LRFD Bridge Design Manual. Bridge Office MINNESOTA DEPARTMENT OF TRANSPORTATION MANUAL

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2 MANUAL MINNESOTA DEPARTMENT OF TRANSPORTATION Bridge Office LRFD Bridge Design Manual

3 MnDOT BRIDGE OFFICE LRFD Bridge Design Manual Minnesta Department f Transprtatin 3485 Hadley Avenue Nrth Mail Stp 610 Oakdale, MN Phne: 651/ Fax: 651/ JULY 2003 OCTOBER 2003 JANUARY 2004 APRIL 2004 OCTOBER 2004 DECEMBER 2004 FEBRUARY 2005 MARCH 2005 NOVEMBER 2005 MARCH 2006 APRIL 2006 MAY 2006 AUGUST 2006 OCTOBER 2006 FEBRUARY 2007 JUNE 2007 JULY 2007 OCTOBER 2007 APRIL 2008 MAY 2008 JUNE 2008 AUGUST 2008 SEPTEMBER 2008 OCTOBER 2008 APRIL 2009 MAY 2009 OCTOBER 2009 MARCH 2010 JUNE 2010 DECEMBER 2010 JUNE 2011 SEPTEMBER 2011 OCTOBER 2011 DECEMBER 2011 APRIL 2012 NOVEMBER 2012 APRIL 2013 SEPTEMBER 2013 FEBRUARY 2014 JULY 2014 AUGUST 2014 DECEMBER 2014 MAY 2015 JUNE 2015 AUGUST 2015 MAY 2016 JULY 2016 AUGUST 2016 DECEMBER 2016 MARCH 2017

4 JULY 2016 LRFD BRIDGE DESIGN xi 14.6 Sle Plate Design (Steel Beams) Tables Design Examples Fixed Elastmeric Bearing Design Example Expansin Elastmeric Bearing Design Example BRIDGE LOAD RATING General Analysis Cmputer Prgrams Refined Analysis Lads Rating Equatin Factrs Rating New Bridges Re-rating Existing Bridges Substructures Nn-Standard Bridge Types Timber Bridges Culverts Gusset Plates Lad Testing Lad Psting General Rating Factrs fr Psting Overweight Permits Physical Inspectin Rating (PIR) Frms and Dcumentatin Submittal / Filing APPENDIX 15-A: GLOSSARY APPENDIX 15-B: RATING FORMS APPENDIX 15-C: OVERWEIGHT PERMIT RESTRICTIONS FOR BRIDGES APPENDIX 15-D: MINNESOTA LEGAL (POSTING) LOADS APPENDIX 15-E: MINNESOTA STANDARD PERMIT TRUCKS G

5 MARCH 2017 LRFD BRIDGE DESIGN xii APPENDIX 15-F: MINNESOTA STANDARD PERMIT TRUCKS G APPENDIX A. MEMOS # REMOVED # REMOVED # REMOVED # REMOVED # REMOVED # Adhesive Anchrs Under Sustained Tensile Lads... (dated Oct. 3, 2007) # REMOVED # Prestressed Cncrete Design Calculatin f Prestress Lsses and Beam Camber & Deflectin...(dated Sept. 18, 2008) # Truss Bridge Gusset Plate Analysis... (dated Oct. 20, 2008) # REMOVED # REMOVED # Interim Guidance fr Installatin f Temprary Barriers n Bridges and Apprach Panels... (dated December 23, 2011) # Discntinued Usage f Plain Elastmeric Bearing Pads and Substitutin with Cttn-Duck Bearing Pads...(dated April 12, 2012) # Transitin t New MnDOT Pile Frmula 2012 (MPF12)...(dated Nvember 21, 2012) # Cnversin frm Metric t U.S. Cust. Rebar Designatins...(dated April 17, 2013) # AASHTO LRFD Article Cncrete Crack Cntrl Check (dated August 6, 2014) # Inclusin f Infrmatinal Quantities in Bridge Plans (dated December 23, 2014) # Cncrete Mix Design Designatins... (dated August 10, 2015) # Single Slpe Barrier (Type S) Bridge Standards(dated December 09, 2016) # Edge-f-Deck Thickness n Bridges and Wall Cping Height (dated March 28, 2017)

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8 These changes result in the fllwing revisins t previus guidance fund in the Mem t Designers ( ): 1) In the guidance regarding plumb vs. perpendicular barrier placement, the 5 th bullet as well as Figures 2, 3, and 4 f Mem t Designers ( ) called fr a level deck surface beneath the barrier. Fr decks that include a cncrete wearing curse, the tp f deck under the barrier will nt be level, but will slpe as shwn abve in Figure 1 f this Mem t Designers. Hwever, the barrier rientatin will still remain plumb r perpendicular as defined in the previus mem. 2) Fr the deck verhang design, the net effect f the edge f deck change fr decks that include a cncrete wearing curse is t reduce the deck thickness at the gutter line. Therefre, the entire sectin regarding deck verhang design is superceded by the fllwing: Deck Overhang Design Deck verhang requirements are dependent n the verhang length and verhang lcatin alng the bridge. Fr deck verhangs (measured frm centerline f beam t edge f deck) f up t 40% f the beam spacing that carry a Type S barrier, the BDM deck reinfrcement Tables and may be used fr the interir verhang regins. Fr the exterir verhang regins (applies t regins where the lngitudinal barrier reinfrcement is discntinuus, such as end f bridge jints and expansin jints), the fllwing mdificatins t the verhang reinfrcement are necessary t meet NCHRP 350 Test Level 4 (TL 4). Nte that the mdificatins nly apply when the gutter line is lcated utside the edge f the fascia beam flange. Fr cases where the gutter line is lcated inside the edge f the fascia beam flange, prvide reinfrcement per the BDM deck reinfrcement Tables and with n mdificatin. Fr a 36 Type S barrier n a deck with wearing curse supprted by steel beams spaced greater than 12 feet apart, prvide tp transverse hked #5 bars at 6 spacing ver a distance f 8 feet frm the jint. Lap these bars t the tp transverse #6 bars at 6 called fr by Table Include 180 degree standard hks n the edge f deck ends f the #5 bars. Fr all ther cases with a 36 Type S barrier, prvide #5 bars at 5 spacing r A s = 0.74 in 2 /ft fr the tp transverse bars ver a distance f 8 feet frm the jint. Include 180 degree standard hks n the edge f deck ends f these bars. This can be accmplished either by prviding hked verhang bars that splice t the main transverse deck bars r by prviding hked transverse bars that run frm edge t edge f the deck. Fr the 42 Type S, where the deck cnsists f a 9 mnlithic slab r a 7 structural slab plus a 2 cncrete wearing curse, include 180 degree standard hks n the edge f deck ends f the tp transverse bars ver a distance f 9 feet frm the jint. This can be accmplished either by prviding hked verhang bars that splice t the main transverse deck bars r by prviding hked transverse bars that run frm edge t edge f the deck. 3

9 Fr the 54 Type S, n mdificatin is needed. Prvide reinfrcement per the BDM deck reinfrcement Tables and Prvide an edge f deck thickness that is equal t the deck thickness specified in BDM Tables and fr all cases (typically 9, except fr wide beam spacings). When edge f deck thicknesses are greater than 9, adjust the wingwall cping height t match the edge f deck thickness. Where the wingwall ties int a retaining wall, crdinate with the radway designer as needed t set the retaining wall cping height t als match the edge f deck thickness. Fr deck verhangs that require a special design, use the fllwing guidance fr checking the extreme event limit state. Design cllisin lads F cdes and M cdes will be needed t cmplete the deck verhang design. Fr each barrier height H, values fr L c, M c, and R w have been determined using the yield line methd fund in AASHTO LRFD Spec. Article A The TL 4 value f 54 kips fr F t was adjusted fr the difference between the barrier height and height f F t applicatin. Then 4/3 F t was cmpared t R w, and the smaller value distributed ver L c + H fr end regins and L c + 2H fr interir regins. Als, M c was adjusted when 4/3 F t gverned. The results are the mments M cadj and tensin frces F cadj given in Table 1 belw. 36" Type S 42" Type S 54" Type S Exterir Interir Exterir Interir Exterir Interir M cadj (k ft/ft) F cadj (k/ft) Table 1 In rder t use these values, translate the mment M cadj at the tp f the deck t a mment M cdes lcated at the center f the deck using the fllwing methd (refer t Figure 2): e = M cadj / F cadj F cdes = F cadj Fr mnlithic decks: M cdes = F cdes (e t deck ) Fr decks cnsisting f structural slab plus wearing curse: M cdes = F cdes (e t str slab ) 4

10 Figure 2 Use the tensin frce F cdes and mment M cdes as the cllisin lads fr the deck verhang design. Revisin f the edge f deck thickness and cping height per this mem is t begin immediately fr all new preliminary bridge plans. If yu have any questins, please cntact Dave Dahlberg (dave.dahlberg@state.mn.us r (651) ) r me. cc: Kevin Western Dave Dahlberg Dave Cnkel/Lcal Bridge Design Cnsultants Clleen Lichtsinn/Bridge Design Cnsultants 5