ASPHALTopics | Spring 2014 | VOL 27 | NO 1

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CONTINUED FROM PAGE 29 With the price of the additives and the possibility of plant retrofits to accommodate the warm mix process, MTO admits there are higher costs involved with WMA, but for now will let contractors decide the extent of its use unless otherwise specified. Ultimately, the key for MTO is to ensure the best practices are in place to make sure roads are safe, environmentally friendly, soundly constructed, long lasting, and created without major disruptions to drivers — all at a price beneficial to taxpayers. “We have to look after everyone’s best interest,” says Pamela Marks, Head, Bituminous Section, MTO. Marks says the Ministry has to weigh all of the factors in determining the future of warm mix. And while positive results have been reported in all sectors, MTO is not going to force the use of the technology. “We are allowing it to be a tool in a contractor’s tool box, something they can use to help them in their process,” says Marks, adding that the technology is evolving and MTO has to look at all aspects that may benefit the infrastructure of the province. OHMPA’s 40 th Anniversary Annual General Meeting Westin Trillium House Blue Mountain, Collingwood March 26 th Reception, President’s Dinner and Auction for Asphalt Research & Advocacy March <strong>27</strong> th – AGM To download the registration brochure for full details, go to OHMPA’s website www.ohmpa.org 30 OHMPA | ASPHALTOPICS
TECHNICALLY SPEAKING by Sandy Brown OHMPA Technical Director Potholes – fact and fiction Thanks to the polar vortex, pothole season arrived a little early this year. As a result, this winter there has been a lot of talk in the media about potholes and whether there could be a cure for what ails the roadways. The reality is that there is no panacea for potholes. Potholes typically occur five to seven years after the road is paved and are the result of water that gets into the pavement. When the ground freezes, so does the water, causing expansion. Repeated freezing and thawing of the water in the pavement structure weakens the surfacing to the point where the weight of passing vehicles begins to break up the pavement matrix and a pothole is born. The key to pothole prevention is to build a durable road with good drainage, adequate pavement thickness, and tight longitudinal joints. You also need to properly maintain the road by sealing the cracks and the longitudinal joints. If water doesn’t get to the pavement in the first place, the pothole problem is resolved. There has also been a lot of talk about the quality of the asphalt cement in Ontario with references in the media to “garbage asphalt”. Nothing could be further from the truth. All asphalt cement used by Ontario municipalities meets OPSS.MUNI 1101 specifications and this specification is under constant development. MTO and industry formed a Binder Task Group in 2006 to look at improving the performance of asphalt cement used in Ontario. Initially the group looked at low temperature performance, but the scope has broadened to include other aspects. The municipal specification is revised regularly and the latest revision, issued in November of 2013, is based on work by the Task Group. The specification incorporates two new test procedures. The first limits the use of polyphosphoric acid (PPA) and the second limits the use Re-refined Heavy Vacuum Distillate Oil (RHVDO) residue. However, there is no municipal specification in Ontario for the use of polymers, and in particular elastomeric polymers, in asphalt cement. Polymer modification was introduced in North America in the 1970s, but it wasn’t until we started to specify asphalt cement using Superpave Performance Grading (PGAC) in the late 1990s that polymer use became more prevalent. PGAC grading requires the asphalt cement to perform over a wider range of temperature reflecting different traffic and environmental conditions. There is no “new asphalt” as has been referenced in the media. Higher performance asphalt cements have been available in Ontario for municipal use since the adoption of the Superpave specification, but they are seldom asked for because there is an increase in cost. These materials are available and specified in OPSS.MUNI 1101 under what is called grade bumping. While typically only used on higher traffic roads, products such as PGAC 70-28 have been available for over 10 years and can be specified on any project. The MTO and Industry Binder Task Group have been studying new test procedures for asphalt cement for the last seven years. Two different test procedures have been reviewed: The Double Edge Notched Tension (DENT) test (using equipment originally introduced in 1910), and a newer procedure developed in the United States called ›› CONTINUES ON PAGE 36 SPRING <strong>2014</strong> 31
Page 1: SPRING 2014 | VOL27 | NO1 Paving In
Page 4 and 5: 30 Years
Page 6 and 7: WE KNOW THE ROAD. WE’VE BEEN ON I
Page 8 and 9: 8 OHMPA | ASPHALTOPICS
Page 10 and 11: Meet incoming OHMPA president Bentl
Page 12 and 13: New Indy road course a winning form
Page 14 and 15: Russell Redi-Mix Concrete, Manitoba
Page 16 and 17: y Steve Pecar Trillium Awards While
Page 18 and 19: AWARDS From left to right: John Bla
Page 20 and 21: WE DARE TO BE DIFFERENT, SO YOU CAN
Page 22 and 23: Only Astec has the patented Double
Page 24 and 25: CONTINUED FROM PAGE 21 Even if brid
Page 26 and 27: Warm mix comes of age by Steve Peca
Page 28 and 29: Albarrie’s Door Seals & Dryer/Dru
Page 32 and 33: Crushing and fractionation of a bul
Page 34 and 35: Exclusive Canadian Distributor Gyra
Page 36 and 37: CONTINUED FROM PAGE 31 the Percent
Page 38 and 39: ENVIRONMENTAL ESSENTIALS by Corey K
Page 40 and 41: INDUSTRY NEWS OGRA/ROMA TRADESHOW I
Page 42 and 43: THE LAST WORD by Pamela Marks When
Page 44: GOING THE EXTRA MILE From manufactu

ASPHALTopics | Spring 2014 | VOL 27 | NO 1

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