Construction for Test Track Fifth Cycle Underway

Pressure cell installation on the NCAT Pavement Test TrackSponsored sections for the 2012-2015 Pavement Test Track (fifth) cycle are in various stages of construction. Some sections from the previous cycle are simply remaining in place for further testing, while many new sections are being instrumented to measure pavement responses to heavy trafficking and paved with special mix designs.

Construction has already included installation of earth pressure cells, which will provide vertical stress readings as the trucks pass over the pavement surface. These measurements can be linked to pavement performance metrics such as rutting and provide valuable data for mechanistic model development. The installation procedure is intended to install the earth pressure cell with as little disruption as possible and to protect the gauge from the further pavement construction.  A shallow cavity is first excavated and a cable trench is cut to position the gauge flush to the subgrade surface while protecting the cable below the surface.  Fine sieved material is used to level the gauge and protect it from large stones.  The gauge is then covered with native material,  which is re-compacted. 

Futher instrumentation will occur later this summer, including strain gauge installation in various sections. Paving occurs each week at different times depending on the weather and other factors.