Most of the existing installation configurations for viscous dampers only consider the structural requirement, ignoring the functional requirement of the architecture. Therefore, an open-space viscous damper installation configuration is proposed and studied by some scholars. Based on the existing research findings, the working performance of the open-space installation configuration for viscous dampers (OSVDIC) in the actual structure remains to be studied. In order to investigate the working mechanism and damping effect of OSVDIC in the structure, the shaking table test is conducted on a three-story steel frame structure model with OSVDIC. Based on the conditions of the shaking table test, the finite-element model of a three-story steel frame structure model with the OSVDIC is established by SAP2000 for time-history analysis. The comparison shows that the numerical analysis results are in good agreement with the shaking table test results. The results of the shaking table test and numerical analysis show that, on the premise of reducing space occupation of the structure, adding the OSVDIC in the structure could significantly lower the seismic response. The effect of the parameters of the OSVDIC on the damping effect of the structure is analyzed by SAP2000. In summary, the structure with OSVDIC could meet the requirements of a certain level of damping effect, while also taking the needs of open space, wide vision, aesthetic appearance, and functional use into account.