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8/11/2019 Beam Design Manual
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Cold-Formed Steel
BeamDesign
Version 2.1
Load Carrying Capacity Beam Curves and Tables
Owners Manual
http://www.devstruc.com
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Index
About BeamDesign ...........................................................................................3
Installing BeamDesign ...................................................................................... 5
Main Window .....................................................................................................7
Materials Window ..............................................................................................8
Section Edit Window .........................................................................................9
BeamDesign Window ........................................................................................14
Options Window ................................................................................................23
Technical Considerations ..................................................................................24
Appendix ...........................................................................................................27
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About Cold-Formed Steel BeamDesign
Cold-Formed Steel BeamDesign is a friendly and powerful software for the design of
flexural members of Cold-Formed Steel, following AISI 2001 and 1996/99 Specifications.
The principal aim is to analyze a simple or continuous beam (2 to 4 equal spans) and to
determine the permitted load (Uniform or Concentrated Load allowed) carrying capacity,
while varying the span length (L). Also you can compare one section and two different
steels, or two sections with the same steel.
In this new version user is able to know the load-carrying capacity value for a specific span
length, being displayed these values in the References window.
ASD or LRFD approaches, determine Wall (W-allowable) or Wu (W-ultimate), showed by
Envelope Curves and Tables, or optionally their respectively seven Wi simple components
and Weq (Equivalent to Construction Load).
As efficient coefficients (W/Weight), for ratio between Load-Carrying Capacity and Full
Sectional Weight are giving by Envelope Tables, users can optimize designs, by choosing
their proper Section, Steel and restrictions.
Fourteen different sections are allowed (CS, CU, ZS, ZU, LS, LU, HU, RB, SB, IC, CC, IU,
TS, and TU), with selected Steels (16 ASTM Referenced Standards Steels are provided as
a guide). BeamDesign comes with the section dimensions from the AISI Manual for eachshape, and also user can create new section dimensions. In this new version we add tables
for the following manufacturers: Dietrich, Marino-Ware and SSMA.
Another feature from BeamDesign is you can calculate Geometric and Effective Properties
for provided sections and also for sections created by user.
All Curves and Tables are available for printing with the complete information on headers.
Besides engineers and other professionals, teachers and students also may be able to
profit the versatility of our sofware, changing optional parameters to obtain different curves
and tables or studying the Nominal Flexural Strength for Lateral Buckling Moment (Mnb)
versus L (Span Length) for different Shapes and Steels, or comparing CS and ZS curves
with AISI Design Manual Charts.
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Highlighted Options:
Supported Specifications
2001 AISI - US (ASD and LRFD)
2001 AISI - Canada (LSD)
1996/1999 AISI (ASD and LRFD)
Fya: increasing Fy (Virgin Yield Strength) value, due to cold work of forming.
Sections with Web Holes (only CS, CU, ZS, ZU, IC, IU and CC Sections).
Gravity or Uplift loads.
Uniform and Concentrated Load (L/2).
Fastened Flanges: Top, Bottom, both Top and Bottom or Unfastened Flanges.
Fastened to Support Flanges.
Bracings: Against lateral displacement and/or twisting.
One Flange Fastened to a Standing Seam Roof System.
Bearing Supports: Interior Laps; variable Widths and Web Stiffeners for
intermediate, end and/or interior Supports.
Variable Maximum Deflection Limit.
Beam Spacing.
Cb: Bending Coefficient for increasing Critical Buckling Strength.
Reference Span Length and Load Required can be modified by user.
Wi values are displayed for all curves, for required span length.
Units available in American Units and International Units. Units in feet and inches for Span Length.
Units for Uniform and Concentrated Load.
Calculate Geometric and Effective Section Properties.
Dimensional Limits for each Section.
Messages are given for exceeded limits such as b/t, d/t and h/t.
Curve Notes and Error Messages advise for correct AISI employment.
Databases for the following manufacturers: Dietrich, Marino-Ware and SSMA.
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Installing BeamDesign
System Requirements
Hardware requirements: 20 MB of available disk space. 56 MB of RAM.
Operating System: Microsoft Windows 98, NT, 2000, Me, XP, Vista and 7 (32 & 64 bits).
What's Inside?
After the download is complete, you will see a file named BeamDesign.exe in your
download location. Then just double click on the file and follow the steps in the installation
wizard.
The folder contains the application, the Library folder, a readme file and the BeamDesign
Manual. Inside the Library folder you will find Sections and Table files.
When user starts BeamDesign he will complete the register dialog box for personalizing his
copy.
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If your serial number is correct a copyright window will appear. After this the welcome
windows is displayed until you click mouse. It indicates the User Name, Company and
Version Type (Professional or Academic).
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Main Window
After the copyright window has been displayed, the main window will appear on screen.
Two groups, Sections and Materials and their respective tables are loaded.
AISI-Sections and ASTM-Steels are implemented with the program and loaded for the
first time, corresponding to tables founded in AISI Cold-Formed Steel Manual Design -
1996 Edition and AISI Cold-Formed Steel Manual Design - 2008 Edition.
Many tables of each group can be stored in Library folder. Last tables used, are loaded
when the user starts up. The Library folder should not be erased or changed its name.
Also new Sections and Materials files created should be saved within the Library folder.
The main window contains two different groups (Sections and Materials) and the Beam
Design button. Inside the groups you will find another two buttons. The Change Table
button lets you change the table loaded in default, and select other table from the Library
folder. The Edit Table button call the Section Edit and the Materials Edit windows.
The allowable units for tables are:
a) Sections Tables: in inches or mm millimeters.
b) Steels Tables: ksi or MPa.
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Materials Window
First Column (x) set active or inactive the Standard Specifications you want to use with the
program.
The Change button modifies only the editable fields: Modulus E and G.
The allowable units are:
a) Steels Properties in International Units (SI) - MPa.
b) Steels Properties in American Units (US) - ksi.
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Section Edit Window
This window shows selected sections and materials, geometric and effective properties,
Increased Strength (Fya) and Weight (wt). Also shows options for units (SI or US), holes
and section drawing.
Selecting Section
The sections are arranged in the library in groups. Each of the groups consists of arange of sections of a similar type.
Menu shows the allowable Sections:
CS, CU, ZS, ZU, LS, LU, HU, BR, BS, IC, IU, TS, TU and CC.
Simple Sections
CS (Stiffened Channel), CU (Unstiffened Channel), ZS (Stiffened Zeta), ZU(Unstiffened Zeta), HU (Hat), LS (Stiffened Angle), LU (Unstiffened Angle), BR
(Rectangular Box), BS (Square Box).
Composed Sections
IC (two CS Back to Back), IU (two CU Back to Back), TS (two LS Back toBack), TU (two LU Back to Back), CC (two CS Face to Face).
LS, LU and TU are considered only for Section Properties Calculations.
Selecting Sections
Choose the Section by its ID (Identification).
Dimensions and properties are displayed.
Selecting Referenced Steels
Select the steel, and the following properties changes:
Effective Modulus (Se), Effective Inertia (Ie), Full Section Tensile Yield StrengthIncreased, top and bottom, (Fya t) and (Fya b), and if the section is compact.
Drawing Section (Help)
Shows Section Parameters when helpis checked.
Shows a Scale Drawing when helpis not checked.
(SC) Shear Center (CG) Centoid.
Hole Options
If Holes is checked, Section Properties are calculated considering Holes.
Units
Shows Properties in International Units (SI).
Shows Properties in American Units (US).
Additional information
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Units of Table for Sections
Units of Table for Steels
Virgin Yield Strength (Fy)
Virgin Ultimate Tensile Strength (Fu)
Fu / Fy ratio
EditableFields
1) Section Name (ID)Dimensions
2) A= Depth of Section
3) B= Flange Width
4) C= Overall Depth of Lip
5) t= Section Thickness>= 0.89mm (35mils) (Also available Gage units)
6) Ri= Inside Bend Radius
7) ga= Angle between a Flange and its edge stiffener
8) do / dh: Diameter (do) or Depth (dh) of Web Hole. do/h
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Sx top= Effective Section Modulus - Compression Top
Sx bot= Effective Section Modulus - Compression Bottom
Iex= Effective Moment of Inertia for Deflection
Fya top= Full Section Tensile Yield Strength (Increased) - Compression Top
Fya bot= Full Section Tensile Yield Strength (Increased) - Compression Bottom
Compact=Compact Compression Flange - Ro=1
wt=Full Sectional Weight
Error Messages
Section DOESN'T VERIFY Geometric Conditions:
Ratio (Flange Flat Width/Thickness) w/t> 60
Ratio (Web Depth/Thickness) h/t> 200
Thickness t< 35 mils (0.89 mm)
Ratio w/t> 500
Ratio Ri/t> 6
Ratio h/t> 200
Ratio c/t> 14Ratio do/h> 0.7
Holes Diagonal
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Section Edit Screenshots
1) Section 9CS3x075
2) Section 8ZS2.5x075
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3) Section 3HU4.5x135
4) Section I9CS3x075
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BeamDesign Window
BeamDesign analyzes a simple or continuous beam and determines the permitted Uniform
Load (W) or Concentrated Load (P) Carrying Capacity, while varying the span length (L). By
default W units are (kips/ft) or (kN/m).
Calculated values (W, L) or (P, L) are represented by Curves and Tables.
Select Sections
Menu allows selecting ten (10) possible sections for curves and tables:
CS, CU, ZS, ZU, HU, BR, BS, IC, IU, TS, TU, CC.
Analysis Method (AISI 2001 and AISI 1996/99)
ADS Approach: Allowable Design Strength for Allowable Loads (Wall).
LRFD Approach: Load and Resistance Factor Design for Ultimate Loads (Wu).
LSD Approach: Limit States Design for Ultimate Loads (Wu).
For LRFD and LSD see Options windows with suggested Load Factors. By default,
for Construction Load (g= 1.4) and for Deflection (g= 1.6).
Units
Uniform Load
t/m, kg/m, KN/m, N/m, t/cm, kg/cm, KN/cm, N/cm, kip/in, kip/ft, lbf/ft (plf), lbf/in
Concentrated Loadtn, kg, kN, N, kip, lbf
Holes
CheckHolesfor Central Web Holes allowed for seven sections: C, U, Z, ZU, IC, IUand CC. Holesbutton is available if the hole diameter was previously changed inthe Section Edit window.
Clear Distances between Holes >=18 in. (457mm)
Clear Distances between First Hole to Edge Support>= A' (A'=Depth of the Section).
See Editable Fields (8) at Section Edit for more information.
Envelope and Simple Curves
Check Envelopefor Uniform Load Beam Capacity (Wall. or Wu.) versus SpanLength (L).
Otherwise program draws Simple Load Curves W (1 to 7) and Curve (8*) Weq.
Curve (9*) Mn will be drawn only if was checked in Options
Load Capacity Due to:
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Bending Only
Bending for lateral Buckling
Shear Only for End Reaction
Shear or Shear + Bending for Interior Reaction
Web Crippling (W.C.) for End Reaction
W.C. or W.C. + Bending for Int. Reaction
Maximum Deflection
8*) Equivalent to Construction Load
9*) Curve Mnb= Nominal Flexural Moment
Compare Sections
If you select 1 Section, Curves 1 and 2 are drawing for Steels 1 and 2.
If you select 2 Sections, Curves 1 and 2 are drawing with Steel 1
Checking AS, program show all dimensions for all sections in the listbox. So you
can compare a C-Section dimension with a U-Section dimension.
Otherwise program show only dimensions for the selected section.
Use Fya
Check Fyadue to cold work of forming, for increasing Fy value.
Fya (Average Yield point of Steel in the full section).
Steel Menu
Select Steel 1 for Curve 1.
Select Steel 2 for Curve 2.
Disable Steel 2 (Steel 2 for Curve 2 = Steel 1 for Curve 1).
Selecting Span number
From 1 to 4 Spans of a Continuous Beam.
Fixing Cb Value
FixCbValue= 1
Otherwise Cb>= 1 is calculated. Cb is a Bending Coefficient dependent on FlexuralMoment Gradient that increases Critical Buckling Strength.
Beam Deflection
If Deflection is Considered, inputMaximum Deflection Limit= ratio Length /MaximumDeflection.
Default value = 240.
Beam Spacing
If Beam Spacing 1m (ft), Load Carrying Capacity Units (Wall or Wu) are kN/m2 orkips/ft2.
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Default value= 1m (ft), Load Carrying Capacity Units (Wall or Wu) are kN/m orkips/ft.
Specific Span Length for a Beam
In this new version user is able to know the load-carrying capacity value for a
specific Span Length.
In the Referencesbox are displayed the values of the required load and the Wivalues of the load-carrying capacity corresponding to desired span length.
Inside the Curves window the Wr is displayed through a triangle. For making the
comparison between Wr and Wi, the triangle icon has three states:
Green: the required load by the user is lower than load-carrying capacity for the two
steels (Section verifies - OK).
Yellow: the required load by the user is lower than load-carrying capacity for one
steel. (Section doesnt verify for steel 1 Section verifies for steel 2)
Red: the required load by the user is higher than load-carrying capacity for the twosteels. (Section doesnt verify NOT OK).
These values are also displayed in the Referenceswindow (Sr and Wr).
Reference Span Length
Write a desired Span Length.
Required Load
Write a desired Load.
Span Length Range
From: Initial length value for drawing curves and calculating tables.
To: End length value for drawing curves and calculating tables.
Show range in inches and feet.
Load Cases
Uniform Load
Concentrated Load (L/2)
Gravity (Beam Weight Included)
Suction (UpLift) - (Beam Weight Included)
Fastened Flange
Free Flange
Top Fastened Flange (See different advices with Curves)
Bottom Fastened Flange (See different advices with Curves)
Both Fastened Flanges
Stiffeners
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Check Es, In or/and Isfor Web Stiffeners, against Web Crippling, for increasingLoad Carrying Capacity.
Es:Web Stiffener at End Support.
In:Intermediate Web Stiffeners.
Is:Web Stiffener at Interior Support.
Notes:advice the Span Length Limit for economical Stiffener use.
Bracings
Check yfor Lateral Bracings (Against Lateral Deflection) y Direction isperpendicular to Load Direction.
Checkt for Rotational Bracings (Against Twisting)
For Fix Point button disabled:
Case 1 - Number: Number of Bracings for each Span (Recommended
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Menu
The program shows Page Setup Dialog and selects the Paper size and orientationand margins.
Table Forms: select Vertical orientation
Curve Drawings: select Landscape orientation
Options
Open the Optionswindow.
Sections Table and Materials Table
Openthe Sections and Materials window (You can not make changes in this tables,it is only for consult).
Users Guide
Openthe Users Guide in Adobe Acrobat Reader (Keyboard Shortcut is F1).
Check for Updates
Check if there are new versions of BeamDesign available for download.
Contextual Menu
Show/Hide:
References
Beam Icon
Section IconChange Curves Line Thickness
References Lines Wr
Change Color Curves
Call windows:
Options
Advises with Curves
Users must fulfill the Following Conditions for:
Laps at Support Not Convenient (For Economy).
Tension Fastened Flange: See Appendix A (9 to 15).
End Support Member Thickness>= 3/16 (4.76mm).
Interior Support for two Nested Z: See Appendix B.
Web Stiffener at End Support: B 6.1 (all).
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Web Stiffener at Interior Support: B 6.1 (all).
Headers for Curves and Tables
First Line: Type of Curve, Specifications, Approach Method, Load-Length and Units,
Section name and/or Steel (Fy/Fya), for Simple or Envelope Curve, respectively.
Second Line: Span Number, Loads (Presion or Uplift), Laps Length (%L), Beam
Spacing, Flanges (Free or Fastened), Bracings.
Third Line: Web Stiffeners at Supports (Considered or Not), Hole (Considered or
Not).
Fourth Line: Maximum Deflection Limit (or Not Considered), Cb (Bending
Coefficient).
Complementary Drawings for Curves
Icons for Sections in scale: Drawing Sections, Bracings (y and t) and Fastened
Flanges (Top and/or Bottom).Beam Diagram View: Span Number, Gravity or Uplift Loads, Laps (if any), Bracings
(if any).
For simple curves, dotted lines indicate that they are not included in envelope
curves.
The possible cases are:
a) W5 - With Web Stiffener at end Support.
b) W6 - With Web Stiffener at interior Support.
c) W7 Maximum Deflection not considered.d) W8 Equivalent to Construction Load (always in dotted line).
Display Tables
Envelope
W-env.1 and W-env.2show values from Curve 1 and Curve 2 respectively.
Simple governing causes (W1 to W7) witch determined the minor Load Carrying
Capacity for each case are given, and efficiencies W-env.1/Wt and W-env.2/Wt,
and the relative efficiency W-env.2/W-env.1are so written.
If W-env.1 and W-env.2values are minor to W8 (Equivalent to Construction Load),
text changes to Italic Style.
Simple Curves
Simple Curves and (W8) are also given in tables.
Governing values are all painted to highlight them (green). If some of these values
are minor to W8, color changes (red).
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Curves and Tables Screenshots
Example I: Four Span Continuos ZS Purlin Design ASD Method 2001
Envelope Curves for ZS Section with Fy1=55ksi, Fy2=33ksi
Envelope Tables for ZS
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Simples Curves for ZS Section
Simple Tables for ZS Section
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Example II: C-Section without Lips Braced At Mid-span, and Web Stiffeners at Supports
Envelope Curves for 5.5CU1.25x057 Section with Fy1=33ksi, Fy2=50ksi
Envelope Tables for CU Section
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Simples Curves for CU Section
Simple Tables for CU Section
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Options Window
Simples Curves
Simple Curves are grouped as:
a) Load Carrying Capacity (W1 to W7) and Equivalent Construction Load(W8) Curves.
b) Mnb-Nominal Flexural Moment.Check let active a) or b) group and to select each Wi.
Unselected curves are not showed in graphics (in zoom mode E, F; in mode Rsimple curves are all showed).
Show
Show or Hide: References, Beam and Section Icons, Gross line for drawings and
References Lines for Wr.
Load Factors
Change default value for Deflection and Construction Load.
Span Length Range Units
Check for show units in feet.
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Technical Considerations
Cold-Formed Steel BeamDesign for flexural members of CFS, was entirely conceived
following AISI 2001 and 1996/99 Specifications.
Certainly, some practical restrictions were introduced:
1. Beams are supposed simple or continuous elements over fixed supports. They will befirmly connected to both the top and the bottom flanges, to prevent from twisting andlateral bending at the ends of each span.
2. Fastened Flange, means that these compression flange, (bottom or top), is throughattached to a rigid plane diaphragm (deck or sheathing) over (or under) the flange,(seeAISI 96 Section D, for more information), to effectively restrain the flange against
twisting and lateral bending all along the beam.
3. Beams (C or Z shapes) having the tension flange attached as Section C3.1.3 states(Fourteen conditions), with the compression flange laterally unbraced, are partiallyrestrained against lateral bending. Factors R= 1.2 and Ri/t=1, for all the different segments andchooses for all the beam, the worst combination of Cb with it respective bending
length. Maximum Cb=2.3 (adopted).
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8. Load Carrying Capacity Wall or Wu are calculated by ASD or LRFD Method. Wall.gives the envelope Allowable Uniform Load, for six nominal design strengths,(additionally a seventh limitation, for beam deflection is considered), divided by theircorresponding specified safety factors W.
9. Wu gives the envelope Ultimate Design Uniform Load, for six nominal resistances,(additionally an equivalent one for beam deflection is considered), multiplied by theircorresponding specified resistance factors . Wu must be confronted with the differentload combinations of required uniform strength for factored loads (or requiredresistance). AISI96 recommendations, (Section A4), are based on ANSI/ ASCE 7
Specifications.
10. Loads for Nominal Strengths or Resistances: Simple Curves and Tables.
W1 - Bending Only
W1- L Curve (or table) gives Load Carrying Capacity, for the Nominal Strength forBending, with lateral buckling restricted. Procedure I (Sec.3.1.1.), was chosen forMn=Se.Fy, with Se, (effective section modulus) calculated with the extreme fiber at Fy.
W2 - Bending for lateral Buckling
W2- L Curve (or Table) gives Load Carrying Capacity for the Nominal Strength forBending (Mnb), with lateral buckling. Mnb=Sc.Fc, with Sc, (Effective Section Modulus)calculated with the extreme compression fiber at Fc (elastic or inelastic CriticalStress)=Mc/Sf, with Sf (Full Section Modulus), (Sfx for all, except H sections withrotated axis), and Mc, Critical Moment for Lateral-torsional buckling.
a) Critical Stress Fc is calculated for open cross sections members, C-Channels, I-Beams and Z-Beams,(singly, doubly and point symmetric sections), with twisting andlateral displacement as an unity, for lateral-torsional buckling, following Sec.C3.1.2.1 of
the 1999 AISI Supplement. (Procedure a).
b) Critical elastic Stress Fe in lieu of Fc, is calculated for closed box-type member
sections BR and BS (Square and rectangular boxes), following Sec.C3.1.2.2 of the1999 AISI Supplement.
c) Design Stress Fb2 in lieu of Fc, is calculated for member sections H (Hat orinverted hat), where compression flanges tend to buckle separately accompanied byout-of-plane bending of the web, following the simplified analysis, in Sec.2 of Part II, of
the 1996 AISI Design Manual.
For 1999 AISI Supplement when the depth of holes do/h>=0.38, effective width shallbe determined by section B.3.1(a).
W3 - Shear Only for End Reaction
W3- L Curve (or Table) gives Load Carrying Capacity for the Nominal Strength forShear (Vn) only on end support (e), always without attached transverse web stiffenersprovided.1999 AISI Supplement gives reduction coefficient qs to multiply Vn.for C sections withholes.
W4 - Shear or Shear + Bending for Interior Reaction
W4- L Curve (or Table) gives Load Carrying Capacity for the Nominal Strength forShear (Vn) only or Combined Shear and Bending, on interior support, (i), alwayswithout attached transverse web stiffeners provided. Program chooses minor value for
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W4, and indicates it and also which the governing cause is, on Tables. When laps areconsidered, as lap lengths are limited, Shear values for one web are dominating.
W5 - Web Crippling for End Reaction
W5- L Curve (or Table) gives Load Carrying Capacity for the Nominal Strength forWeb Crippling (Pn), only on end support (e), for EOF (End One Loading) according toSection C3.4.For the end support of a Z-shape, if the flange is bolted, and both the support and thesection satisfied the requirements at 3.4, Pn value would be increased, multiplied by1.3.
W6 - Web Crippling or Web Crippling + Bending for Interior Reaction
W6- L Curve (or Table) gives Load Carrying Capacity for the Nominal Strength forWeb Crippling (Pn), only or Combined Web Crippling and Bending, on interiorsupport, (i) for IOF (Interior One Flange Loading) according to Section C3.4. Programchooses minor value for W6, and indicates it, and also which the governing cause is,on Tables.For the support point of two nested Z-shapes, if all required conditions at C.3.5.1 weresatisfied, Load Carrying Capacity would be increased.
For calculating W5 and W6, different equations are given on Table 3.4-1, by 1996 AISISpecifications, for single Unreinforced Webs, or for I (two C connected back to backaccording to D1.1) and similar sections.1999 AISI Supplement gives reduction coefficient Rc to multiply Pn for C sections withholes.Web Stiffeners built according to Art. B6-1, at each support (Se or/and Si) are optionaltools for eliminating Crippling problem.Program advices the economic lengths for the beam, in order to use the web stiffenersat each support.
W7 - Equivalent for Maximum Deflection
W7- L Curve (or Table) gives optionally the Equivalent Uniform Load CarryingCapacity for an imposed Maximum Deflection service condition, as a fraction of thespan Length (e.g. L/240).For LRFD Method Load Factor is assumed equal to 1.50, by default.
W8 - Equivalent to Construction Load
W8- L Curve (or Table) gives optionally the Equivalent Uniform Load for an imposedConcentrated Construction Load= 1KN or 0,22 kips applied at the worst situation, andas a service condition.For LRFD Method Load Factor is assumed equal to 1.40, by default.
Mnb= Nominal Flexural MomentMnb-L Curve gives optionally the Nominal Strength for Bending with lateral bucklingversus the span length, for any or none lateral restriction.For example, if User fixes Cb=1 with free flanges and no bracings, for C and Z shapes,with Fy=33ksi and Fy=50ksi steels, He obtains Chart II-1a to 2b from the AISI 96Design Manual.
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Appendix
Appendix A
According to AISI 2001 Specification, Chapter C3.1.3.
The reduction factor, R, shall be limited to roof and wall systems meeting the followingconditions:1) Member depth less than 11.5 in. (292 mm)
2) Member flanges shall have edge stiffeners3) 60 "depth/thickness "1704) 2.8 "depth/flange "4.55) 16 "flat width/thickness of flange "436) For continuous span systems, the lap length at each interior support in each
direction (distance from center of support to end of lap) shall not be less than 1.5d.7) Member span length shall be no greater than 33 feet (10 m)8) For continuous span systems, the longest member span length shall not be more
than 20% greater than the shortest length.9) Both flanges shall be prevented from moving laterally at the supports.10) Roof or wall panels shall be steels sheets with 50 ksi (640 MPa or 3520 kg/cm2)
minimum yield point, and a minimum of 0.018 in. (0.46 mm) base metal thickness,
having a minimum rib depth of 1-1/4 in. (32 mm), spaced a maximum of 12 in. (305mm) on centers and attached in a manner to effectively inhibit relative movementbetween the panel and purlin flange.
11) Insulation shall be glass fiber blanket 0 to 6 in. (152 mm) thick compressedbetween the member and panel in a manner consistent with the fastener beingused.
12) Fastener type: minimum no. 12 self-drilling or self-tapping sheet metal screws of3/16 in. (4.76 mm) rivets, having washers #in. (12.7 mm) diameter.
13) Fasteners shall not be standoff type screws.14) Fasteners shall be spaced not greater than 12 in (305 mm) on centers and placed
near the center of the beam flange, and adjacent to panel high rib.15) The design yield point of the member shall not exceed 60 ksi (410 MPa or 4220
kg/cm2).
Appendix BAccording to AISI 2001 Specification, Chapter C3.5.1.
The following conditions shall be satisfied:1) The ends of each section shall be connected to the other section by a minimum of
two #in. (12.7 mm) diameter A307 bolts trough the web.2) The combined section shall be connected to the support by minimum of two # in.
(12.7 mm) diameter A307 bolts trough the flanges.3) The webs of two sections shall be in contact.4) The ratio of the thicker to the thinner part shall not exceed 1.3.