Exam 1 Flashcards
What is the intent of a building code?
To protect public health and safety by setting a minimum building safety
Organize these construction types by least to most fire-resistant:
1. heavy timber
2. ordinary construction, brick masonry bearing walls w interior wood/steel
3. site-cast concrete
4. light wood
5. fire-proofed steel
LEAST
1. light wood
2. heavy timber
3. ordinary construction
4. fire-proof steel
5. site-cast concrete
MOST
What is the point of a foundation?
Transfers structural load of the building safely into the ground
What are the 4 requirements for a successful foundation?
- safe
- settle uniformly across the building
- feasible
- no damage to anything around
What is the order of construction for foundations?
- conduct soil tests- digging (shallow) and boring (deep)
- excavation- site prepared & made safe for permanent construction of foundations. structures needed to hold Earth
- construction of foundations- shallow or deep systems
liquid limit of soil
the water content at which the soil passes from
plastic state to a liquid state.
plastic limit of soil
the water content at which the soil loses its
plasticity and begins to behave as a solid.
What is a tie back?
A commonly used method of bracing sheeting systems against soil and water pressure
What is excavation sheeting?
Provides a safe work zone for foundation construction. It is needed to brace the soil and prevent it from caving into the zone of excavation.
How are tie backs created?
- rotary drill bores a hole through slurry wall and into stable soil or rock. insert steel pipe casing to protect bored hole
- High strength pre-stressed steel tendons are inserted into the hole and grouted under pressure to secure to the soil
- tendons are tensioned by a hydraulic
jack and anchored to a horizontal steel
member, called a WALER.
What is a waler?
horizontal member used to provide lateral support for a vertical wall or excavation
What are the two foundation types and how do they work?
- shallow– transfer load to the earth at the base of column or wall or substructure
- deep– penetrate through layers of incompetent soil to transfer loads to competent bearing soil or bedrock below
How does a shallow foundation work?
Transfers the load to the earth at the base of column or wall of the substructure
How does a deep foundation work?
penetrate through layers of incompetent soil in order to transfer loads to competent bearing soil or bedrock below
What is superstructure?
above ground portion of the building
What is substructure?
habitable below ground section of a building
What are the foundations of a building?
Structure that transfers loads into the soil/earth
What are the two basic types of deep foundations?
Caissons (drilled) and piles (driven)
What is a caisson?
A type of deep foundation that is drilled through unsatisfactory soil to reach into bedrock or dense send or gravel. Permanent foundation supports made of concrete poured into drilled holes.
What are piles and how do they work?
A type of deep foundation that is driven to create pressure bulbs in unstable soil. Increasing the number of piles increases the bearing capacity of the soil and allows for a level substructure to be constructed on the pile field
caisson
drilled
pile
driven
What is a bell caisson
Spins around and creates bell shape for bottom of caisson
Be able to sketch a simple retaining wall
key- thickened part of footing to prevent sliding of wall
drainage layer– crushed stone or gravel, drain pipe where footing meets bottom of wall or weep holes
weep holes– individual draining pipes
What is a retaining wall?
sitecast reinforced concrete and reinforced concrete masonry to hold back earth
What is the difference between deep and shallow foundations?
- shallow– transfer load to the earth at the base of column or wall or substructure
- deep– penetrate through layers of incompetent soil to transfer loads to competent bearing soil or bedrock below
Formwork necessary to build true masonry arches is called…
(wooden) centering formwork
What is centering?
Formwork necessary to build true masonry arches
How are masonry arches built?
Wooden centering formwork is built, then arches arches are constructed, and the formwork is removed.
What are the ingredients of concrete?
portland cement
sand (fine aggregate)
gravel (course aggregate)
admixtures
What is an admixture?
ingredients that change the performance of concrete
What are some examples of ways that admixtures can change the performance of concrete?
increase curing rate
decrease curing rate
make extra strong
What is the difference between a one way and two way slab?
One way slab– rectilinear bays determined by column spacing
two-way slab- square bays
What is a one-way slab?
rectilinear bay determined by column spacing
What is a two-way slab?
square bays
What is clinker?
The raw materials of portland cement once they have been blended and burned
What are the 4 rules/guidelines for making high quality concrete?
- Use clean, sound, properly sized ingredients
- Mix ingredients in the proper proportions
- Handle the wet concrete properly to avoid segregating the ingredients
- Cure the concrete carefully under controlled conditions
What is the compressive strength of concrete needed for shallow foundations?
As low as 2,000 pounds per square inch (psi)
What is the compressive strength of concrete needed for columns used in a high rise building?
As high as 22,000 psi
How does the water/cement ratio affect the strength and surface quality of the concrete that is
produced?
More water than is needed for the curing of concrete is essential to allow the concrete
mixture to flow through pumps and to be placed properly into formwork. The less water in
the mix, the denser and stronger the concrete. Too much water will adversely affect the
surface quality, as complete filling of the formwork “mould” can be compromised.
What causes concrete to cure?
heat of hydration, not drying
What is a slump test?
sample the mix & measure its water content. measures how many inches the concrete “slumps” when taken out of metal mold. if it has too much water content/slumps too much– taken back to plant
What is the purpose of a slump test?
Check water content of concrete mix
What is conventional reinforcing called?
rebar
What are the increments of size for reinforcing steel bars?
1/8ths of an inch
What is the diameter of a eight bar reinforcing steel bar?
1 inch
Be able to sketch reinforcing steel location on a continuous beam
Remember to put the reinforcing at the columns & leave it out at the middle of the span. Have continuous lower bars throughout the spans
What is the difference between prestressing and post-tensioning?
Prestressing– done offsite in a factory.
Post-tensioning— on site. Currently more common
Who patented the first system of site-reinforced concrete construction?
Francois Hennebique
What did Francois Hennebique do?
Patent the 1st system of sitecast reinforced concrete construction
What is a slurry wall
A permanent excavation system
How is a slurry wall constructed?
- lay a trench guideline & dig a vertical trench
- pour slurry into trench to keep earth from collapsing into the trench
- lower reinforcing steel cage into trench
- concrete in pumped into trench, forcing slurry out of trench to be stored & reused
- after concrete cures, the earth is excavated within the construction zone & tie backs are drilled through slurry wall to secure further
What is slurry made of?
Bentonite mixed with water.
What properties of slurry make it appropriate for building a slurry wall for excavation?
Bentonite slurry can absorb huge amounts of groundwater and remain strong enough to hold back earth in a trench
What are the different project delivery methods?
- design bid build
- design/build
- construction management /program mngmnt
- integrated project delivery
What is design-bid-build project delivery?
owner hires 2 entities
features design and construction as two
separate phases of the project. For cost-savings, it is very common
to see owners establish “fast-track” project scheduling, where
construction begins before the final design is completed.
What else is design-bid-build called?
Traditional fixed-bid process
What is design/build project delivery scenario?
design and
construction services are offered from a single source (construction
company, contractor). The architect would work directly for the
contractor, or the company has their own architects in-house.
what is CONSTRUCTION MANAGEMENT project delivery?
The owner hires a construction manager, who
coordinates and oversees all aspects of the project –from design to
construction close-out, including the hiring of the architect, project
consultants (engineers) and builder (contractor)
What is INTEGRATED PROJECT DELIVERY (IPD) project delivery?
approach that
integrates people, systems, business structures and practices into a process that collaboratively harnesses the talents and insights of all participants to optimize project results, increase value to the owner,
reduce waste, and maximize efficiency through all phases of design, fabrication, and construction.
What is zoning?
local ordinances that dictate what can be built
where (and next to what), how large it may be, how tall, setbacks from streets and other buildings, parking requirements, transportation adjacencies, and sometimes
building materials.
What is a local ordinance that dictates what can be built where?
zoning
What do zoning ordinances govern typically?
- types of building uses and activities allowable on a parcel of land (i.e. housing, commercial)
- total floor area that a building can cover
- setbacks from properties lines
- allowable number of parking spots
- maximum building height
- non-combustible construction
What is the purpose of a building code?
to protect public health and safety by
setting a MINIMUM standard of construction quality
