InfraStructures - November 2008 - Longitudinal Joint Heating Makes a Good Joint

Longitudinal Joint Heating Makes a Good Joint

A presentation on asphalt longitudinal joints given by Rob McClure P. Eng. of Hatch, Mott, Macdonald at this past Swift Airport Conference in Calgary has demonstrated success of longitudinal joint heating as a means of making a well constructed joint. The presentation was an outline of the problems of construction of a durable longitudinal joint, and used a case study of a paving project done by Lafarge Construction, in 2007, at the DFC Shearwater Heliport in Dartmouth, Nova Scotia.

The speciÞcations required cutting and removal of the edge of the cold lane prior to butting up the new hot lane. Lafarge requested approval on an alternate using a longitudinal joint heater, the HDE JMH 400T, manufactured by Heat Design Equipment Inc. (HDE) of Kitchener, Ontario. This alternate was approved and the results well documented.

The joint heating proved very effective, saving Lafarge money in material, labor, and project time. All the test results using the joint heater met the required compaction, whereas the cut joints had failures. The appearance of the joint was very good. The cost was reported to be in the area of $0,15 per lineal meter, which is considerably under any other longitudinal joint construction technique cost, even considerably under any joint repair technique. The infrared heating equipment used, was able to reheat the cold joint at paving speeds without overheating the asphalt pavement. The 2008 project speciÞcations were changed to include joint heating.

Heat Design Equipment Inc. has been promoting the idea of a re-heated joint since 1995, and have been supplying their patented heating equipment to meet a hot joint speciÞcation in the Province of Quebec since then. Over the years, they have been on numerous projects, both in Canada and the United States, but this project could be considered the best documented.

One of HDE's early test projects for the Ministry of Transport of Ontario was in 1997 on the QEW, where after 11 years "these longitudinal joints continue to perform well." according to Ontario's Minister of Transport the Hon. Jim Bradley.

The idea of a hot joint is nothing new, and echelon paving is recognized as the best way to achieve a good longitudinal joint. Robert Kieswetter P. Eng, CEO of HDE likes to think that joint heating is the next best thing, and "it is, providing it can be done efÞciently, without overheating the asphalt." HDE has done this now in Quebec, Ontario, Tennessee, Michigan, Nova Scotia and Washington DC (at the White House*) on real projects. The Shearwater report is a documented testimony to this.

HDE introduced a new light weight paver attached model, the HDE JMH 300PA at ConExpo-Con/AGg 2008, and will show an improved model at the upcoming World of Asphalt 2009 in Orlando, Florida, March 9-12, 2009. This model was built to accommodate tighter paving conditions for new hot joint speciÞcations by municipalities who are realizing the value a heated joint.

The Shearwater report and HDE product information can be viewed on the HDE website www.asphaltheater.com.

Source: Heat Design Equipment, Inc.