Deep Foundations: (a) Pile Foundation (b) Deep Foundation
(a) Pile Foundation: When the soil strata near to the surface of the earth is weak and can not take the load of the super-structure, the load is to be transferred to the hard strata at the greater depths through piles or well foundations. Pile supports the structure by gaining the strength in two ways : i)friction of the surface of shaft with the soil and ii)end bearing support to pile.
Bearing capacity of a pile is the minimum load at which a pile continues to sink without any further increase in the load, it is called as the ultimate bearing capacity of the pile. Safe load which can be carried by a pile is determined on the basis of
(a) ultimate bearing capacity divided by some suitable factor of safety.
(b) Permissible settlement.
(c) Overall stability of the pile.
Now to classify the piles you can take the following bases:
(a) Classification based on the function of the piles:
(i) End Bearing Piles: In such piles the load is transferred to the hard strata through the end of the pile. The soil in between is soft and loose.
(ii) Friction Piles: In such piles the load is transferred to the soil through friction along the surface of the pile.
(iii) Compaction Piles: When the loose granular soil is compacted to increase the bearing capacity, compaction piles are used.
(iv) Tension Piles: Piles are used to anchor down the structures which are under the action of an uplift force has to bear the tension and so are called tension piles.
(v) Anchor Piles: Anchor piles are provided to provide anchor support against any horizontal pull.
(vi) Batter Piles: These piles are used to resist any horizontal or inclined pull due to moving ships etc.
(vii) Fender Piles and dolphins: These piles are constructed to protect the water front structures from the moving ships or floating objects.
(b) Based on method of installation:
(i) Pre-cast driven piles
(ii) Driven cast-in-situ piles
(iii) Bored cast-in-situ piles
(c) Based on Material Used:
(i) Concrete Piles
- Precast driven piles
- cast- in-situ piles
- pre-tested concrete piles
(ii) Timber Piles
(iii) Composite Piles
- Concrete and Timber Piles
- Concrete and steel piles
Well Foundations:
The depth of the well foundation is based on the following criterion :
(i) The well should be taken below scour depth called grip length
(ii) The well should be sunk to sufficient depth so as to satisfy requirement of bearing capacity.
(a) Pile Foundation: When the soil strata near to the surface of the earth is weak and can not take the load of the super-structure, the load is to be transferred to the hard strata at the greater depths through piles or well foundations. Pile supports the structure by gaining the strength in two ways : i)friction of the surface of shaft with the soil and ii)end bearing support to pile.
Bearing capacity of a pile is the minimum load at which a pile continues to sink without any further increase in the load, it is called as the ultimate bearing capacity of the pile. Safe load which can be carried by a pile is determined on the basis of
(a) ultimate bearing capacity divided by some suitable factor of safety.
(b) Permissible settlement.
(c) Overall stability of the pile.
Now to classify the piles you can take the following bases:
(a) Classification based on the function of the piles:
(i) End Bearing Piles: In such piles the load is transferred to the hard strata through the end of the pile. The soil in between is soft and loose.
(ii) Friction Piles: In such piles the load is transferred to the soil through friction along the surface of the pile.
(iii) Compaction Piles: When the loose granular soil is compacted to increase the bearing capacity, compaction piles are used.
(iv) Tension Piles: Piles are used to anchor down the structures which are under the action of an uplift force has to bear the tension and so are called tension piles.
(v) Anchor Piles: Anchor piles are provided to provide anchor support against any horizontal pull.
(vi) Batter Piles: These piles are used to resist any horizontal or inclined pull due to moving ships etc.
(vii) Fender Piles and dolphins: These piles are constructed to protect the water front structures from the moving ships or floating objects.
(b) Based on method of installation:
(i) Pre-cast driven piles
(ii) Driven cast-in-situ piles
(iii) Bored cast-in-situ piles
(c) Based on Material Used:
(i) Concrete Piles
- Precast driven piles
- cast- in-situ piles
- pre-tested concrete piles
(ii) Timber Piles
(iii) Composite Piles
- Concrete and Timber Piles
- Concrete and steel piles
Well Foundations:
The depth of the well foundation is based on the following criterion :
(i) The well should be taken below scour depth called grip length
(ii) The well should be sunk to sufficient depth so as to satisfy requirement of bearing capacity.
Sir u hve explained pile foundation in brief bt wat about well foundation? Plz explain well foundation in brief air!!!
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