P. Skopek et Gp. Cyre, A RESISTANCE WIRE TRANSDUCER FOR CIRCUMFERENTIAL STRAIN-MEASUREMENT IN TRIAXIAL TESTS, ASTM geotechnical testing journal, 18(1), 1995, pp. 106-111
A resistance wire transducer was designed to measure circumferential d
eformation of a partially saturated triaxial specimen. It utilizes for
the measurement changing output voltage in a resistance wire transduc
er wound around the specimen as it bulges, i.e., increases in circumfe
rence. This circumferential change can be converted into lateral defor
mation. The proposed transducer is very small, so it is possible to mo
unt several of them along the height of a specimen and monitor accurat
ely its changing cross sections. The volume of the specimen at any rec
ording time can be calculated from the deformed cross section and axia
l deformation. The resistance wire transducer is a simple device whose
principle provides the potential for a broad spectrum of analogous ap
plications.