Ground　motion　involves　significant　nonstationary　in　time　domain　and　frequency　domain.　The　traditional　uniform　modulation　model　cannot　fully　characterize　the　nonstationary　in　both　time　domain　and　frequency　domain,　which　debases　the　accuracy　and　precision　of　structural　random　vibration　analysis.　In　order　to　overcome　the　above　defects,　a　nonuniform　modulated　ground　motion　model　is　established,　which　is　generated　by　the　dot　product　of　the　multi-peak　smooth　intensity　envelope　and　the　nonstationary　noise　signal.　The　new　model　can　fully　represent　the　oscillation　and　attenuation　characteristics　of　earthquake　wave　in　time　domain,　at　the　same　time,　its　spectral　characteristics　are　close　to　the　real　values.　Based　on　this　study,　the　nonstationary　evolution　spectrum　model　is　established,　which　simultaneously　sets　the　time　and　frequency　as　variables.　The　analysis　results　show　that　these　two　models　are　superior　to　the　uniform　modulation　model　in　both　time　domain　and　frequency　domain.　In　view　of　the　form　and　characteristics　of　the　above　seismic　stochastic　process　model,　the　analytic　method　for　solving　the　traditional　structural　vibration　response　is　improved.　Through　a　large　number　of　examples,　it　is　proved　that　the　nonstationary　characteristics　in　both　time　and　frequency　domains　cannot　be　fully　obtained　when　the　structural　random　response　is　calculated　according　to　the　uniform　modulation　model,　and　the　unsafe　results　are　usually　obtained.　On　the　contrary,　more　accurate　structural　response　characteristics　and　more　detailed　evolution　process　can　be　obtained　when　the　two　new　improved　models　are　used.　©　2019,　Editorial　Department　of　JVMD.　All　right　reserved.