Analog / Digital Direct and Residual Shear Testing Machine (Dead-Weight)

Analog / Digital Direct and Residual Shear Testing Machine (Dead-Weight) is with a rigid steel frame, backlash-free linear guides, a long stroke capacity, and simultaneous analog-digital measurement capability, it provides repeatable results under both peak and residual shear conditions. The dead-weight loading unit operates with a high-accuracy lever arm and calibrated weight set. The lever arm, positioned on a stable support, minimizes eccentricity and ensures the uniform transfer of normal force to the specimen.  The spherical seating on the loading head accommodates minor misalignments. Shear displacement is applied by a backlash-free screw-driven linear motion mechanism, providing smooth loading at a constant, controlled rate. A wide speed range allows appropriate selection of shear rate for dense, medium, and loose soils. The long-stroke design ensures continuous shearing into the residual range; end-position limit switches prevent mechanical overload and sensor damage. In the analog configuration, shear force is measured using a calibrated proving ring, while the horizontal shear displacement and the vertical settlement are read in real time using analog dial gauges. The shear box assembly supports various box sizes and is compatible with porous plates, high-permeability porous stones, and weight sets, enabling the testing of different soil types.