A Clamp-On Strain Transducer for Use on Geologic Materials

Abstract

The design, calibration and application o/ a clamp-on type strain transducer for the simultaneous monitoring of axial and transverse strain under both uniaxial and triaxial test conditions is described The transducer attaches directly to the test specimen and utilizes a number of linear variable differential transiormers to provide average strain data. Tests have been carried out on specimens of a number of metallic (steel, brass and aluminum) and geologic materials (granite, limestone and sandstone) at confining pressures oi up to 5,000 psi. No difficulties are contemplated in using the transducer at confining pressures of 10,000 psi and higher.