March 25 2015 25 points A building is to be framed as shown

March 25, 2015 (25 points) A building is to be framed as shown, with the pinned support at the botton of each column. A tables, if the factored design load, Pu 920 kips, select the most economical W12 member for column A1. Perform all necessary checks. Column and bearm orientations are shown. 4. beams and girders are W18x86 (A992). Using the AISC All Horizoatal Members W18s86 (A 992) COLUMN ORIENTATION

Solution

unbraced length of column A1 about minor axis= 118-100=18 ft

unbraced length of column A1 about major axis=134-100=34 ft

design load = 920 kips

from minor axis orientation,the most economical W12 section is W12x106 which has a capacity of 987 kips

from major axis orienattion point of view, the most economical section is W12x106 which has a capacity of 948 kips

Therefore, the most economical section is W12x106