Geotechnical

Standalone Measurement Instrumentation

Geotechnical

Campbell Scientific stand-alone data acquisition systems are versatile, rugged, and powerful—factors that make them ideal for geotechnical applications. Our systems can monitor tilt, convergence, displacement, geographic position (GPS receivers), strain, load, vibration, overburden, level, flow, creep, and force to name a few. As such, our systems are used in a variety of geotechnical applications including slope stability, subsidence, seismicity studies, structural restoration or mitigation, and site assesment. Our systems can measure a variety of sensor types used in geotechnical applications including voltage output, vibrating wires, pulse output, SDI-12, resistive bridge, etc. It is also common to measure meteorological and hydrological parameters in the same system to determine cause-and-effect relationships.

System Benefits

  1. Systems measure most commercially available sensors—analog, resistive bridge, vibrating wire, 4-20 mA, SDI-12, etc.
  2. Systems used in geotechnical and various mining applications include: slope stability, roof control, methane monitoring, air and water quality, and equipment monitoring/performance.
  3. Systems not only measure but control external devices, based on time or measurements.
  4. Wireless and hardwire communication options provide real-time reporting.
  5. Low unit costs and networking capability allow placement wherever measurements are needed.
  6. PC software supports data retrieval, data display, data logger programming, and override control capability.
  7. Low current drain allows operation from batteries and solar panels.

Data Acquisition

The versatility of our systems allows them to be customised for each application. We offer a range of data loggers from the most basic system with just a few channels, to expandable systems that measure hundreds of channels. Scan rates can be programmed from a few hours to 100,000 times per second, depending on the data logger model. Measurement types, processing algorithms, and recording intervals are also programmable.

Our systems have powerful on-board instruction sets simply choose sensor type, scan rate, measurement channel, etc. On-board mathematical and statistical processing allows data reduction in the field and allows measurements to be viewed in the desired units, whether that be microstrain, centimeters per second, revolutions per minute, meters, Amperes, or inches.

Our system's versatility extends to control as well—our systems can monitor and control external devices based on time or measured conditions allowing savings in time and equipment, and possibly preventing, or warning, of dangerous conditions. They are rugged enough to be in use in geotechnical studies and mines world wide.

Our systems are stand-alone. Once programmed and powered, no human or computer interaction is required, although data are typically downloaded to a PC for further analysis. A telecommunications or hardwire link allows data to be monitored and graphed in your office rather than in the field. Data from a number of stations and from a number of applications can be monitored from a single laptop or desktop computer.

The low power drain typically allows our data acquisition systems to be powered by solar panels and batteries. If 110/220 ac power, vehicle power, or external 12 Vdc batteries are available, you can use those as well. Non-volatile data storage and battery-backed clock ensure data capture and integrity.

Sensors

The versatility of our systems begins with sensor compatibility—they can measure virtually every commercially available sensor—allowing them to be used in a variety of ways for a variety of measurements. For example, the a CR10X can be used in slope stability, water quality, or equipment performance applications. Typical sensors that can be used include:

  • Carlson strain meters
  • Geokon vibrating wire strain gauges
  • Slope Indicator vibrating strip sensors
  • foil strain gauges (in quarter, half,or full bridge strain configurations) inclinometers
  • crack and joint sensors
  • tilt sensors
  • piezoresistive accelerometers
  • piezoelectric accelerometers
  • capacitive accelerometers
  • borehole accelerometers
  • servo force balance accelerometers

 

Because our data loggers have many channel types and programmable inputs, all of these sensor types can be measured by one data logger. Channel types include analog (single-ended and differential), pulse counters, switched excitation, continuous analog output, digital I/O, and anti-aliasing filter. Using switched or continuous excitation channels, our data loggers provide excitation for ratiometric bridge measurements.

 

Communications

The availability of multiple communications options for retrieving, storing, and displaying data also allows systems to be customised to meet exact needs. On-site communication options include direct connection to a PC or laptop, PC cards, storage modules, and data logger keyboard/display. Telecommunication options include short-haul, telephone (including voice-synthesized and cellular), radio frequency, multidrop, and satellite.