Oct 04, 2006

Opting for the Sustainable

Specifications for reconstruction work on sections of Highway 40 in the province of Québec, Canada, and recent policy announcements by the province’s Transportation Ministry demonstrate that Québec has opted for sustainable highway infrastructure. The portion of Highway 40 from the Ontario border to the Highway 25 interchange is part of the Trans-Canada Highway, established in 1959 as a city and rural highway system.

The Highway 40 Phase III project was one of the major reconstruction projects undertaken by the Ministère des Transports du Québec (MTQ) in 2005. The project was located between Des Sources Blvd. in Dorval and Saint-Charles Blvd. in Kirkland, west of Montréal on the north shore of the Saint Lawrence River. It consisted of 6.1 km of pavement, with a concrete pipe storm sewer system. Continuous reinforced concrete pavement (CRCP) was chosen as the surface pavement, because the previous two phases were comprised of CRCP. The storm sewer system consisted of 3.5 km of 250-mm-diam. Class III reinforced concrete pipe (RCP) and 800 meters of 450-mm-diam. Class III RCP. The 450-mm-diam. RCP was used for the main line and the 250-mm-diam. pipe was used for interconnecting catch basins. To simplify the installation, a uniform diameter of 250 mm was chosen as the smallest diameter for that job. To connect the main storm sewer line to the catch basins, 96 special fittings had to be manufactured.

All pipe and catch basins were produced according to Québec Bureau of Normalization (BNQ) standards, and all products were certified by the BNQ according to the publicly accessible certification protocol NQ2622-951. That certification system is a third party managed by the BNQ, which is also accredited by the Canadian Standardization Council to certify infrastructure products.

Made to fit

A special aspect of the project was that the catch basins had to be installed at precise locations to accommodate the drainage layout for the concrete pavement. That meant that extensive pipe cutting was required to adjust RCP connections to every catch basin. The 96 special fittings also had to be custom made to fit precisely.

According to Jean-François Gauthier, engineer and coordinator of the civil engineering component, the precision connections to all the catch basins did make the installation more complex than usual. The overall job using RCP went well and on schedule. Inspectors found the concrete pipe installations easy to check. Miceli et Frères supplied all of the 1,600 pipes and fittings that were needed for the project. Pipe and fittings were delivered onsite within a 40-day schedule.

Phase IV of the project was contracted to Les Grands Travaux Soter Inc. (GTS) of Laval, Québec, in February 2006. The tender documents comply with MTQ’s culvert and storm sewer construction specifications policy and calls for over 3.5 km of 250-mm-diam. Class III RCP and 1.22 km of 450-mm-diam. Class III RCP supplied by Miceli et Frères. The project is essentially an eastward continuation of Phase III.

Funding for the Highway 40 reconstruction maintenance project was authorized in August 2003 under Canada’s Strategic Highway Infrastructure Program, which was established to invest some $217 million (CAD) in Québec’s highway system between 2003 and 2006. The program funded nine projects in five regions in Québec to increase traffic capacity and enhance motorists’ safety.

Pipe policy

New policy for installing pipe under Québec highways was introduced during construction of the Phase III project. The policy was a result of a lengthy review of the culvert and storm sewer construction specifications of the MTQ. These documents, entitled Tome III—Ouvrages d’art and Tome II—Construction routière, are part of the seven books of standards published by the MTQ.

In essence, the policy states that reinforced concrete pipe will be the only circular pipe allowed for culverts and storm sewers under highways. Reasons such as durability and reliability seem to have justified this choice. Culverts under highways must last a minimum of 75 years and storm sewers must last at least 50 years. This policy complements the use of CRCP on major highways, since the performance and service life of reinforced concrete pipe is more closely aligned to the performance and service life of CRCP and other forms of concrete pavement than alternate pavement materials.

CRCP is a cement-concrete pavement characterized by continuous steel reinforcement set into the concrete and the omission of transverse joints other than construction and terminal joints. CRCP slabs are widely used in the U.S. and some European countries. The U.S. first used this concrete pavement in 1921.

Today, over 50,000 km of highway lanes have been built in CRCP. The slabs have the advantage of requiring little or no maintenance and long service life. They are used for rural and urban highways in which there is high-volume traffic, including trucks. Québec is one of the provinces with the greatest number of kilometers of exposed concrete highways in Canada. The use of CRCP on Highway 40 is consistent with the province’s history of concrete pavements on major highways.

Québec’s policy decision also is consistent with recent research findings in the U.S. that strongly suggest that concrete pipe culverts on major roadways contribute significantly to the service life of transportation networks. By matching the service life of the highway drainage systems with the design life of the highways, current and future generations of taxpayers will realize significant savings found in lower maintenance and non-concrete pipe culvert replacement costs due to premature replacements or pavement failures.

Risk of failure

In 2004, Dr. Joseph Perrin Jr. of the University of Utah reported on a study of the economic cost of culvert failures. The scope of his research was to quantify the economic implications of culvert failures—including related highway user-delay costs—to find out if the risk of failures is being considered as a culvert material selection criteria and to identify the need to document culvert failures. He argued that user-traffic-delay costs cannot be overlooked when considering life-cycle cost analyses of culverts. Most often, user-delay costs far exceed the actual construction costs.

Any initial savings that occur by installing a culvert material with a lower service life expectancy is quickly exceeded by subsequent replacement installations and user delays. By quantifying the additional costs of emergency replacement, it is clear that an inspection and maintenance program provides an attractive cost benefit. It also shows that culvert materials with a longer service life are more cost-effective than materials with lower service life expectancy—even if initial installation is more expensive.

The 50th anniversary of the federal law that brought America its interstate highway system is being celebrated through 2006. On June 29, 1956, President Dwight Eisenhower signed the Federal Aid Highway Act of 1956 into law, beginning one of the biggest engineering projects ever undertaken. Many of the nation’s highway culverts have been failing over the past 10 to 15 years, as their service lives ended before they could be replaced. There were few culvert replacement and maintenance programs considered when the interstate highways were built, and now taxpayers are faced with significant unexpected replacement costs, including the cost of delays and detours.

Québec’s highway and roads system totals 28,965 km, and 19% are highways. There are 60,000 culvert structures. If they were to be joined end to end, these structures would extend approximately 1,300 km. The MTQ also owns storm sewer systems, but their numbers are not compiled.

On Sept. 14, 2005, a 7.6-meter span x 5-meter rise elliptical metal structure collapsed and caused the closing of Highway 40 in Québec near Trois-Rivières. Excavation of connecting pipes caused a loss of soil structure and the collapse of the elliptical pipe. Two lines of circular reinforced concrete pipe, 3,000 mm in diam., installed in parallel lines replaced the failed metal elliptical pipe structure. The Highway 40 culvert failure occurred at the time that policy was being introduced specifying reinforced concrete pipe for culverts and storm sewers under highways. The large-diameter concrete pipe culvert is now an integral component of the highway infrastructure designed to last for decades.

The province of Québec is planning and implementing strategies that should have a positive impact on its major highway systems and taxpayers far into the future. The service life of reinforced concrete pipe used for storm sewers and culverts has proven durability that can exceed 100 years. Québec’s highway infrastructure is a sustainable system that takes into consideration construction materials, while matching service life of products with design life of projects. The province’s policy for installing pipe under Québec highways is both timely and progressive.

About the author

Miceli is an engineer for Miceli et Frères. He can be reached at 450/474-6189.

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