Data obtained from triaxial loading experiments conducted on thermally cracked Westerly granite which was initially dry and later saturated with water.

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 folder 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.

Mechanical and Ultrasonic data are provided for when the sample was dry. Only mechanical data are provided for saturated conditions.

Correlation coefficients and explained variances between the mid-spring Westerly Circulation Index (WCI) and influencing factors (1961-2022).

We investigate the microstructural controls of mixed mode dynamic fracture propagation in Westerly Granite and Berea Sandstone. Notched semi-circular bend samples of each rock type are loaded using a Split Hopkinson Pressure Bar apparatus and crack propagation across the sample is captured using an integrated Shimadzu Hypervision HPV-2 high-speed camera system. Using digital image correlation and a multivariable linear regression based in linear elastic fracture mechanics for near crack tip displacements, we make instantaneous measurements of the mode I (opening) and mode II (shear) components to the total stress intensity field during crack initiation and growth. Our results allow evaluation of fracture propagation in rocks with micromechanical models based on observations in engineered materials.

List of different indices in years when WC and WNPAC are both strong (weak) in spring.

We investigate the effect of rapid stress cycling on the dynamic compressive strength of Westerly Granite using a modified Split Hopkinson Pressure Bar approach. With this approach, generated load paths are composed of two distinct stress cycles separated a brief (hundreds of microseconds) dwell time. Under these loading conditions, the strength and critical strain rate thresholds required to pulverize samples can be reduced by a factor of two when compared with those required in traditional high strain rate tests with the Split Hopkinson Pressure Bar. These results suggest traditional experimental approaches may overestimate material strength when complex load paths are involved. […]

Correlation coefficients and explained variances between the mid-spring Rainfall Index (RI) and circulation indices (1961–2022).