A full-scale system for testing roof bolts has been furnished to the Bureau of Mines. The system uses a full-size model of a mine entry made from sand and portland cement concrete. A servosystem with hydraulic actuators and load pads provide lateral, vertical, and shear loads to simulate premining and postmining conditions. Instruments embedded in the model determine strains as affected by the installed roof bolts. To insure stability, pressure limit detectors make certain that vertical loads are at a safe level before horizontal loads are applied. Set points provide for interlocks and safety shutdown in the event of pressure or error signal in excess of preset limits. There is a data acquisition system and computer for control and compilation of data. Peripherals include a crt console, a hard copy unit, and a magnetic tape unit. The control and data system can operate with input determined by the computer, or by manual or auxiliary means.