3RD YEAR CONSTRUCTION FINAL EXAM

Wind and seismic loads are static loads

Building mass is beneficial for resisting wind load

Building mass is beneficial for resisting seismic load

Stiffness is beneficial for resisting seismic loads

Ductility is beneficial for resisting seismic loads

A site specific concern for wind load is exposure class

A site specific consideration for seismic load is exposure class

Wind force is linearly proportional to wind speed

The downwind face of a building typically experiences an outward suction force

Building projections such as balconies and parapets are typically subject to lower wind forces per square foot than the rest of the building exterior

Wind vortices can cause a tall building to oscillate

Designing a building so that its natural period of oscillation is the same as the soil it bears on is an effective approach to resisting seismic forces

Cantilevered balconies and similar projections are often damaged by the vertical ground accelerations that occur during an earthquake

Building codes require that high occupancy buildings (eg. sports arenas) are designed with a greater factor of safety for wind and seismic loads than buildings with low occupancy (eg. warehouses)

Shear walls must extend laterally over almost every bad to be effective

Moment frames must extend over almost every bay to be effective

A flexible diaphragm is more effective than a rigid diaphragm at distributing lateral forces within a building structure

A diagrid structure would not be effective for resisting lateral forces

A house with light timber framing (2x6 studs) typically requires masonry shear walls (brick, CMU, or concrete) to effectively resist lateral forces

In multi-story buildings the cores containing vertical circulation elements (stairs and elevators) typically play no role in resisting vertical or lateral loads

Vertical continuity is essential for shear walls

A building in a seismic zone needs re-entrant corners to effectively resist lateral forces

In a multi-story building it is preferable for a vertical member (columns) to fail before horizontal members (beams) fail

Plan regularity is an important consideration in designing structure to resist lateral forces

Story drift under lateral laods contributes to the overturning moment on a structure

In a high-rise structure, columns typically have the same load capacity at the bottom levels as at the top levels

It is possible to suspend the floors of a building from trusses at roof level using tension members

Shear and over turning moment due to lateral forces are maximum at the bae of high-rise building

The worlds tallest building rely primarily on moment-resisting frames to resist lateral forces

The behavior of a slender tower subject to lateral forces is analogous to a cantilever beam

Slenderness is not a concern for high-rise structure; the more slender the better

A circular structural layout can be beneficial for buildings with a tensile roof structure

A concrete plate requires a more regular column grid than a beam structure

Two-way spanning systems require a nearly square bay to be effective

If columns do not align from one floor to the next, a transfer structure is needed

Long span roof-systems typically rely on flexure to carry loads

In a multi-story building it is simpler to integrate a large span space at the lower levels, with smaller bays above it, than to locate a large span space at the top level with smaller bays below it

Flexure is more efficient structural mechanism than axial forces to resist loads

Folding is a means of increasing the depth of a structure in order to increase its flexural capacity

Shell structures can be relatively thin because they rely on flexural strength to resist loads

Domes typically have anti-clastic curvature

A hyperboloid is a ruled surface

Footings are subject to bending and shear forces

Soil pressure on a retaining wall decreases with depth

Strip footings are typically used to support columns

With a floating foundation the building displaces a volume of earth equal to the weight of the building so the building effectively floats in the soil

Truss members resist loads primarily through flexure

Increasing the span of a beam has little effect on the deflection of the beam

Buckling is a concern for members in compression

Inclining a column (away from vertical) can increase its ability to resist lateral forces

Fire is not a concern for a building with a steel structure

Tilt-up concrete is typically used for high-rise structures

Quality control is typically higher for pre-cast concrete elements than for site-cast concrete elements

Concrete typically undergoes a large deformation before failure

Material consistency and quality is more frequently a problem for steel than for solid sawn lumber

Glulam beams are limited for 24' in length

Heavy timber framing is more fire-resistant than light timber-framing

Concrete, an isotropic material, is equally strong in tension and compression