide. While cement contributes as little as 3% to a building’s total lifecycle greenhouse gas emissions (GHGs), (see the Athena Materials Institute study discussed on page 7), the cement industry recognizes the importance of sustainable stewardship to minimize its environmental impacts, particularly the need to reduce manufacturing GHGs.

The cement industry’s commitment to reducing GHGs extends back at least two decades when it made major capital investments in new energy efficiency technologies, such as waste heat recovery through pre-heater towers. Today, the industry’s two primary strategies for reducing CO2 are to a) substitute fossil fuels with low carbon and renewable fuels; and, b) reduce the amount of clinker required in cement and the amount of cement required in concrete. The second strategy is where architects, engineers and planners can play an important role in reducing the embodied CO2 of their projects by specifying low clinker cement as well as mix designs that maximize cement sub-stitution in accordance with required performance specifications. In fact, cement substitution with by-products of other industrial processes (e.g. fly ash, slag and silica fume) can significantly reduce embodied CO2 while also diverting waste from landfill. Three years ago, the cement industry intro-duced to the Canadian market a product called Contempra (referenced in the National Building Code under the name of Portland-limestone cement). Contempra reduces CO2 emissions by 10% - 12%, while producing concrete with an equivalent level of strength and durability to concrete produced with regular Portland cement. There are many technologies coming on stream that hold promise for even more dramatic reductions. Carbon capture, reuse and storage technologies are still evolving, but they suggest that carbon neutral cement is both technologically feasible and a likely potential in the future of the industry.

CEMENT MANUFACTURING AND GHGs


Reducing GHGs with Contempra

In 2011, the Canadian cement industry introduced ContempraTM, a new cement that reduces CO2 emissions by 10% while still producing concrete with the same level of strength and durability as concrete produced with regular Portland cement. This is achieved by intergrinding regular clinker (the main ingredient in cement) with up to 15% limestone, which is 10% more than in regular Portland cement. Reducing the clinker content of cement in this way reduces the amount of emissions associated with its manufacturing.

Today, Contempra is rapidly becoming the preferred standard for the majority of new concrete construction projects in Canada . In British Co-lumbia alone, it accounted for nearly 50 per cent of the domestic cement consumed in the province in 2013. This uptake will accelerate as more and more developers and builders specify the carbon-reduced cement for their new projects, leading to potential GHG reductions of up to 900,000 tonnes annually.

Among the many Contempra projects completed or underway in Canada are the Trump Tower and the Wall Center False Creek Development, both in Vancouver; the Lansdowne Park redevelopment project in Ottawa; the McGill University Health Centre (MUHC) and the Centre hospitalier universitaire Sainte Justine in Montreal; and a multitude of condominium, commercial and institutional projects throughout the country.

Other innovations, such a carbonated concrete (concrete that is cured with CO2 instead of, or in addition to, water) and the use of novel biogenic fuel sources (e.g. algae grown with flu gas) are quickly evolving and showing tremendous promise for a future of low-carbon concrete. Technologies nearing the commercialization phases today may soon reduce cement CO2 emissions by up to 70%.

BACK COVER: PORT MANN BRIDGE, VANCOUVER, BC

THE TRUMP TOWER, VANCOUVER: Built using lower carbon Contempra-based concrete, the Arthur Erickson-designed twisting Trump tower will stand at 63 storeys in downtown Vancouver. Photo: Trump International Hotel & Tower, Vancouver.


APPLICATION INDUSTRY ASSOCIATION WEBSITE

Cement manufacturing Cement Association of Canada www.cement.ca

Architectural and Structural Canadian Precast/Prestressed Concrete Institute www.cpci.caPrecast and Prestressed Concrete Components

Cast-in-place concrete Canadian Ready Mixed Concrete Association www.crmca.ca

Provincial Ready Mixed Concrete Associations

Association Béton Quebec www.betonabq.org Atlantic Concrete Association www.atlanticconcrete.ca

Ready Mixed Concrete Association of Ontario www.rmcao.org

Manitoba Ready Mix Concrete Association www.mrmca.com Saskatchewan Ready Mixed Concrete Association www.concreteworksharder.com

Alberta Ready-Mixed Concrete Association www.armca.ca

BC Ready-Mixed Concrete Association www.bcrmca.ca

Concrete pavements Canadian Ready Mixed Concrete Association www.crmca.ca Canadian Precast/Prestressed Concrete Institute www.cpci.ca Cement Association of Canada www.cement.ca

Provincial Ready Mixed Concrete Associations see cast-in-place concrete Interlocking Concrete Pavement Institute www.icpi.org

Concrete pipe Canadian Concrete Pipe and Precast Association www.ccpa.com Tubecon (Quebec) tubecon.qc.ca

Insulated Concrete Forms Canadian Ready Mixed Concrete Association www.crmca.ca

Interlocking concrete pavement Interlocking Concrete Pavement Institute www.icpi.org

Masonry Canadian Concrete Masonry Producers Association www.ccmpa.ca

Pervious and permeable Canadian Ready Mixed Concrete Association www.crmca.cainterlocking concrete pavements Provincial Ready Mixed Concrete Associations see cast-in-place

Interlocking Concrete Pavement Institute www.icpi.org

From the foundation of our homes to our skyscrapers, from our community centers to our bridges, transit ways, and other infrastructure installations − such as dams and water treatment plants − that are essential to our society’s ability to function efficiently, we rely on concrete every day.

Whether it is precast concrete, cast-in-place concrete, insulating concrete forms, masonry, concrete pipe, or ready-mixed concrete, we use concrete in so many ways and in so many different types of construction and infrastructure. Each of these applications shares concrete’s fundamental sustainability attributes.

Canadian cement companies and a great many independent producers of concrete in its many forms are active in industry associations that aim to advance knowledge of concrete. In 2013, these associations came together to form the Concrete Council of Canada. They can be found on rediscoverconcrete.ca, a cement and concrete industry portal that provides comprehensive informa-tion on the sustainability of concrete and the activities of the Concrete Council of Canada.

CONCRETE INDUSTRY RESOURCES

IRVINE RIVER BRIDGE, ELORA, ON

rediscover concrete...for a sustainable transportation infrastructure. from high performance green...

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