Ground　subsidence　induced　by　collapse　leads　to　suspension　or　subsidence　of　pipes.　It　can　cause　stress　concentration,　which　is　a　significant　factor　being　a　threat　to　safe　operation　of　pipelines.　Then　the　pipes　can　be　divided　into　suspended　segment　and　buried　segment.　Based　on　the　theories　of　the　Vlasov　Elastic　Foundation　Beam　and　simply-supported　beams,　a　mechanical　model　of　interaction　between　the　pipelines　and　the　soils　was　built　up.　According　to　the　compatibility　conditions　of　the　hanging　and　non-hanging　parts,　this　paper　solved　differential　equations　describing　the　deflection　of　pipeline　and　derived　the　formulas　of　deflections　and　internal　forces.　Connecting　with　pipeline　operation　status,　the　formulas　of　piping　stresses　were　deduced　by　piping　stress　analysis.　Meanwhile　piping　stress　analysis　can　define　the　scope　of　application　of　the　model.　The　calculated　results　were　compared　to　the　measured　values　and　results　by　the　Winkler　model.　It　is　shown　that　the　calculated　results　of　the　Vlasov　model　are　more　suitable　than　the　Winkler　model　in　analyzing　stresses　and　deformation　of　pipelines.　According　to　the　normalized　analysis　of　main　affecting　factors　including　pipe　material,　pipe　dimension,　pipe　depth　and　length　of　collapse,　the　length　of　collapse　is　the　most　important　factor　for　the　safe　operation　of　pipelines.　©　2018,　Engineering　Mechanics　Press.　All　right　reserved.