Cone penetrometer deployed in situ video microscope for characterizing sub-surface soil properties
- Naval Command, San Diego, CA (United States)
- San Diego State Univ. Foundation, CA (United States); and others
In this paper we report on the development and field testing of an in situ video microscope that has been integrated with a cone penetrometer probe in order to provide a real-time method for characterizing subsurface soil properties. The video microscope system consists of a miniature CCD color camera system coupled with an appropriate magnification and focusing optics to provide a field of view with a coverage of approximately 20 mm. The camera/optic system is mounted in a cone penetrometer probe so that the camera views the soil that is in contact with a sapphire window mounted on the side of the probe. The soil outside the window is illuminated by diffuse light provided through the window by an optical fiber illumination system connected to a white light source at the surface. The video signal from the camera is returned to the surface where it can be displayed in real-time on a video monitor, recorded on a video cassette recorder (VCR), and/or captured digitally with a frame grabber installed in a microcomputer system. In its highest resolution configuration, the in situ camera system has demonstrated a capability to resolve particle sizes as small as 10 {mu}m. By using other lens systems to increase the magnification factor, smaller particles could be resolved, however, the field of view would be reduced. Initial field tests have demonstrated the ability of the camera system to provide real-time qualitative characterization of soil particle sizes. In situ video images also reveal information on porosity of the soil matrix and the presence of water in the saturated zone. Current efforts are focused on the development of automated imaging processing techniques as a means of extracting quantitative information on soil particle size distributions. Data will be presented that compares data derived from digital images with conventional sieve/hydrometer analyses.
- OSTI ID:
- 613791
- Report Number(s):
- CONF-970113-; TRN: 98:001739-0041
- Resource Relation:
- Conference: Field analytical methods for hazardous wastes and toxic chemicals conference, Las Vegas, NV (United States), 29-31 Jan 1997; Other Information: PBD: 1997; Related Information: Is Part Of Field analytical methods for hazardous wastes and toxic chemicals; PB: 909 p.
- Country of Publication:
- United States
- Language:
- English
Similar Records
Subsurface screening of petroleum hydrocarbons in soils via laser induced fluorometry over optical fibers with a cone penetrometer system. (Reannouncement with new availability information). Professional paper
Non-invasive Technology to Study Local Passivity Breakdown of Metal Alloys in Aqueous Media