SBIR-STTR Award

This Small Business Innovative Research Phase I project will demonstrate an in situ process control device, based on nuclear magnetic resonance (NMR), for the analysis of asphalt pavement used in the highway industry. This proposal is based on the work the Principal Investigator did under contracts from the Strategic Highway Research Program. That work showed how NMR can be used to measure the physical properties of neat asphalt and the concentration of asphalt/aggregate mixes including cores. This research will attempt to extend this technique to the measurement and study of the reaction that occurs between asphalt and aggregate when they are mixed. The study of this reaction plus the development of NMR methods to measure the physical properties of the asphalt in situ in a mix or core will allow the design and the construction of a flat magnet NMR system that will determine the amount and physical condition of asphalt pavements, in-place, on a roadbed. The device developed in this overall project can be used in a number of closely related applications in the highway industry. The determination of the amount of asphalt in mixes and cores is an application that could result in sales of several hundred units in the United States alone. The use of a flat magnet system for in situ analysis of asphalt in pavement could also have a profound impact on pavement maintenance.

This Small Business Innovation Research Phase II project will develop and test nuclear magnetic resonance (nmr) based process control devices for asphalt-aggregate mixes. The Phase I research demonstrated how hardware improvements, including a shim system for a Halbach dipole magnet, makes laboratory and on-line instrumentation possible. The laboratory unit will be able to measure asphalt physical properties in neat asphalt in mixes over a wide range of temperatures. The on-line unit will lead to asphalt process control in a hot mix plant and at paving sites. An in situ device will be designed and tested on in-place pavement. Previous work by the firm demonstrated how asphalt physical properties change when mixed with aggregate and how these changes can be measured with nmr to determine what is defined as "free asphalt" in a mix. This free asphalt probably has an important impact on pavement physical and use properties. This could eventually lead to the development of instrumentation that can measure the amount and physical properties of asphalt in pavements without removing a sample from the pavement. Commercial applications for this technology exist in asphalt laboratories, hot mix plants and in-place pavements. Applications also exist in food processing.