Experimental and numerical studies of a novel three-dimensional isolation device incorporating disc springs with U-shaped dampers

To improve the asymmetric hysteretic capacity, enhance the insufficient energy consumption capacity, and release the horizontal constraint of disc springs, this study proposes a novel three-dimensional isolation device, which is mainly composed of disc springs, U-shaped dampers, and a sliding layer. The novel device is to bear the dead weight of superstructures by the disc springs and dissipate the major seismic energy by the U-shaped dampers. A quasi-static test is conducted to verify the proposed working mechanism. Furthermore, the finite element model of the novel device built by Abaqus software is validated based on the test results. Parameter analysis indicates that the length of straight parts and the thickness of U-shaped dampers significantly affect the horizontal mechanical behavior of the novel device. Moreover, the outer diameter of disc springs, and the length of straight parts, and the thickness of U-shaped dampers play essential roles to enhance the vertical mechanical behavior of the novel device. Detailed design processes of the novel device are conducted based on the numerical results.