Non-uniform soil:
The subsoil is considered to be relatively balanced in shape. It either extends to greater depths or extends to limited depths. In fact, such a balanced soil condition is not commonly observed. The previous articles did not provide a direct solution to the real problem. However, the real situation should be taken seriously.
Most of the subsoil is composed of more or less lenticular material. Some components of the pile are composed of resistant and non-compressible substances. Again some elements are weak and compressible. Based on preliminary data from standard penetration tests and laboratory tests in general, it is said that some parts of the subsoil are strong enough and uncompressible.
The main task of engineering before selecting the desired foundation is to determine the effect of weak elements. In general, the stress is determined by considering the subsoil as smooth and elastic. The ground disclosure information is used to determine the bearing capacity of a weak substance.
It is then compared with the following stresses to see if they are resistant without failure. The results of the observations are sufficient for the speech on an approximate basis. And to make the right decision, extensive geological and soil testing is required.
Soft or loose strate overlying firm strata:
When the topsoil is formed by soft or loose soil, it provides the characteristics of the soil, which may require adequate support in the future.
Therefore, a decision needs to be made as to whether a footing foundation can be provided for such soils. Decision making requires knowing the bearing capacity of the soil. Therefore the safe load of the topsoil is calculated based on the assumptions.
And in the soft part, the pressure is calculated from the pressure. If the following safe load is too low or the load is too high, it will be impossible to provide footing scholarship. So it is reasonable to give piles or piers periodically. Moreover, the pressure on the soil can be reduced by constructing raft foundations through excavation.
Dense or stiff layer overlying soft deposit:
Below the hard layer, soft soil piles are located in such a way that its depth is not clearly understood. If the importance of the hard layer is low and the footing applies sufficient pressure, it may break into the soft soil.
Different types of failures occur in this condition. If the thickness of the hard layer is more, it is able to prevent such failures. Due to consolidation, the fabric of the structure is more in soft soil.
The safe coefficient is calculated in such a way that the upper surface of the soft soil pile does not exceed the maximum pressure below the safe pressure to prevent failure i.e. to prevent it from breaking.
If the distance between the footings is greater and the thickness of the power layer is less than the width of the shooting, the pressure on the soft layer can be reduced by increasing the size of the footing.
On the other hand, when the position of the footing is close and the thickness of the hard layer is relatively high, the pressure distribution on the soft layer is not changed 'radically' by changing the clear impression.
Based on non-uniform soils
In the figure above (a) the pressure of each footing is applied at 20 tons per square meter and the maximum pressure falls on a similar soft mud layer at 8.4 tons per meter.
In Figure (b), and if the same amount of load has to be transferred to the solid level, doubling the footing area will reduce the contact pressure to 10 tons per square meter. The maximum pressure on the soft clay layer will be 6.8 tons per square meter. Here it has decreased by only 19 per cent.
On the other hand, if a raft foundation is used instead of footing and the same amount of load has to be carried, the slab above the soft mud layer is 6.4 tons per square meter, which cannot be reduced by more than 24 percent.
In such cases, even if the size of the footing is increased and the safe people cannot be reduced, support is provided with the help of piles. Moreover the pressure on the hard layer beneath the soft soil does not exceed the safe load bearing capacity, but the footing of the footing foundation will be excessive. If the amount of hey bachan is more then you have to choose another type of foundation instead of footing.
Alternating soft and stiff layer:
If the soil pile is made up of numerous weak layers, the load-bearing capacity and the weaving should be done separately for each layer. If the footing of the structure is unable to support the soil, piers or piles are used to transfer the load to the solid layer at sufficient depth.
Depth can be determined depending on the load bearing capacity and the position. The type of pile or pile or pile used is selected considering the difficulties of the soil.
It depends on the experience of placing the pile on the load level through the energy level. How deeply and accurately the pile can be placed in such a pile cannot be predicted until the test pile is placed.
Thus, in the case of such soils which can be constructed with the help of ribbons. Again piles or piers can be used.
Irregular deposit :
If the subsoil is composed of lenticular or wedge-shaped lumps, it is almost impossible to make an actual calculation of the load-bearing capacity of that soil. In such cases it is advisable to determine the general characteristics of the soil pile. Two methods are used to determine the soil properties of uneven mounds, such as: -
1) Through more sub-surface sounding.
2) Through a small number of boring and soil tests.
The purpose of determining the characteristics is to gain an idea about the distribution and size of the softest parts of the soil. Moreover unequal coordination is known. Boson's calculations are based on estimates.
What is meant by variable pile:
Some components of subsoil are composed of resistant and non-compressible materials, while some components are composed of weak and compressible materials. Such a mound of soil is known as the uneven soil.
What is meant by uneven soil?
Most of the subsoil is more or less composed of lentil-shaped material. Some of the components of this soil pile are made up of completely resistant and non-compressible material. Again, some elements may be composed of relatively weak and compressible substances. Such soil is called uneven soil.
How many types and what are the uneven soil layers?
There are four types of uneven soil layers.
A) soft or loose layer on hard layer,
B) dense or strength layer on soft layer,
C) Soft and hard layers in stages,
C) Variable pile.
What are the known characteristics of soil in variable piles?
The soil characteristics of the variable pile show that-
A) The size of the softest material in the pile,
B) description of the softest material of the pile,
C) Unequal coordination.
Non-uniform Soil is described as:
The subsoil is considered to be relatively balanced in shape. It either extends to greater depths or extends to limited depths. In fact, such soil conditions are not uncommon.
Most of the subsoil is composed of more or less lenticular material. Some components of the pile are composed of resistant and non-compressible substances. Again some elements are weak and compressible.
The standard penetration test and the general laboratory test are said to be based on preliminary data; Some parts of the subsoil are strong enough and uncompressible.
The characteristics of the periodic soft and hard layers are described as:
If the soil pile is made up of numerous weak layers, load bearing capacity and weaving should be done separately for each layer. If the footing of the structure is unable to support the soil, piers or piles are used to transfer the load to a level of sufficient depth.
The depth can be determined depending on the load bearing capacity and the sister. The type of pile or pile or pile used is selected considering the difficulties of the soil.
It depends on the experience of placing the pile or pier on the load level through the solid layer. How deep the pile can be placed correctly in such a pile cannot be predicted until the test pile is placed.
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Foundation