When welded with , , or alloy filler regardless of thickness, and when welded with , , or alloy filler for thicknesses 0. When welded with , , or alloy filler. When welded with , , or alloy filler regardless of thickness, and when welded with , , or alloy filler for thicknesses 9. Table A.
At other locations, the strengths in 1 apply. The effect of eccentricities at connections shall be addressed as required Section properties such as cross-sectional area, moment by Section J. Cross section dimensions shall not vary by more Design using the provisions for Load and Resistance than the tolerances given in Aluminum Standards and Data. All provisions B.
Building-type structures shall be designed for the nominal Design shall satisfy Equation B. In the absence of a building code Ru fRn B. All provisions of this Signs, Luminaires, and Traffic Signals. Other structures shall Specification except Section B. Design shall satisfy Equation B. No applicable strength or serviceability limit state shall be exceeded by the loads and load combinations given in B.
Stability of the structure and its components shall be B. The required strength of structural members and con- B.
Structures and their components shall meet the service- Computation of forces, moments, and deflections shall be ability requirements given in Chapter L. Fatigue ments of Appendix 6. Postbuckling constants k1 and of Appendix 4. Table B. Notes 1. Ct shall be determined using a plot of curves of limit state stress based on elastic and inelastic buckling or by trial and error solution. For all flat elements, if the inside corner radius exceeds 4 times the element thickness, the inside radius shall be B.
Dimensions and properties of stiffeners shall be deter- B. For flat elements: B. Figure B. Use buckling constants for unwelded metal Table B. For uniform compression on elements with linearly vary- ing thickness with d 2. Io is the moment of inertia of the portion shown in the partial section. Use buckling constants B. Use buckling constants for. For a buckling 3. Analysis shall be conducted for either: member and connection deformations that contribute to displacements of the structure; a The LRFD load combinations with the results used 2 Second-order effects including P-D effects the effect of directly to obtain the required strengths, or loads acting on the displaced location of joints or nodes in b 1.
The effect of geometric imper- C. The effective length factor k placements shall be placed to cause the greatest destabiliz- of all members shall be taken as 1. Bracing intended to define the unbraced length of mem- 4 Member stiffness reduction due to inelasticity. The effect bers shall have sufficient stiffness and strength to control of member stiffness reduction due to inelasticity on the member movement at the brace points. Weld metal in plug or slot welds shall not be included a For tensile yielding in the gross section: in the net area.
Buckling constants are given in Tables B. For weld-affected members see Section E. As an alternate to Section E. The nominal member buckling strength Pn of members with longitudinal welds is E. Use buckling If the local buckling strength is determined from Sec- constants for weld-affected zones Table B. For open shapes not subject 0. For single angles, Buckling constants are given in Tables B. For weld-affected members see Section F. Section F. For other members, Cb shall be taken as 1 or deter- buckling stress Fb is: mined in accordance with Section F.
State Fb rye Cb Limits F. Concentrated load applied at the centroid at the free end 1. For simply sup- ported singly symmetric shapes with 0. For singly symmetric I shapes, as an alternative to Equation F. For other closed Figure F. For other closed shapes subject to lateral- torsional buckling, the nominal flexural strength shall not exceed the value determined in Section F.
If the leg tip is in compression, Mn is the lesser of: 1 local buckling strength determined by Section F. If the leg tip is in tension, Mn is the lesser of: c For the limit state of lateral-torsional buckling: 1 yield strength determined by Section F. Bending about principal axes is shown in Figure F. For combined axial compression and bending, resolve moments about principal axes and use Section F. Figure F. See the commentary for members is the least of the strengths for tensile yielding values for common angle sizes and equations for deter- mining bw.
If the long leg is in compression anywhere and tensile rupture or for compression yielding and local along the unbraced length of the angle, bw is negative.
For elements in compression, the flexural compressive For the limit state of yielding, the nominal flexural strength stress corresponding to the nominal flexural strength Fb is Mn is the lesser of 1.
The flange group consists of the flat elements in uniform compression and the F. The web group consists of the flat elements in flexure and their intermediate The flexural compressive stress Fc corresponding to the stiffeners. The strength of stiffened elements shall not determined using Section F. Use buck- ported at both ends with no transverse weld farther than ling constants for unwelded metal Table B. Use buckling 0. Use buckling constants for not less than the following: unwelded metal Table B.
Use buckling constants for weld- affected zones Table B. For a stiffener composed of a member on Limit State Fs lt Limits only one side of the web, the moment of inertia of 1. For a stiffener com- inelastic 1. For a stiffener com- buckling 1. The design strength and the allowable strength of con- nections shall be determined in accordance with the provi- J.
The size loaded members do not intersect at one point, the connection Sw of a partial joint penetration groove weld is the depth and members shall be designed for the effects of eccentricity. Fasteners shall not be considered to share load in com- b Length: The effective weld length Lwe for tension and bination with welds. The effec- J. In outside components of compression members:.
If only one line of fasteners is used, the components strength shall satisfy the requirements of Section B. Welded tensile weld backgouged to sound metal before welding the ultimate strengths of base metals shall be taken second side. Table J. Welded shear shear ultimate strength and the fillet size Sw at ultimate strengths of base metals shall be taken from Table A.
Slot lengths shall not exceed 10 times the slotted materials thickness. Figure J. If the effective length of a fillet weld is less than 4 times its nominal size Sw see The nominal shear strength Rn of a plug or slot weld is: Figure J.
The minimum length of segments of an intermittent fillet where weld shall be 1 in. Welded shear ultimate strengths of base metals shall be J. The nominal shear strength Table J. For lighting poles through 0. The base metal thickness for capacitor discharge stud welding shall not be J. When bolts will be aged to the T5 temper after welding, design and allowable exposed to contact with liquid water or humidity near.
Nuts for in. M6 bolts or Table A. Flat washers shall be Alclad T4. Bolt hardness shall be less than Rockwell C A bolts shall not be used. The nominal width of slots for bolts shall not be more than in. If the nominal length of the slot exceeds 2. See Section J. Slip-critical connections shall ability limit state be designed for the limit states of shear rupture in accordance with Section J.
Determine slip coef- ficients for other surfaces in accordance with the The design shear strength fRn and the allowable shear RCSC specification Appendix A. At a long slotted hole in an outer ply, a galvanized steel plate J. The plate washer or bar shall completely cover state of slip as follows: the slot but need not be hardened. Where the outer face of the bolted parts has a slope greater than with respect to a a connections with standard holes or slots transverse to plane normal to the bolt axis, a beveled washer shall be used.
The bear- J. The shear strength of hollow-end rivets with solid cross sections for a portion of the length shall be taken equal to J. This section applies to tapping screws with a nominal J. Screws shall be thread-forming or thread- Aluminum rivets shall not be used to carry tensile loads. Screws shall be installed in accordance with the manu- J. If other coatings are used, their thick- The distance from the center of a screw to an edge of a ness shall be sufficient to provide corrosion protec- tion for the intended service.
Screws in holes or screw slots and subjected to tension The nominal diameter of threaded holes for screws shall shall be designed for the limit states of pull-out, pull-over, and not exceed that given in Tables J. The nominal strength Rn for the limit state of pull-out shall Table J. Drill sile rupture shall be determined in accordance with Size in. Washers shall have a 0. The nominal strength Rn for the limit state of pull-out of a screw in a screw slot with the dimensions shown in Figure J.
Dss in. The washer may The nominal strength Rn for the limit state of screw be integral with the screw head. Size 8 0. Such stiffeners shall form a tight and uniform bearing part, which shall not be less than 1. For sinusoidal corrugated sheet, the minimum sidelap width for roofing shall equal the pitch of the corrugations, J. The minimum size of fasteners used in end laps and side For trapezoidal sheet with a depth greater than 1 in.
The maximum spacing for sidelap fasteners ing shall have a developed width equal to the width of the shall be 12 in.
Endlap fasteners shall be no more narrowest flat plus 2 in. Trapezoidal sheet with a than 2 in. Bending If camber is required, its magnitude, direction, and loca- deflections shall be calculated using the compressive mod- tion shall be shown on the structural drawings. For shapes with elements addressed by Sections B.
Wind-induced motion caused by service load combina- The effective width be of such elements in compression is: tions shall not impair serviceability. All chips and foreign matter between contacting surfaces shall M. Punched or scribed layout marks shall not remain on fabricated material designed for fatigue. The coefficient of thermal expansion used shall be per Section A.
Edges which have to dissimilar materials as described in Section M. Oxygen cutting is prohibited. Re-entrant corners shall be filleted. To hot form such alloys, they shall be 1 rapidly heated M. Holes shall be punched or drilled. Holes shall be free Where very corrosive conditions are expected, additional from excessive burrs or ragged edges. Punching shall not protection can be obtained by applying a sealant that excludes be used for castings or if the metal thickness is greater than moisture from the joint during service.
Aluminized or galva- the diameter of the hole. The amount by which the diameter nized steel in contact with aluminum need not be painted. Poor matching holes shall be rejected. Holes fiberboard, or other porous material that absorbs water shall. The nominal included angle at the apex of the cone in contact with a heavy metal such as copper. The heavy shall be Rivet heads shall be M. A fabricated member shall not vary from straight or from its intended curvature by more than its length divided by The drill M.
Welding shall comply with the AWS D1. Filler alloys shall be selected M. The contract documents shall specify if visual inspec- Tolerances on erected dimensions shall be suitable for tion is required to be performed by AWS certified welding the intended service and consistent with the geometric inspectors.
When inspection other than visual inspection imperfections used in the stability analysis conducted in is required, the contract documents shall state the method, accordance with Chapter C.
Fillers in parentheses are acceptable alternates. To weld C Tests shall be 6 5. Specific provisions for roofing and siding are given 10 3. During testing, deflections shall be 1. If the tensile yield strength of the aluminum 1. Adjustments shall also be made for differences between 1. Design strengths shall be determined using the resistance factors given in Chapter F for bending and Chapter J applied 1.
The bending strength of roofing and siding shall be Allowable strengths shall be determined using the safety established from tests when any of the following condi- factors given in Chapter F for bending and Chapter J applied tions apply. The allowable stress range Srd shall not be less than the value from Equation 3. Fatigue design of castings shall be made by testing in accordance with Appendix 1. The maximum and minimum stresses used to calculate Sre Srd 3. Flexural stress in base metal at the toe of welds on girder webs or flanges adjacent to welded C 6, 21 transverse stiffeners.
Base metal at the end of partial-length welded cover plates with square or tapered ends, with E 5 or without welds across the ends. Fillet Welds Base metal at intermittent fillet welds E Base metal at the junction of axially loaded members with fillet-welded end connections.
E 15, 17 Welds shall be disposed about the axis of the members so as to balance weld stresses. Shear stress in weld metal of continuous or intermittent longitudinal or transverse fillet welds F 5, 15, 18 Groove Base metal and weld metal at full-penetration groove welded splices of parts of similar cross B 9, 10 Welds section ground flush, with grinding in the direction of applied stress and with weld sound- ness established by radiographic or ultrasonic inspection.
Base metal and weld metal at full-penetration groove welded splices at transitions in width B 11, 12 or thickness, with welds ground to slopes 1: 2. Base metal and weld metal at full-penetration groove welded splices with or without transi- C 9, 10, 11, 12 tions with slopes 1: 2. Base metal and weld metal at full-penetration groove welds with permanent backing.
Fillet welds shall be sufficient to develop the static bending strength of the tube and be placed in the follow- ing order: weld the top of the base and the tube, then weld the end of the tube and the bot- tom of the base. The base shall be for a top mounted luminaire or as a support for a short arm, defined as that producing no more than 5 ksi 35 MPa tensile dead load stress in the tube at top of the base.
Notes: 1. See Figure 3. These examples are provided as guidelines and are not intended to exclude other similar details. Tensile stresses are considered to be positive and compressive stresses are considered to be negative.
Constant Amplitude Fatigue Cf Limit. B 4. C 3. D 3. E 3. F 3. F1 It includes criteria individual beams in buildings where the surround- for determining heat input, thermal expansion, and reduc- ing or supporting structure is capable of resisting tion in mechanical properties of aluminum at elevated substantial thermal expansion throughout the range temperatures.
The analysis methods in Section 4. The qualification testing methods in Section ments specified for the building occupancy. These heating conditions shall or flames under conditions of use and enables them relate to the fuel commodities and compartment character- to continue to perform a stipulated function.
The fuel load density flashover: the transition to a state of total surface based on the occupancy of the space shall be considered involvement in a fire of combustible materials when determining the total fuel load. Heating conditions within an enclosure. The variation of the heat- heat release rate: the rate at which thermal energy is ing conditions with time shall be determined for the duration generated by a burning material. The deterioration in strength and stiffness of structural members shall be accounted for in the structural analysis.
Yield strengths cient to cause flashover, a localized fire exposure shall be Ftym and ultimate strengths Ftum at elevated temperatures assumed. In such cases, the fuel composition, arrangement shall be determined from test data or Table 4.
Thermal expansion for temperatures between 70F and F 20C and C shall be determined using a 4. Where the heat release rate from the fire is sufficient to cause flashover, a post-flashover compartment fire shall be 4. The determination of the temperature versus time profile resulting from the fire shall include fuel load, venti- The specific heat of aluminum alloys is 0. The structural system shall be designed to sustain from the interior fire through the opening.
The shape and local damage with the structural system as a whole remain- length of the flame projection and distance between the ing stable. The method in Section forces from the region exposed to fire to the final point of 4. The foundation shall be designed to resist the fire characteristics. Interpolate for temperatures between those given in the table. Conformance of the structural system to these require- Boundary conditions and connection fixity in the analysis ments shall be demonstrated by constructing a mathemati- shall be representative of the proposed structural design.
Individual members shall be provided with adequate strength to resist the shears, axial forces, and moments 4. Connections shall develop the strength of the connected The methods of analysis in this section apply to evalu- members or the forces indicated above. Where the means ating the performance of individual members at elevated of providing the fire resistance requires the consideration temperatures during exposure to fire.
The design-basis fire exposure shall be that deter- determined using the provisions of Chapter D with alumi- mined in Section 4. The analysis shall include both a num properties as given in Section 4. The thermal response shall produce a temperature field in each structural element as a result of the design-basis fire 2 Compression members and shall incorporate temperature-dependent thermal prop- It is permitted to model the thermal response of a com- erties of the structural elements and fire-resistive materials pression member using a one-dimensional heat trans- in accordance with Section 4.
The mechan- be determined using the provisions of Chapter E with ical response shall explicitly account for the deteriora- aluminum properties as given in Section 4. Heat input shall be determined from the design-basis fire defined in Section 4.
Structural members and components in aluminum struc- The design strength of a flexural member shall be tures shall be qualified for the rating period in conformance determined using the provisions of Chapter F with alu- with ASTM E The nominal strength Rn shall by thermal expansion throughout the range of anticipated be determined using the material properties given in elevated temperatures. Load effects in the structure shall be detemined by ture are identified from records, specimens shall be cut structural analysis.
The strength of members and connections from the structure and both: shall be determined using the Specification for Aluminum Structures. Test loads shall not exceed a factored load of 1. The structure shall be visually 5. Deformations shall be recorded at each load incre- Where structural performance depends on existing welds: ment and one hour and 24 hours after the removal of the load.
The evaluation shall be documented by a written report b If welds do not meet the visual inspection criteria of that includes: AWS D1. In Equation , Lb need not be taken less than the maximum unbraced length The brace strength force or moment and stiffness kL permitted for the column based on the required force per unit displacement or moment per unit rotation axial strength Pr. The determi- load combinations.
Lateral stability of beams shall The required stiffness is be provided by lateral bracing, torsional bracing, or a com- bination of the two.
Inflection points shall not be considered. In Equation , Lb need not be taken less than the maximum unbraced length Lateral braces shall be attached at or near the compres- permitted for the beam based on the required flex- sion flange, except: ural strength Mr. In Equation , Lb need not be taken The required stiffness is less than the maximum unbraced length permit- ted for the beam based on the required flexural.
Alternatively, the stiff- b When nodal lateral bracing is used, the required strength ener may end a distance of 4tw from any beam flange that is is the sum of the values determined using Equations not directly attached to the torsional brace. In Equa- 6. Chapter K reserved. Chapter M Fabrication and Erection. The notch strength is the ultimate tensile strength of a This Specification provides the nominal strength of alu- standard notched specimen.
Kaufman documented minum structures, members, and connections. The nominal the notch strength of a number of aluminum alloy-tempers strength is usually defined as a force or moment, but in and suggested ASTM tests for determining notch strength.
Alloy-tempers with notch-strength-to-yield-strength This Specification provides two methods of design: ratios less than 1 are considered to be notch sensitive, since they will rupture at a notch before yielding. Such alloy- 1 Load and Resistance Factor Design LRFD : The nomi- tempers require a reduction in the tensile ultimate strength nal strength multiplied by a resistance factor must equal used for design.
This reduction is made by dividing the ten- or exceed the required strength determined by analy- sile ultimate strength by the tension coefficient kt, a coeffi- sis for the appropriate LRFD load combinations. This cient greater than or equal to 1. Specification provides resistance factors for building- The kt factor of 1. This Specification pro- T6. Specified strengths are A. In most instances the distri- sion than those given in this Section are given in the Alumi- bution is normal and strengths are based on the results of num Design Manual Part IV Tables 7 and 8, respectively, and at least tests from at least 10 different lots of material.
Material should not be accepted or rejected based F. These strengths are derived strengths Kaufman provide typical mechanical properties for established by multiplying strengths from tests of repre- many aluminum products at elevated temperatures. The sentative lots of material by the ratio of the specified ten- reduction in strength varies with alloy, temper, temperature, sile yield or ultimate strength to the tensile yield or ulti- and time of exposure.
Where insufficient data are available, welded strengths are based on data for combina- The compressive modulus of elasticity E given in Table tions of similar filler and base metal. Welding causes local annealing, which ASTM B 26 and B do not specify tensile yield erases this strength increase in a zone along both sides of strengths for some of the cast alloy-tempers they include the weld. The resulting variation in mechanical properties for example, sand cast These alloy-tempers in the vicinity of a weld is illustrated by the typical distri- are not included in Table A.
Moore, et al. There are also other alloy-tempers Table A. The welded therefore not included in this Specification. Welded yield strengths dimensional standards tolerances as do ASTM specifica- are for 0. The 2 tions for wrought products for example, B Therefore, in. Since the heat-affected zone extends approxi- Specification as those in the Aluminum Association Stan- mately 1 in.
The strengths specified in ASTM B 26 Table 2 for sand Welded compressive yield strengths Fcyw and welded castings are for separately cast test bars and not for the shear ultimate strengths Fsuw are derived from the relation- castings themselves. Section Therefore, the strengths given in Table A. Castings are more prone to discontinuities than wrought products.
Therefore, this Specification includes discontinu- ity standards for castings in order for them to be designed to the same Specification provisions as wrought products.
The quality standards are based on the following: ASTM B 26 and B section 20 both include options for liquid penetrant and radiographic inspection that may be specified by the purchaser.
Liquid penetrant inspection detects only surface flaws, so it is insufficient. ASTM B 26 and B only require radiographic inspection be per- formed if the purchaser specifies such inspection.
If such inspection is specified, the purchaser must also specify which of four quality grades A, B, C, or D must be met. Grade A allows no discontinuities at all; this is more stringent than wrought product quality levels and so it is unwarranted. When Grade D is specified, no tensile tests of coupons cut from castings are required. Therefore, only Figure CA. Standards and Data Table 6. Kaufman Figure 5. Standards for Aluminum Sand and Perma- in tensile fracture strength is required for notch sensitivity nent Mold Castings establishes four frequency levels for for these alloy-tempers and the tension coefficient kt is 1.
Inspection Level 2 requires A. Level 3 leaves the inspection filler metal comply with AWS A5. Tables M. Strengths given in Table A. B 26 allows the purchaser to require that the strength of coupons cut from production This Specification addresses only aluminum bolts.
B has the same requirement, but for certain alloy- This Specification addresses only aluminum rivets. The strengths This Specification addresses only aluminum screws.
This is because safety or resistance factors account for the fact that actual dimen- sions may be less than nominal dimensions, within the tol- B.
The torsion constant J may be determined as follows: B. Figure CB. An example of a serviceability limit state is a deflection beyond which the c For shapes containing open parts and closed parts, J is structure is unfit for service. An example of a strength limit the sum of J for the open parts and J for the closed parts. The design strength fRn is the product of the resistance factor f and the nominal strength Rn.
Resistance factors are less than or equal to 1. The basis for load and resistance factor design is given by Ellingwood, et al. The resistance of the struc- Figure CB.
Failure occurs when the resistance R is less than the load member limit states, 0. This fore, this Specification uses these resistance factors. This probability is a function of the difference between mean matches the AISC Specification for rupture and other value of the resistance and the mean value of the load effect member limit states. In Figure B. Because a column out-of-straightness factor of 0. His The safety factor for column local buckling has been work is summarized in Tables CB.
An out-of-straightness factor has not been applied LRFD. To do so, the relationship between safety factors to local buckling because the local buckling strength is not and resistance factors can be established as follows: sensitive to out-of-straightness Sharp Therefore, different buckling constant Table CB.
Table CB. The weld-affected zone in non-heat treatable alloys has linearly tapered thickness elements with d 2. The tapered flanges of American Standard channels in heat-treatable alloys has a strength slightly less than the and American Standard I beams meet this criterion. For this reason, buckling Three types of edge supports for elements with tapered constants for weld-affected zones of all alloys are determined thickness are addressed in Section B.
Section B. Kim provided the method used in this Section for c Tapered thickness elements supported on both edges Fig- determining the slenderness ratio for members that have ure CB. Once the slenderness ratio has been determined, use the B. The study by Sooi and Pekz used to establish these provisions was based on sheet metal shapes where the B. Therefore, this Speci- The strength of elements in uniform compression is the fication requires that the stiffener be at least as thick as the weighted average of the strengths of the unwelded and weld- element to be stiffened.
The strength of elements with The denominator in each of Equations B. The weld-affected zone for transverse welds that supported on both longitudinal edges Ra. Sooi and Pekz extend across the full width of an element is the gross area adapted the equations for Ra from the AISI Specification of the element.
The elastic buckling analysis by Sharp shows B. Galambos Figure 4. Equa- k2E 0. In columns buckling about a principal axis that is not an Stiffening bulbs and other complex shapes may provide axis of symmetry for example, channels buckling about greater strengths than those provided for in Section B. This is due to the non- linear post-buckling stress distribution in the sections ele- strength for these other shapes. Although some post-buckling strength may exist, it may not be as large as that if the buckling axis were an axis B.
Therefore, this Section limits the strength in with an Intermediate Stiffener such cases to the elastic local buckling strength. The provisions in this Section are based on Sharp , who developed an equation for flat elements supported on B. The buckling strength of actual shells, gular shapes Section F.
The equivalent slenderness ratio however, is strongly affected by imperfections in the geom- of 3. Tests indicate that this effect tends supported edge. The effect of imperfections Section B. The coefficients in the formula for inelastic buckling strength are assumed to be the same as for solid rectangu- B. The equivalent slenderness ratio Strengths determined using the provisions of this Sec- is 0. This is the optimum location for Section B. The resulting a more accurate assessment of element support conditions strength of the web is based on Bleich The stiff- can be used to determine the compressive strength.
The eners required moment of inertia is the same as that used use of Section B. The factor a accounts for the tion B. Sections B.
There- which a more accurate assessment of element support con- fore, only weld-affected zones in the compression portion ditions can be used to determine the compressive strength.
Kim showed that Section B. Further study is required to and B. The zone, which is not addressed by the Specification. The coefficients in the formula for inelastic buckling When Section F.
When the neutral axis is at the the strength of a stiffened element need not be limited to the mid-height of the element, the equivalent slenderness ratio strength of the stiffener since the elastic buckling strength is 0.
Simple support is assumed for all elements. Since elastic local buckling stresses. This inter- of elastic local buckling stresses is provided in Chapter B. Give your content the digital home it deserves. Get it to any device in seconds. Aluminum design manual free download. Publish for free today. APA 6th ed. Note: Citations are based on reference standards. However, formatting rules can vary widely between applications and fields of interest or study.
The specific requirements or preferences of your reviewing publisher, classroom teacher, institution or organization should be applied. The E-mail Address es field is required.
Please enter recipient e-mail address es. The E-mail Address es you entered is are not in a valid format. Please re-enter recipient e-mail address es.
You may send this item to up to five recipients. The name field is required. Please enter your name. The E-mail message field is required. Please enter the message. Please verify that you are not a robot. Would you also like to submit a review for this item? You already recently rated this item. Your rating has been recorded. Write a review Rate this item: 1 2 3 4 5. Preview this item Preview this item. Aluminum design manual : Author: Aluminum Association.
0コメント