Designers knew that as they increased the pier size, the box girder prestressing requirements would increase. From arches to swing leaves, from foundation to superstructure, concrete is clearly a superior bridgebuilding material. Case 1 is just beside the support, case 2 is at midspan and case 3 is an artificial case with too. The ministry of shipping and transport roads wing, govt. This document is available to the public through the national technical. Seshu adluri plate girders recall compression field action in reinforced concrete beams compression struts develop because of the presence of stirrups plate girder tension field action develops because of the placement of vertical and horizontal stiffeners. It is assumed the bridge will be cast on falsework. For a type vi aashopci ibeam with an elastic modulus of 4 x 106 psi at release of strands, the creep for. Prestressed concrete decks are commonly used for bridges with spans between 25m and 450m and provide economic, durable and aesthetic solutions in most situations where bridges are needed. The bridge in this project is a twospan continuous prestressed concrete box girder bridge with ushaped precast segments pc composite u girder bridge under construction across a valley in tokushima, japan. Design and analysis of a prestressed concrete box girder. Attached is a model file and a pdf which outlines the procedure for modeling a concrete boxgirder bridge, a steelgirder bridge, and a cablestayed bridge. China electric power press continuous prestressed concrete box girder bridge design case study.
Each stands as a solid testament to concretes versatility, its cost effectiveness, and its durability. We wanted an interior structural steel girder to be placed within the plane of the precast slab units, thereby producing a thin floor construction akin to flatplate with a minimum floor to ceiling height. The tendon profile considered for the design of post tensioned box girder bridge is parabolic and mathematical model is shown in figure 6. This bridge type was selected from among others for simplified onsite construction and optimum cost reduction. Long span prestressed concrete bridges of segmental construction 16. The proposed design in volves provision of posttensioned.
Examples of bridges of this type built by the states of tennessee and. Elremaily construction technology laboratories, inc. A box girder bridge also known as a box section bridge is a bridge in which the main beams comprise girders in the shape of a hollow box. These were classified into two main types according to their method of construction, namely those constructed on falsework and those erected in cantilever. Girder analysis and design is performed using the computer. Threespan continuous straight composite i girder load and resistance factor design third edition customary u. Reinforced concrete bridges concrete reinforcing steel.
The design and optimization of segmentally precast. Plan, elevation and section views are shown on the following pages. Once the concrete has hardened, the tendons are tensioned by hydraulic jacks that react against the concrete member itself. New fhwa posttensioned box girder design manual by reggie holt, federal highway administration, and john corven, corven engineering figure 2. In these cases, straight steel box girders are used in regions where the clear span requirements preclude the use of the concrete ubeams.
Analysis and design of prestressed box girder bridge by. Analysis and design of prestressed box girder bridge by irc. Twospan castinplace posttensioned concrete box girder bridge. Elastic analysis and beam theory may be used in the design of precast segmental box girder structures. Posttensioned concrete ugirder design page 22 required for dead weight resistance until girders are made continuous use 0. The box is typically rectangular or trapezoidal in crosssection. Web design of box girders concrete bridges sciencedirect. Such was the case with the box girder as it evolved from the principle of the initial bridge beam but with the centre hollowed out. Vgc, vdc, wps, wosd and wosg are the volume of the precast girder concrete and deck slab con. The superstructure design includes the following elements. Deck design follows the nmdot standard deck slab detail in chapter 4 of the nmdot bridge procedures and design guide, hereinafter referred to as design guide.
Bridges with composite steelconcrete box girder deck have been adopted in numerous cases. This type of solution has the benefit of having great resistance relatively to its own weight, resulting from the optimization of steel and concrete properties. For this development to continue, it will be important for engineers. Such a method should only be used for special structures. Lrfd design example for steel girder superstructure bridge. Publication of this paper sponsored by committee on concrete bridges.
Freyermuth design research section portland cement association skokie, illinois continuous highway bridges with precast, prestressed girders have been built by a number of states. Upgf, updf, upanc, upsh are the unit prices of girder formwork, deck formwork, anchorage set and metal sheath for duct respectively. Concrete remains the most common material for bridge construction around the world, and prestressed concrete is frequently the material of choice. The box girder normally comprises either prestressed concrete, structural steel, or a composite of steel and reinforced concrete.
German highway administration authorities have even given external prestressing the status of the preferred solution for new concrete box girders 1. Posttensioned box girder design manual now available. Design of concrete structures shall be based on the requirements and guidance cited. Design procedures are developed for both types of construction. Chiaki nagao 1 yasushi kamihigashi2 akio kasuga 3 kenichi nakatsumi4 abstract the gunkaigawa bridge is a.
Design step 5 design of superstructure prestressed concrete bridge design example task order dtfh6102t63032 547 design step 5. Posttensioned box girder bridge an analysis approach. Overview of reinforced concrete box girder bridge design capability. Heins september, 1937 december 24, 1982 during the past decade, there has been extensive use of steel box girders for straight and curved highway and transit. The behavior of box girder section for a general case of an. By using standard sections that fabricators can purchase forms for, they are becoming a viable alternative to castinplace concrete and steel box girders for standard delivery designbidbuild projects. The refined method of analysis consist of modeling the bridge deck and girder system with finite elements.
A new precast, prestressed box girder bridge design suitable to. Customary aashtopciasbi segmental box girder standards for spanbyspan and balanced cantilever construction december, 1997, metric units including the following. Prestressed concrete continuous box girder bridge design. There is a nominal strength that is reduced by a factor which must exceed the factored design stress. Study of bridges with composite steelconcrete box girder.
Aesthetics may also become a factor when the local communities get a chance to weigh in on the material choice. Concrete structures a beginners guide to simple plate girder design to ec3 part 15. Design of prestressed concrete igirder bridge superstructure. Steel box girders and steel and concrete composite box girders are used for long spans, where the self weight of the bridge needs to be minimized, and for situations where their excellent high torsional stiffness is of particular benefit. Tentative design and construction specifications for. This example illustrates the design of a two span castinplace post tensioned concrete box girder bridge. If capacity of crane is moderate, the gantry girders rest on brackets connected to roof column of industrial shed. Examples of bridges of this type built by the states of tennessee and california are presented. Various studies have been performed so as to develop a more stable structure design by. The box girder and the truss bridge evolved together but at different paces depending on the technology available and the geographical location e. The centerline of the bridge lies on a 400 ft radius and the crosssection is a two cell box. Comparison of the amount of reinforcement for a boxgirder. In this thesis analysis and design of prestressed concrete bridges deck slab, t girder and box girder are carried out using irc.
Used in cip posttensioned concrete box girder construction, deep bridge. Analysis and design of prestressed concrete box girder bridge. This document consists of a comprehensive steel girder bridge design example, with instructional commentary based on the aashto lrfd bridge design specifications second edition, 1998, including interims for 1999 through 2002. Pdf bo x girder bridges are being made into use at many places. Concrete structures chapter 5 wsdot bridge design manual m 2350. Concrete boxgirder bridge design per aashto lrfd 2007. Tentative design and construction specifications for precast. Design of continuous highway bridges with precast, prestressed concrete girders clifford l. Transverse design of adjacent precast prestressed concrete box. Design of prestressed concrete girder bridge request pdf.
The test structure was a multispan simply sup ported bridge, with, a, castinplaceconcrete slab supported by five prestressed, precast boxbeams laterally spaced at 9 feet 6 inches. The design is based on requiring the deck to act as a rigid assembly of. To avoid this circular dilemma, only the end spansat 157 feet long, the longest in the new bridgewere posttensioned. In this thesis analysis and design of prestressed concrete bridges deck slab, t girder and box girder are. Developed by corven engineering for the federal highway administration. The behavior of box girder section for a general case of an eccentric load has been s tudied and presented its studies in chapter 2. Design to ec3 part 15 nanyang technological university.
The document also includes instructional commentary based on the aashtolrfd. A set of tendons are fished through the duct and the concrete is poured. Reinforced concrete slab design using the empirical method. Guidelines for computer modeling of posttensioned box girders. Highway bridges with precast, prestressed concrete girders clifford l. An image of a model taken from the sap2000 bridge examples document is shown in figure 1. Characteristics design of gantry girder is a classic example of laterally unsupported beam. The girderslab system and the open web dbeam girder technology are the result of more than fifteen years of research and development. Box girder types bridge building bridges of dublin. Design of a reinforcedconcrete deckgirder highway bridge. The moments obtained from this analysis are multiplied by a factor 1em to allow for the effect of creep.
When tension flanges of longitudinal girders are connected together, the resulting structure is called a box girder bridge. The factor 0 is the ratio of creep to elastic strain e creepe elastic. Appendix c prestressed concrete bridge design example task order dtfh6102t63032 c1 appendix c calculations of creep and shrinkage effects see design step 5. Abatract the economic advantages of precasting can be combined with the structural efficiency of prestressed concrete box girders for long span bridge structures when erected by segmental construction. Class 5000 or higher used in cip posttensioned concrete box girder construction, deep bridge foundations, or in other special structural applications if significant economy can be gained or structural requirements. Transverse design of adjacent precast prestressed concrete. This is a time consuming process and difficult to validate. The torsional properties of the closed section are often advantageous in reducing and simplifying the support arrangements and are.
Design and fabrication of prestressed concrete box girder. The substructure consists of integral end abutments and a multicolumn intermediate bent. A box girder of a viaduct over the ayrton sena highway, in s. Pdf explicit equations are derived for the the most economic level of prestress, within the full range of partial prestress allowed.
Pdf analysis and design of prestressed concrete box. Cantilever concrete tbeam girder bridges composed of precast reinforced and prestressed concrete beams with a t cross section and a castinplace top slab are frequently used for medium spans. Mar 27, 2019 attached is a model file and a pdf which outlines the procedure for modeling a concrete boxgirder bridge, a steelgirder bridge, and a cablestayed bridge. Design guidelines for steel trapezoidal box girder systems. Final design chapters 7, 8, and 9 of the posttensioned box girder design manual focus on final design. Design of plate girder comparing bs5950 with ec3 part 15 in plate girder design design of plate girder bs5950 most design rules found in sections 4. Concrete boxgirder bridge model tutorials computers and. By using standard sections that fabricators can purchase forms for, they are becoming a viable alternative to castinplace concrete and steel box girders for standard delivery design bidbuild projects. Comprehensive design example for prestressed concrete. This horizontally curved steel box girder br idge design example was originally developed in the nchrp 1238 project using the 1993 aashto gu ide specifications for horizontally curved steel girder bridges. Used in cip posttensioned concrete box girder construction, deep bridge foundations, or in other special structural applications if significant economy can be gained or structural requirements dictate. These include standard concrete cover and bar spacing dimensions, plus a variety of specific design and detailing instructions. The design combines the performance require ments for a japanese bridge with the simplicity of american construction practices.
Posttensioned box girder bridge an analysis approach using. Nsba white paper advantages of steel over concrete for bridge design and construction first cost, lifecycle costs, and environmental effects favor steel as the material of choice for bridges. Design step 5 design of superstructure prestressed. Key words steel, box girders, trapezoidal, torsional 18. Design of a skew, reinforced concrete box girder bridge model raymonde. The superstructure consists of two simple spans made continuous for live loads. Heins september, 1937 december 24, 1982 during the past decade, there has been extensive use of steel box girders for straight and curved highway and transit structures. Appendix b example problems transportation research board. Bridge design, steel girder, load and resistance factor this report is available to the public from the design, lrfd, concrete deck, bolted field splice, national technical information service in hammerhead pier, cantilever abutment, wingwall, pile springfield, virginia 22161 and from the. Design guide for composite box girder bridges composite box girder construction offers an attractive and economic form of construction for medium span highway bridges. Overview of reinforcedconcrete boxgirder bridgedesign capability.
Chiaki nagao 1 yasushi kamihigashi2 akio kasuga 3 kenichi nakatsumi4 abstract the gunkaigawa bridge is a sevenspan continuous rigid frame box girder bridge made of prestressed reinforced concrete, which will be 740 m long and located. This document consists of a comprehensive design example of a prestressed concrete girder bridge. The external prestressing of box girder bridges has received increasing attention in recent years, both for new bridges and for the retrofitting of existing bridges 1, 2. Pdf the design of posttensioned concrete boxgirders to.
The bridge decks have three number tbeams of varying depths depending upon spans. New codes for the design of concrete structures in the netherlands give designers the opportunity to utilize the possibilities of partial prestressed concrete. Longitudinal superstructure analysis and design are addressed in chapter 7. Box girder bridges from steel box girders and steel and concrete composite box girders are used for long spans, where the self weight of the bridge needs to be minimized, and for situations where their excellent high torsional stiffness is of particular benefit. The concrete reinforcing steel institute is proud to honor five great concrete bridges built between 1990 and 2000. Deck slabs without transverse posttensioning shall be designed under the applicable provisions of section 5 concrete design. Guidelines for design and construction of decked precast, prestressed concrete girder bridges final report prepared for national cooperative highway research program transportation research board national research council r. Concrete bridge technology design considerations for. The example problem is a three span continuous box girder bridge that is 700 ft.
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