scherry
Structural
- Mar 20, 2003
- 54
NDS spec for wood construction, 2001. Section 3.3.3: 3.3.3.1, 3.3.3.2, 3.3.3.3 all give conditions where the factor CsubL can be considered to be 1.0, but if I look at section 4.4.1 it gives me some other conditions, which if satified give CsubL = 1.0. the question is if I look at 4.4.1.2 para c, isn't it in conflict with 3.3.3.3? That section seems to say that all bending members with ends blocked against rotation or lateral displacement with sheathing on the compression edge are fine with CsubL=1.0 but para c seems to say that this is not true for 2x10 and deeper (and 3x16). I have never used a 3x16 solid sawn, but I have used or seen used 2x10, 2x12, 2x14, the occasional 2x16 in older buildings. The older buildings had blocking and bridging in many cases, but did not in some cases have continuous sheathing, or had straight sheathing. Of course I realize that if I have negative moment that the compression edge is not likely to be supported throughout its length, but that is probably a different issue altogether. Thanks.
