Geokon Inc products

The Model 3900 Embedment Strain Gage is designed for the measurement of dynamic strains in concrete structures, earth fills and soils. It comprises a full bridge strain gaged proving ring coupled, between two flanges, with a spring and shaft. When the flanges move relative to one another, the tension in the spring changes and hence the strain in the proving ring. A PVC tube serves as a protective housing and holds the gage at the desired initial tension.

The Model 4000 Strain Gage is designed primarily for arc welding to steel structures such as tunnel linings, excavation bracing, piles and bridges. The gage has a 150 mm gage length (longer or shorter versions are also available), a 3000 µε range and a 1 µε sensitivity. The gage can be adapted for bonding to concrete or for bolting to steel surfaces by modification of the end blocks.

The Model 4400 Embedment Jointmeter is designed for use across construction joints, such as those between adjacent blocks in a concrete dam. It is normally embedded across the joint to monitor the expansion or contraction of the joint. The use of internal universal joints allows for a degree of shearing motion.

The Model 4410 Strandmeter is designed to measure strains in tendons and steel cables. Two clamps at each end of the strandmeter hold it firmly onto the cable. Various size clamps are available.

The Model A-1 Single Position Rod Extensometer is a very simple, rugged and reliable instrument, easily installed and completely recessed within the borehole for optimum protection. The Model A-1 is a natural first choice for monitoring the safety in and around tunnels and mine openings. Options are also available with electrical transducers for remote readout and/or continuous monitoring

The Model 3400 Semiconductor Piezometers and Pressure Transducers are intended for dynamic measurements of fluid and/or pore water pressures in standpipes, boreholes, embankments, pipelines, pressure vessels, reservoirs, etc. They are also used for static pressure movement where the readout system is incompatible with vibrating wire type transducers. Three transducer output options are available.

The Model 4600 Settlement System is designed for the remote measurement of surface or subsurface settlement in fills, surcharges, dams, embankments, etc. A borehole is drilled which allows a pressure transducer to be anchored to solid ground below the area of settlement. A fluid filled tube extends upward connecting the transducer to a reservoir which is located in the moving strata or fill. The measurement of fluid pressure indicates the elevation difference between the sensor and the reservoir. This design eliminates the need for long liquid filled tubes. Systems capable of measuring at multiple levels are also available.

The Model 4800 Earth Pressure Cells are designed to measure total pressure in earth fills and embankments. All cells consist of two circular stainless steel plates welded together around their periphery and spaced apart by a narrow cavity filled with de-aired oil. Changing earth pressure squeezes the two plates together causing a corresponding increase of fluid pressure inside the cell. A vibrating wire pressure transducer converts this pressure into an electrical signal which is transmitted to the readout location.

The Model 4900 Vibrating Wire Load Cell consists of a cylinder of high-strength steel with 3, 4 or 6 vibrating wire strain gages located around the circumference of the cell. Loads applied to the cell are measured by the vibrating wire strain gages. The effects of uneven and eccentric loading are minimized by averaging the output of all 3, 4 or 6 individual readings.

The Model GK-604D Digital Inclinometer System is delivered in its entirety and includes a Model 6100D Digital Inclinometer Probe, a reel-mounted cable and a Field PC. The Model 6100D contains electronics to convert the analog voltage into a digital signal, which is transmitted by the control cable to the cable reel containing the Interface, which communicates via Bluetooth® to the Model FPC-1 Field PC. A Digital Compass is built into the Inclinometer Probe to correct the inclinometer data sets for any twist (or spiraling) in the inclinometer casings. The spiral survey data is presented on (and stored in) the same FPC-1 Field PC used for taking inclinometer readings.