huangyhg

request for explanation for load combination for anchor bolt
hi friends,
i am designing anchor bolt for tank using strength design method (asce7-05). as i understand we need to use to eq. 5 and 7 to get tension on ab, i.e.
(1.2+0.2sds)*d+ over strength factor*qe eq 5
(0.9-0.2sds)*d+ over strength factor*qe eq 7
in eq 5 :
1.2 and 0.2sds will be in same direction as d and opposite to earthquake forces in horizontal direction to get tension on anchor bolt
in eq 7:
(0.9-0.2sds)*d will be opposite to earthquake forces in horizontal direction to get
tension in anchor bolt

i am getting confused with different directions. i will appreciate if somebody can explain me the directions.
thanks for the help

__________________
借用达朗贝尔的名言：前进吧，你会得到信心!
[url="http://www.dimcax.com"]几何尺寸与公差标准[/url]