Lecture 14 Ai Flashcards
What are the three parts of a building?
Superstructure, substructure, and foundation system
What is a foundation?
The lower part of a building that supports the weight of the structure and transmits it to the ground
What materials are typically used for foundations?
- Concrete
- Masonry
- Combination of both
What are shallow foundations used for?
Buildings with light loads
What do deep foundations consist of?
- Driven piles
- Drilled shafts
- Auger-cast piles
What is a combined foundation?
A combination of shallow and deep foundations
What is the primary purpose of a footing?
To distribute the superimposed load on a large area of the soil
What are continuous wall footings also known as?
Strip footings
Fill in the blank: A _______ footing is used where the superimposed load is a point load.
Isolated
What is a combined footing used for?
Where two or more adjacent columns are closely spaced and heavily loaded
What are the three types of monolithic concrete foundations?
- Slab-on-ground foundation
- Mat foundation
- Raft foundation
What is a slab-on-ground foundation?
A widely used monolithic foundation system for low-rise buildings
What is a mat foundation used for?
Where the bearing capacity of the soil is low
What is a raft foundation also known as?
Floating foundation
What are deep-foundation systems made of?
- Piles
- Drilled piers
What is the difference between a friction pile and an end-bearing pile?
- Friction pile: Resists loads by skin friction
- End-bearing pile: Resists loads by end bearing
What are caissons?
Concrete cylinders poured into drilled holes
Fill in the blank: Piles are driven into the _______.
Earth
What materials are used for concrete piles?
- Precast concrete
- Solid concrete
What type of coating is used for steel piles in corrosive environments?
Protective coatings
What is a helical pile?
A type of screw pile that transfers loads from shallow footing to stronger underlying stratum
What is the function of a pile cap?
Functions like an isolated column footing or continuous strip footing under a wall
What is ignored for piles driven in weak soils?
The end reaction from tip bearing
This is due to the weak soil conditions not providing adequate support.
How do the cross-section sizes of piles compare to drilled piers?
Piles are smaller in cross-section than drilled piers
This size difference affects load capacities.
How many piles are typically used in a cluster for weak soils?
Three
This clustering helps to increase load capacity.
What is the function of a pile cap?
Functions like an isolated column footing or a continuous strip footing under a wall
This helps distribute loads from the structure to the piles.
What does a single friction pile do with its load?
Transmits its load into the earth as an equal shear pressure along the bulb profile
The bulb profile is indicated by a dotted line in diagrams.
What happens as the size of the pile cluster increases?
The piles act together to create a single larger bulb of higher pressure
This bulb reaches deeper into the ground, affecting load distribution.
What is the effect of a building with many closely spaced clusters of piles?
Creates a very large, deep bulb
This can lead to increased load capacity but requires careful design.
What must be ensured regarding large-pressure bulbs?
They do not overstress the soil or cause excessive settlement of the foundation
Overstressing can lead to structural issues.
How does the settlement of a large group of friction piles in clay compare to that of a single isolated pile?
Considerably greater
This highlights the importance of soil conditions in foundation design.
Who are the authors of the reference ‘Building construction: Principles, materials, and systems’?
Mehta, M., Scarborough, W., & Armpriest, D.
Published in 2013.
What year was ‘Fundamentals of building construction: materials and methods’ published?
2019
Authors are Allen, E., & Iano, J.
