CMU allowable unbraced heights
CMU allowable unbraced heights
(OP)
I have a 30' tall unbraced interior load-bearing wall (not a shear wall, just picking up .2klf DL + .2klf LL roof loads, in Seismic Cat 'A'). Per Enercalc design, can use 8" CMU w/ #5 @ 32" o.c. But I see in ACI 530 Table 5.5.1 that max allowable height/thickness ratio = 18. To meet this criteria would mean that I couldn't even use 12" CMU here.
Similarly, I have a 24' tall exterior load-bearing shear wall on same project - still not very heavily loaded & I can easily reinforce it to meet allowable capacity requirements. But 12" CMU wouldn't meet the above h/t ratio here either.
Are there any exceptions to this h/t ratio criteria?
Similarly, I have a 24' tall exterior load-bearing shear wall on same project - still not very heavily loaded & I can easily reinforce it to meet allowable capacity requirements. But 12" CMU wouldn't meet the above h/t ratio here either.
Are there any exceptions to this h/t ratio criteria?






RE: CMU allowable unbraced heights
RE: CMU allowable unbraced heights
So if such were the practices of old, it is quite unlikely that more modern codes, that have added to the lack of confidence in masonries, even when reinforced, may be more lenient on slenderness/stability issues.
For these cases where some degree of slenderness is wanted an embedded steel structure may be the solution.
RE: CMU allowable unbraced heights
RE: CMU allowable unbraced heights
RE: CMU allowable unbraced heights
RE: CMU allowable unbraced heights