In order to improve the application of the damping force of isolation device for free-standing objects，a new damping mechanism is developed. Its structure and working mechanism are expounded，and its mechanical characteristic is deduced and verified. Combined with the target performance of an isolation device for cultural relics，the parameters of the damping mechanism are designed by numerical method，and contrasted with the shaking table test. The results indicate that the damping mechanism has a simple structure and stable performance. The isolation device optimized by damping parameters achieves the set isolation target under the premise of meeting the displacement limit. The test results are highly consistent with the numerical analysis results，which not only prove the correctness of the damping design，but also verifies the installation quality and operation effect of the isolation device. In addition，the coincidence degree between two results can provide a new method for design comparison and quality evaluation of the isolation device，especially the coincidence degree of relative displacement curves.

isolation device  /  damping mechanism  /  numerical analysis  /  shaking table test  /  lead screw  /  free-standing object