Based　on　quasi-static　test　results,　fiber　element　models　using　OpenSees　software　were　established　to　investigate　the　effects　of　major　factors　on　the　horizontal　load-displacement　skeleton　curve　of　a　uniform　sectional　CFST　lattice　column　with　flat　laced　tubes.　Then　a　tri-linear　model　was　proposed　to　simulate　the　load-displacement　skeleton　curve,　and　the　simplified　calculation　methods　of　related　control　parameters　of　the　model　were　also　put　forward　through　theoretical　derivation　and　statistics　analysis,　including　the　elastic　stiffness　calculation　formula　considering　the　shear　deformation　of　CFST　limbs　and　lacing　tubes;　the　horizontal　peak　load　calculation　formula　based　on　a　virtual　work　principle　and　the　correlation　curves　between　axial　force　and　bending　moment;　the　simplified　calculation　method　of　the　peak　displacement　and　ultimate　displacement　for　which　the　displacement　ductility　factors　obtained　by　statistical　data　can　be　selected　flexibly　according　to　the　actual　requirements.　Compared　with　the　results　of　quasi-static　tests,　FEM　parameter　analysis,　and　extended　parameter　analysis　for　actual　structural　size,　the　tri-linear　model　can　effectively　simulate　the　skeleton　curve　of　such　structures,　and　the　simplified　calculation　formulas　for　related　control　parameters　of　a　skeleton　curve　have　high　accuracy.　©　2016,　Engineering　Mechanics　Press.　All　right　reserved.