1 September 1999
2-3. BUILDING SYSTEM USE IN MILITARY CONSTRUCTION. Various bearing wall systems,
building frame systems, and moment resisting frame systems were described in the preceding
paragraph. It should be noted that a particular building type (such as Type 9) might be either
a bearing wall system or a building frame system. Descriptions of systems commonly used in
military construction, and discussions of particular systems that should be avoided, are
presented in the following paragraphs.
a. Bearing Wall Systems. A bearing wall system is a structural system without a
complete vertical load carrying space frame. Bearing walls or bracing systems support gravity
loads. Shear walls or braced frames resist lateral loads. Bearing wall systems of reinforced
concrete and reinforced masonry (Types 9, 11, 12, 13, and 14) are common to all types of
military construction. Bearing wall systems of steel construction (Types 4 and 6) are also
b. Building Frame Systems. A building frame system is a structural system with an
essentially complete space frame that supports gravity loads. Shear walls or braced frames
resist lateral loads. Building frame systems in which non-load bearing shear walls or braced
frames resist lateral loads (Types 4, 6, 9, 11, and 12 buildings) are excellent systems for high
seismic regions and are commonly used in military construction.
c. Moment Frame Systems. A moment resisting frame system is a structural system with
an essentially complete space frame that supports gravity loads and resists lateral wind and
earthquake forces. Moment resisting frame systems of steel and concrete (Types 3, and 8
buildings) are sometimes used. Moment frames are recommended in cases where it is
undesirable to restrict the interior of the building with interior bracing or shear walls. Interstory
drift is a problem with moment frame construction and the interaction of the moment frames
with architectural and other nonstructural building elements must be considered.
d. Other Systems. Because of fire protection concerns, systems of wood construction
(Type 1 and Type 2 buildings) are generally limited to residential construction. Although, in the
western United States it is not uncommon to find wood construction used for the construction
of one and two story office buildings, school buildings, and commercial buildings. Steel light
frame (Type 5) buildings are often used for industrial type buildings, and for one and two story
dormitory construction. Infill systems (Type 7, and 8 buildings) although commonly used in
older construction, are not recommended for new military buildings because of undesirable
interaction that occurs between the infill walls and the frames when the building is subjected to
lateral loads. Infill wall systems are particularly undesirable in high seismic regions.
2-4. CHARACTERISTICS IMPORTANT TO BUILDING PERFORMANCE. (Adapted from DOE
"Design and Evaluation Guidelines for Department of Energy Facilities Subjected to Natural
Phenomena Hazards") Proper design and detailing of structural systems and their connections
is critical. Structural engineers should work closely with the building architect in the early
phases of building design to assure characteristics important to building performance such as
structural system configuration, load path continuity, redundancy, ductility, and the quality of
materials and construction, become a integral part of the concept design.
a. System Configuration. The configuration of the structural system is important.
Irregularly configured structures under extreme loading conditions, especially earthquake