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How to Design & Construct a House to Withstand 150 MPH Wind


Quiz Questions

 

1.The definition of the dead load is: The definition of dead load in ASCE 7-98 is “.the weight of all materials of construction incorporated into the building, including but not limited to walls, floors, roofs, ceilings, stairways, built-in partitions, finishes, cladding, and other similarly incorporated architectural and structural items, and fixed service equipment.” The sum of the dead loads of all the individual components will equal the unoccupied weight of the building.
True
False
2. Determining dead loads is important for several reasons:

  • Foundation size (e.g., footing width, pile embedment depth, number of piles) depends partly on dead load.
  • Dead load counterbalances uplift forces due to buoyancy and wind.
  • Dead load counterbalances wind and earthquake overturning moments.
  • Dead load changes the response of the building to both seismic forces and impact forces generated by floating objects.
True
False
3.The design flood will always be greater than or equal base flood.
True
False
4.Hydrostatic loads occur when standing or slowly moving water comes into contact with a building or building component. Hydrostatic loads can act laterally or vertically, and the forces they exert include buoyant or  flotation forces.
True
False
5.Wave forces can be separated into four categories:

  • Foundation size (e.g., footing width, pile embedment depth, number of piles) depends partly on dead load.
  • Those from non-breaking waves (these forces can usually be computed as hydrostatic forces against walls and hydrodynamic forces against piles)
  • Those from breaking waves (these forces will be of short duration, but large magnitude)
  • Those from broken waves (these forces are similar to hydrodynamic forces caused by flowing or surging
    water)
  • Uplift (these forces are often caused by wave run-up, deflection, or peaking against the underside of horizontal surfaces)

Of these, the forces from breaking waves are the highest and produce the most severe loads. Therefore, this manual strongly recommends that the breaking wave load be used as the design wave load.

True
False
6.Waves and currents during coastal flood conditions are capable of creating turbulence around foundation elements, and causing localized scour around those elements. Determining potential scour is critical in designing coastal foundations to ensure that failure during and after flooding does not occur as a result of the loss in either bearing capacity or anchoring resistance around the posts, piles, piers, columns, footings, or walls. Localized scour determinations will require knowledge of the flood depth, flow conditions, soil characteristics, and foundation type.
True
False
7.The design process involves the following:

  • Determining design loads
  • Determining the building’s foundation, structural frame, and envelope
  • Determining the connections between individual elements
  • Determining the elevation, placement, and support for utilities
  • Selecting the appropriate materials

The entire design process is based on the fundamental premise that anticipated service and natural hazard loads can and must be transferred through the building in a continuous path to the supporting soils. ANY weakness in that continuous path is a potential point of failure of the building, and any failure creates the possibility for large property losses and the potential for loss of life.

True
False
8.The types of loads that most commonly act on one- to three-story residential buildings during severe natural hazard events are as follows:

  • dead loads
  • live loads
  • flood loads
  • wind loads
  • earthquake (seismic) loads
  • snow loads
True
False
9.The dead loads are; the weight of the building and accessory equipment such as tanks, piping, electrical service panels and conduits, and HVAC equipment.
True
False
10.The live loads are; combined loads of occupants, furnishings, and non-fixed equipment.
True
False
11.Flood loads are based on flood depth and velocity, wave effects, expected long-term and short-term erosion as well as localized scour, elevation of the building in relationship to the expected flood conditions, and floating debris impacts.
True
False
12.Wind loads are based on Roof shape and pitch, sitting, topography and exposure, and building shape and orientation. The height of the structure also needs to be assessed.
True
False
13.Seismic loads are calculated based on mass (including elevation, location, and distribution) of the building, soil supporting the building, height of the building above the ground, and additional loads that the building may occasionally support (e.g., snow).
True
False
14.Snow loads are based on roof shape and pitch, multi-level roofs, and building orientation. Also, drifting snow may cause unbalanced loading on the roof system
True
False
15.The following concepts show how one design step leads to the next:

  • All design loads create forces in and on the building. The forces are transferred through load paths.
  • Load paths always end in the soil that supports the structure.
  • Loads should be applied to the building beginning at the top.
  • Loads should be determined for both the vertical and horizontal load paths.
  • Load transfer creates forces at connections and imparts stresses materials. Connections and materials must be strong enough to those forces and stresses.
  • The load path must be continuous; any break or weakness in the path “chain” can result in damage or even structural failure.
True
False
16.The following failure modes are:

  • Uplift: Vertical forces caused by wind or buoyancy exceed the weight of the structure and the strength of the soil anchorage. The building fails by being lifted off its foundation or because the foundation pulls out of the soil.
  • Overturning: The applied moments caused by wind, wave, earthquake, and buoyancy forces exceed the resisting moments of the building’s weight and anchorage. The building fails by rotating off its foundation or because the foundation rotates out of the soil.
  • Sliding or Shearing: Horizontal forces exceed the friction force or strength of the foundation. The building fails by sliding off its foundation, by shear failure of components transferring loads to its foundation, or by the foundation sliding.
Primary failure mode
Secondary failure mode
17.According to table 12.6 if you are nailing on the panel edges of the roof, the spacing for the nails in Zone I should be:
3 inches apart
4 inches apart
8 inches apart
18.In figures 12.74 the purpose of the link #2 connection between the roof rafter and the top plate of the exterior wall is:
It seems like a good way to connect the roof to the wall
To add shear strength and resist the uplift and lateral load.
19.Figure 12.83 shows how the fire-resistant walls and roof of one house helped it survived a wildfire surrounding houses were destroyed.
True
False
20.Figure 13.3 and 13.4 show an example of improperly and properly notched foundation pile.
True
False
21.Which one of the following tasks should be considered when examining the site soils before designing the foundation.
Soil borings
A review of borings from nearby sites
A test pit dug at or near one of the pilings or foundation corners
Information from the local office of the Natural Resource Conservation Service (formerly Soil Conservation Service) and Soil Surveys published for each county
Test piles
All of the above
22.Diagonal bracing strengthens and stiffens the pile foundation at the cost of greater exposure to wave and debris impact.
True
False
23.The following is a top foundation issue for builders

  • Piles, piers, or columns must be properly aligned.
  • The piles, piers, or columns must be driven or placed at the proper elevation to resist failure and must extend below the expected depth of scour and erosion.
  • Foundation materials must be flood damage-resistant (pressure treated wood, masonry, concrete).
  • Provide adequate support at the top of the foundation element to properly attach the floor framing system. Do not notch a wood foundation element more than 50 percent of its cross-sectional area.
  • Breakaway walls are intended to fail; do not overnail these walls to the foundations; do not install utilities or other obstructions behind these walls; do not finish inside these walls.
  • Where foundation elements are masonry or concrete (except slabson-grade), place the proper size of reinforcing, the proper number of steel bars, and provide the proper concrete cover over the steel.
  • Exposed steel in the foundation will corrode; plan for it by installing hot-dipped galvanized or stainless steel.
  • Areas of pressure-treated wood that have been cut or drilled will retain water and will decay; treat these cut areas in the field.
True
False
24.In figure 13.26 the purpose of full length board sheathing is:.
To transfer more of the shear loads between the frame joists
To cover the building.
25.In coastal structures the key to reduced long-term maintenance is the initial selection of appropriate materials and proper construction. Maintenance and repair demands will be directly influenced by decisions made during building design and construction.
True
False
26.To maintain maximum building performance, a coastal building’s structural system and envelope (i.e., exterior wall covering, doors, windows, and roof covering) must not be allowed to deteriorate. If the building is significantly degraded by corrosion, wood decay, termite attack, or weathering, its vulnerability to damage from natural hazards is increased.
True
False
27.The likelihood of termite infestation in coastal buildings can be reduced by maintenance that makes the building site drier and otherwise less hospitable to termites:

  • Store firewood and other wood items, including wood mulch, on the ground, away from the building.
  • Keep gutters and downspouts in good repair and positioned to direct water away from the building.
  • Keep water pipes, water fixtures, and drainpipes in good repair.
  • Avoid dampness in crawlspaces by providing adequate ventilation or installing impervious ground cover membranes.
  • Avoid frequent plant watering adjacent to the house, and keep plants trimmed away from the walls.
True
False
28.The combined effects of sun and water on many building materials, particularly wood, cause weathering effects, which include the following:

  • Fading of finishes
  • Accelerated checking and splitting of wood
  • Gradual loss of thickness of wood
True
False