Electric field probes for quantitative moisture measurements in building materials
Courville, G. E., Hylton, J. O., Murray, W. P., Blalock, A., and Remenyik, C. J.
1996
Water Vapor Transmission Through Building Materials and System: Mechanisms and Measurement, ASTM STP 1039, H. R. Trechsel and M. Bomberg, Eds., American Society for Testing and Materials, Phila-delphia, pp. 101-113
moisture sensors, capacitance, moisture measurements, electric field probes, building materials, moisture, dalibration, water vapor transmission, testing
Courville, G. E., Hylton, J. O., Murray, W. P., Blalock, A., and Remenyik, C. J., (1996), "Electric field probes for quantitative moisture measurements in building materials", Water Vapor Transmission Through Building Materials and System: Mechanisms and Measurement, ASTM STP 1039, H. R. Trechsel and M. Bomberg, Eds., American Society for Testing and Materials, Phila-delphia, pp. 101-113.
| Abstract: |
| Three novel capacitance techniques for making moisture measurements in in-sulated roof systems are being studied at the Oak Ridge National Laboratory (ORNL). These are designated as the Pin Probe, the Thermocouple Probe, and the Planar Probe. The Pin Probe, developed at the Massachusetts Institute of Technology (MIT), consists of two parallel lines of straight pins as the two probe electrodes. This is an intrusive probe that must be mounted within the system being tested. The Thermocouple Probe is also intrusive. Its use assumes that thermocouple junctions exist at known locations in the specimen for temperature measurements. The probe electronics allows high-frequency impedance measurements between thermocouples without interfering with their temperature measurement function. The third probe, the Planar Probc, is nonintrusive and consists of a series of equally spaced plate electrodes in a box that sits on the surface of the roof. These electrodes provide several independent electrical signals from overlapping depths within the roof system. An analysis procedure was developed to identify the electrical properties of successively deeper layers of material.
Prototypes of each of these probes have been constructed and promising preliminary data are available. Probe calibration, circuit stability, and range of applicability are major out-standing issues that must still be addressed.
Appears in Trechsel, H. R. and Bomberg, M., (Eds), 1996, Water vapor transmission through building materials and system: mechanisms and measurement |
|
|
|
Related Concepts
|
Related Resources:
 ASTM
"provides a global forum for the development and publication of voluntary consensus standards for materials, products, systems, and services"
- IRC: Institute for Research in Construction
"Canada's research, building code development, and materials evaluation services, .. issues that have a large economic impact, assisting industry to innovate and develop technologies that are safe, durable and cost-effective. "
|