Member B02 in the attached file is a rolled steel floorbeam (W21x182) which qualifies as a braced, compact section. It is non-composite (no concrete deck). LARS uses the elastic moment capacity (Fy)(Sx) = 50 ksi x 417 in3 / 12 = 1737.5 k-ft to compute LRFR Strength I rating. However, based on AASHTO specifications and a comparison run using alternate LRFD software (PennDOT STLRFD), we think the Strength I rating should be based on the plastic moment capacity, (Fy)(Zx) = 50 ksi x 476 in3 /12 = 1983 k-ft.
Note that the service moment stress (Strength II) computed by both LARS and STLRFD agree (40 ksi).
A review of our customization settings shows nothing that would explain this, and the "always non-compact" code option is unchecked. Please confirm what LARS is doing, and if it is in accordance with AASHTO LRFR/LRFD specifications.
Note that the file suffix has been renamed from BMD to TXT to allow upload.
[BridgeModel 1] [File Format (C) Copyright 1997-2010 Bentley Systems Inc.] [ConnectProjectID] {00000000-0000-0000-0000-000000000000} [ConnectProjName] [BridgeID] 1000011_20170112CY01_FLOORBEAM_COMPARISON [DataSource] BridgeModeler [FileName] [StateBridgeID] 1000011 [AnalystName] MAF [MasterUnits] (ft.) [SubUnits] (in.) [VAnalystName] MAF [Date] 01/23/17 [Inventory] 1 [InvVName] HL93 [Operating] 1 [OpVName] HL93 [OpASR] [Posting] 1 [PstVName1] 3 [PstVName2] 3S2 [PstVName3] 3-3 [PstASR] [Special] 0 [SpcVName] [SpcASR] [BatchControl] *LR* [StructureType] Truss [YearConst] 2016 [StructureLength] 60.5 [BNumSpans] 1 [StructureXSec] 1017 [RoadWidth] 32 [CurbDistA] 36 [MarkedRoute] [KeyRoute] [County] Hunterdon [DistrictNumber] [Route] [Section] [Location] [LocationType] [NbiID] 1000011 [FacilityCarried] Kingwood Road (CR 519) [FeatureIntersected] Lockatong Creek [StructureStatus] [StructureFlag] [FullSectionEffectiveStiffForEntireBeam] 0 [Comments] Per MBE; analyis based on 2 - 12' lanes. Edge distance set to 36" to restrict loading on floorbeams to 2 lanes. [InvRateExe] A [OprRatExe] A [PostRatExe] A [PhiS] 1.00 [ADTT] 30 [PermitType] None [SPermitType] [CrossSection] { [Symmetrical] N } [MemberID] B01 / [ConstMaterial] SS [ShearRating] [MatStrength1] 50000 [MatStrength2] [MatStrength3] [MatStrength4] [MatStrength5] [MatStrength6] [MatStrength7] [MatStrength8] [MatStrength9] [MatStrength10] [MatStrength11] [MatStrength12] [MatStrengthV] [LiveLoadFact] 12.1 [LiveLoadFact2] [TrussLLDFForLRFD] [CLRoadwayToCLFloorbeam] 0.0 [MemberType] Flexural [MemberFunction] Floor Beam-Interior [MemberDescription] 01-IB001 [GirderType] [FasciaEdgeDist] 0.0 [InvIFMax] 30 [InvIFMin] 10 [OpIFMax] 30 [OpIFMin] 10 [PstIFMax] 30 [PstIFMin] 10 [SpcIFMax] 30 [SpcIFMin] 10 [IFAASHTOMultiplier] 1 [IFOvr_LRFR] 33 [IFFatigue_LRFR] 15 [SectionChangeGenerateCheckPoints] 0 [PhiC_Mem] 1.0 [PhiS_Mem] 0.85 [MNumSpans] 1 [Fixity] Both [LeftOverhang] [RightOverhang] [ShearAnalysis] Yes [StiffnerCode] Not [MomentRedist] No [NeverCompact] No [RatngMeth_Mem] [LLDFType] [GridThk] [BeamType] [DeckType] [DesignLanes] [BeamSpacing] [NoBeams] [OutToOutWidth] [GeneralSlabThickness] [Travelway] [LLDFXSecSkewAngle] [Spans] { [SpanLength] 43.5000 } [DLElems] { < [ElementType] Concentrated [ElementID] 1 [Symmetry] [Span] [Wl] 0.7 [Wr] 0.7 [LocationType] 8 [Length] 0 [LeftRefElem] R1 [LeftRefPoint] Left [LeftRefOffset] 0 > < [ElementType] Concentrated [ElementID] 2 [Symmetry] [Span] [Wl] 0.7 [Wr] 0.7 [LocationType] 8 [Length] 0 [LeftRefElem] R2 [LeftRefPoint] Left [LeftRefOffset] 0 > < [ElementType] Concentrated [ElementID] 3 [Symmetry] [Span] [Wl] 3 [Wr] 3 [LocationType] 8 [Length] 0 [LeftRefElem] R1 [LeftRefPoint] Left [LeftRefOffset] 21.75 > < [ElementType] Concentrated [ElementID] 4 [Symmetry] [Span] [Wl] 3 [Wr] 3 [LocationType] 8 [Length] 0 [LeftRefElem] P003 [LeftRefPoint] Left [LeftRefOffset] 3 [Symmetrical] 1 [SymmetricalID] 5 > < [ElementType] Concentrated [ElementID] 5 [Symmetry] [Span] [Wl] 3 [Wr] 3 [LocationType] 8 [Length] 0 [LeftRefElem] R1 [LeftRefPoint] Center [LeftRefOffset] 18.75 [SymmetricalParentID] 4 > < [ElementType] Concentrated [ElementID] 6 [Symmetry] [Span] [Wl] 3 [Wr] 3 [LocationType] 8 [Length] 0 [LeftRefElem] P004 [LeftRefPoint] Left [LeftRefOffset] 3 [Symmetrical] 1 [SymmetricalID] 7 > < [ElementType] Concentrated [ElementID] 7 [Symmetry] [Span] [Wl] 3 [Wr] 3 [LocationType] 8 [Length] 0 [LeftRefElem] R1 [LeftRefPoint] Center [LeftRefOffset] 15.75 [SymmetricalParentID] 6 > < [ElementType] Concentrated [ElementID] 8 [Symmetry] [Span] [Wl] 3 [Wr] 3 [LocationType] 8 [Length] 0 [LeftRefElem] P006 [LeftRefPoint] Left [LeftRefOffset] 3 [Symmetrical] 1 [SymmetricalID] 9 > < [ElementType] Concentrated [ElementID] 9 [Symmetry] [Span] [Wl] 3 [Wr] 3 [LocationType] 8 [Length] 0 [LeftRefElem] R1 [LeftRefPoint] Center [LeftRefOffset] 12.75 [SymmetricalParentID] 8 > < [ElementType] Concentrated [ElementID] 10 [Symmetry] [Span] [Wl] 3 [Wr] 3 [LocationType] 8 [Length] 0 [LeftRefElem] P008 [LeftRefPoint] Left [LeftRefOffset] 3 [Symmetrical] 1 [SymmetricalID] 11 > < [ElementType] Concentrated [ElementID] 11 [Symmetry] [Span] [Wl] 3 [Wr] 3 [LocationType] 8 [Length] 0 [LeftRefElem] R1 [LeftRefPoint] Center [LeftRefOffset] 9.75 [SymmetricalParentID] 10 > < [ElementType] Concentrated [ElementID] 12 [Symmetry] [Span] [Wl] 3 [Wr] 3 [LocationType] 8 [Length] 0 [LeftRefElem] P010 [LeftRefPoint] Left [LeftRefOffset] 3 [Symmetrical] 1 [SymmetricalID] 13 > < [ElementType] Concentrated [ElementID] 13 [Symmetry] [Span] [Wl] 3 [Wr] 3 [LocationType] 8 [Length] 0 [LeftRefElem] R1 [LeftRefPoint] Center [LeftRefOffset] 6.75 [SymmetricalParentID] 12 > < [ElementType] Concentrated [ElementID] 14 [Symmetry] [Span] [Wl] 3 [Wr] 3 [LocationType] 8 [Length] 0 [LeftRefElem] P010 [LeftRefPoint] Left [LeftRefOffset] 3 [Symmetrical] 1 [SymmetricalID] 15 > < [ElementType] Concentrated [ElementID] 15 [Symmetry] [Span] [Wl] 3 [Wr] 3 [LocationType] 8 [Length] 0 [LeftRefElem] R1 [LeftRefPoint] Center [LeftRefOffset] 6.75 [SymmetricalParentID] 14 > < [ElementType] Concentrated [ElementID] 16 [Symmetry] [Span] [Wl] 1.8 [Wr] 1.8 [LocationType] 8 [Length] 0 [LeftRefElem] P014 [LeftRefPoint] Left [LeftRefOffset] 3 [Symmetrical] 1 [SymmetricalID] 17 > < [ElementType] Concentrated [ElementID] 17 [Symmetry] [Span] [Wl] 1.8 [Wr] 1.8 [LocationType] 8 [Length] 0 [LeftRefElem] R1 [LeftRefPoint] Center [LeftRefOffset] 3.75 [SymmetricalParentID] 16 > } [SSElems] { < [ElementType] Std Section [ElementID] 1 [Designation] W21X166 [LocationType] 7 [LeftRefElem] R1 [LeftRefPoint] Center [LeftRefOffset] 0 [RightRefElem] R2 [RightRefPoint] Center [RightRefOffset] 0 > } [LBElems] { < [ElementType] Not Supported [ElementID] 1 [Span] [Range] [NumSpaces] [SpacingLength] [MaxStiffSpace] 43.5 [MinStiffSpace] 43.5 [Position] Bottom [LocationType] 7 [LeftRefElem] R1 [LeftRefPoint] Center [LeftRefOffset] 0 [RightRefElem] R2 [RightRefPoint] Center [RightRefOffset] 0 > < [ElementType] Supported [ElementID] 1 [Span] [Range] [NumSpaces] 12 [SpacingLength] 3 [MaxStiffSpace] [MinStiffSpace] [Position] Top [LocationType] 7 [LeftRefElem] R1 [LeftRefPoint] Center [LeftRefOffset] 3.75 [RightRefElem] R2 [RightRefPoint] Center [RightRefOffset] -3.75 > < [ElementType] Supported [ElementID] 2 [Span] [Range] [NumSpaces] 1 [SpacingLength] 3.75 [MaxStiffSpace] [MinStiffSpace] [Position] Top [LocationType] 7 [LeftRefElem] R1 [LeftRefPoint] Center [LeftRefOffset] 0 [RightRefElem] SP001 [RightRefPoint] Left [RightRefOffset] 0 > < [ElementType] Supported [ElementID] 3 [Span] [Range] [NumSpaces] 1 [SpacingLength] 3.75 [MaxStiffSpace] [MinStiffSpace] [Position] Top [LocationType] 7 [LeftRefElem] SP001 [LeftRefPoint] Right [LeftRefOffset] 0 [RightRefElem] R2 [RightRefPoint] Center [RightRefOffset] 0 > } \ [MemberID] B02 / [ConstMaterial] SS [ShearRating] [MatStrength1] 50000 [MatStrength2] [MatStrength3] [MatStrength4] [MatStrength5] [MatStrength6] [MatStrength7] [MatStrength8] [MatStrength9] [MatStrength10] [MatStrength11] [MatStrength12] [MatStrengthV] [LiveLoadFact] 12.1 [LiveLoadFact2] [TrussLLDFForLRFD] [CLRoadwayToCLFloorbeam] 0.0 [MemberType] Flexural [MemberFunction] Floor Beam-Interior [MemberDescription] 01-IB002 [GirderType] [FasciaEdgeDist] 0.0 [InvIFMax] 30 [InvIFMin] 10 [OpIFMax] 30 [OpIFMin] 10 [PstIFMax] 30 [PstIFMin] 10 [SpcIFMax] 30 [SpcIFMin] 10 [IFAASHTOMultiplier] 1 [IFOvr_LRFR] 33 [IFFatigue_LRFR] 15 [SectionChangeGenerateCheckPoints] 0 [PhiC_Mem] 1.0 [PhiS_Mem] 1.0 [MNumSpans] 1 [Fixity] None [LeftOverhang] [RightOverhang] [ShearAnalysis] Yes [StiffnerCode] Not [MomentRedist] No [NeverCompact] No [RatngMeth_Mem] [LLDFType] [GridThk] [BeamType] [DeckType] [DesignLanes] [BeamSpacing] [NoBeams] [OutToOutWidth] [GeneralSlabThickness] [Travelway] [LLDFXSecSkewAngle] [Spans] { [SpanLength] 43.5000 } [DLElems] { < [ElementType] Concentrated [ElementID] 1 [Symmetry] [Span] [Wl] 0.7 [Wr] 0.7 [LocationType] 8 [Length] 0 [LeftRefElem] R1 [LeftRefPoint] Left [LeftRefOffset] 0 > < [ElementType] Concentrated [ElementID] 2 [Symmetry] [Span] [Wl] 0.7 [Wr] 0.7 [LocationType] 8 [Length] 0 [LeftRefElem] R2 [LeftRefPoint] Left [LeftRefOffset] 0 > < [ElementType] Concentrated [ElementID] 3 [Symmetry] [Span] [Wl] 3 [Wr] 3 [LocationType] 8 [Length] 0 [LeftRefElem] R1 [LeftRefPoint] Left [LeftRefOffset] 21.75 > < [ElementType] Concentrated [ElementID] 4 [Symmetry] [Span] [Wl] 3 [Wr] 3 [LocationType] 8 [Length] 0 [LeftRefElem] P003 [LeftRefPoint] Left [LeftRefOffset] 3 [Symmetrical] 1 [SymmetricalID] 5 > < [ElementType] Concentrated [ElementID] 5 [Symmetry] [Span] [Wl] 3 [Wr] 3 [LocationType] 8 [Length] 0 [LeftRefElem] R1 [LeftRefPoint] Center [LeftRefOffset] 18.75 [SymmetricalParentID] 4 > < [ElementType] Concentrated [ElementID] 6 [Symmetry] [Span] [Wl] 3 [Wr] 3 [LocationType] 8 [Length] 0 [LeftRefElem] P004 [LeftRefPoint] Left [LeftRefOffset] 3 [Symmetrical] 1 [SymmetricalID] 7 > < [ElementType] Concentrated [ElementID] 7 [Symmetry] [Span] [Wl] 3 [Wr] 3 [LocationType] 8 [Length] 0 [LeftRefElem] R1 [LeftRefPoint] Center [LeftRefOffset] 15.75 [SymmetricalParentID] 6 > < [ElementType] Concentrated [ElementID] 8 [Symmetry] [Span] [Wl] 3 [Wr] 3 [LocationType] 8 [Length] 0 [LeftRefElem] P006 [LeftRefPoint] Left [LeftRefOffset] 3 [Symmetrical] 1 [SymmetricalID] 9 > < [ElementType] Concentrated [ElementID] 9 [Symmetry] [Span] [Wl] 3 [Wr] 3 [LocationType] 8 [Length] 0 [LeftRefElem] R1 [LeftRefPoint] Center [LeftRefOffset] 12.75 [SymmetricalParentID] 8 > < [ElementType] Concentrated [ElementID] 10 [Symmetry] [Span] [Wl] 3 [Wr] 3 [LocationType] 8 [Length] 0 [LeftRefElem] P008 [LeftRefPoint] Left [LeftRefOffset] 3 [Symmetrical] 1 [SymmetricalID] 11 > < [ElementType] Concentrated [ElementID] 11 [Symmetry] [Span] [Wl] 3 [Wr] 3 [LocationType] 8 [Length] 0 [LeftRefElem] R1 [LeftRefPoint] Center [LeftRefOffset] 9.75 [SymmetricalParentID] 10 > < [ElementType] Concentrated [ElementID] 12 [Symmetry] [Span] [Wl] 3 [Wr] 3 [LocationType] 8 [Length] 0 [LeftRefElem] P010 [LeftRefPoint] Left [LeftRefOffset] 3 [Symmetrical] 1 [SymmetricalID] 13 > < [ElementType] Concentrated [ElementID] 13 [Symmetry] [Span] [Wl] 3 [Wr] 3 [LocationType] 8 [Length] 0 [LeftRefElem] R1 [LeftRefPoint] Center [LeftRefOffset] 6.75 [SymmetricalParentID] 12 > < [ElementType] Concentrated [ElementID] 14 [Symmetry] [Span] [Wl] 3 [Wr] 3 [LocationType] 8 [Length] 0 [LeftRefElem] P010 [LeftRefPoint] Left [LeftRefOffset] 3 [Symmetrical] 1 [SymmetricalID] 15 > < [ElementType] Concentrated [ElementID] 15 [Symmetry] [Span] [Wl] 3 [Wr] 3 [LocationType] 8 [Length] 0 [LeftRefElem] R1 [LeftRefPoint] Center [LeftRefOffset] 6.75 [SymmetricalParentID] 14 > < [ElementType] Concentrated [ElementID] 16 [Symmetry] [Span] [Wl] 1.8 [Wr] 1.8 [LocationType] 8 [Length] 0 [LeftRefElem] P014 [LeftRefPoint] Left [LeftRefOffset] 3 [Symmetrical] 1 [SymmetricalID] 17 > < [ElementType] Concentrated [ElementID] 17 [Symmetry] [Span] [Wl] 1.8 [Wr] 1.8 [LocationType] 8 [Length] 0 [LeftRefElem] R1 [LeftRefPoint] Center [LeftRefOffset] 3.75 [SymmetricalParentID] 16 > } [SSElems] { < [ElementType] Std Section [ElementID] 1 [Designation] W21X182 [LocationType] 7 [LeftRefElem] R1 [LeftRefPoint] Center [LeftRefOffset] 0 [RightRefElem] R2 [RightRefPoint] Center [RightRefOffset] 0 > } [LBElems] { < [ElementType] Not Supported [ElementID] 1 [Span] [Range] [NumSpaces] [SpacingLength] [MaxStiffSpace] 43.5 [MinStiffSpace] 43.5 [Position] Bottom [LocationType] 7 [LeftRefElem] R1 [LeftRefPoint] Center [LeftRefOffset] 0 [RightRefElem] R2 [RightRefPoint] Center [RightRefOffset] 0 > < [ElementType] Continuous [ElementID] 1 [Span] [Range] [NumSpaces] [SpacingLength] [MaxStiffSpace] [MinStiffSpace] [Position] Top [LocationType] 7 [LeftRefElem] R1 [LeftRefPoint] Center [LeftRefOffset] 0 [RightRefElem] R2 [RightRefPoint] Center [RightRefOffset] 0 > } \
Thank you!