EXAC - Section 3 - Final Project
What is: Design wind pressure? - answer Design wind pressure:
Minimum design value for the equivalent static pressure on the exterior surfaces
resulting from critical wind velocity (equal to a reference wind wind pressure measured
at 33', 10m). The # is modified by a bunch of coefficients to account for: exposure
conditions, building height, wind gusts, geometry/orientation.
Why are horizontal forces more critical than vertical ones in seismic design? - answer
Because structures usually have considerable reserve for dealing with additional vertical
loads.
Define Base Shear. - answer Base shear:
Minimum design value for the total lateral seismic force (assumed to act in any
horizontal direction)
Define the following: Collinear Forces, Concurrent Forces, Nonconcurrent Forces. -
answer Collinear Forces:
Occur along straight line. Vector sum= sum of magnitude of forces acting along same
line of action.
Concurrent Forces:
Lines of action intersecting at common point. Vector sum=equivalent to, and produces
same effect on rigid body as the application of the vectors of the several forces.
Nonconcurrent Forces:
Lines of action that do not intersect at common point. Vector sum=single force that
would cause the same translation and rotation of a body as the set of original forces.
What is a moment (structural forces)? - answerMoment:
The tendency of a force to produce rotation of a body about a point or line
What is a Couple (structural forces)? - answerCouple:
Force system of 2 equal parallel forces acting in opposite directions tending to produce
rotation but not translation
What are beams designed to do? - answerDesigned to carry and transfer transverse
loads across to supporting elements.
Define Deflection - answerDeflection:
perp distance a spanning member deviates from true course under transverse loading
,What is the difference between a simple beam and a Fixed-End Beam? - answerSimple
Beam:
Rests on supports at both ends - no moment resistance (ends free to rotate)
Fixed-end beam:
Both ends fixed against translation and rotation (reduced max deflection, transferred
bending stresses, increased rigidity)
Distinguish between the following three frame types:
-Fixed Frame
-Hinged Frame
-Three Hinged Frame - answerFixed Frame
rigid frame connected to its supports with fixed joints (more resistant to deflection than
hinged from but also more sensitive to settlements and thermal expansion/contraction)
Hinged Frame -
Rigid frame connected to its joints with pinned connections (pinned connections prevent
high bending stresses by allowing rotation)
Three-hinged Frame - structural assembly of 2 rigid sections connected to each other
and to its supports with pin joints (more sensitive to deflection than fixed or hinged, 3-
hinged system is least affected by support settlements and thermal stresses - can also
be analyzed as a statically determinate structure
Name 1 kind of beam for each wood, steel, and concrete, that can span >60' (18m). -
answerWood:
Laminated Beams (Timber)
Trusses (Timber)
Steel:
OWSJ
Concrete:
Precast Tees
List three basic mechanisms for resisting lateral loads. - answerRigid Frame
steel or reinforced concrete with rigid joints
Shear Wall
wood/concrete/masonry - resist changes of shape and transfer cert loads to ground
foundation
Braced Frame - timber or steel
Knee brace
K-brace
Cross-brace
, What is the least effective way to achieve lateral stability? - answerRigid frame (only
appropriate in low-mid rise buildings)
What do vents and traps do in relation to plumbing design? - answerVents permit septic
gases to escape and prevent siphonage and backpressure
Traps - seal sewer gases from escaping the fixture
What is the difference between a soil stack and a waste stack? - answerSoil stack (vert
pipe) for urinals and WC's
Waste stack (vert pipe) from plumbing fixtures other than urinals or WC's
List considerations in specifying and designing HVAC systems: - answerPerformance -
technical and cost efficiency (capital and operating costs)
Fuel/Power source - regional availability and efficiency
Flexibility - to meet various demands throughout building
Noise and Vibration - relating to programmatic requirements
Space Consumption - how much room is req
Building size and configuration
What is the intent of Fire Protection Systems? - answerIntent is to protect building from
fire and contain fire long enough for safe evacuation of occupants, and long enough for
firefighters to respond
Why are Wet-Pipe sprinkler systems the most common? - answereasy to design,
easy to install,
easy to maintain,
cost less due to simplicity and design mechanics
Describe the 2 common types of elevators. - answerElectric:
Car mounted on side guide rails, lifted with hoisting cables, driven by electric hoisting
machinery in penthouse.
Geared traction elevs are medium speed and typically used in med-rise buildings
Gearless traction = high speed (up to 1,200 feet/min, or 6m/s) used for high rises
Hydraulic:
What is: Design wind pressure? - answer Design wind pressure:
Minimum design value for the equivalent static pressure on the exterior surfaces
resulting from critical wind velocity (equal to a reference wind wind pressure measured
at 33', 10m). The # is modified by a bunch of coefficients to account for: exposure
conditions, building height, wind gusts, geometry/orientation.
Why are horizontal forces more critical than vertical ones in seismic design? - answer
Because structures usually have considerable reserve for dealing with additional vertical
loads.
Define Base Shear. - answer Base shear:
Minimum design value for the total lateral seismic force (assumed to act in any
horizontal direction)
Define the following: Collinear Forces, Concurrent Forces, Nonconcurrent Forces. -
answer Collinear Forces:
Occur along straight line. Vector sum= sum of magnitude of forces acting along same
line of action.
Concurrent Forces:
Lines of action intersecting at common point. Vector sum=equivalent to, and produces
same effect on rigid body as the application of the vectors of the several forces.
Nonconcurrent Forces:
Lines of action that do not intersect at common point. Vector sum=single force that
would cause the same translation and rotation of a body as the set of original forces.
What is a moment (structural forces)? - answerMoment:
The tendency of a force to produce rotation of a body about a point or line
What is a Couple (structural forces)? - answerCouple:
Force system of 2 equal parallel forces acting in opposite directions tending to produce
rotation but not translation
What are beams designed to do? - answerDesigned to carry and transfer transverse
loads across to supporting elements.
Define Deflection - answerDeflection:
perp distance a spanning member deviates from true course under transverse loading
,What is the difference between a simple beam and a Fixed-End Beam? - answerSimple
Beam:
Rests on supports at both ends - no moment resistance (ends free to rotate)
Fixed-end beam:
Both ends fixed against translation and rotation (reduced max deflection, transferred
bending stresses, increased rigidity)
Distinguish between the following three frame types:
-Fixed Frame
-Hinged Frame
-Three Hinged Frame - answerFixed Frame
rigid frame connected to its supports with fixed joints (more resistant to deflection than
hinged from but also more sensitive to settlements and thermal expansion/contraction)
Hinged Frame -
Rigid frame connected to its joints with pinned connections (pinned connections prevent
high bending stresses by allowing rotation)
Three-hinged Frame - structural assembly of 2 rigid sections connected to each other
and to its supports with pin joints (more sensitive to deflection than fixed or hinged, 3-
hinged system is least affected by support settlements and thermal stresses - can also
be analyzed as a statically determinate structure
Name 1 kind of beam for each wood, steel, and concrete, that can span >60' (18m). -
answerWood:
Laminated Beams (Timber)
Trusses (Timber)
Steel:
OWSJ
Concrete:
Precast Tees
List three basic mechanisms for resisting lateral loads. - answerRigid Frame
steel or reinforced concrete with rigid joints
Shear Wall
wood/concrete/masonry - resist changes of shape and transfer cert loads to ground
foundation
Braced Frame - timber or steel
Knee brace
K-brace
Cross-brace
, What is the least effective way to achieve lateral stability? - answerRigid frame (only
appropriate in low-mid rise buildings)
What do vents and traps do in relation to plumbing design? - answerVents permit septic
gases to escape and prevent siphonage and backpressure
Traps - seal sewer gases from escaping the fixture
What is the difference between a soil stack and a waste stack? - answerSoil stack (vert
pipe) for urinals and WC's
Waste stack (vert pipe) from plumbing fixtures other than urinals or WC's
List considerations in specifying and designing HVAC systems: - answerPerformance -
technical and cost efficiency (capital and operating costs)
Fuel/Power source - regional availability and efficiency
Flexibility - to meet various demands throughout building
Noise and Vibration - relating to programmatic requirements
Space Consumption - how much room is req
Building size and configuration
What is the intent of Fire Protection Systems? - answerIntent is to protect building from
fire and contain fire long enough for safe evacuation of occupants, and long enough for
firefighters to respond
Why are Wet-Pipe sprinkler systems the most common? - answereasy to design,
easy to install,
easy to maintain,
cost less due to simplicity and design mechanics
Describe the 2 common types of elevators. - answerElectric:
Car mounted on side guide rails, lifted with hoisting cables, driven by electric hoisting
machinery in penthouse.
Geared traction elevs are medium speed and typically used in med-rise buildings
Gearless traction = high speed (up to 1,200 feet/min, or 6m/s) used for high rises
Hydraulic:
