navigating aisc 36016 - hss connection design: limit …...design codes, specifications and...
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NAVIGATING AISC 360-16 HSS CONNECTION
DESIGN: LIMIT STATE TABLES
PRESENTED BY CATHLEEN JACINTO, SE, PEFORSE CONSULTING, LLC
HSS HOLLOW STRUCTURAL SECTIONS
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WELCOME
HSS HOLLOW STRUCTURAL SECTIONS
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WELCOME
HSS HOLLOW STRUCTURAL SECTIONS
q History lessonq Change – the only thing in life that is certain.q Limits of Applicabilityq STI Resource: Limit State Tablesq Limit states in Chapter Jq Additional Resources
AGENDA
HSS HOLLOW STRUCTURAL SECTIONS
HOW WE GOT HERE
HSS HOLLOW STRUCTURAL SECTIONS
HOW WE GOT HERE
HSS HOLLOW STRUCTURAL SECTIONS
HOW WE GOT HERE
HSS HOLLOW STRUCTURAL SECTIONS
HOW WE GOT HERE
HSS HOLLOW STRUCTURAL SECTIONS
q The problem with 360-10, Chapter K is…q Tablesq Prescriptiveq Unique to the Spec
q Content is repetitiveq Limits of Applicability
AISC 360-10, CH K
HSS HOLLOW STRUCTURAL SECTIONS
q “Additional Requirements for HSS and Box-Section Connections”
q Introduction clearly states the requirements of Chapter J also apply
AISC 360-16,CH K
HSS HOLLOW STRUCTURAL SECTIONS
q If met, connections only need to be designed for the provided limit states
q If not met, not prohibited, but must be designed by rational analysis
q Angle (q) – previously was limited to 30° (min) - now user note explains that if < 30°, weld is difficult (still not recommended)
q New limit pertaining to the end of memberq 𝑙"#$ ≥ 𝐷 1.25 − ,-//
0
AISC 360-16,LIMITS OF APPLICABILITY
HSS HOLLOW STRUCTURAL SECTIONS
q Largely unchanged
q New Limit of Applicabilityq Shear tab not mentionedq Cap plate not mentioned
Packer, 2015
ROUND SECTIONS
1
THROUGH PLATE-TO-ROUND HSS CONNECTIONS by Jeffrey A. Packer1
1Bahen/Tanenbaum Professor of Civil Engineering, University of Toronto, Ontario, Canada _____________________________________________________________________________________ Designrecommendationsforlongitudinalandtransversebranch(orgusset)plateT-connections,withtheplatesubjectedtoaquasi-staticloadaxialtotheplate,arenowwell-establishedinmodernsteeldesign codes, specifications and international guides, including AISC 360 Chapter K (AISC, 2010). Animportant feature of all these recommendations, however, is that the connection design capacity isindependentofthesenseofthebranchplateload;i.e.,thesameconnectionstrengthisassumedforbothbranchtensionandcompressionloadingcases,withalowerboundbeingtakentoaccommodatebothloadcases. A widely used stiffening and strengtheningmethod is a plate-to-tube connection where thebranchplate isslottedthroughtheHSSandweldedtotwoopposingfaces(seeFigure1).Thishastheadvantageofengagingmuchmoreofthecrosssectioninloadresistance,andhencehasahighercapacitythantheequivalentbranchplateconnection,but the throughplateconnection isamoredifficultandmoreexpensivefabricationprocedure.Also,apartofthethroughplateprotrudesbeyondthefarsideoftheHSS(Figure1),whichmayaffectconnectionstothatsideoftheHSS.
Figure1:ExampleofathroughplateconnectiontoaroundHSS Researchonlongitudinalthroughplateconnectionstorectangular/squareHSSmembers(KosteskiandPacker,2003)showedthattheconnectionstrengthwasdoublethatoftheequivalentbranchplate
HSS HOLLOW STRUCTURAL SECTIONS
AXIALLY LOADED CONNECTION
MOMENT CONNECTION
HSS 8x8x12 COLUMN
A500CFy = 50 ksiFu = 62 ksi W18x35 BEAM
A992, Fy=50 ksi, Fu=65 ksi,
Pu=60k
AISC 360-10
HSS HOLLOW STRUCTURAL SECTIONS
q AISC 360-16q Per K2.3 – The available strength of connections
to rectangular HSS with concentrated loads shall be determined based on the applicable limit states from Chapter J.
RECTANGULAR SECTIONS
HSS HOLLOW STRUCTURAL SECTIONS
q References Chapter Jq Fundamentally
RECTANGULAR SECTIONS
HSS HOLLOW STRUCTURAL SECTIONS
LIMIT STATE TABLES
STI Resource: Limit State Tablesq How will Tables help?
q Serves as a transition key from AISC 360-10 to AISC 360-16
q Guidance in applying AISC 360-16 Spec Chapter J to HSS Connections
q Provides connection available strength for each HSS limit state
q Clarifies limits of applicability, if anyq Clarifies end distance requirements for each limit
state
HSS HOLLOW STRUCTURAL SECTIONS
LIMIT STATE TABLES
For each limit state:
q AISC 360-10 and 14th Ed. Manual in left column
q AISC 360-16 and 15th Ed. Manual in right column
HSS HOLLOW STRUCTURAL SECTIONS
LIMIT STATE TABLES
For each limit state:q Connection
capacity equation references
q Variable substitutions specific to HSS
q Limits of applicability in AISC 360-16 only where specifically noted
HSS HOLLOW STRUCTURAL SECTIONS
LIMIT STATE TABLES
SHEARAXIAL
TRUSSMOMENT
HSS HOLLOW STRUCTURAL SECTIONS
LIMIT STATE TABLES
q Summary of Tablesq SHEAR
q Load parallel to HSS longitudinal axisq WF Beam to Round, Rect, and Square HSS Columnq Single plate, Through plate, L, 2L, WT, Seated Conns
q AXIALq Load perpendicular to HSS longitudinal axisq Plate to Round and Rectangular/Square HSS Conns
q TRUSSq Branch HSS-to-Chord HSS Truss Connections in T/C
q MOMENTq Branches under IP or OOP Bending Moment to HSS
Chordsq Table Notes and Definition of Parameters
HSS HOLLOW STRUCTURAL SECTIONS
SUMMARY OF LIMIT STATES
HSS HOLLOW STRUCTURAL SECTIONS
RESOURCE - LIMIT STATE TABLE - SHEAR
STEELTUBEINSTITUTE 4/6/18
AISCSpecificationandManualReferences
AISC360-10and14thEd.Manualpp.
10-102to10-107
AISC360-16and15thEd.Manualpp.
10-87to10-91
AISC360-10and14thEd.Manualpp.10-102
to10-107
AISC360-16and15thEd.Manualpp.10-87
to10-91
AISC360-10and14thEd.Manualpp.10-132
to10-134
AISC360-16and15thEd.Manualpp.10-116
to10-119
AISC360-10and14thEd.Manualpp.10-7
to10-12
AISC360-16and15thEd.Manualpp.10-7
to10-12
AISC360-10and14thEd.Manualpp.
10-138to10-139
AISC360-16and15thEd.Manualpp.
10-123to10-124
AISC360-10and14thEd.Manualpp.10-84
to10-88
AISC360-16and15thEd.Manualpp.10-69
to10-73
AISC360-10and14thEd.Manualpp.10-93
to10-96
AISC360-16and15thEd.Manualpp.10-78to10-81and10-153
AISCManualConsiderationsSpecifictoHSSElements
14thEd.Manualpp.10-167
15thEd.Manualpp.10-153
14thEd.Manualpp.10-168
15thEd.Manualpp.10-154
14thEd.Manualpp.10-169
15thEd.Manualpp.10-155
14thEd.Manualpp.10-167
15thEd.Manualpp.10-152
SimilartoDoubleAngleConsiderationsperManualpp.10-167
SimilartoDoubleAngleConsiderationsperManualpp.10-152
14thEd.Manualpp.10-167
15thEd.Manualpp.10-153
14thEd.Manualpp.10-168
15thEd.Manualpp.10-153
Wallslenderness Manualpp.10-167 Manualpp.10-153 Manualpp.10-168 Manualpp.10-154 _ _ _ _ _ _ _ _Manualpp.10-168forverticalstiffenerplate
Manualpp.10-153forverticalstiffenerplate
HSSShearRuptureatWeld
HSSShearYieldingatWeld _ _ _ _ _ _ _ _ _ _ _ _
HSSPunchingShear
SpecEq.(K1-3)
subjecttolimitsinTableK1.1AorTableK1.2A
ManualEq.(10-7) _ _ _ _ _ _ _ _ _ _
SpecEq.(K1-3)
subjecttolimitsinTableK1.1AorTableK1.2A
ManualEq.(10-7)atverticalstiffenerplate
Yieldlineplasticity _ _ _ _ _ _ _ _ _ _ _ _ Manualpp.10-168andTable10-15
Manualpp.10-153andTable10-15
AdditionalHSSProvisions _ _ _ _
GuidelinesforweldatHSScolumnworkableflatdimensionsperManual
pp.10-169
GuidelinesforweldatHSScolumnworkableflatdimensionsperManual
pp.10-155
GuidelinesforweldtoHSScolumnworkableflatdimensionsperManual
pp.10-167
GuidelinesforweldtoHSScolumnworkableflatdimensionsperManual
pp.10-152
SimilartoDoubleAngleConsiderationsperManualpp.10-167
SimilartoDoubleAngleConsiderationsperManualpp.10-152
_ _
ManualEq.(9-2),andDG24Eq.(2-4)
ManualEq.(9-2),andDG24Eq.(2-4)
DG24Eq.(2-3)
ManualTable10-15
HSSColumn
ManualEq.(9-2),andDG24Eq.(2-4)
ManualEq.(9-2),andDG24Eq.(2-4)
ManualEq.(9-2),andDG24Eq.(2-4)
ManualEq.(9-2),andDG24Eq.(2-4)
ManualEq.(9-2),andDG24Eq.(2-4)
UnstiffenedSeat StiffenedSeat
LIMITSTATETABLEPERAISCSPECIFICATION360-16ANDTHE15THEDITIONSTEELCONSTRUCTIONMANUAL
Element
LimitState
SHEARLOADPARALLELTOHSSLONGITUDINALAXIS
WFBeamConnectionstoRound,Rectangular,andSquareHSS
SinglePlate(ConventionalandExtendedConfigurations)
ThroughPlate SingleAngle DoubleAngle WT
STEELTUBEINSTITUTE 4/6/18
AISCSpecificationandManualReferences
AISC360-10and14thEd.Manualpp.
10-102to10-107
AISC360-16and15thEd.Manualpp.
10-87to10-91
AISC360-10and14thEd.Manualpp.10-102
to10-107
AISC360-16and15thEd.Manualpp.10-87
to10-91
AISC360-10and14thEd.Manualpp.10-132
to10-134
AISC360-16and15thEd.Manualpp.10-116
to10-119
AISC360-10and14thEd.Manualpp.10-7
to10-12
AISC360-16and15thEd.Manualpp.10-7
to10-12
AISC360-10and14thEd.Manualpp.
10-138to10-139
AISC360-16and15thEd.Manualpp.
10-123to10-124
AISC360-10and14thEd.Manualpp.10-84
to10-88
AISC360-16and15thEd.Manualpp.10-69
to10-73
AISC360-10and14thEd.Manualpp.10-93
to10-96
AISC360-16and15thEd.Manualpp.10-78to10-81and10-153
AISCManualConsiderationsSpecifictoHSSElements
14thEd.Manualpp.10-167
15thEd.Manualpp.10-153
14thEd.Manualpp.10-168
15thEd.Manualpp.10-154
14thEd.Manualpp.10-169
15thEd.Manualpp.10-155
14thEd.Manualpp.10-167
15thEd.Manualpp.10-152
SimilartoDoubleAngleConsiderationsperManualpp.10-167
SimilartoDoubleAngleConsiderationsperManualpp.10-152
14thEd.Manualpp.10-167
15thEd.Manualpp.10-153
14thEd.Manualpp.10-168
15thEd.Manualpp.10-153
Wallslenderness Manualpp.10-167 Manualpp.10-153 Manualpp.10-168 Manualpp.10-154 _ _ _ _ _ _ _ _Manualpp.10-168forverticalstiffenerplate
Manualpp.10-153forverticalstiffenerplate
HSSShearRuptureatWeld
HSSShearYieldingatWeld _ _ _ _ _ _ _ _ _ _ _ _
HSSPunchingShear
SpecEq.(K1-3)
subjecttolimitsinTableK1.1AorTableK1.2A
ManualEq.(10-7) _ _ _ _ _ _ _ _ _ _
SpecEq.(K1-3)
subjecttolimitsinTableK1.1AorTableK1.2A
ManualEq.(10-7)atverticalstiffenerplate
Yieldlineplasticity _ _ _ _ _ _ _ _ _ _ _ _ Manualpp.10-168andTable10-15
Manualpp.10-153andTable10-15
AdditionalHSSProvisions _ _ _ _
GuidelinesforweldatHSScolumnworkableflatdimensionsperManual
pp.10-169
GuidelinesforweldatHSScolumnworkableflatdimensionsperManual
pp.10-155
GuidelinesforweldtoHSScolumnworkableflatdimensionsperManual
pp.10-167
GuidelinesforweldtoHSScolumnworkableflatdimensionsperManual
pp.10-152
SimilartoDoubleAngleConsiderationsperManualpp.10-167
SimilartoDoubleAngleConsiderationsperManualpp.10-152
_ _
ManualEq.(9-2),andDG24Eq.(2-4)
ManualEq.(9-2),andDG24Eq.(2-4)
DG24Eq.(2-3)
ManualTable10-15
HSSColumn
ManualEq.(9-2),andDG24Eq.(2-4)
ManualEq.(9-2),andDG24Eq.(2-4)
ManualEq.(9-2),andDG24Eq.(2-4)
ManualEq.(9-2),andDG24Eq.(2-4)
ManualEq.(9-2),andDG24Eq.(2-4)
UnstiffenedSeat StiffenedSeat
LIMITSTATETABLEPERAISCSPECIFICATION360-16ANDTHE15THEDITIONSTEELCONSTRUCTIONMANUAL
Element
LimitState
SHEARLOADPARALLELTOHSSLONGITUDINALAXIS
WFBeamConnectionstoRound,Rectangular,andSquareHSS
SinglePlate(ConventionalandExtendedConfigurations)
ThroughPlate SingleAngle DoubleAngle WT
HSS HOLLOW STRUCTURAL SECTIONS
RESOURCE – LIMIT STATE TABLE - AXIAL
HSS HOLLOW STRUCTURAL SECTIONS
RESOURCE – LIMIT STATE TABLE - TRUSS
HSS HOLLOW STRUCTURAL SECTIONS
LIMIT STATE TABLE -MOMENT
HSS HOLLOW STRUCTURAL SECTIONS
§ Although end distance is mentioned in a few tables in Chapter K, it should be considered for each individual limit state.
§ STI resource is available to guide for rectangular sections:§ https://steeltubeinstitute.org/hss/2017/05/31/rectangul
ar-hss-connections-close-chord-end/
A WORD ON END DISTANCES
HSS HOLLOW STRUCTURAL SECTIONS
LIMIT STATE TABLE: END DISTANCES
HSS HOLLOW STRUCTURAL SECTIONS
q General Provisions & Parameters for HSS Connections
q Effective Width Formula, Be
AISC 360-16, SECTION K1
= Bep= beoi
From 360-10
HSS HOLLOW STRUCTURAL SECTIONS
LIMIT STATE TABLE: EFFECTIVE WIDTH
HSS HOLLOW STRUCTURAL SECTIONS
5
solutionforsuchacombinedfailuremechanismbut itwastoocomplex forroutinedesignanddesign
recommendations have opted instead for discrete individual limit state checks. Importantly though,
DaviesandPacker(1982)showedthattheformulationtocaptureLocalyieldingofthebranchplate,Eqn.(K1-7),representedalowerboundtoboththeircombinedplastification-and-punchingmechanismaswell
asexperimentalresults,furthersubstantiatingthediscussionaboveregardingthesethreefailuremodes.
Figure4:Atension-loaded,transversebranchplateconnectionexhibitingthreefailuremechanisms:(i)
PlastificationoftheHSSface;(ii)PunchingshearoftheHSSconnectingface;(iii)LocalyieldingofHSSsidewalls
4.LocalyieldingofHSSsidewalls. Thislimitstate,showninFigure4,canoccurwiththebranchplateloadedineithertensionor
compressionwhenβiscloseto1.0.ItismanifestedbyyieldingofthetwoHSSsidewalls,orwebs,along
ashortdispersed load lengthdirectlybeneaththebranchplate. If the load isdispersedfroman initial
bearing length to the bottomof theHSS corner radius (analogous to dispersion to the k-line in aW-
section),atadispersionslopeof2.5:1,thenthetotalavailableyieldstrengthforthetwowebsis
Rn=2Fyt(5k+tp), wherek=outsidecornerradius (K1-9)and(J10-2)
5.LocalcripplingofHSSsidewalls. This limitstate,pertainingtobranchcompression loadonly,coversbucklingfailureofthetwo
sidewallswhenβiscloseto1.0.Forasingleconcentratedforce,correspondingtoaplate-to-HSST-
LIMIT STATE: HSS PUNCHING
Packer, 2015
HSS HOLLOW STRUCTURAL SECTIONS
LIMIT STATE: HSS PUNCHING
HSS HOLLOW STRUCTURAL SECTIONS
Section J10.10 Transverse Forces on Plate Elements
Page 9-14 “Plate Elements Subjected to Out-of-Plane Loads”
R2 = 0.60F7t9 2c;<< + 2L (15th Ed. Manual, Eq. 9-29)
LIMIT STATE: HSS PUNCHING
HSS HOLLOW STRUCTURAL SECTIONS
LIMIT STATE TABLE:PUNCHING
HSS HOLLOW STRUCTURAL SECTIONS
LIMIT STATE: HSS PLASTIFICATION
Packer, 2015
HSS HOLLOW STRUCTURAL SECTIONS
LIMIT STATE: HSS PLASTIFICATION
HSS HOLLOW STRUCTURAL SECTIONS
Section J10.10 Transverse Forces on Plate Elements refers to Section J4.5
Flexural yield-line mechanism must be derived.
Page 9-16 “For out-of-plane transverse loads”
LIMIT STATE: HSS PLASTIFICATION
HSS HOLLOW STRUCTURAL SECTIONS
LIMIT STATE: HSS PLASTIFICATION
360-10, K2. HSS-to-HSS Truss Connections
360-16, Equation (9-30)
𝑎 ≠ 𝑏15
thEd
Man
ual,
Fig.
9-5
(a)
HSS HOLLOW STRUCTURAL SECTIONS
LIMIT STATE TABLE:HSS PLASTIFICATION
HSS HOLLOW STRUCTURAL SECTIONS
5
solutionforsuchacombinedfailuremechanismbut itwastoocomplex forroutinedesignanddesign
recommendations have opted instead for discrete individual limit state checks. Importantly though,
DaviesandPacker(1982)showedthattheformulationtocaptureLocalyieldingofthebranchplate,Eqn.(K1-7),representedalowerboundtoboththeircombinedplastification-and-punchingmechanismaswell
asexperimentalresults,furthersubstantiatingthediscussionaboveregardingthesethreefailuremodes.
Figure4:Atension-loaded,transversebranchplateconnectionexhibitingthreefailuremechanisms:(i)
PlastificationoftheHSSface;(ii)PunchingshearoftheHSSconnectingface;(iii)LocalyieldingofHSSsidewalls
4.LocalyieldingofHSSsidewalls. Thislimitstate,showninFigure4,canoccurwiththebranchplateloadedineithertensionor
compressionwhenβiscloseto1.0.ItismanifestedbyyieldingofthetwoHSSsidewalls,orwebs,along
ashortdispersed load lengthdirectlybeneaththebranchplate. If the load isdispersedfroman initial
bearing length to the bottomof theHSS corner radius (analogous to dispersion to the k-line in aW-
section),atadispersionslopeof2.5:1,thenthetotalavailableyieldstrengthforthetwowebsis
Rn=2Fyt(5k+tp), wherek=outsidecornerradius (K1-9)and(J10-2)
5.LocalcripplingofHSSsidewalls. This limitstate,pertainingtobranchcompression loadonly,coversbucklingfailureofthetwo
sidewallswhenβiscloseto1.0.Forasingleconcentratedforce,correspondingtoaplate-to-HSST-
LIMIT STATE: LOCAL YIELDING OF HSS SIDEWALLS
Packer, 2015
HSS HOLLOW STRUCTURAL SECTIONS
AISC 360-16 Section J10.2 – Web Local Yielding
R2 = F7BtB 5k + lE (J10-2)tw = 2* tdes (design thickness of 2 HSS walls)
LIMIT STATE: LOCAL YIELDING OF HSS SIDEWALLS
HSS HOLLOW STRUCTURAL SECTIONS
LIMIT STATE TABLE:HSS SIDEWALL YIELDING
HSS HOLLOW STRUCTURAL SECTIONS
6
connection, the available strength differs from internationalHSS connection recommendations and isadaptedbyAISCfromtheweblocalcripplingexpressionforaW-sectionweb: Rn=1.6t2[1+3tp/(H–3t)][EFy]0.5Qf (K1-10)and(J10-4)Similarly,forapairofconcentratedforces,correspondingtoaplate-to-HSSCross-(orX-)connection(seeFigure 5), the available strength differs from international HSS connection recommendations and isadaptedbyAISCfromtheweblocalbucklingexpressionforaW-sectionweb: Rn=[48t3/(H–3t)][EFy]0.5Qf (K1-11)and(J10-8)
Figure5:BucklingofHSSsidewallsundertransversecompression
LimitsofApplicability TableK1.2AofAISC360-10givesarangeofvalidityforanumberofgeometricandmechanicalpropertiesforwhichallofTableK1.2wouldbevalid.AlllimitswouldnotapplytoallthelimitstatesinTableK1.2.Fortransverseplateconnections,Eqns.(K1-7)and(K1-8),correspondingtoLimitStates2and3 above, contain effective width terms which have been derived from research – predominantlyexperimental–inwhichthewallslendernesslimits(B/tandH/t≤35)andwidthratio(1.0≥Bp/B≥0.25)representedtheboundsofthetestdataatthetime.Similarly,themechanicalpropertylimitationsalsorepresentedthelimitsoftestevidenceforLimitStates2and3,atthetime.Asnotedpreviously,LimitState1isagenericanalyticalsolution.LimitState4isverysimilartointernationalrecommendationsandisfundamentaltomoststeeldesignstandards.LimitState5availablestrengthexpressions(andtheir
LIMIT STATE: LOCAL CRIPPLING/BUCKLING OF HSS SIDEWALLS
HSS HOLLOW STRUCTURAL SECTIONS
AISC 360-16 Section J10.3 (Web Local Crippling)
AISC 360-16 Section J10.5 (Web Compression Buckling)
LIMIT STATE: LOCAL CRIPPLING/BUCKLING OF HSS SIDEWALLS
HSS HOLLOW STRUCTURAL SECTIONS
qt9 ≤GHGIJ
t (Eqn K1-3) based on relative strength of the HSS and the shear tab.
qSpecification Committee voted to base the check on the assumed demand moment due to beam reaction and move it out of the spec and into Part 10 of the Manual.
SHEAR TAB CONNECTION
HSS HOLLOW STRUCTURAL SECTIONS
qAs long as HSS walls are classified as not slender, the distortion of the wall is insignificant to the column strength.
qPlastification doesn’t control.qOnly check punching shear (shear rupture).
qRKe ≤MGHNOJP
Q (Manual Eq.10-7a)
SHEAR TAB CONNECTION
HSS HOLLOW STRUCTURAL SECTIONS
LIMIT STATE TABLE:SHEAR TAB
HSS HOLLOW STRUCTURAL SECTIONS
CAP PLATE CONNECTION
Cap Plate – For Round and Rectangular HSS360-16 Section J10.2 – Web Local YieldingR2 = F7BtB 5k + lE (J10-2)
tw = 2* tdes
k = tp (cap plate thickness)lb = b (t of connecting plate)
AISC 360-10
R2 = 2F7tR;S 5𝑡U + b AISC 360-10
HSS HOLLOW STRUCTURAL SECTIONS
Cap Plate – For Round and Rectangular HSSIf 5𝑡U + b ≥ B → 𝑅# = 𝐹[A
All 4 sides are engagedCap plate needs to be of sufficient thickness
CAP PLATE CONNECTION
HSS HOLLOW STRUCTURAL SECTIONS
LIMIT STATE TABLE:CAP PLATE CONNECTION
HSS HOLLOW STRUCTURAL SECTIONS
A NOTE ABOUT Qf
q Main member stress functionq Reduces the local strength at the connectionq For rounds 0.4 ≤ Q< ≤ 1.0
q Q< = 1 for HSS in tensionq Q<= 1.0 – 0.3U(1+U) for HSS in compression (K2-3)
q where U = `abGcde
+ fabGcg
(K2-4)q (side with lower compression)
HSS HOLLOW STRUCTURAL SECTIONS
A NOTE ABOUT Qf
q For rectangles 0.5 ≤ Q< ≤ 1.0q Q< = 1 for HSS in tensionq 𝑄i = 1.3 − 0.4 k
l≤ 1.0 for T-, Y-, X- conn (K3-14)
q 𝑄i = 1.3 − 0.4 klmnn
≤ 1.0 for gapped K- conn (K3-15)
q where U = `abGcde
+ fabGcg
(K2-4)
q (side with higher compression)
HSS HOLLOW STRUCTURAL SECTIONS
RESOURCE – LIMIT STATE TABLE
q https://steeltubeinstitute.org/hss/hss-information/aisc-360-16/
HSS HOLLOW STRUCTURAL SECTIONS
§ Next month’s webinar expands on this through worked design examples.
§ STI’s Design Manuals Volumes 3 & 4 – available by April, 2020
§ AISC’s Design Guide 24 is currently being updated (expected late 2020)
§ Steelwise by Carlo Lini, Modern Steel Construction, June 2019
ADDITIONAL RESOURCES
HSS HOLLOW STRUCTURAL SECTIONS
§ STI’s Limit State Tables are…a) Free to AISC membersb) Free to AARP membersc) Free if you know the secret handshaked) Free to everyone
POLLING QUESTION 1
HSS HOLLOW STRUCTURAL SECTIONS
§Do you want a PDH certificate for this webinar? a) Yesb) No
POLLING QUESTION 2
NAVIGATING AISC 360-16 HSS CONNECTION
DESIGN: LIMIT STATE TABLES
PRESENTED BY CATHLEEN JACINTO, SE, PEFORSE CONSULTING, LLC