wood wall stud

huangyhg

wood wall stud
normally we have plywood sheeting on both sides of wall studs in a typical house. so for bending we can take beam stability factor cl =1
yes... for typical wall studs i would use cl=1.0 because the sheathing restrains lateral buckling. gypsum board works too.  
what about cp(for axial capacity of stud). we cannot take it = 1 right?. we can only use minimum slenderness ratio and not the larger slender ness rayioon in our calcs for fcce or f'c.
you can take cp=1.0 for weak axis buckling (for a stud wall), but not for strong-axis buckling.   
cp is usually the controlling modification factor for wood stud walls; it will typically be significantly smaller than 1.0. if it's approaching 1.0, you may want to consider increasing the economy of your design by using a smaller column (stud) section.
since you are looking at bending of a stud wall, make sure to check the "bending and axial compression" interaction equation (1995 nds section 3.9.2).
but, cp=1.0 for weak-axis buckling.  don't use l/d for weak-axis in the column stability equation.  also, when doing the combined check, make sure to use the correct fce (in the plane of buckling being considered - for your case it will be about the strong axis).