Abstract: An end-cap-to-piston coupling, with or without an integral load cell has been developed for triaxial test apparatus. One triaxial test apparatus shown has a housing, sample mounting apparatus in the housing, a load piston opening through the housing through which projects a load piston, and a load transfer coupling, with or without an integral load cell, interposed between the end cap and the load piston. In one aspect the coupling has a coupling body and a channel on one end into which the load piston is inserted to contact a shoulder of the coupling body. Another end of the coupling has a channel which receives a top end cap of a sample mounting arrangement. This channel may be sized and configured to receive a load transfer ball interposed between the coupling and the end cap or between the coupling and the piston. In one aspect a series of interchangeable top and bottom members are provided, each with a different diameter recess, to accommodate load pistons and sample end caps of different diameters.

Abstract: Load cell having a body with a ball recess therein and a ball removably disposed in the recess above a strain gauge means disposed in the body centrally below the ball recess, the load cell useful in measuring samples of geologic materials, e.g., core samples and for methods and apparatuses for measuring ultrasonic velocities in materials, particularly in the triaxial testing of low permeability rock samples.

Abstract: Methods and apparatuses for testing the effects of one or more fluids on geologic materials; in one aspect a method for quantitatively determining the hydration and swelling behavior of shale core samples in response to one or to different fluids circulated around a core sample confined under pressure in a test cell; apparatuses for circulating such fluids and for conducting such tests; and an adjustable LVDT holder.

Abstract: Methods and apparatuses for measuring ultrasonic velocities in materials are disclosed which, in one embodiment, include such methods and apparatuses for triaxial tests of low permeability rock samples, the apparatus including top and bottom end caps for mounting to a sample to be tested, each end cap having an ultrasonic transducer mounted therein for disposition in contact with the material to be tested for measuring the velocities of ultrasonic waves through the material. In another embodiment, at least one end cap having channels and a sensor for sensing changes in sample pore pressure is disclosed. In another aspect, a pressure generator or microaccumulator for changing the amount of a pore pressure fluid in the channels, thereby changing sample water content and making possible an efficient multistage test is disclosed. In another embodiment an end cap for such measurements is disclosed.