This report describes four new instrumented test road sections that have been built on E45 close to the Svappavaara in Norrbotten County in Northern Sweden. The structures are located about 100 km north of the Arctic Circle in a climate that is characterized by long cold winters and short mild summers. Norrbotten County is a sparsely populated area where the pavement structures consist of thin pavements with relatively low traffic volume. A new ore deposit, the Kaunisvaara project, was opened in 2012, meaning that the ore will be transported along the existing road network about 160 kilometers to where it will be transferred to a railway. The ore operator has received a permit to use 90 ton vehicles instead of the permissible 60 tons, consisting of a single wheel steering axle and triple dual wheel tridem axles to transport the iron ore. When the ore processing will be in full operation around 66.000 journeys per year will pass over the network, or on average about 7—8 passes per hour with about seven and a half minutes between the passes. Due to this new ore transport it will be necessary to strengthen the local road network. As part of the process to evaluate the performance of a suitable pavement structure these four instrumented test road structures have been selected and built. The structures are instrumented with road performance and climate sensors. The structures will be monitored over the years to come, though the details of the monitoring programme have not yet been decided. Each test section is around 200 metres long, consisting of a 100 metres long inner part that constitutes the intrinsic test section. The structures were built and instrumented in the summer of 2012 except for the wearing course that was placed in the summer of 2013 along with the temperature sensors that are placed in the asphalt layers. The instrumentation in each section consists of Emu coils for vertical strain measurement devices, soil pressure cells for vertical stress measurements and tensile strain gauges located at the bottom of the bound road base layer. In addition there are moisture rods located in three of the structures and a temperature (frost) rod located in structure 3. A weather station (2527 Svappavaara) operated by the Transport Administration is located 3.2 kilometre south-east of the test site. (Author/publisher)
Samenvatting