Recently,　MR　damper　has　become　an　important　smart　semi-active　control　device.　Firstly,　to　achieve　its　application　in　vibration　control　of　a　structural　building,　a　new　intelligent　control　strategy　ICA-LQG　combining　the　imperialist　competitive　algorithm　(ICA)　and　the　linear　quadratic　Gaussian　(LQG)　control　approach　was　proposed　to　calculate　ideal　controlling　forces.　To　overcome　difficulties　of　determining　weighted　matrixes　of　LQG　controller,　ICA　was　adopted　to　optimize　its　parameters　according　to　the　constraint　conditions　for　objectives　to　be　optimized　and　damping　force.　Secondly,　dynamic　characteristics　of　MR　damper　based　on　Bouc-Wen　model　were　obtained　with　tests.　Finally,　the　clipped-optimal　control　(COC)　was　used　to　convert　ideal　controlling　forces　calculated　with　ICA-LQG　into　the　control　current　of　MR　damper.　To　validate　the　effectiveness　of　the　proposed　semi-active　control　strategy　ICA-LQG-COC　integrating　ICA-LQG　and　COC,　a　3-story　frame　building　was　taken　as　an　example,　the　aseismic　results　obtained　with　uncontrolled,　two　passive　control,　traditional　LQG-COC　and　ICA-LQG-COC　approaches,　respectively　were　analyzed　contrastively.　The　numerical　results　obtained　under　three　seismic　excitations　demonstrated　that　in　all　control　methods　mentioned　above,　the　proposed　semi-active　control　strategy　ICA-LQG-COC　exhibits　the　most　excellent　comprehensive　control　performance　and　it　can　reduce　the　maximum　displacement　and　acceleration　responses　of　the　structural　building　to　the　utmost　extent.　©　2018,　Editorial　Office　of　Journal　of　Vibration　and　Shock.　All　right　reserved.