Contents
- 1 How do you place a pile cap?
- 2 How is depth of pile cap determined?
- 3 What is a pile and pile cap?
- 4 How are pile caps measured?
- 5 How thick is a pile cap?
- 6 What is the depth of pile cap?
- 7 What is the purpose of pile cap?
- 8 How is concrete pile cap calculated?
- 9 When to use a pile foundation or a pile cap?
- 10 How are pile caps used to transfer load?
How do you place a pile cap?
Pile caps are constructed by excavating an area around the group of piles to enable formwork to be inserted. The pile tops may be trimmed to ensure they are at the same height. A reinforcement cage is then built and positioned in the formwork cast box and fastened to the piles.
How is depth of pile cap determined?
Consider the design of a pile cap supporting two pile and a single column on the pile cap. consider 150mm offset from the pile and space between piles as 2.5 times pile diameter. Effective depth, d = 1000-50-20/2 = 940 mm > 750mm; (2.5×600/2) Ok.
Where the pile cap is placed in a pile foundation?
It usually forms part of the deep foundation of a building, typically a multi-story building, structure or support base for heavy equipment, or of a bridge. The cast concrete pile cap distributes the load of the building into the piles.
What is a pile and pile cap?
Piles are used to carry the load of the structure deep into the ground, and pile caps form the solid foundation on which the piers are then built.
How are pile caps measured?
Wrap a length of string around the top of your pile (where a piling cap would go), and mark the length of the string (or cut it). Measure the string and then divide that number (the circumference) by 3.14159 (pi) to get the diameter of your pile.
What is the use of under reamed pile?
Provision of under reamed bulbs has the advantage of increasing the bearing and uplift capacities. It also provides better anchorage at greater depths. These piles are efficiently used in machine foundations, over bridges, electrical transmission tower foundation sand water tanks.
How thick is a pile cap?
The thickness of the pile cap t is a variable, which is between 0.5m and 3.0m. The diameter of piles is 0.5m, and the length is 8.5m. The center-to-center spacing of piles is 2.5 m. Both pile cap and piles are made of concrete.
What is the depth of pile cap?
Table: Pile cap depth for different pile diameters
| Pile Diameters (mm) | Depth of Pile Cap (mm) |
|---|---|
| 500 | 1100 |
| 550 | 1200 |
| 600 | 1400 |
| 750 | 1800 |
What is the purpose of designing pile cap?
These pile cap shapes minimize the plan area for a symmetrical arrangement of piles about the load. The pile cap should overhang the outer piles by at least 150mm but should not be excessive, generally not more than the diameter of the pile diameter.
What is the purpose of pile cap?
A pile cap is defined as a concrete block cast on the head of a group of piles, to transmit the load from the structure to the group of piles. Generally, pile cap transfers the load form the structures to a pile group, then the load further transfers to firm soil.
How is concrete pile cap calculated?
To work out the volume of pile concrete, the following formula is used: πr2h (here, r denotes pile radius and h denotes the height of pile) So, concrete volume = πr2h x 3 (because the numbers of pile caps are three)
How are piles arranged in a pile cap?
The pile cap is a mat-like structure which rests on the group of piles to transfer loads from the super structure. By IS 2911-2010, the pile cap could be arranged that the column’s load is spread at 45° out of the top of the cap.
When to use a pile foundation or a pile cap?
The pile is generally a strong cylinder structure which supports loads of superstructure and transfers it to the subsoil. The pile cap is constructed just above the pile. Pile foundation is used when the subsoil is weaker, but the superstructure load is too heavy to carry that by shallow footing, then we use a pile foundation structure.
How are pile caps used to transfer load?
The connection between the piles and the superstructure is commonly done by pile caps that, according to the NBR 6118, are volumetric structures used to transfer the load coming from the superstructure to the piles.
What should the AC be for a pile cap?
100As / Ac = 0.13 Similarly, other types of pile caps can also be designed following the same procedure. However, when the number of piles is increasing in a pile cap, the manual calculation becomes more complicated. Computer packages could be used for ease of design while verifying the design outcome with simple calculations.