Aashto bridge design example

The primary goal of the collaboration is to achieve steel bridge design and construction of the. The use of aashto lrfd bridge design specifications with. The crosssection of the bridge is type b as described by aashto table 4. Bridge design guide txdot january 2020 feedback for txdot policy on designing bridges, please refer to the txdot bridge design manual lrfd. In order to work through a design example the designer will need the aashto lrfd specifications to determine the factored load and several sections from the bridge design manual to determine resistance factors, resistances, and appropriate plan notes. Lrfd bridge design manual bdm colorado department of. Apply the lateral force, c, at the top end of post and design as a cantilever combined with axial load. This manual documents policy on bridge design in texas.

All new retaining walls shall be designed using 2002 aashto lfd 17 th edition standard specifications. Lrfd micropile design and testing for major urban bridges. Hl93 design truck design truck consists of three axles, front and two rear axles with front axle weighing 8kip 35 kn and two rear axles weighing 32kip 145 kn. Except where noted, the design provisions employ the lrfd methodology set forth by aashto. Please direct any questions on the content of this document to the bridge design section director, bridge division, texas department of transportation. References in parentheses refer to the applicable section or equation from the above specifications. Aashto lrfd bridge design specifications first edition 3 first edition 1994 in1987,thesubcommitteesubmittedain 1987, the subcommittee submitted a request to the aashto standing committee on research to undertake an assessment of the. Aashto lrfd guide specification pedestrian bridge design example 0. A design procedure is presented first with an example given afterward for a twospan bridge.

Service life design for bridges r19a product overview comprehensive guidance to select and design durable bridge systems and components that are both easier to inspect and bettersuited to their environments. Highway and transportation officials aashto lrfd bridge design specifications1 following the recommendations of the national cooperative highway research programs nchrp report 496. Aashto guide specifications for horizontally curved steel girder highway bridges with design examples for. Aashto requires at least 1 verification test, and 5% of all micropiles to.

Pdf aashto lrfd 2012 bridge design specifications 6th ed. The bridge section is committed to providing innovative solutions for the design, construction, and maintenance of idahos transportation bridges and structures. A twospan continuous composite igirder bridge has two equal spans of 165 and a 42 deck width. Using aashto lrfd bridge design specifications 4th ed. Aash to lrfd bridge design specification, 7th edition, 2014 michigan department of transportation bridge design manual, volume 5 michigan department of transportation bridge design guide. Download free bridge design and analysis spreadsheets. Design example of precast balanced cantilever bridge design using aashto lrfd bridge design specifications prepared by teddy s. The bridge section develops plans, specifications, and estimates for bridges, sign structures, retaining walls, and other transportation structures. Lrfd steel design ohio department of transportation.

The truck axle loads are moved laterally to produce the moment envelops. Standards the following design standards were utiliz ed in this example. Guide specifications for lrfd seismic bridge design, 2 nd edition, with 2012, 2014, and 2015 interim revisions. In article 3 of this document, the load defini tions and abbreviations are taken from aashto lrfd. Introduction the aashto guide specifications for lrfd seismic bridge design referred to as lrfd seismic guide spec was approved in july 2007. Design example 37 b s d i lrfd negative moment loading article 3. Aashto lrfd bridge designaashto lrfd bridge design.

The calibration process is demonstrated using the example of vertical foundation movement that is, settlement for five methods schmertmann, hough. In an effort to update the bridge group design guidelines to reflect the latest aashto lrfd specifications, updated sections are published as they become available. Only those issues requiring additional or different treatment due to the nature of pedestrian bridges and their loadings are addressed. Lrfd bridge design manual bdm the intent of the cdot bdm is to complement current american association of state highway and transportation officials aashto load and resistance factor design lrfd specifications with current interim edition and to provide interpretations applicable to the design of colorado projects. Aashtolrfd deck design for superstructure tutorial is about control of rebar spacing, stress check under service loads, calculating distribution and shrinkagetemperature reinforcement. Lrfd steel girder superstructure design example lrfd. For example, a h1544 is a 15ton truck as reported in the 1944 specifications. Design code lanes aashto aashto chbdc std lrfd 1 1.

Introduction to lrfd 18 resistance factors article 6. Nsbasbb1ol preface this document is a standard developed by the aashtonsba steel bridge collaboration. Lever rule for computation of live load distribution. Transportation officials aashto has a series of specifications for truck loadings. Guide specifications for lrfd seismic bridge design, 1 st edition. Lrfd design example for steel girder superstructure bridge us. This page introduces the bridge design manual lrfd, which provides design methodology for bridges that considers load and resistance factors based on the known variability of applied loads and material properties. Live loads for bridges for twoaxial trucks aashto designates these vehicles as h series trucks. Methods of analysis other than those included in previous specifications and the modeling. For uniformity and simplicity, this design example is based on the aashto lrfd bridge design specifications second.

Steel girder design example using 3rd edition aashto lrfd. It has 3 basic live loads for bridges called hl93 loading where h stands for highway and l stands for loading, developed in 1993. An alternate to the seismic provisions in the aashto lrfd bridge design specifications 2011. Aashtoware bridge design and rating products training. Comprehensive design example for prestressed concrete psc. Bridge design specifications with culverts josh beakley november, 2010. The lrfd bridge design manual contains mndot bridge office procedures for the design, evaluation and rehabilitation of bridges. Nhi course 081 load resistance factor design lrfd for highway bridge superstructures, design examples pdf, 7. Incorporation of foundation movements in aashto lrfd bridge design process second edition. Design step 2 example bridge prestressed concrete bridge design example haunch depth 4 in. The procedure will explain determination of moments and capacities for one positive moment region and one negative moment region of the bridge. View example in pdf format design example 1 download example as a mathcad workbook zip castinplace flat slab bridge design.

Pci has developed preliminary design charts in accordance with the aashto. View example in pdf format design example 2 download example as a mathcad workbook zip adhesive anchor examples. The steel girders have fy 50 ksi and all concrete has a 28day compressive strength of fc 4. Approximate elastic method, or equivalent strip method aashto 4. The aashto lrfd bridge design specifications are intended for use in the design, evaluation, and rehabilitation of bridges. Consideration of foundation movements in aashto bridge design. In this document the us has been subdivided into four seismic design categories a, b, c, and d. It is assumed that those using this example are familiar with general bridge design procedures and the aashto lrfd bridge design specifications, hereinafter referred to as lrfd specifications. This bridge design excel sheet contains 11 individual excel sheets which are supported with the most recent codes like aci, aashto lrfd, and so on. The design of newly constructed bridge railings must conform to the requirements of section of the aashto lrfd bridge design specifications. The distribution factor is the reaction, r, about the hinge.

In the meantime, older sections of the guidelines remain available and are denoted with an asterisk. The charts can be accessed in preliminary lrfd design charts which you can download below. Prestressed concrete psc girder superstructure bridge design example us units pdf version 1. Aashto lrfd bridge design specifications, fifth edition with 2011 interim revisions.

Aashto lrfd bridge design specifications provisions for. Structures design office lrfd design examples files pdfs. The design provisions of these specifications employ the load and resistance factor design lrfd methodology. Details of application and calculation of design vehicular live load is explained in aashto bridge design specifications cl 3. It assists texas bridge designers in applying provisions documented in the aashto lrfd bridge design specifications, 2017, 8th edition, which designers should adhere to unless directed otherwise by this document. The truck axle loads on the deck are transmitted to girders in the transverse direction. Aashto lrfd 2012 bridge design specifications 6th ed us. Fhwa requires all bridges carrying traffic on the national highway system nhs to be.

Design example 6 appendix a example 6 deck design, inlcuding collision on a type 7 or type 10 m barrier example 6. This specification gives geometric and strength requirements and also describes crash test levels. For modifications to existing structures, states would have the option of using lrfd specifications or the specifications which were used for the original design. Example analysis using data from the portland cement association engineering bulletin 232, aashto lrfd design of castinplace concrete bridges this example demonstrates how slab bridge designer 2. If only one lane is loaded the first axle is placed 2 feet from the face of the curb. Incorporation of foundation movements in aashto lrfd. Comprehensive design example for prestressed concrete psc girder superstructure bridge with commentary.

Pdf design example precast balanced cantilever bridge. Trucks that pull trailers are designated as hs, for. Lrfd micropile design and testing for major urban bridges 1 presented by. Theryo, pe major bridge service center prepared for american segmental bridge institute note. Aashto lrfd bridge design specifications 8th edition. This design guide focuses on the lrfd design of steel beams made composite with the deck. It is commonly called as hs20 44 where h stands for highway, s for semitrailer, 20 ton weight of the tractor 1st two axles and was proposed in 1994 2. The factors have been developed from the theory of reliability based on current statistical knowledge of loads and structural performance. The specifications employ the load and resistance factor design lrfd methodology, using factors developed from current statistical knowledge of loads and structural performance. Aashto lrfd deck design for superstructure tutorial is about control of rebar spacing, stress check under service loads, calculating distribution and shrinkagetemperature reinforcement. Bridge practice guidelines lfd 2001 bridge hydraulics guidelines. The manual files are not currently available in an ada accessible format.