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<br /> DESIGN VALUES
<br /> Design Values for MEL, MSR, and Microllam® LVL
<br /> (Values based on 2x4 nominal cross section)
<br /> - --- -------MEL . .--------MSR --_ ----------
<br /> —
<br /> Properties Southern Pine Spruce-pine-fir Douglas Fir-Larch Southern Pine a LVL
<br /> (SP) (SPF)i'i (North)(MN) (SPp2) cuss Chord Grad
<br /> M-12 ' M-23 1650f-1.5E i 2100f-1.8E • 18001 1 6E 24001-211E
<br /> Flexural I
<br /> Stress Fb = 1,600 psi ' 2,400 psi 1,650 psi 2100 psi 1,800 psi 2,400 psi
<br /> Tension Stress Ft = 850 psi 1,900 psi 1020 si 1 1,1755 psi 176 gx6l
<br /> -575 psi psi 1,92
<br /> ,-
<br /> Compression Perpendicular to Grain Fbi = 565 psi I 805 psi 425 psi") 1 525 psi ; 625 psi 805 psim 75D psi
<br /> Compression Parallel to Grain F,b = 1,675 psi! 1,975 si 1,700 psi I1,875 psi I 1,750 psi 1,975 psi 2,635m psi
<br /> Horizontal Shear Parallel to Grain F, = 175 psi 190 psi 135 psi•w i 160 psi _ 180 psi 190 psim 285 psi
<br /> Modulus of Elasticity E = 1.6 x 106 psi I 1.8 x 106_psi 1.5 x 106 si j 1.8 x 106 psi 1.6 x 106 psi . 2.0 x 106 si 2.0 x 106 psi
<br /> Adjusted Modulus of Elasticity E■;,, = 750,000 psi i840,000_psi-_ 760,000 psi I 910,000 psi 810,000 psi_ ; 1,020,000psi 1,016,535 psi
<br /> (1)If product species is stamped SP,Compression perpendicular to grain(F,,i)is 565 psi and Horizontal shear parallel to grain(F,)is 175 psi.
<br /> (2)If product species is stamped DFLN,Compression perpendicular to grain(Fu)is 715 psi and Horizontal shear parallel to grain(F,)is 180 psi.
<br /> (3)For 2x4.For 2x6,Fb=3,060 psi.For 2x8,Fb=2,945 psi.For other depths,multiply Fb=2,750 psi by da1urss
<br /> (4)Values for 2x6 and 2x8 are the same as 2x4.
<br /> (5)Fr has been adjusted for length effects in accordance with MUM.
<br /> Using Microllam LVL in Truss Chord Applications
<br /> Only Microllam®LVL that is stamped 2.0E-2750 Fa or 2925 Ft,and"ICC-ES ER-1387"is suitable for use in plated trusses.This special grade of
<br /> Microllam LVL must be used in accordance with truss design software,using truss plate values supplied by the truss plate manufacturer.
<br /> The purchaser is solely responsible for proper design,fabrication,shipping,and for providing installation and bracing instructions for the finished truss.
<br /> APPROVED APPLICATIONS SPECIAL CONSIDERATIONS
<br /> Do General Information
<br /> Weyerhaeuser truss chord products are recommended for the following truss All truss design and fabrication should follow provisions in the National Design Standard
<br /> applications: for Metal Plate Connected Wood Truss Construction.A commitment to a quality assurance
<br /> ■ Flat bottom chord girder and common trusses program is a must.The role of a quality assurance program is to"assure and document"
<br /> that key elements of the end product are manufactured to pre-determined minimum
<br /> • Attic trusses requirements.Weyerhaeuser recommends the quality assurance provisions in ANSI/TPI
<br /> • Tail-bearing(tray)trusses National Design Standard For Metal Plate Connected Wood Truss Construction.
<br /> • Scissor trusses There are unique aspects regarding the handling and installation of metal-plate-connected
<br /> • Parallel topand bottom chord,includingtrusses.The Structural Building Components Association's(SBCA)Building Component
<br /> girder trusses Safety Information(BCSI)summary sheets provide a wealth of information on truss issues,
<br /> • Mono-pitched trusses including:
<br /> • Trusses over 60'in length. • Best practices for truss installation
<br /> • Long span applications
<br /> DO NOT •Temporary bracing during construction
<br /> Weyerhaeuser truss chord products should not be used in truss applications • Fall protection
<br /> with the following highly irregular chord features: • Proper storage and handling
<br /> I
<br /> DO NOT use in trusses with bottom or top Environmental Conditions
<br /> chords that contain more than three ,', Microllame LVL must be protected from the weather.Frequent or prolonged exposure to
<br /> different sloping sections. L``oo o,I moisture or sunlight will reduce the service life of the product.
<br /> Avoid environments where steam or caustic chemicals may come in contact with the
<br /> trusses,including environments such as commercial laundries,food-processing facilities,
<br /> indoor swimming facilities,and recycling plants.
<br /> OD NOT use in trusses with bottom or top chords that contain a re-entrant angle ,� ..
<br /> greater than 45°(fillers do not count). -
<br /> L re-entrant angle
<br /> v,
<br /> DO NOT plate into narrow edges of
<br /> Microllam LW as is commonly done t'��*0
<br /> in 4x2 fiat-chord truss systems. mIW AW
<br /> Weyerhaeuser Truss Chord Specifiers Guide 9008 I June 2019 •
<br /> 3 2-3a\2
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