Steps to model / analyse and design strap beam :
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Design a trap beam for 2-footings for 2 columns : - col(1) -
(60*30) - EXterior column working reaction = 124 ton. - col(2) -
(90*30) - Interior column working reaction = 186 ton. - B.C = 2
kg/cm2 = 20 t/m2. - Fcu = 25 Mpa = 250 kg/cm2. - Distance between
column centers = 6 m. 1-Modelling - with the approximate method , k
(spring) = (100-120)*B.C=100*20=2000 t/m3 - Define the grids to
easily draw the footings and define the loads . - Define new
thickness of the footings with depth = 60cm.But , don't forget to
define parameters of foundation elasticity with Kz = 2000 t/m3. -
Assume the beam section = 50cm * 90cm - Define node load at the
column centers 124 & 186 tons . - From geometry >> add.
attributes >> ber elastic ground - Add new elastic ground
with Kz = 2000 t/m2 . 2-Make analysis and see you results . . See
this AlbumETABS 2015 Steel ahmeed al-lahham
