The slab bottom soffit has a parabolic profile with minimum depth at midspan and maximum depth at pier. Continuous span reinforced concrete slab bridge vdot. The arch is a concrete slab that is 8 inches thick and 16 feet wide throughout the. Longitudinal steel should be detailed in a 2bar alternating pattern, with one of the bars continuous through the slab. 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. In addition to general design guidance and information on detailing practices, this section contains three design examples. These examples are modifications of the bridge approach slab base sheets.
Bridge approach slab analysis and design incorporating elastic soil support presented by. Pdf design and behavior of spread slab beam bridges. The approach slab serves as a bridge between the roadway and the primary bridge and is intended to reduce the annoying and sometimes unsafe bump that is often felt when approaching and leaving a bridge. In addition to this, during construction of the bridge, we established practices for traffic control in. For simply supported spans, this limit is generally found to be nearly 10 metres and for continuous or balanced cantilever type. The bridge is a slabongirder type with a skew angle of 20 degrees over a. Design a solid slab bridge superstructure having a clear span of 9. Tutorials on bridge design and assessment with examples. Posttensioned concrete haunched slabs standards will extend the span range capabilities of the shallowdepth slabs from 20 m 66 ft to 28 m 92 ft, in addition to providing a high performance type bridge superstructure. The design principles of a solid slab bridge deck may be illustrated by the following illustrative example. Example on design of slab bridge design data and specifications superstructure consists of 10m slab, 36m box girder and 10m tgirder all simply supported. A comparative design of reinforced concrete solid slab bridge. Slab bridge definition is a shortspan bridge consisting of a reinforcedconcrete slab resting on abutments.
Late in the 1970s, cablestayed construction raised the bar for concrete bridges. If this box is not checked, the rating will use section properties computed. Comprehensive design example for prestressed concrete psc girder superstructure bridge design step 7 design of substructure design step 7. The guidebook 2 is written in a userfriendly way employing only basic mathematical. Bridge design free download as powerpoint presentation. Uptodate coverage of bridge design and analysis revised to reflect the fifth edition of the aashto lrfd specifications design of highway bridges, third edition offers detailed coverage of engineering basics for the design of short and mediumspan bridges. Reinforced and prestressed concrete are used extensively in bridge projects. This manual is also complementary to the bridge branch design information manual.
Master of science and hereby certify that, in their opinion, it is worthy of acceptance. After reading this article you will learn about the design of slab and girder bridges. If this box is not checked, the rating will use section properties computed from the total deck thickness. The steel reinforcement in the concrete slab was improperly designed, resulting in. Slab bridges, due to camber required to address future creep deflection, do not ride ideally for the first few. Concrete deck slabs can be constructed with castinplace or precast methods, and typically include mild steel reinforcement in the longitudinal and transverse directions. Bridge slab design spreadsheet civil engineering downloads. Design step 4 design of deck prestressed concrete bridge design example task order dtfh6102t63032 43 for this example, a slab thickness of 8 in. Only the design of slab bridge will be used for illustration.
A comparative design of reinforced concrete solid slab bridge for different spans g. Single, double or triple cell boxes, of equal spans, may be analysed on fixed or spring foundation supports. Reinforced concrete slab design using the empirical method. Slab design reading assignment chapter 9 of text and, chapter of aci31802 introduction aci318 code provides two design procedures for slab systems.
This is a partially finished form diagram of a bridge that will span 99 feet. In the case of the slab, the origins are found in prehistory, as in the ancient clapper bridges of dartmoor and dartmeet, england whitney 1983. For simply supported spans, this limit is generally found to be nearly 10 metres and for continuous or balanced cantilever type structures, this limit is 20 to. Mar 01, 2012 bridge engineering handbook is a unique, comprehensive, and the stateoftheart reference work and resource book covering the major areas of bridge engineering with the theme bridge to the 21st century. This help file describes input and analysis features of slab bridge designer 2. Tech scholar, structural engineering, malla reddy engineering college autonomous, secunderabad.
Simple span reinforced concrete slab bridge rating example. Ramakrishna2, associate professor, department of civil engineering, malla reddy engineering college autonomous, secunderabad. Pdf the texas department of transportation txdot uses precast prestressed concrete slab beam bridges in a sidebyside configuration. Types and design methods of reinforced concrete bridges are presented. The minimum spacing of reinforcing bars should preferably be 6 in. A basic introduction to the design codes and methods of anlysis. Lrfd slab bridge design procedure, equations, and outline. Case study design of a concrete bridge 147 chapter 9.
Slab detail description example 1 jointless abutment with parapets, 20 degree skew ahead left. This system used load and resistance factors to ensure a stable bridge with sufficient strength. Wisdot bridge manual chapter 18 concrete slab structures january 2019 188 18. The bridge is striped for two lanes, but there is a possibility that it could be modified or restriped in the future for additional lanes. Integral abutments are used to eliminate expansion joints at the end of a bridge. Ultrahigh performance fiber reinforced concrete elements pdf. Specifically, the example illustrates the design of selected critical sections from an exterior girder at the strength, service and fatigue.
It has been written with practicing bridge and structural engineers in mind. Check this box if the structural slab thickness should be used to compute section properties for rating. Concrete slab bridges as with most modern bridge forms, the slab bridge hearkens back to precursors from the remote past. Design steps for slab and edge beam a slab design span length span length, s centre to centre distance of the supports. This spreadsheet enable you to design bridge slab bending moments, shear and axial forces for loads on a buried concrete box structure, as described in bd 3101, are calculated. A comparative design of reinforced concrete solid slab bridge for.
If the outtoout width of a slab bridge exceeds 45 ft. The original bridge and structures design manual was created through the publicprivate partnership of the georgia department of transportation and the consulting engineering companies of georgia. Comprehensive design example for prestressed concrete psc. Slab and girder bridges are used when the economical span limit of solid slab bridges is exceeded. By 1982, the sunshine skyway bridge in tampa, florida, had set a new record for concrete bridges, with a main span of 365 m 1,200 ft. Eight walls spaced 11 feet apart bring total loads of 120 kips each from the stiff deck to a concrete arch below. Plan n design free drawings, autocad, autocad drawings. E dge beam design is required for bridges with open joints and possibly at stage construction lines. The integral wearing surface is considered in the weight calculations. The selection criteria of bridge railings and the railing details included in chapter 5 of ladotd bridge design manual 4th english edition shall be followed. Design of bridge deck slabs using glass fiberreinforced polymer gfrp bars of different grades. En 199315 used for bottom flange of a boxgirder bridge different effectives width for sls and uls combinations of actions 3 options at uls choice to be performed in the national annex b eff,flange b flange. The form was subsequently abandoned at an early period. Design of reinforced concrete bridges department of civil.
Again, there is some overlap between the two, but basically the information manual is more. En 19942 same effectives width b eff for sls and uls combinations of actions steel flange. Slab bridge definition of slab bridge by merriamwebster. Bridge design manual lrfd 22 txdot 012020 chapter 2 limit states and loads section 1 limit states section 1 limit states importance factor classify all bridge designs as typical bridges when applying the operational importance factor. Revised to conform with the latest fifth edition of the american association of state highway and transportation officials aashto. Nov 23, 2015 components of slab bridge slab footing abutment slab edge beam fig reinforced cement concrete slab bridge stringer 14.
Bridge approach slab detail examples examples of approach slabs with a range of different abutment types, barrier types, and drainage inlet locations are found below. For concrete slab design, the slab dimensions and the size and spacing of reinforcement shall. Reinforced slab bridge designaashto allowable stress design. Generally, reinforced concrete deck slabs are the most often used type of deck for steel bridges.
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