Design of lattice girder pdf files

For a particular girder span and bridge width, a large number of parameters control the design of the bridge such as girder spacing, cross sectional dimensions of girder, deck slab thickness, number of strands per tendon, number of tendons, deck slab reinforcement, configuration of tendons, anchorage system, prestress losses, concrete. Girder assemblies for the new tappan zee bridge tappan zee plate girder approach erection project participants. Girders in which the web members take the form of open lattice work are generally classed as lattice girders. These consolidated findings allow to include the pantex lattice girders into the design of the shotcrete layer according to the reinforced concrete concept.

Precast concrete lattice girder slabs consist of a precast plank typically 5065mm thick, with a lattice girder truss which protrudes from the plank to provide. However, the present design method for the elements is based on empirical expressions and is believed to be over conservative. Owner new york state thruway authority designbuild team tappan zee constructors american bridge traylor brothers granite construction fluor buckland and taylor main span hdr approaches. This design example was edited in 2012 by hdr engineering, inc. If capacity of crane is moderate, the gantry girders rest on brackets connected to roof column of industrial shed. The lattice girder was used prior to the development of larger rolled steel plates. Mar 23, 2020 a lattice girder is a type of girder with a crisscrossed web design, such as in gardening lattices, between the two edges of the girder. The loadbearing capacity of pantex lattice girders has been investigated with. Contrary to standard solidweb girders, pantex lattice girders are entirely integrated in the shotcrete lining. Pdf evaluation of the structural performance of tetragonal lattice. Arranging several pieces of timber or steel into a structural frame or truss. The goal was to put stairways in it, and also to leave some space for some type of vertical transporter.

Pdf design optimization of box type girder of an overhead crane. Analysis and design of prestressed box girder bridge by irc. Design to ec3 part 15 nanyang technological university. The design resistance of joints between the braces and chords are expressed in terms of design axial andor moment resistances of the brace members, or, in some cases, in terms of design axial resistances of the chords. Possible dimensions are stated below or can be found in the product range. 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. A lattice girder is a truss girder where the load is carried by a web of latticed metal. Design manual of welded and coldformed hollow sections, ferpinta, 2014.

Hshaped steel ribs and triangular lattice girders have been widely used as a. Red bold font failed code check disclaimer this spreadsheet was tested for reliability and accuracy by. Aashtolrfd design example horizontally curved steel box girder bridge final report prepared for national cooperative highway research program transportation research board national research council john m. Filigran offers various types of lattice girders, which are sized to order. It is a semiprecast floor system consisting of a precast panel with a minimum thickness 40 mm, a lattice girder wire trusses, and bottom reinforcement. Pdf guidelines for modelling lattice girder structures. The loads may be static, as in the case of buildings, or dynamic, as in the case of bridges. A discussion of overall truss design considers primary analysis, secondary stresses, rigorous elastic analysis, cross braced trusses and truss deflections.

Pdf evaluation of the structural performance of tetragonal. The lattice girders are used mainly as reinforcement of prefabricated slabs and beams, where concreting is performed in two stages, offering the advantage of avoiding scaffolding and formwork needed in traditional construction. Hshaped steel ribs and triangular lattice girders have been widely used. Pdf on oct 1, 2009, elizabeta hristovska and others published modelling of welded truss joints od lattice girder find, read and cite all the. This bridge is the igirder design example presented in the appendix of the aashto guide specifications for horizontally curved steel girder highway bridges, 2003. A test was conducted on two lattice girder elements in order to evaluate the mechanical behaviour in bending. Llc requires design by a registered professional structural engineer. They showed that the loadcarrying capacity of a slab depends on the rotation capacity of the lattice girder joints. May 30, 2012 this is some kind of universal lattice girder pillar, dimension 6m high and base 2mx2m made from 100x100mm and 50x50mm profiles. Evaluation of the structural performance of tetragonal lattice girders article pdf available in international journal of steel structures 1 june 2012 with 2,156 reads how we.

When the order is placed, the lattice girder height h, lower chord diameter lc, upper chord size uc and diameter of diagonals d are specified. Such lattice girders are usually deeper and much lighter than regular girders and hence are economical, particularly when repetitive fabrication is taken advantage of. Wassef christopher smith kevin johns modjeski and masters, inc. Pdf modelling of welded truss joints od lattice girder researchgate. The resulting outcome of a design is the set of execution documents for the structure. It has been supplanted in modern construction with welded or bolted plate girders, which use more material. August borsig, its design er, ran tests by spanning the. The units are typically 50mm to 100mm thick and 1200mm or 2400mm wide. View initial results incanvas or purchase detailed girder design documentation in pdf format using cloud credits. Box girder bridges bridges design for halfthrough construction. Design composite floors using lattice girder planks are designed in accordance with the relevant sections of eurocode 2.

Equations used in gantry girder design free pdf file sharing. Continental steel public seminar, 6 august 2014, ntu design of plate girder design of plate girder shear resistance if the web is stocky, no shear buckling of web shall occur and the shear strength of the web is given by ec3 part 11 if the web is not stocky, shear buckling governs the failure. The steel girder design criteria are obtained from figures 31 through 33 shown below, from the concrete deck design example, and from the referenced articles and tables in the aashto lrfd bridge design specifications through 2002 interims. Eurocode 3 distinguishes between six different failure modes for joints in lattice structures. This lecture presents the types and uses of trusses and lattice girders and indicates the members that are most often used in their construction. Structural steel 1 of 18 rev plate girder design project. Lattice girder slabs act as permanent formwork and as precast soffits for robust, high capacity composite floor slabs. Lattice girders available in straight and arched segments lattice girder bar material. Design guidelines for steel trapezoidal box girder systems. Lattice girder joints design of joints in steel and.

Characteristics design of gantry girder is a classic example of laterally unsupported beam. This paper presents an evaluation of the structural performance of tetragonal lattice girders for natm tunnel construction. They are cast with most, if not all, of the bottom reinforcement required. Aggregate up to 8 pdm microphones and connection to a processor over i2s or spi with no impact in audio quality. Double bridge girder overhead cranes are used for heavy duty applications in the industry. Figure 1 illustrates a simply supported lattice girder. A truss bridge is a bridge whose loadbearing superstructure is composed of a truss, a structure of connected elements usually forming triangular units. The terms are generally applied to the planar truss.

Pdf modelling of the lattice girder structures is a difficult and complex problem. Because of delamination issues, the design of the coreto facesheet bond in metallic honeycomb sandwich panels has received much attention 9. The excellent interlocking of pantex lattice girders with the shotcrete has been determined by several pullout tests in terms of characteristic curves. From the results in this study, it was concluded that the studied detailing of. Cbetaffagmagnetsandgirders girder correctormagnettests. The connected elements typically straight may be stressed from tension, compression, or sometimes both in response to dynamic loads. The design of truss railway bridges is beyond the scope of this publication, but. Lattice girder pillar with stairways 3d cad model library.

Agency those documents are now part of the design manual for roads and. The practical design of truss members is discussed. The recommended spandepth ratio for simply supported girder varies between 12 for short span and 20 for long span girder. It was the first german lattice truss bridge to graduate from its experimental phase to the railway network. Therefore, it is recommended that the rotation capacity is not limited by the horizontal cast joint. Design of a largespan industrial building with special. Structural performance of precast concrete lattice girder.

Pdf this paper presents an evaluation of the structural. For this steel girder design example, a plate girder will be designed for an hl93 live load. Design of prestressed concrete igirder bridge superstructure. Pantex lattice girder integrated in shotcrete as performed onsite geometry. Drawings, girder magnet and bpm bracket components. Butzows wrought iron lattice truss bridge across the nebel river. The spatial configuration of the lattices in all mechanization machines and the complex design of the. Builtup timber sections with the beam members nailed.

Therefore lattice girders are best suited when slab reinforcement is generally light, while at the same. Curved steel 3d example aashtoware bridge design and rating. Abstract the purpose of this example is to illustrate the use of the aashto lrfd bridge design for the design of a continuous two span steel i girder bridge. Design guidelines for steel trapezoidal box girder systems 6. Fabrication, construction and assembly of the girderslab system and dbeam girder shall be in conformance with the girderslab system design guide v3. Authors todd helwig, joseph yura, reagan herman, eric williamson, dawei li 8.

The design shear forces and bending moments are shown in fig. Trusses often serve the action of the girder in transferring the gravity load over larger span, and are referred to also as lattice girders. The truss or lattice girder is a triangulated framework of members where loads in the plane of the truss or girder are resisted by axial forces in the individual members. To design prestressed girders using line girder analysis. Lattice girder elements are used as permanent formwork in insitu concrete construction. However, it is entirely responsibility of the spreadsheet user to verify the applicability. The diagonal lines of steel give support in all directions, helping to prevent the girder, which is one of the main support elements in a bridge design, from bending. Pantex lattice girders ensure an immediate support in the open span area. The example illustrates the design of a typical threespan continuous straight steel igirder bridge with spans of 140. These consolidated findings allow to include the pantex lattice girders into the design of the shotcrete layer. In this paper a detailed parametric design optimization of the main girder of box type is performed for a.