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The fixed length studs (TLF) are ordered to length, are single piece components, and are swaged at each end to interlock with the TRAKLOC® Track. This product is used in applications where the partition height is consistent and speed of installation is of critical importance. The unique swage at the end of each stud allows for quick, tight installation eliminating the need for framing screws or a lift/ladder to install the framing screws.
Unit of Measure

Specifications

Brands

 N/A A-1 Alloys ClarkDietrich® TRAKLOC®

Elevator Stud Section Properties

Design Thickness

 N/A 0.0312 in

Yield Strength

 N/A 33 ksi

Area

 N/A 0.167 in²

Weight

 N/A 0.57 lb/ft

Gross Section Properties (lx)

 N/A 0.171 in4

Gross Section Properties (Sx)

 N/A 0.137 in³
Gross Section Properties (Rx)1 N/A 1.011 in

Gross Section Properties (ly)

 N/A 0.035 in4

Gross Section Properties (Ry)

 N/A 0.461 in

Effective Section Properties at Tensile Strength (Fy) (Ae)

 N/A 0.113 in²

Effective Section Properties at Tensile Strength (Fy) (lx)

 N/A 0.170 in4

Effective Section Properties at Tensile Strength (Fy) (Sx)

 N/A 0.125 in³
Effective Section Properties at Tensile Strength (Fy) (Mal)2 N/A 2475 in·lb
Effective Section Properties at Tensile Strength (Fy) (Mad)3 N/A 2515 in·lb

Effective Section Properties at Tensile Strength (Fy) (Vag)

 N/A 832 lb

Effective Section Properties at Tensile Strength (Fy) (Vanet)

 N/A 388 lb

Stud/Track End Reaction (Rx)

 N/A 106 lb

Torsional Properties (Jx1000)

 N/A 0.0543 in4

Torsional Properties (Cw)

 N/A 0.049 in6

Torsional Properties (Xo)

 N/A -0.984 in

Torsional Properties (m)

 N/A 0.590 in

Torsional Properties (Ro)

 N/A 1.485 in

Torsional Properties (ß)

 N/A 0.560 Beta

Length (Lu)

 N/A 31.4 in

TRAKLOC® Composite Limiting Heights with 5/8 Inch (in) Type X Gypsum Board

Width

 N/A 2-1/2 in

Spacing

 N/A 12 in16 in24 in

Composite Limiting Height (L/120) at 5 Pounds Per Square Foot (PSF) Pressure and 12 Inch (in) Spacing

 N/A 18 ft 5 in.

Composite Limiting Height (L/240) at 5 Pounds Per Square Foot (PSF) Pressure and 12 Inch (in) Spacing

 N/A 16 ft 0 in.

Composite Limiting Height (L/360) at 5 Pounds Per Square Foot (PSF) Pressure and 12 Inch (in) Spacing

 N/A 14 ft 0 in.

Composite Limiting Height (L/120) at 7.5 Pounds Per Square Foot (PSF) Pressure and 12 Inch (in) Spacing

 N/A 16 ft 2 in.

Composite Limiting Height (L/240) at 7.5 Pounds Per Square Foot (PSF) Pressure and 12 Inch (in) Spacing

 N/A 14 ft 0 in.

Composite Limiting Height (L/360) at 7.5 Pounds Per Square Foot (PSF) Pressure and 12 Inch (in) Spacing

 N/A 12 ft 3 in.

Composite Limiting Height (L/120) at 10 Pounds Per Square Foot (PSF) Pressure and 12 Inch (in) Spacing

 N/A 14 ft 9 in.

Composite Limiting Height (L/240) at 10 Pounds Per Square Foot (PSF) Pressure and 12 Inch (in) Spacing

 N/A 12 ft 8 in.

Composite Limiting Height (L/360) at 10 Pounds Per Square Foot (PSF) Pressure and 12 Inch (in) Spacing

 N/A 11 ft 2 in.

Composite Limiting Height (L/120) at 5 Pounds Per Square Foot (PSF) Pressure and 16 Inch (in) Spacing

 N/A 17 ft 6 in.

Composite Limiting Height (L/240) at 5 Pounds Per Square Foot (PSF) Pressure and 16 Inch (in) Spacing

 N/A 15 ft 0 in.

Composite Limiting Height (L/360) at 5 Pounds Per Square Foot (PSF) Pressure and 16 Inch (in) Spacing

 N/A 13 ft 2 in.

Composite Limiting Height (L/120) at 7.5 Pounds Per Square Foot (PSF) Pressure and 16 Inch (in) Spacing

 N/A 15 ft 4 in.

Composite Limiting Height (L/240) at 7.5 Pounds Per Square Foot (PSF) Pressure and 16 Inch (in) Spacing

 N/A 13 ft 1 in.

Composite Limiting Height (L/360) at 7.5 Pounds Per Square Foot (PSF) Pressure and 16 Inch (in) Spacing

 N/A 11 ft 6 in.

Composite Limiting Height (L/120) at 10 Pounds Per Square Foot (PSF) Pressure and 16 Inch (in) Spacing

 N/A 13 ft 11 in.

Composite Limiting Height (L/240) at 10 Pounds Per Square Foot (PSF) Pressure and 16 Inch (in) Spacing

 N/A 11 ft 11 in.

Composite Limiting Height (L/360) at 10 Pounds Per Square Foot (PSF) Pressure and 16 Inch (in) Spacing

 N/A 10 ft 6 in.

Composite Limiting Height (L/120) at 5 Pounds Per Square Foot (PSF) Pressure and 24 Inch (in) Spacing

 N/A 15 ft 9 in.

Composite Limiting Height (L/240) at 5 Pounds Per Square Foot (PSF) Pressure and 24 Inch (in) Spacing

 N/A 13 ft 5 in.

Composite Limiting Height (L/360) at 5 Pounds Per Square Foot (PSF) Pressure and 24 Inch (in) Spacing

 N/A 11 ft 10 in.

Composite Limiting Height (L/120) at 7.5 Pounds Per Square Foot (PSF) Pressure and 24 Inch (in) Spacing

 N/A 13 ft 9 in.

Composite Limiting Height (L/240) at 7.5 Pounds Per Square Foot (PSF) Pressure and 24 Inch (in) Spacing

 N/A 11 ft 9 in.

Composite Limiting Height (L/360) at 7.5 Pounds Per Square Foot (PSF) Pressure and 24 Inch (in) Spacing

 N/A 10 ft 4 in.

Composite Limiting Height (L/120) at 10 Pounds Per Square Foot (PSF) Pressure and 24 Inch (in) Spacing

 N/A 12 ft 6 in.

Composite Limiting Height (L/240) at 10 Pounds Per Square Foot (PSF) Pressure and 24 Inch (in) Spacing

 N/A 10 ft 8 in.

Composite Limiting Height (L/360) at 10 Pounds Per Square Foot (PSF) Pressure and 24 Inch (in) Spacing

 N/A 9 ft 3 in.

Notes for Composite Limiting Height

 N/A
  • Allowable composite limiting heights were determined in accordance with ICC-ES AC86-2012.
  • Additional composite wall testing and analysis requirements of the SFIA Code Compliance Certification Program were observed.
  • In accordance with current building codes and AISI design standards, the 1/3 Stress Increase for strength was not used.
  • The composite limiting heights provided in the tables are based on a single layer of 5/8" Type X Gypsum Board complying with ASTM C1396 and from the following manufacturers: American Gypsum, CertainTeed, Georgia Pacific, Continental, National Gypsum or USG.
  • The gypsum board must be applied full height in the vertical orientation to each stud flange and installed in accordance with ASTM C754 using minimum No. 6 Type S fine thread Drywall bugle head screws spaced as listed below:
  • Screws spaced a maximum of 16 inch on-center to framing members spaced at 12 inch on-center.
  • Screws spaced a maximum of 12 inch on-center to framing members spaced at 16inch or 24 inch on-center.
  • Screws spaced 16 inch on-center to the top and bottom track.
  • No fasteners are required for attaching the stud to the track except as detailed in ASTM C754.
  • Stud end bearing must be a minimum of 1 inch.
  • The minimum overlap of the TSO (Outer Stud) and TSE (Inner Stud) must be 8 inches and the maximum un-lapped length of the TSE must be 4 inches.

TRAKLOC® Fully Braced Non-Composite Limiting Heights

Fully Braced Non-Composite Limiting Height (L/120) at 5 Pounds Per Square Foot (PSF) Pressure and 12 Inch (in) Spacing

 N/A 16 ft 5 in.

Fully Braced Non-Composite Limiting Height (L/240) at 5 Pounds Per Square Foot (PSF) Pressure and 12 Inch (in) Spacing

 N/A 13 ft 1 in.

Fully Braced Non-Composite Limiting Height (L/360) at 5 Pounds Per Square Foot (PSF) Pressure and 12 Inch (in) Spacing

 N/A 11 ft 5 in.

Fully Braced Non-Composite Limiting Height (L/120) at 7.5 Pounds Per Square Foot (PSF) Pressure and 12 Inch (in) Spacing

 N/A 14 ft 10 in.

Fully Braced Non-Composite Limiting Height (L/240) at 7.5 Pounds Per Square Foot (PSF) Pressure and 12 Inch (in) Spacing

 N/A 12 ft 10 in.

Fully Braced Non-Composite Limiting Height (L/360) at 7.5 Pounds Per Square Foot (PSF) Pressure and 12 Inch (in) Spacing

 N/A 11 ft 3 in.

Fully Braced Non-Composite Limiting Height (L/120) at 10 Pounds Per Square Foot (PSF) Pressure and 12 Inch (in) Spacing

 N/A 12 ft 10 in.

Fully Braced Non-Composite Limiting Height (L/240) at 10 Pounds Per Square Foot (PSF) Pressure and 12 Inch (in) Spacing

 N/A 11 ft 8 in.

Fully Braced Non-Composite Limiting Height (L/360) at 10 Pounds Per Square Foot (PSF) Pressure and 12 Inch (in) Spacing

 N/A 10 ft 2 in.

Fully Braced Non-Composite Limiting Height (L/120) at 5 Pounds Per Square Foot (PSF) Pressure and 16 Inch (in) Spacing

 N/A 14 ft 11 in.

Fully Braced Non-Composite Limiting Height (L/240) at 5 Pounds Per Square Foot (PSF) Pressure and 16 Inch (in) Spacing

 N/A 11 ft 10 in.

Fully Braced Non-Composite Limiting Height (L/360) at 5 Pounds Per Square Foot (PSF) Pressure and 16 Inch (in) Spacing

 N/A 10 ft 4 in.

Fully Braced Non-Composite Limiting Height (L/120) at 7.5 Pounds Per Square Foot (PSF) Pressure and 16 Inch (in) Spacing

 N/A 12 ft 10 in.

Fully Braced Non-Composite Limiting Height (L/240) at 7.5 Pounds Per Square Foot (PSF) Pressure and 16 Inch (in) Spacing

 N/A 11 ft 8 in.

Fully Braced Non-Composite Limiting Height (L/360) at 7.5 Pounds Per Square Foot (PSF) Pressure and 16 Inch (in) Spacing

 N/A 10 ft 2 in.

Fully Braced Non-Composite Limiting Height (L/120) at 10 Pounds Per Square Foot (PSF) Pressure and 16 Inch (in) Spacing

 N/A 11 ft 1 in.

Fully Braced Non-Composite Limiting Height (L/240) at 10 Pounds Per Square Foot (PSF) Pressure and 16 Inch (in) Spacing

 N/A 10 ft 7 in.

Fully Braced Non-Composite Limiting Height (L/360) at 10 Pounds Per Square Foot (PSF) Pressure and 16 Inch (in) Spacing

 N/A 9 ft 3 in.

Fully Braced Non-Composite Limiting Height (L/120) at 5 Pounds Per Square Foot (PSF) Pressure and 24 Inch (in) Spacing

 N/A 12 ft 10 in.

Fully Braced Non-Composite Limiting Height (L/240) at 5 Pounds Per Square Foot (PSF) Pressure and 24 Inch (in) Spacing

 N/A 10 ft 4 in.

Fully Braced Non-Composite Limiting Height (L/360) at 5 Pounds Per Square Foot (PSF) Pressure and 24 Inch (in) Spacing

 N/A 9 ft 1 in.

Fully Braced Non-Composite Limiting Height (L/120) at 7.5 Pounds Per Square Foot (PSF) Pressure and 24 Inch (in) Spacing

 N/A 10 ft 6 in.

Fully Braced Non-Composite Limiting Height (L/240) at 7.5 Pounds Per Square Foot (PSF) Pressure and 24 Inch (in) Spacing

 N/A 10 ft 2 in.

Fully Braced Non-Composite Limiting Height (L/360) at 7.5 Pounds Per Square Foot (PSF) Pressure and 24 Inch (in) Spacing

 N/A 8 ft 11 in.

Fully Braced Non-Composite Limiting Height (L/120) at 10 Pounds Per Square Foot (PSF) Pressure and 24 Inch (in) Spacing

 N/A 9 ft 1 in.

Fully Braced Non-Composite Limiting Height (L/240) at 10 Pounds Per Square Foot (PSF) Pressure and 24 Inch (in) Spacing

 N/A 9 ft 1 in.

Fully Braced Non-Composite Limiting Height (L/360) at 10 Pounds Per Square Foot (PSF) Pressure and 24 Inch (in) Spacing

 N/A 8 ft 1 in.

Notes for Fully Braced Non-Composite Limiting Height

 N/A
  • Heights are based on AISI S100-07 with S2-10 Supplement, and AISI S100-12 Specification using steel properties alone.
  • Compression flange must be continuously braced.
  • End bearing must be 1 inch.
  • The minimum overlap of the TSO (Outer Stud) and TSE (inner Stud) must be 8 inches and the maximum un-lapped length of the TSE must be 4 inches.

TRAKLOC® 48 Inch (in) O.C. Bracing Non-Composite Limiting Heights

48 Inch (in) O.C. Bracing Non-Composite Limiting Height (L/120) at 5 Pounds Per Square Foot (PSF) Pressure and 12 Inch (in) Spacing

 N/A 16 ft 5 in.

48 Inch (in) O.C. Bracing Non-Composite Limiting Height (L/240) at 5 Pounds Per Square Foot (PSF) Pressure and 12 Inch (in) Spacing

 N/A 13 ft 1 in.

48 Inch (in) O.C. Bracing Non-Composite Limiting Height (L/360) at 5 Pounds Per Square Foot (PSF) Pressure and 12 Inch (in) Spacing

 N/A 11 ft 5 in.

48 Inch (in) O.C. Bracing Non-Composite Limiting Height (L/120) at 7.5 Pounds Per Square Foot (PSF) Pressure and 12 Inch (in) Spacing

 N/A 13 ft 9 in.

48 Inch (in) O.C. Bracing Non-Composite Limiting Height (L/240) at 7.5 Pounds Per Square Foot (PSF) Pressure and 12 Inch (in) Spacing

 N/A 12 ft 10 in.

48 Inch (in) O.C. Bracing Non-Composite Limiting Height (L/360) at 7.5 Pounds Per Square Foot (PSF) Pressure and 12 Inch (in) Spacing

 N/A 11 ft 3 in.

48 Inch (in) O.C. Bracing Non-Composite Limiting Height (L/120) at 10 Pounds Per Square Foot (PSF) Pressure and 12 Inch (in) Spacing

 N/A 11 ft 11 in.

48 Inch (in) O.C. Bracing Non-Composite Limiting Height (L/240) at 10 Pounds Per Square Foot (PSF) Pressure and 12 Inch (in) Spacing

 N/A 11 ft 8 in.

48 Inch (in) O.C. Bracing Non-Composite Limiting Height (L/360) at 10 Pounds Per Square Foot (PSF) Pressure and 12 Inch (in) Spacing

 N/A 10 ft 2 in.

48 Inch (in) O.C. Bracing Non-Composite Limiting Height (L/120) at 5 Pounds Per Square Foot (PSF) Pressure and 16 Inch (in) Spacing

 N/A 14 ft 7 in.

48 Inch (in) O.C. Bracing Non-Composite Limiting Height (L/240) at 5 Pounds Per Square Foot (PSF) Pressure and 16 Inch (in) Spacing

 N/A 11 ft 10 in.

48 Inch (in) O.C. Bracing Non-Composite Limiting Height (L/360) at 5 Pounds Per Square Foot (PSF) Pressure and 16 Inch (in) Spacing

 N/A 10 ft 4 in.

48 Inch (in) O.C. Bracing Non-Composite Limiting Height (L/120) at 7.5 Pounds Per Square Foot (PSF) Pressure and 16 Inch (in) Spacing

 N/A 11 ft 11 in.

48 Inch (in) O.C. Bracing Non-Composite Limiting Height (L/240) at 7.5 Pounds Per Square Foot (PSF) Pressure and 16 Inch (in) Spacing

 N/A 11 ft 8 in.

48 Inch (in) O.C. Bracing Non-Composite Limiting Height (L/360) at 7.5 Pounds Per Square Foot (PSF) Pressure and 16 Inch (in) Spacing

 N/A 10 ft 2 in.

48 Inch (in) O.C. Bracing Non-Composite Limiting Height (L/120) at 10 Pounds Per Square Foot (PSF) Pressure and 16 Inch (in) Spacing

 N/A 10 ft 4 in.

48 Inch (in) O.C. Bracing Non-Composite Limiting Height (L/240) at 10 Pounds Per Square Foot (PSF) Pressure and 16 Inch (in) Spacing

 N/A 10 ft 4 in.

48 Inch (in) O.C. Bracing Non-Composite Limiting Height (L/360) at 10 Pounds Per Square Foot (PSF) Pressure and 16 Inch (in) Spacing

 N/A 9 ft 3 in.

48 Inch (in) O.C. Bracing Non-Composite Limiting Height (L/120) at 5 Pounds Per Square Foot (PSF) Pressure and 24 Inch (in) Spacing

 N/A 11 ft 11 in.

48 Inch (in) O.C. Bracing Non-Composite Limiting Height (L/240) at 5 Pounds Per Square Foot (PSF) Pressure and 24 Inch (in) Spacing

 N/A 10 ft 4 in.

48 Inch (in) O.C. Bracing Non-Composite Limiting Height (L/360) at 5 Pounds Per Square Foot (PSF) Pressure and 24 Inch (in) Spacing

 N/A 9 ft 1 in.

48 Inch (in) O.C. Bracing Non-Composite Limiting Height (L/120) at 7.5 Pounds Per Square Foot (PSF) Pressure and 24 Inch (in) Spacing

 N/A 9 ft 9 in.

48 Inch (in) O.C. Bracing Non-Composite Limiting Height (L/240) at 7.5 Pounds Per Square Foot (PSF) Pressure and 24 Inch (in) Spacing

 N/A 9 ft 9 in.

48 Inch (in) O.C. Bracing Non-Composite Limiting Height (L/360) at 7.5 Pounds Per Square Foot (PSF) Pressure and 24 Inch (in) Spacing

 N/A 8 ft 11 in.

48 Inch (in) O.C. Bracing Non-Composite Limiting Height (L/120) at 10 Pounds Per Square Foot (PSF) Pressure and 24 Inch (in) Spacing

 N/A 8 ft 5 in.

48 Inch (in) O.C. Bracing Non-Composite Limiting Height (L/240) at 10 Pounds Per Square Foot (PSF) Pressure and 24 Inch (in) Spacing

 N/A 8 ft 5 in.

48 Inch (in) O.C. Bracing Non-Composite Limiting Height (L/360) at 10 Pounds Per Square Foot (PSF) Pressure and 24 Inch (in) Spacing

 N/A 8 ft 1 in.

Notes for 48 Inch (in) O.C. Bracing Non-Composite Limiting Height

 N/A
  • Heights are based on AISI S100-07 with S2-10 Supplement, and AISI S100-12 Specification using steel properties alone.
  • Above listed Non-Composite Limiting Heights are applicable when the unbraced length is less than or equal to (Lu) as listed in section properties.
  • End bearing must be 1 inch.
  • The minimum overlap of the TSO (Outer Stud) and TSE (Inner Stud) must be 8 inches and the maximum un-lapped length of the TSE must be 4 inches.

Compliance

Compliance

 N/A TRAKLOC®’s ICC-ES Report # ESR-1464 is in compliance with:
  • 2015 and 2012 International Building Code® (IBC)
  • 2016 California Building Code (CBC)
  • 22017 Florida Building Code (FBC)

United States (U.S.) and Foreign Patents

United States (U.S.) and Foreign Patents

 N/A The TRAKLOC® product line provided by ClarkDietrich® Building Systems is licensed under the following U.S. and Foreign Patents:

U.S. Patent No. 7,223,043
U.S. Patent No. 7,594,311
U.S. Patent No. 8,061,099
U.S. Patent No. 8,074,416
Japan Patent No. 4934868
Japan Patent No. 5156889
Australia Patent No. 2006201344
Australia Patent No. 2005332657

TRAKLOC® Track

TRAKLOC® Track

 N/A TRAKLOC® track has two unique features. The most obvious feature of the TRAKLOC® track is the V-groove rolled into the flanges of the track to match the swaged ends of the TRAKLOC® stud. Next, are the dimples pressed into the center of the web. Together, the V-groove and the dimples provide a positive connection between stud and track without the need for mechanical fasteners.

TRAKLOC® track standard length is 10'-0". Shorter lengths are available for non-standard conditions.

Storage Requirements

Storage Requirements

 N/A TRAKLOC® is a dynamic system consisting of two moving parts. To maintain the telescoping feature of this system, it is important to store TRAKLOC® studs indoors, free of excessive dust and airborne particulates.

Head-of-Wall Deflection Required?

Head-of-Wall Deflection Required ?

 N/A Elevator Studs are not for deflection by themselves. However, deflection can be achieved by using MaxTrak® slotted deflection track or deep leg track with lateral bracing at the head of the wall.

Other Benefits Include

Other Benefits Include

 N/A
  • Significant productivity gains. Adjustable length studs accommodate variances in the deck height without the need to measure or cut studs on the jobsite.
  • Increased safety. Less measuring and cutting results in less trips up and down ladders or scaffolds and reduced use of chop saws.
  • Noise reduction and cleaner jobsite. Eliminating chop saw use allows work to continue during the day in occupied buildings and may reduce requirement for after-hours fire watch. Less cutting results in less scrap and cleaner safer jobsite.

Features and Benefits

Features and Benefits

 N/A
  • Available in 18mil (25ga) 33ksi, 24mil (20EQ) 57ksi, 30mil (20ga DW) 33ksi and 33mil (20ga) 33ksi.
  • Available in 2-1/2", 3-5/8", 4" and 6".
  • For use in non-load-bearing interior walls.
  • Twists and locks into place. Studs can be installed from the ground, greatly reducing time spent climbing ladders and scaffolding.
  • Installation of TRAKLOC® is ICC-ES approved without the use of fasteners to attach the studs to the top or bottom track. ICC-ES Report # ESR-1464.
  • Significant productivity gains are possible versus conventional stud and track framing. This results in substantial installed cost savings!
  • Safer Framing System™ reduces jobsite hazards. Less time spent climbing scaffolds, ladders, lifts and bending over to install screws results in fewer job related injuries and reduced workers’ compensation costs. Less cutting of studs with noisy chop saws.
  • Allows for seismic and live-load vertical interfloor deflection in the stud, not the track. This feature eliminates the need for deflection tracks in fire-rated head-of-wall assemblies.

Addition Information

Addition Information

 N/A TRAKLOC® stud without telescopic extension. Studs are fixed length and not adjustable and have a TRAKLOC® swaged end on both ends of the stud allowing the stud to be connected to the top and bottom track without fasteners.
  • Connected without the use of fasteners
  • Ideal for partition walls that do not go from deck to deck and non-composite "above-grid" wall assemblies that have suspended ceilings, as well as TI (tenant improvement) and remodel applications
  • Less time on lifts/ladders
TRAKLOC® non-load bearing interior wall system is Intertek Warnock Hersey Design Listed and approved for use in both one and two-hour fire-rated head-of-wall assemblies requiring deflection in accordance with ASTM E119 and ASTM E1966. Intertek Design Listings Nos. on inside back cover.

Note

Note

 N/A For SI Units: 1 inch = 25.4 mm, 1 lb = 4.45 N, 1 ksi = 6.89 N/mm².
  • Calculated properties are based on AISI S100-07 with S2-10 Supplement and AISI S100-12, North American Specification for Design of Cold-Formed Steel Structural Members.
  • Gross and torsional properties are based on full-unreduced cross section of the studs, away from punch-outs.
  • For deflection calculations, use the effective moment of inertia.
  • TSE (Inner Stud) must be 8 inches and the maximum un-lapped length of the TSE must be 4 inches.
  • 1 Stud/Track End Reaction (Rx) is the maximum end reaction (web crippling) capacity based on a minimum bearing length of 1 inch.
  • 2 The allowable moment based on local buckling (Mal) is based on the compression flange continuously braced.
  • 3 The distortional buckling moment (Mad) does not consider the beneficial effect of sheathing to rotational stiffness, Kɸ = 0.