Building 3 – Advanced Structures
Homework 5
Due: Wednesday, 4/14/21
Technical Assignment 4 – Steel Design
XXXXXXXXXXD (10.3.B provided for reference)…
See Example 3, Section 10.2, but assume A992 steel and compute Fcr
y the equations in AISC-360 Section E3.
2. Suggestion: select a section using Table 3-6 from the AISC Manual,
then check it explicitly for flexural capacity using the equations in
AISC-360, Section F2. Compute the DCR once you select a shape.
3. Use the provisions of AISC-360, Section G2.
4. The Ordinary Concentric Braced Frame shown below is used to resist
wind loads in a multistory building as well as gravity loads for economy.
The wind loads (W) due to wind pressures in this story and from the
column shear above are computed to be 60 kips at story level (aligned
with CL of beam). Gravity loads from the stories above are 220 kips
dead load (D) and 140 kips live load (L) to each column as well as 3 kips
per lineal foot uniform distributed load due to dead load and 1.5 kips
per lineal foot uniform distributed load from live load acting on the
eam. Conservatively, assume pinned connections everywhere and
that the
aces provide no resistance to gravity loads. Do a preliminary
sizing on the beam, columns and
aces assuming a) a
ace with
sufficient buckling strength to develop equal forces between both
aces and b) a slender
ace such that the compression strength can
e ignored. For case (b) check that the beam can support the
additional vertical load. No need to do beam-column checks on the
columns. The primary framing elements are to be W sections, but the
ace shape is left to your discretion. Typical sections most often used
for this purpose are angles (L), double angles (2L), and HSS. Utilize the
AISC Manual tables as necessary and remember to factor your
demands.