The Portal Frame - The Analysis of Irregular Shaped Structures - page 481

The steel shear walls consist of 10 gauge steel sheets bent in a corrugated pattern
for the vertical sheathing. Wood studs or cold-formed steel members are attached to
the ends of the walls, which are used to provide a nailing surface for finish material
and to help integrate with the other framing members. The wood walls consist of
oriented strand board (OSB) sheathing applied over wood studs. The edges of the
sheathing are typically reinforced with nailed steel strapping. The wall panels come
with preinstalled hold-down anchors. The wall panels can also be used at garage door
openings, where the installation includes the connection to a header similar to the
APA portal frame. Both wall systems are required to be installed on a rigid concrete
foundation.
The Strong-Frame is a steel ordinary moment-resisting frame that is designed in
accordance with
• 2006InternationalBuildingCode
• ASCE7-05, Minimum Design Loads for Buildings and Other Structures
• AISC360-05, Specification for Structural Steel Buildings
• AISC341-05, Seismic Provisions
• 2004RCSC Specifications for Structural Joints Using ASTM A325 or A490 Bolts
• ACI318-05,BuildingCodeRequirementsforStructuralConcrete,AppendixD
The moment frames are also required to be installed on a rigid concrete foundation.
General guidelines for the foundation are provided by the manufacturer, which are
based only on the foundation size required to develop the full capacity of the anchors.
The foundation design should be similar to Fig. 13.10.
Strong-Wall panels and Strong-Frames can be used for wall bracing in accordance
with IRC Section R602.10 or the conventional wood light-framed construction in
Section 2308 of the IBC. The Strong-Wall panels are permitted to replace braced wall
panels or alternate braced wall panels on a one-to-one basis. In some cases, one
Strong-Wall panel is permitted to replace two braced panels, or two Strong-Wall pan-
els can replace three braced panels. As with any system or component discussed in
this topic, the engineer is responsible for establishing a complete load path. The engi-
neer or designer is also responsible for ensuring compliance with all the manufac-
turer's requirements and all applicable codes and standards, and for providing the
necessary information on the construction documents. Typically, the engineer or
designer will research the manufacturers' specific requirements to do the analysis,
but to ensure that it is built per the design, the contractor and building inspector
need to have the information included in the construction documents. Failure to do
so could cause a failure of the system.
An additional method of designing wood moment-resisting framed walls is pre-
sented in Chap. 14. The method of analysis requires rigorous analysis, special detailing,
and fabrication.
Problem 13.1: One- and Two-Story Portal Frame Analysis
Given: A plan for a garage is shown having a plan dimension of 24′ × 24′. The pier width
for the one-story and second-floor piers is 16″. The pier width for the first-floor piers of
a two-story is 24″. See Fig. P13.1.