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<br /> DESIGN VALUES
<br /> Design Values for MEL, MSR, and Microflame LVL
<br /> (Values based on 2x4 nominal cross section)
<br /> MEL MSR
<br /> Properties Southern Pine Spruce-pine-fir Douglas Fir-Larch Southern Pine _Microllam®lvl
<br /> (SP) (SPF)r'i (North)(DFLN) (SP)Y�) (toss Chord Grad-0?
<br /> M-12 M-23 1650f-1.5E 2100f-1.8E 1800f-1.6E 2400f-2.0E -
<br /> Flexural Stress F, = 1,600 psi 2,400 psi 1,650 psi 2,100 psi 1,800 psi 2,400 psi 250f3) i
<br /> >Tension Stress Ft = 850 psi 1,900 psi 1,020 psi 1,575 psi 1,175 psi 1,925 psi (760r4115r psi
<br /> Compression Perpendicular to Grain Fri = 565 psi 805 psi 425 psiiii 525 psi 625 psi 805 psi(2) 750 psi
<br /> Compression Parallel to Grain Frei = 1,675 psi 1,975 psi 1,700 psi 1,875 psi 1,750 psi 1,975 psi 2,635(4)psi
<br /> Horizontal Shear Parallel to Grain F, = 175 psi 190 psi 135 psi") 160 psi 180 psi 190 psii�1 285 psi
<br /> Modulus of Elasticity E = 1.6 x 106 psi 1.8 x 106 psi 1.5 x 106 psi 1.8 x 106 psi 1.6 x 106 psi 2.0 x 106 psi 2.0 x 106 psi
<br /> Adjusted Modulus of Elasticity Em,, = 750,000 psi 840.000 psi 760,000 psi 910,000 psi 8I0,000 psi 1,020,000 psi 1,016,535 psi
<br /> (I)If product species is stamped SP,Compression perpendicular to grain(Fa)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(Frl)is 715 psi and Horizontal shear parallel to grain(F,)is 180 psi.
<br /> (3)For 2x4.For 2x6,F,=3,060 psi.For 2x8,Fb=2,945 psi.For other depths,multiply Fb=2,750 psi by[r2].aise
<br /> a
<br /> (4)Values for 2x6 and 2x8 are the same as 2x4.
<br /> (5)F,has been adjusted for length effects in accordance with ANSI/TPI.
<br /> Using Microllam®LVL in Truss Chord Applications
<br /> Only Microllam LVL that is stamped 2.0E-2750 Fb er 2925 Fb and"ICC-ES ER•1387"is suitable for use in plated trusses. This special grade of
<br /> Microllame LVL must be used in accordance with truss design software,using truss plate values supplied try 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 ANSITIPI
<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(SCSI)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 /> fiu NOT x� 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 /> DO NOT use in trusses with bottom or top is
<br /> \\ Environmental Conditions
<br /> chords that contain more than three Microllam®LVL must be protected from the weather.Frequent or prolonged exposure to
<br /> different sloping sections. 0 o . / 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 /> 00 NOT use in trusses with bottom or top e
<br /> chords that contain a re-entrant angle ' 41
<br /> greater than 45°(fillers do not count),
<br /> re-entrant angle •
<br /> DO NOT plate into narrow edges of
<br /> Microllam®LVL as is commonly done
<br /> in 4x2 flat-chord truss systems. `;
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<br /> Weyerhaeuser Truss Chord,Specifier's Guide 9008 I June 2019 3 ' t�
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