A large testing facility is being completed at the University of Houston to test full-sized reinforced concrete panels under in-plane loadings. It consists of thirty-seven 100-ton hydraulic jacks embedded in a large steel reaction frame. The jacks are controlled by a sophisticated hydraulic system to produce in-plane normal and shear stresses in a panel. Extensive tests of reinforced concrete panels will be conducted to generate material laws which are required in the development of the softened truss model theory. The equipment will upgrade the facility to have the capability to apply out-of-plane loadings, including bending moments, torsional moments and out-of-plane shear stresses. These out-of-plane loadings will be supplied by seventeen additional 60-ton jacks. Since both in-plane and out-of-plane stresses occur in an element of a shell structure, the upgraded facility is known as a shell element tester.