Pad thickness is determined in increments of . 349.2R-5. 20 Full PDFs related to this paper. The bearing plates spanned approximately 1'-5". Since N is known, this limit state can be solved for B. and W The larger the diameter of the wedge plate, the less load is applied to the middle of the bearing plate. Several design examples are provided in the following sec-tions for each loading case. B of the base plate. Elastomeric Bearing design shall follow AASHTO LRFD “Method A”. See Figure 3. Click on image to get larger view. For such col-umns, the simple column-base-plate connection detail shown in Figure 1.1 is sufﬁcient. The bearings are normally vulcanized to a top plate or sole plate. geometrically similar to and concentric with the loaded area". 2.2 Base Plate Design for Fabrication Typically, except for very large columns with very heavy base plates, such as for high rise buildings, base plates are shop welded to the column. design example includes detailed design computations for the following bridge features: conc rete deck, steel plate girder, bolted field splice, shear connectors, bearing stiffeners, welded connections, elastomeric bearing, cantilever abutment and wingwall, hammerhead pier, and pile foundations. into the design inequality for the limit state of concrete bearing strength. 18. pressi n bearing l cati n. The auth rs present an ther base plate bearing interface cantilever directi n appr ach,usingfact redl adsdirectlyinameth dc nsis- parallel t m ment directi n, in. Stud welding of. Download Full PDF Package. Civil Engineering & Design . The design procedures and examples which fol-low the discussions are given first in … The last thing to specify is the thickness of the plate. 7-4. Plate load test is a field test which is commonly adopted to determine the bearing capacity and settlement of soil under a given condition of loading. The action is essentially the same as a footing that distributes a large load to The maximum Steel Design Guide Series Column Base Plates. The values of Ru and Ra are the LRFD and ASD factored loads, respectively, applied to the beam. 7-2. have been increased in the 2010 Specification]. Given the load and allowable bearing pressure, the area of the plate is easily computed. crippling. 37-40. - The tabulated numbers must be multiplied by the plate thickness to calculate the design bearing strength of the plate. (N1B1) = (N1(B2/B1) The thickness of the upper bearing plate can be determined as follows: M = R D + L + Φ 2 × D + 100 2 = 4433.9 × 10 3 2 × 270 2 = 299, 288, 250 N mm. The bearing plate is necessary to avoid crushing of the weaker material and to distribute the As previously discussed in section 8.6.4, the bearing plate is modeled as a The beam is supported on a 2x4 top plate. bearing type is currently being used on new bridges. One is found in section J8 and two are in section J10 of the specification. Create a free account to download. It is advisable to design the connection between such stiffeners and the flange to resist the tensile force due to the change of direction of the flange plate, ignoring the bearing reaction. These base plates are referred to as lightly loaded column base plates, and they require a modified design approach. Example A1, continued CODE SECTION DESIGN PROCEDURE CALCULATION STEP 4: Check plate thickness Since the load is applied directly over the stud, the only requirement on plate thickness is that it satisfy the minimum thickness required for stud welding. contacts the plate, distributed over a smaller area that is N wide and a Design a beam bearing plate 11. "Design of Steel Bearing Plates," Engineering Journal, American Institute of Steel Construction, Vol. long test specimen of the concrete used for the bearing the available width and bearing stiffeners are added to the beam. BASE PLATES for columns and bearing plates for beams resting on masonry are details associated with the design of all steel structures. then compare this against the available length for bearing on the supporting surface. about elastomeric bearings. Fling, Russell S.
resulting substitution for A2/A1 can then be substituted 751.11.2 Design 7184.108.40.206 Elastomeric Bearings. Misael Espinosa. (when A1 = A2), so equation J8-2 can be used at all times. Figure 220.127.116.11.1 General elastomer material properties and selection criteria (S18.104.22.168) Commonly used elastomers have a shear modulus between 0.080 and 0.175 ksi and a nominal hardness between 50 and 60 on the Shore A scale. softer soil. diameter x 12 in. Design procedures presented in the AISC Manual are silent on two important questions. This course is also perfect for engineers who are preparing for the civil / structural engineering PE exam. 3. (1970). READ PAPER. The following is an example of a note that should be shown on the plans: The attached picture is from a recent tieback anchor project. Pp Parameters Maximum laminated pad thickness is . for additional information that may affect the design of bearings. - The design bearing strengths are given for different bolt spacings (2.67db and 3db), different Fu (58 and 65 ksi), and different bolt diameters (5/8 – 1-1/2 in.) A short summary of this paper. limit states and the associated reduction factor and factor of safety are given 130 East Randolph, Suite 2000, Chicago, IL, 60601. The width of the test bearing plate should not be less than 30 cm. The first is the axially loaded ... design. Example A1, continued CODE SECTION DESIGN PROCEDURE CALCULATION STEP 4: Check plate thickness Since the load is applied directly over the stud, the only requirement on plate thickness is that it satisfy the minimum thickness required for stud welding. DES 345 –Connection Design Examples NDS CH. 7-7. The guidance covers: partial depth flexible end plates fin plates … over a larger area that is made of a material that is not as strong as steel. (up to a limit). 2- The main function of the weld is to hold the column shaft securely in position on the base plate and to … The second case, shown in Fig. B.5.2 Example: Large Moment Base Plate Design, Triangular Pressure Distribution Approach Design the base plate shown in Figure B.4 for an ASD and LRFD required strength of 60 and 90 kips, respectively, and moments from the dead and live loads equal to 480 and 720 kip-in., respectively. the distances "B" and "N" are the same as previously defined, while "C" equals Beginner's Guide to the Steel Construction Manual, 13, Transverse thickness. The function of anchor bolts is to transfer loads to the masonry from attachments such as ledgers, sills, and bearing plates. This document makes the following design and detailing assumptions for elastomeric bearings: 1. x/i. IOWA DOT ~ BRIDGES AND STRUCTURES BUREAU ~ LRFD BRIDGE DESIGN MANUAL ~ 5.7: 2. Other items affecting the bearing problem may be the presence of a nearby bolt or the proximity to an edge in the direction of the load. 1- Base plates will usually be flame cut or sawn from S275 or S355 plate. Stud welding of. 7.59). Reinforced concrete structural software includes programs for column design (pcaColumn), beam design (pcaBeam), slab design (pcaSlab), wall design (pcaWall), mat design (pcaMats), foundation design, … The steel for the bearing plates had Fy = 50 ksi. Click on hotlinks in image to get larger The statement of the Lateral support is provided only at the ends of ... face to face of supports, plus ½ the required bearing length at each end. from this, … These plates are designed to transfer the ASD demand incremental bearing loads from the floor below via bearing from the top plate below, then through the blocking and the sole plate and into the rod via either a nut or an attached ratcheting device. All Rights Reserved. The Design Examples are arranged with LRFD and ASD designs presented side by side, for consistency with the Manual. P:\Pub\Pub800\SIGN_OFF\P364\P364-Intro text.doc vi Printed 29/10/09 SUMMARY This publication presents 20 design examples to illustrate the use of Eurocodes 3 and 4 B2) B > Req'd Pp / (f'c min[0.85 N2, 2 / DESIGN GUIDE 1, 2ND EDITION / BASE PLATE AND ANCHOR ROD DESIGN The vast majority of building columns are designed for axial compression only with little or no uplift. General. This section is intended to provide general design guidance and information on detailing practices. 37-40. 6. inches at abutments and 4 inches at hinges. defined as the "maximum area of the portion of the supporting surface that is The design value for the bearing strength concentrated around the footprint of the column section under the base plate (Fig. 27.4 Design Example ..... 19 . supporting surface will not experience crushing failure. Steel Design Guide Series Column Base Plates. Bridge Design to Eurocodes Worked examples Worked examples presented at the Workshop “Bridge Design to Eurocodes”, Vienna, 4-6 October 2010 Support to the implementation, harmonization and further development of the Eurocodes Y. Bouassida, E. Bouchon, P. Crespo, P. Croce, L. Davaine, S. Denton, M. Feldmann, R. Frank, JUNE 2008 LRFD BRIDGE DESIGN 6-1 6. Next, determine the bearing-plate sizes and capacities. Misael Espinosa. use one of the equations below to find the ratio of A2/A1 The limit state for bearing on concrete is found in SCM J8. If B2 then overhangs the edge of the available concrete, then B.5.2 Example: Large Moment Base Plate Design, Triangular Pressure Distribution Approach Design the base plate shown in Figure B.4 for an ASD and LRFD required strength of 60 and 90 kips, respectively, and moments from the dead and live loads equal to 480 and 720 kip-in., respectively. 20 Full PDFs related to this paper. N2 can be determined by the distance to edge of the available design of steel bearing plates. views. curved sole plate bearings of the type detailed on standard sheets [BSB SS 1010, 4541C-4541E]. A short summary of this paper. This will cater for situations where the load path from the bearing does not spread to the stiffener as a result of extreme thermal movement and A larger N is generally desirable but is limited by the available wall thickness. The coupon code has been removed from your cart! base plates for columns and bearing plates for beams resting on masonry are details associated with the design of all steel structures. INTRODUCTION. This is the result of READ PAPER. (B1N1) sqrt(A2/A1), 1.7 f'c This paper. Download. Base plate - Nominally pinned 201 20. If the supporting surface is not large enough then N is taken as 12.2 General Design Considerations 12.2.1 Design Method The provisions of the NYSDOT LRFD Bridge Design Specification shall be used for the design of bridge bearings. without knowing the other dimension: A2/A1 = (N2B2) / Worked examples presented at the Workshop “Eurocode 7: Geotechnical Design” Dublin, 13-14 June, 2013 Support to the implementation, harmonization and further development of the Eurocodes Eurocode 7: Geotechnical Design Worked examples designer is able to predict the behaviour of simple, continuous and semi-continuous steel frames. Both shear and tension are transferred through anchor bolts to resist design forces such as uplift due to wind at the top of a column or wall or vertical gravity loads on ledgers supporting joists or trusses (see Figure 1). reaction force over a sufficient length of beam to prevent web yielding or This solution is time consuming if more than an occasional bearing plate is encountered. strength of the concrete bearing surface is a function of the plate contact area here: [2010 Column splice - Non bearing (Net tension) 195 19. This equation can be solved directly for B1 which is the dimension The Typically, N2 is easier to determine than B2 since N2 The two in section J10 are for web local yielding and web crippling of the beam. 2. Therefore, the bolt spacing and edge distance will affect the bearing strength of a The allowable stress on the concrete is taken as 0.85f'c, where Fortunately it can be easily presented in tabular or graphical form. Relating these variables to the general discussion found in section 8.6.4, 7, pp. concrete. Design a column base plate This course is intended for practicing civil/structural engineers as well as university students majoring in civil/structural engineering. bearing. is often limited by width of the concrete element in that direction. The ratio of the concrete to base plate area (A2/A1) is 4.0. In rare instances integral pier caps or substructures will be designed using steel. Bending is about the strong axis for the These are shown in Fig. and compute N2 = N1 (B2/B1). BASE PLATES for columns and bearing plates for beams resting on masonry are details associated with the design of all steel structures. 1.7 N1]), Determining the Thickness, t, of the Plate. given the load and allowable bearing pressure, the area of the plate is easily computed. Obtain required design input LRFD steel design P p = nominal bearing capacity of concrete under base plate P u = factored column load calculated from load factors in LRFD steel design r = radius of gyration R = =generic load quantity (force, shear, moment, etc.) The bearings are normally vulcanized to a top plate or sole plate. B can now be determined, Req'd Pp = (Ru/f 7-3. The value of k is computation of Pp. 3), according EN 1993-1-8, is obtained from a cantilever with the span c: 142 Victoria-Elena Roşca, Elena-Carmen Teleman, Elena Axinte and Georgeta Băetu 3 0 y jd M f c t f , (2) where t is the thickness of the base plate. galvanized sheet metal plate (sliding bearing) above the pad. In addition, design examples and various charts in this memo provide background for the . In actuality, equation J8-1 is a special case of equation J8-2 will first determine the required width, N, based on beam web yielding and web crippling "Design of Steel Bearing Plates," Engineering Journal, American Institute of Steel Construction, Vol. (B1N2), 1.7 f'c (B1N1)]. It contains design examples and complete solutions calculated using ASD and LRFD. Fixed bearings shall be designed to transfer longitudinal and transverse forces through anchor bolts, pintles, welds, steel plates, and other positive connections. NAME: Beam Bearing Plate (1) part that represents a flat structure (1) In some contexts, for example in analysis, the term plate object may be used to refer to plates. Base plate - Column with moment 207 REFERENCES 215. Minimum laminated pad thickness is one inch. This means that B2 = B1 (N2/N1). In this test a square or circular rigid plate of standard dimension (generally 300 mm2 for square or 300 mm dia for circular) is placed at foundation level and load is applied in increments. design of steel bearing plates. / (N1B1) = (B2/B1)2. EMBEDMENT DESIGN EXAMPLES. surface. 7, pp. 6-4. Consequently, the allowable The design of column-base-plate Design (ASD) and Load and Resistance Factor Design (LRFD). It will show how to design a beam bearing plate based on three limits states. Beam Bearing Plate Design Per 13th Edition dlclarkii (Structural) (OP) 28 Jun 10 10:01. Base plate - Nominally pinned 201 20. Solutions have been developed based on the 2015 and 2018 National Design Specification®(NDS®) for Wood Construction, and the 2015 Special Design Provisions for Wind and Seismic (SDPWS, as appropriate) . Example Calculation. Given the load and allowable bearing pressure, the area of the plate is easily computed. the contacted concrete being contained. value of "C" equals 2k, the equation for thickness can be written as: <<< Previous Section <<< The upper bearing plate is shown in Figure 4.209. 299, 288, 250 200 × t 1 2 = 340 1.0. 3.2.2 Lateral Distribution of Concentrated Load The bearing plate is necessary to avoid crushing of the weaker material and to distribute the reaction force over a sufficient length of beam to prevent web yielding or crippling. This paper. 6-3. 7, pp. The ratio of the concrete to base plate area (A2/A1) is 4.0. The tieback design loads were generally in the 200 to 400 kip range. Click on image to get larger view. A bearing plate takes the reaction of a steel beam and distributes that force The bearings are attached to the girder; by field welding or bolting. Laminated (steel reinforced) bearing details and steel plate and elastomer thicknesses are given on the Standard for Elastomeric Bearings for Prestressed Concrete Girders. A bearing plate is generally a rectangular plate that can described by its area will always have one edge in common with the available concrete surface. 3. To resist a beam reaction, the minimum bearing length N in the direction of the beam span for a bearing plate is determined by equations for prevention of local web yielding and web crippling. The design is based both on: The basic limit state follows the standard form. 4. The course will also show how Excel could be used to design beam bearing plates. 22.214.171.124 Policy overview [AASHTO-LRFD 14.6.2, 14.8.1] The Bridges and Structures Bureau follows a general design policy of jointless bridges with integral abutments for short and intermediate spans, within length and skew … Depending on which is easier to obtain (N2 or B2) you can Chapter 13 –split rings and shear plates Chapter 14 –timber rivets Adjustment factors 7.