Axial Deformation Measurement in Repeated Load Triaxial Testing

This paper describes a method of axial deformation measurement for use in repeated load triaxial testing of pavement materials. An internal deformation measurement system is necessary because of the low strain regime involved, but normal transducers can only be used in an inert cell fluid. As this is both expensive and messy, the use of sealed transducers in water is preferable, but the cost of such units induces the use of a system based on a single transducer. Therefore, aluminium rings are used in an arrangement that allows the mean axial deformation over the central portion of the specimen to be determined by the use of a single hermetically sealed displacement transducer.