Data obtained from triaxial cyclic loading experiments conducted on dry Westerly granite at confining pressure ranging from 40 to 120 MPa. Text files (.txt) are raw, unprocessed time series of mechanical data including load, shortening and radial and axial strain gauge measurements. Except noted, units are in Volts. Strain gauge voltages can be converted into strain using gauge factor of 2.11 and amplification factor of 40. External shortening can be converted to sample shortening using a machine stiffness of 480 kN/mm. Raw ultrasonic data are combined in folders named BSF*. Data format is binary, and can be read using ASC ltd. software "Insite". Files "sensors.txt" contain ultrasonic sensor positions and time offset corrections.