Terry U.S. Pat. No. 3,406,567 describes a portable shear test device that is used for testing bulk material, such as snow and soil. Iosipescu et al U.S. Pat. No. 3,566,681 is concerned with shear testing of rocks and other building materials.
Archer U.S. Pat. No. 4,409,841 is directed to a fatigue damage indicator having four holes in a test plate which provide four zones of crack initiation. Damm et al U.S. Pat. No. 2,812,658 sets out a method of fatigue testing hooks.
USPTO Backgrounds
USPTO Backgrounds