We are highly skilled with the installation and use of the instruments listed below:
Vibrating Wire Piezometers
Extensometers are designed for the highly accurate measurement of strain and deflection. Extensometers measure strain, which is calculated as the change in length of a specimen divided by the original length (gauge length) of the specimen.
A Deep Benchmark consists of a pipe or rod, anchored at depth, surrounded by and disconnected from a sleeve pipe. The sleeve pipe protects the inner pipe or rod from drag caused by soil movement. The anchor is then grouted. The space between the rod and casing is filled with a bentonite slurry to minimize friction.
Benchmarks are typically regarded as stable points to provide references for elevations. In areas with expansive soils, special techniques are necessary to provide benchmarks that are free from ground movements. To prevent the movement of benchmarks due to heaving of expansive soils, benchmarks must be anchored below the depths where these movements originate.
Craig Test Boring Co., Inc. and Craig Geotechnical Drilling Co., Inc.
Mailing Address: PO Box 427, Mays Landing, NJ 08330
Craig Test Boring Co., Inc.
5230 Atlantic Avenue
Mays Landing, NJ 08330
Craig Geotechnical Drilling Co., Inc.
3143 Bordentown Rd, Bldg 4B
Parlin, NJ 08859