Building construction - FOUNDATION.pptx

Foundation and its types

1. FOUNDATION SHALLOW FOUNDATION DEEP FOUNDATION Wall foundation Combined foundation Mat or raft foundation Grillage foundation Pile foundation Under reamed foundation Well foundation Isolated column foundation

2. SHALLOW & DEEP FOUNDATION 1. Calculate the loads acting on the footing. 2. Obtain a soil profile or soil profiles showing the soil stratification at the site. 3. Establish the maximum water level. 4. Obtain the pertinent field and laboratory measurements and test results. 5. Determine the depth and location of the footing. 6. Determine the bearing capacity of the supporting stratum. 7. Proportion the footing sizes. 8. Check the footing contact pressure. SOURCES- https://civilseek.com/shallow-foundation-its-types-design/ https://www.slideshare.net/khushi9922/chapter-3-shallow-foundations 9. Check the stability of the footing against sliding, overturning, and uplift pressures. 10. Estimate the total and differential settlements. 11. Design the footing structure. 12. Assess the need for foundation drains, waterproofing or damp proofing

3. SHALLOW FOUNDATION

4. WALL FOUNDATION Wall footings are used to support structural walls that carry loads for other floors or to support nonstructural walls. All structural load-bearing walls must bear on footings.

5. WALL FOUNDATION The footings in turn distribute the loads to the soil. If the loading on the soil exceeds the soil bearing capacity, undesirable settlement will occur, resulting in cracked walls, uneven floors, or potentially structural failure in extreme overloading. AN EXAMPLE OF WALL FOUNDATION FORMWORK FOR WALL FOUNDATION

6. ISOLATED COLUMN FOUNDATION Isolated or single footings are used to support single columns. This is one of the most economical types of footings and is used when columns are spaced at relatively long distances.

7. ISOLATED COLUMN FOUNDATION SLOPED/ TRAPEZOIDAL FOOTING FORMWORK FOR A SINGLE FOOTING

8. ISOLATED COLUMN FOUNDATION

9. COMBINED FOUNDATION

10. Combined footings usually support two columns, or three columns not in a row. Combined footings are used when two columns are so close that single footings cannot be used or when one column is located at or near a property line. COMBINED FOUNDATION

11. MAT OR RAFT FOUNDATION This foundation extends below the entire building and distributes the load from multiple columns and walls of the structure to the soil below. It may be used for an entire building or a portion of the building to carry very heavy load. They are sometimes used to resist water pressures when groundwater extends above the level of the floor of the lowest basement of a building

12. MAT OR RAFT FOUNDATION

13. GRILLAGE FOUNDATION A foundation consisting of two or more steel beams, in single or double tier grillage, embedded in cement concrete is called Grillage Foundation. It is used when the load is heavy and the S.B.C. is poor.

14. DEEP FOUNDATION

15. PILE FOUNDATION Pile foundation is used where it is not possible simple spread foundation at a suitable depth because the stratum of required bearing capacity is at a greater depth or where there are steep slopes. Piles are classified as: Timber Piles, Concrete Piles, Composite or Steel Piles.

16. PILE FOUNDATION A Pile foundation has a base of cement concrete or steel grillage foundation supported by piles. http://www.quantity-takeoff.com/types-of-pile-foundation.htm

17. UNDER-REAMED PILE FOUNDATION https://www.slideshare.net/khushi9922/chapter-3-shallow-foundations A pile having one bulb is known as single under-reamed pile. It is seen that the load bearing capacity of the pile can be increased by increasing the number of bulb at the base. In such a case the pile is named as multi-under-reamed pile. Under-reamed piles are bored cast-in-situ concrete piles having bulb shaped enlargement near base. These piles are commonly recommended for providing safe and economical foundations in expansive soils such as black cotton soil having poor bearing capacity. In these type of foundation the structure is anchored to the ground at a depth where ground movement due to changes in moisture content negligible.

18. WELL FOUNDATION A foundation in the form of masonry or concrete well sunk in the ground is called WELL FOUNDATION. CUTTING EDGE CURB STEINING BOTTOM PLUG TOP PLUG WELL CAP PIER WELL FOUNDATION SAND FIILING

19. WELL FOUNDATION Such a foundation is provided where the soil is soft and sandy. In well foundation each well is provided with a curb of wood, mild steel or R.C.C. at bottom

20. FAILURE OF FOUNDATION Non-uniform settlement of subsoil and masonry Horizontal movement of the soil adjacent to structure Lateral pressure due to lateral movement of earth tending to overturn the structure Roots of trees and shrubs Unequal settlement of masonry. Shrinkage due to with drawl of moisture from soil below the foundation. Action of atmosphere. Lateral movement of soil below foundation. Horizontal significant impact. http://911-engineers.blogspot.com/2007/04/how-world-trade-center-fell.html