the u.s. departments of transportation adopted the aashto lrfd bridge design specifications during the year 2007, which is mandated by aashto and fhwa. the application of lrfd specification initiated numerous research works in this field. this investigation addresses the lrfd and standard design methodologies of concrete deck slab, deck overhang, barrier and combined barrier-bridge overhang.
does not typically control deck design ca article c.3 . extreme event limit state most bridge decks include an overhang with a concrete barrier attached. therefore, the deck overhang has to be designed to meet the requirements for extreme event ii. the aashto 2012 requires bridge deck overhangs to be
3.2.1 lrfd deck design . a standard deck is defined as a deck slab on longitudinal beams with main reinforcement placed perpendicular to traffic. as outlined in article 9.6.1, the aashto lrfd code permits three methods or procedures for designing bridge decks with primary reinforcement perpendicular to the main bridge beams.
detailed updates deck overhang design 5/17/2017 bridge office mndot.gov/bridge 2. old practice 5/17/2017 bridge office mndot.gov/bridge 3 special design example for deck with a 7 structural slab plus 2 wearing course:
this example illustrates the design of a two span precast prestressed i-girder bridge. the bridge has two equal spans of 112.00 feet. an aashto deck overhang 3.00 ft guidelines provides a thorough background and guidance on deck design. adot bridge practice guidelines specify that deck design be based on the
6 design information meadowburke www.meadowburke.com mb0216 joist spacing double s p a c i n g safe spacing l in inches of supports for double ledger continuous overthree or more spans 1 all values based on 2005 nds for lumber species with the above properties
lrfd bridge deck design deck overhang the deck overhang design requires checking three cases lrfd a13.4, in reverse order for the presentation : design case 3: the loads specified in article 3.6.1 that occupy the overhang for the load combination strength i limit state;
01/19 1 general and technical information safety general and technical information dayton superior bridge deck forming accessories are intended only for use by trained, qualified and experienced workers.
design example 3-1 b s d i example 1: three-span continuous strht composite i girder load and resistance factor design third edition -- customary u.s. units by and michael a. grubb, p.e. robert e. schmidt, e.i.t. bridge software development international, site-blauvelt engineers cranberry township, pa pittsburgh, pa b s d i design
impact of overhang construction on girder design 5. report date november 2009; revised may 2010 6. performing organization code 7. author s seongyeong yang, todd helwig, rich klingner, michael engelhardt, and jeremiah fasl 8. performing organization report no. 0-5706 9. performing organization name and address center for transportation research
and bridge division for the design and detailing of concrete deck slabs. it will also provide design aids and other sources of information along with cross references to other parts of this manual to assist in the design and preparation of plans. references to lrfd design specifications refer to the current aashto lrfd bridge design
5 design information meadowburke www.meadowburke.com mb0216 2 6 lumber properties * rough dry sizes are 1/8" larger, both dimensions. based on a unit weight value of 40 lb. per cu. ft. actual weights vary depending on species and moisture content.
for the extreme limit state, the applied loads for deck overhang design are horizontal and vertical vehicular collision forces. these forces are checked at the inside face of the barrier, the design section for the overhang and the design section for the first bay, as described in 17.6.
design of deck reinforcement, including flexural resistance, limits of reinforcement, and control of cracking is based on aashto lrfd bridge design specifications 5.7.3 typical rectangular beam design . the following design method can be used for normal weight concrete with specified compressive strengths up to 15.0 ksi.
i'm currently designing a deck overhang with a tl-4 barrier using aashto lrfd. for design case 1 extreme event limit state , the overhang must be designed for the vehicular collision plus dead load moment acting concurrently with the axial tension from verhicular collision force.
reinforced concrete slab design using the empirical method bridgesight solutions for the aashto lrfd bridge design specifications bridgesight software tm creators of effective and reliable solutions for the worlds bridge engineers
6. overhang details are applicable for solid barriers only. other types of barriers example: see-through barriers will require a special design. 7. for steel girders, the transverse reinforcement shown for the exterior deck span should be verified for overhang demands. 8. overhang details are not designed for soundwall loading. 9. f t h
december 2004 lrfd bridge design 9-1 reinforced concrete decks on girders are the predominant type of deck used on highway bridges in minnesota. the deck is the structural element that transfers vehicle and pedestrian loads to the girders. it is analyzed as a continuous beam with the girders acting as supports. the
nhdot bridge design manual v2.0 page xv january 2015 appendix a appendix 7.2-a1 steel beam parabolic haunch equations 7.2-a1-1 appendix 7.2-a2 camber tolerances 7.2-a2-1 appendix 7.3-a1 deck design tables 7.3-a1-1 appendix 7.3-a2 bridge deck reinforcing 7.3-a2-1 appendix 7.3-a3 deck overhang design example 7.3-a3-1
steel bridge design handbook november 2012 u .s. department of transportation federal high way administration bridge deck design. archived. publication no. fhwa-if-12-052 - vol. 17
the aashto lrfd bridge design specifications second edition, 1998, including interims for 1999 through 2002 . the design example and commentary are intended to serve as a guide to aid bridge design engineers with the implementation of the aashto lrfd bridge design specifications, and is offered in both us customary units and standard
design step 4 design of deck prestressed concrete bridge design example task order dtfh61-02-t-63032 4-3 for this example, a slab thickness of 8 in., including the ½ inch integral wearing surface, is assumed. the integral wearing surface is considered in the weight calculations.
4.2 deck design this example will use the standard deck slab design as explained in the design guide. this design should always be used unless approval to use a thinner deck is obtained from the state bridge engineer. 4.2.1 standard deck slab design the nmdot standard deck slab detail and slab design tables are shown below. t in s ft
illustrated through the design example presented herein. the example illustrates the design of a typical three-span continuous strht steel i-girder bridge with spans of 140-0 175-0 140-0. specifically, the example illustrates the design of selected critical sections from an exterior girder at the
section 5 bridge decks 5.1 concrete deck slabs 5.1.1 composite design concrete deck slabs on steel girders are almost always designed to act compositely with the girders. composite design provides an advantage in reducing the necessary section of primary members and also serves to significantly stiff en the bridge.
c52 2x4 guard rail receptacle and c54 bridge overhang bracket extender the c52 guardrail receptacle is designed to allow the easy installation of an ohsa required lumber guard rail post on the exterior formwork of a bridge deck. the c52 receptacle bolts securely to either the c49 bridge overhang bracket and/or c54 extender
this example illustrates the design of a two span cast-in-place post-tensioned concrete box girder bridge. the bridge has spans of 118 feet and 130 feet. the deck overhang 2.63 ft guidelines provides a thorough background and guidance on deck design. adot bridge design guidelines specify that deck design be based on the
the first design step for a concrete bridge deck is to choose the correct design criteria. the following concrete deck design criteria are obtained from the typical superstructure cross section shown in figure 2-1 and from the referenced articles and tables in the aashto lrfd bridge design specifications through 2002 interims .