ERRATA For AASHTO LRFD Bridge Design Specifications, 8th .

Summary of Errata Changes for LRFD-8, May 2018Page6-259Existing TextCorrected TextFigure C6.13.6.1.3c-1Aw Figure C6.13.6.1.3c-1tD t haunch s22Aw HwtD t haunch s22HwPfy Fyf AePfy Fyf AetsAw D2 thaunch 2HwWeb Moment H w AwHw 6-259C6.13.6.1.3cC6.13.6.1.3c Figure C6.13.6.1.3c-2 illustrates the computationof the horizontal force in the web, Hw, where necessaryfor composite sections subject to negative flexure andnoncomposite sections, taken as the portion of thefactored moment at the strength limit state that exceedsthe moment resistance provided by the flange splicesdivided by the moment arm, Aw, to the mid-thickness ofthe top or bottom flange, whichever flange has thelarger value of Pfy:5 of 11Web MomentAwFigure C6.13.6.1.3c-2 illustrates the computation of thehorizontal force in the web, Hw, where necessary forcomposite sections subject to negative flexure andnoncomposite sections,. The web moment is again taken asthe portion of the factored moment at the strength limit statethat exceeds the moment resistance provided by the flangesplices. In this case, however, Hw is taken as the webmoment divided by D/4, as shown in Figure C6.13.6.1.3c2.the moment arm, Aw, to the mid-thickness of the top orbottom flange, whichever flange has the larger value of Pfy:

Summary of Errata Changes for LRFD-8, May 2018Page6-259Existing TextCorrected TextFigure C6.13.6.1.3c-2Figure C6.13.6.1.3c-2HwHwD tfAw 22Aw Largest flangeforce Pfy FyfAeD tf 22Largest flangeforce Pfy FyfAeHw2D2D2Hw2D2Web Moment Hw 6 of 11Hw D 2 2 Web MomentD/4

Summary of Errata Changes for LRFD-8, May 2018Page6-2598-8(Editorial)10-7610-7710-78Existing TextC6.13.6.1.3cCorrected TextC6.13.6.1.3c.Because the resultant web force in cases where Hwis computed is divided equally to all of the bolts in thisapproach, the traditional vector analysis for bolt groupssubject to a concentric shear and a centroidal momentis not applied.Table 8.4.1.1.4-1The required moment resistance in the web for the caseshown in Figure C6.13.6.1.3c-1 is provided by a horizontaltensile force, Hw, assumed acting at the mid-depth of theweb that is equilibrated by an equal and opposite horizontalcompressive force in the concrete deck. The requiredmoment resistance in the web for the case shown in FigureC6.13.6.1.3c-2 is provided by two equal and oppositehorizontal tensile and compressive forces, Hw/2, assumedacting at a distance D/4 above and below the mid-height ofthe web. In each case, there is no net horizontal force actingon the section.Because the resultant web force in cases where Hw iscomputed is divided equally to all of the bolts in thisapproach, the traditional vector analysis for bolt groupssubject to a concentric shear and a centroidal moment isnot applied.Table 8.4.1.1.4-1Douglas Fir-larchEq. C10.6.3.1.2e-5Douglas Fir-LarchEq. C10.6.3.1.2e-5Bβm 4HBβm 4H s 2Eq. C10.6.3.1.2e-6Eq. C10.6.3.1.2e-6Bβm 2HBβm 2H s 2Eq. 10.6.3.1.2f-1Eq. 10.6.3.1.2f-1 1 Kqn q2 B H 2 1 L K tan φ′1 B 1 c1′ cot φ1′ e K c1′ cot φ1′ B Hs 2 B 2 1 K tan φ′1 1 c1′ cot φ1′ e L K qn q2 1 c1′ cot φ1′ K (Note: in the new version, the H B term in theexponent has been changed to HB .)s2 10-78Eq. C10.6.3.1.2f-1q n q2 e Eq. C10.6.3.1.2f-1 B H L B0.67 1 q n q2 e B H s 2 L B0.67 1 (Note: in the new version, the H B exponent has been changed to HB .)s2 7 of 11 term in the

Summary of Errata Changes for LRFD-8, May ting Text Article C5.6.4.1 notes that compressionmembers are usually prestressed only where they aresubjected to high levels of flexure. Therefore, amethod of determining nominal axial compressionresistance is not given.11.3.1—GeneralhaCorrected TextC10.7.3.13.2distance between the base of the wall, orthe mudline in front of the wall, and theresultant active seismic earth pressureforce (ft) (A11.3.1) Article C5.6.4.1 notes that Compression membersare usually prestressed only where they are subjected tohigh levels of flexure. Therefore, a method of determiningnominal axial compression resistance is not given.11.3.1—Generalha distance between the base of the wall, or themudline in front of the wall, and the resultantactive seismic earth pressure force (ft)(A11.3.1)C11.9.5.1C11.9.5.1 A number of suitable methods for thedetermination of anchor loads are in common use.Sabatini et al. (1999) provides two methods which canbe used: the Tributary Area Method, and the HingeMethod. These methods are illustrated in FiguresC11.5.9.1-1 and C11.5.9.1-2. These figures assumethat the soil below the base of the excavation hassufficient strength to resist the reaction force R. If thesoil providing passive resistance below the base of theexcavation is weak and is inadequate to carry thereaction force R, the lowest anchor should be designedto carry both the anchor load as shown in the figuresas well as the reaction force. See Article 11.8.4.1 forevaluation of passive resistance. Alternatively, soilstructure interaction analyses, e.g., beam on elasticfoundation, can be used to design continuous beamswith small toe reactions, as it may be overlyconservative to assume that all of the load is carriedby the lowest anchor. A number of suitable methods for the determinationof anchor loads are in common use. Sabatini et al. (1999)provides two methods which can be used: the TributaryArea Method, and the Hinge Method. These methods areillustrated in Figures C11.5.9.1-1 C11.9.5.1-1 andC11.5.9.1-2 C11.9.5.1-2. These figures assume that thesoil below the base of the excavation has sufficientstrength to resist the reaction force R. If the soil providingpassive resistance below the base of the excavation is weakand is inadequate to carry the reaction force R, the lowestanchor should be designed to carry both the anchor load asshown in the figures as well as the reaction force. SeeArticle 11.8.4.1 for evaluation of passive resistance.Alternatively, soil-structure interaction analyses, e.g.,beam on elastic foundation, can be used to designcontinuous beams with small toe reactions, as it may beoverly conservative to assume that all of the load is carriedby the lowest anchor.8 of 11

Summary of Errata Changes for LRFD-8, May 2018Page11-49Existing TextFigure C11.9.5.1-2— Calculation of Anchor Loadsfor Multilevel Wall after Sabatini et al. (1999)TributaryAreaMethodHinge MethodT1 Load over length H1 H2/2T1 Calculated from ΣMC 0Corrected TextFigure C11.9.5.1-2— Calculation of Anchor Loads forMultilevel Wall after Sabatini et al. (1999)Tributary Area MethodT1 Load over length H1 H2/2T1 Calculated from ΣMC 0T2 Load over length H2/2 Hn/2T2u Total earth pressure (ABCGF) – T1T2 Load over length H2/2 Hn/2T2u Total earth pressure (ABCGF) – T1Tn Load over length Hn/2 Hn 1/2T2L Calculated from ΣMD 0Tn Load over length Hn/2 Hn 1/2T2L Calculated from ΣMD 0R Load over length Hn 1/2Tnu Total earth pressure (CDIH) – T2LR Load over length Hn 1/2Tnu Total earth pressure (CDIH) – T2LTnL Calculated from ΣME 0TnL Calculated from ΣME 0R Total earth pressure – T1 – T2 – TnR Total earth pressure – T1 – T2 – TnT2 T2u T2L T2 T2u T2LT2 T2u T2LTn Tnu TnLTn Tnu TnL9 of 11Hinge Method

Summary of Errata Changes for LRFD-8, May 2018Page11-79Existing Text11.10.6.4.2b 11-1233) Polymer Requirements: Polymers which arelikely to have good resistance to long-term chemicaldegradation shall be used if a single default reductionfactor is to be used, to minimize the risk of the occurrenceof significant long-term degradation. The polymermaterial requirements provided in Table 11.10.6.4.2b-1shall, therefore, be met if detailed product specific data asdescribed in AASHTO R 69 and Elias, et al. (2009) is notobtained. Polymer materials not meeting the requirementsin Table 11.10.6.4.2b-1 may be used if this detailedproduct specific data extrapolated to the design lifeintended for the structure are obtained.Eq. A11.5.2-3Eq. A11.5.2-3 k k 3.27log 1 log d 1.51 0.74log k k 0.80 0.80log(k ) 1.59log(PGV ) As yh0 h0Eq. A11.5.2-4 log d 1.31 0.93 log k y k 4.52log 1 y kh0 kh0 0.46log ( kh0 ) 1.12log( PGV )The kv term in the first parenthesis should be ky12.3—NOTATION yh0The kv term in the first parenthesis should be kyEq. A11.5.2-4 k k 1.31 0.93 log v 4.52 log 1 v log d kh 0 kh 0 0.46 log ( kh 0 ) 1.12 log ( PGV )12-2 3) Polymer Requirements: Polymers which arelikely to have good resistance to long-termchemical degradation shall be used if a singledefault reduction factor is to be used, to minimizethe risk of the occurrence of significant long-termdegradation. The polymer material requirementsprovided in Table 11.10.6.4.2b-1 shall, therefore,be met if detailed product specific data asdescribed in AASHTO R 69 and Elias, et al.(2009) is not obtained. Polymer materials notmeeting the requirements in Table 11.10.6.4.2b-1may be used if this detailed product specific dataextrapolated to the design life intended for thestructure are obtained. 1 ky k log d 1.51 0.74 log v 3.27 log kh 0 kh 011-123Corrected Text11.10.6.4.2b12.3—NOTATIONtension reinforcement area on crosssection width, b (in.2/ft) (C12.10.4.2.4a)(C12.11.4) (C12.11.5)10 of 11 As tension reinforcement area on cross-sectionwidth, b (in.2/ft) (C12.10.4.2.4a) (C12.11.4)(C12.11.5)

Summary of Errata Changes for LRFD-8, May 2018Page12-2914-24(Editorial)Existing TextCorrected ection Table A12-3 shall apply. Minimumrequirements for section properties shall be taken asspecified in Table 12.8.3.1.1-1. Covers that are lessthan that shown in Table 12.8.3.1-1 and thatcorrespond to the minimum plate thickness for a givenradius may be used if ribs are used to stiffen the plate.If ribs are used, the plate thickness may not be reducedbelow the minimum shown for that radius, and themoment of inertia of the rib and plate section shall notbe less than that of the thicker unstiffened platecorresponding to the fill height. Use of soil cover lessthan the minimum values shown for a given radiusshall require a special design. Table A12-3 shall apply. Minimum requirements forsection properties shall be taken as specified inTable 12.8.3.1.1-1. Covers that are less than that shown inTable 12.8.3.1-1 Table 12.8.3.1.1-1 and that correspond tothe minimum plate thickness for a given radius may beused if ribs are used to stiffen the plate. If ribs are used, theplate thickness may not be reduced below the minimumshown for that radius, and the moment of inertia of the riband plate section shall not be less than that of the thickerunstiffened plate corresponding to the fill height. Use ofsoil cover less than the minimum values shown for a givenradius shall require a special design.C14.5.6.9.2C14.5.6.9.2 The designer should consider showing the totalestimated transverse and vertical movement in eachdirection, as well as the rotation in each directionabout the three principal axes on the contract plans.Vertical movement due to vertical grade, withhorizontal bearings, and vertical movement due togirder and rotation may also be considered.11 of 11 The designer should consider showing the totalestimated transverse and vertical movement in eachdirection, as well as the rotation in each direction about thethree principal axes on the contract plans. Verticalmovement due to vertical grade, with horizontal bearings,and vertical movement due to girder and rotation may alsobe considered.

SECTION 2: GENERAL DESIGN AND LOCATION FEATURES2.3.2.2.2—Protection of UsersRailings shall be provided along the edges ofstructures conforming to the requirements of Section 13.All protective structures shall have adequate surfacefeatures and transitions to safely redirect errant traffic.In the case of movable bridges, warning signs, lights,signal bells, gates, barriers, and other safety devices shallbe provided for the protection of pedestrian, cyclists, andvehicular traffic. These shall be designed to operate beforethe opening of the movable span and to remain operationaluntil the span has been completely closed. The devicesshall conform to the requirements for “Traffic Control atMovable Bridges,” in the Manual on Uniform TrafficControl Devices (MUTCD) or as shown on plans.Where specified by the Owner, sidewalks shall beprotected by barriers.2-5C2.3.2.2.2Protective structures include those that provide a safeand controlled separation of traffic on multimodal facilitiesusing the same right-of-way.Special conditions, such as curved alignment, impededvisibility, etc., may justify barrier protection, even with lowdesign velocities.2.3.2.2.3—Geometric StandardsRequirements of the AASHTO publication A Policy onGeometric Design of Highways and Streets shall either besatisfied or exceptions thereto shall be justified anddocumented. Width of shoulders and geometry of trafficbarriers shall meet the specifications of the Owner.2.3.2.2.4—Road SurfacesRoad surfaces on a bridge shall be given antiskidcharacteristics, crown, drainage, and superelevation inaccordance with A Policy on Geometric Design ofHighways and Streets or local requirements.2.3.2.2.5—Vessel CollisionsBridge structures shall either be protected againstvessel collision forces by fenders, dikes, or dolphins asspecified in Article 3.14.15, or shall be designed towithstand collision force effects as specified inArticle 3.14.14.C2.3.2.2.5The need for dolphin and fender systems can beeliminated at some bridges by judicious placement of bridgepiers. Guidance on use of dolphin and fender systems isincluded in the AASHTO Highway Drainage Guidelines,Volume 7: Hydraulic Analyses for the Location and Design Permits for construction of a bridge over navigablewaterways shall be obtained from the U.S. Coast Guardand/or other agencies having jurisdiction. Navigationalclearances, both vertical and horizontal, shall beestablished in cooperation with the U.S. Coast Guard.C2.3.3.1Where bridge permits are required, early coordinationshould be initiated with the U.S. Coast Guard to evaluate theneeds of navigation and the corresponding location anddesign requirements for the bridge.Procedures for addressing navigational requirements forbridges, including coordination with the Coast Guard, areset forth in the Code of Federal Regulations, 23 CFR,Part 650, Subpart H, “Navigational Clearances for Bridges,”and 33 U.S.C. 401, 491, 511, et seq. 2018 by the American Association of State Highway and Transportation Officials.All rights reserved. Duplication is a violation of applicable law.

2-6AASHTO LRFD BRIDGE DESIGN SPECIFICATIONS, EIGHTH EDITION, 20172.3.3.2—Highway VerticalC2.3.3.2The vertical clearance of highway structures shall be inconformance with the AASHTO publication A Policy onGeometric Design of Highways and Streets for theFunctional Classification of the Highway or exceptionsthereto shall be justified. Possible reduction of verticalclearance, due to settlement of an overpass structure, shallbe investigated. If the expected settlement exceeds 1.0 in.,it shall be added to the specified clearance.The vertical clearance to sign supports and pedestrianoverpasses should be 1.0 ft. greater than the highwaystructure clearance, and the vertical clearance from theroadway to the overhead cross bracing of through-trussstructures should not be less than 17.5 ft.The specified minimum clearance should include 6.0 in.for possible future overlays. If overlays are notcontemplated by the Owner, this requirement may benullified.Sign supports, pedestrian bridges, and overhead crossbracings require the higher clearance because of their lesserresistance to impact.2.3.3.3—Highway HorizontalC2.3.3.3The bridge width shall not be less than that of theapproach roadway section, including shoulders or curbs,gutters, and sidewalks.Horizontal clearance under a bridge should meet therequirements of Article 2.3.2.2.1.No object on or under a bridge, other than a barrier,should be located closer than 4.0 ft. to the edge of adesignated traffic lane. The inside face of a barrier shouldnot be closer than 2.0 ft. to either the face of the object orthe edge of a designated traffic lane.The usable width of the shoulders should generally betaken as the paved width.The specified minimum distances between the edge ofthe traffic lane and fixed object are intended to preventcollision with slightly errant vehicles and those carryingwide loads.2.3.3.4—Railroad OverpassC2.3.3.4Structures designed to pass over a railroad shall be inaccordance with standards established and used by theaffected railroad in its normal practice. These overpassstructures shall comply with applicable federal, state,county, and municipal laws.Regulations, codes, and standards should, as aminimum, meet the specifications and design standards ofthe American Railway Engineering and Maintenance ofWay Association (AREMA), the Association of AmericanRailroads, and AASHTO.Attention is particularly called to the following chaptersin the Manual for Railway Engineering (AREMA, 2003): Chapter 7—Timber Structures,Chapter 8—Concrete Structures and Foundations,Chapter 9—Highway-railroad Crossings,Chapter 15—Steel Structures, andChapter 18—Clearances.The provisions of the individual railroads and theAREMA Manual should be used to determine: -clearances,loadings,pier protection,waterproofing, andblast protection.LRFD-8-E1: May 2018 Errata toAASHTO LRFD Bridge Design Specifications, 8th Edition 2018 by the American Association of State Highway and Transportation Officials.All rights reserved. Duplication is a violation of applicable law.

SECTION 4: STRUCTURAL ANALYSIS AND EVALUATIONncf PPDPePuPwppe pe(x) poR RdrS SbSMsTTGTHTmTSTuTUGt tg totsVLD VLLVLUvs(x)vs,MAXW WeW1 ww(x) wpwg XXextx 4-9minimum number of intermediate cross-frames or diaphragms within the individual spans of the bridgeor bridge unit at the stage of construction being evaluated (4.6.3.3.2)axle load (kip) (4.6.2.1.3)design horizontal wind pressure (ksf) (C4.6.2.7.1)Euler buckling load (kip) (4.5.3.2.2b)factored axial load (kip) (4.5.3.2.2b) (4.7.4.5)lateral wind force applied to the brace point (kips) (C4.6.2.7.1)tire pressure (ksi) (4.6.2.1.8)equivalent uniform static seismic loading per unit length of bridge that is applied to represent th

AASHTO LRFD Bridge Design Specifications, 8th Edition (LRFD-8) May 2018 . Dear Customer: Recently, we were made aware of some technical revisions that need to be applied to the AASHTO LRFD Bridge Design Specifications, 8th Edition. Please scroll down to see the full erratum.File Size: 2MB