Civil Engineering Reference
In-Depth Information
To accommodate the plain strain limitations of the finite element model, the
cross sectional properties of the structural elements were determined by dividing
the column and beam properties by the tributary width of the frame selected as 10
feet, and by utilizing the equivalent area and moment of inertia per foot of length
of the floor slab. Given that gravity loads on the structural elements are not of
concern, this method of resolving the cross sectional properties of the rigid frame
elements allows an acceptable modeling of the lateral stiffness of the rigid frame
under plane strain conditions.
Table 7.1
Finite Element Analysis Parameters
Parameter
Variation
Number of Bays for Structural Frames, n
1, 3, 6, 10, 15 and 20
Bay Lengths for Structural Frames, L
b
(ft)
10 and 20
Number of Stories for Structural Frames, s
1 thru 5
Story Height, h (ft)
10
Structural Beam Properties
Cross Sectional Area, A
b
(in
2
)
144
Moment of Inertia, I
b
(in
4
)
2073 and 1036
Structural Columns Properties
Cross Sectional Area, A
c
(in
2
)
144 and 432
Moment of Inertia, I
c
(in
4
)
2073 and 41460
Structural Wall Properties
Cross Sectional Area, A
w
(in
2
/ft)
144
Moment of Inertia, I
w
(in
4
/ft)
2073
Modulus of Elasticity of Structural Members, E
s
(ksi)
3150
Poisson Ratio of Structural Members,
ν
s
0.25
Density of Structural Members,
γ
s
(pcf)
150
Backfill Soil Properties
Internal Friction Angle,
φ
(Degrees)
30 and 40
Dilatancy Angle, ψ (Degrees)
0 and 10
Cohesion, c (psi)
0
Modulus of Elasticity, E (ksi)
41500 and 144000
Density, γ (pcf)
100 and 120
Strength Reduction for Interfaces
0.75
