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The purpose of this investigation was to assess biofeedback (BF) and progressive muscle relaxation (PMR) and placebo-control training by means of a post-training transfer test. The subjects for the research were 30 women. Initial tests consisted of measuring the electromyographic response of the frontalis muscle of the forehead to stress. After the test procedures were completed, training sessions were conducted. BF subjects were instructed to use a feedback tone as a guide for relaxation. PMR subjects heard progressive relaxation instructions that were modified so that the majority of the training instructions were directed specifically to the frontalis muscle. The group of subjects receiving placebo training listened to a short, taped presentation on the benefits of relaxation after which they heard music that fluctuated in volume and tempo. Results showed that both BF and PMR training reduced resting electromyography significantly more than the placebo-control procedure. BF subjects had significantly greater reductions following training than either the PMR or control groups. (JD)

This research was undertaken to answer issues related to cavity expansion and in-situ testing using the pressuremeter. Emphasis of the research was placed upon validating the fundamental concepts underlying the cylindrical cavity expansion theory. Test were performed in a cuboidal shear device (CSD) at strain rates of 0.01%, 0.05%, 0.10%, 0.50%, 1.00% and 5.00% per minute on artificially sedimented specimens of kaolin clay and a kaolin-ground silica mixture with a plasticity index in the range similar to most clays. It was found from the experiments that the normalized shear strength (with respect to 0.01%/min) increases linearly with the logarithm of strain rate. The increase in undrained shear strength in the pressuremeter stress path is about 14.3% per log cycle for kaolin clay and 15-3% for the kaolin-silica mixture. The undrained shear strength in the conventional triaxial test was found to increase about 8 to 10% for a tenfold increase in strain rate. Therefore, it can be concluded that the undrained shear strength increases about 40-50% more in pressuremeter stress path tests than in the triaxial stress path tests. A new state variable, indicative of the fabric of clays is introduced. Based on these concepts and a general failure criterion, a simple model to predict failure parameters of anisotropic clays for many commonly encountered stress paths was developed. The model capability to interpret in situ strength measured under a given stress path and transfer it to another stress path was illustrated. Finally, the ability to obtain failure parameters for any stress path using data from a single CIUC test was demonstrated.