Rock-mass experiments on jointed welded tuff

Field tests emphasizing development and demonstration of equipment and instruments are part of Sandia National Laboratories` rock mechanics program. The successful conduct of demonstration tests has allowed assessment of test techniques and an evaluation of the mechanical behavior of jointed welded tuff. The most recent endeavor consisted of high-pressure flatjack test yielding load and deformation histories sufficient to evaluate rock-mass modulus and to provide in situ results against which analytical models can be compared. Test results were used to calculate rock-mass moduli which compare favorably with previous estimates for jointed welded tuff. 6 refs., 7 figs., 1 tab.