What is the difference between Safe Bearing Capacity and Gross Bearing Capacity?
Factors affecting the selection of foundation: Factors affecting the selection of foundation based on politics to basic criteria: Based on soil condition Based on loads from the building 1. based on soil condition: The shallow foundations are most preferred Foundation whenever the soil close to theRead more
Factors affecting the selection of foundation:
Factors affecting the selection of foundation based on politics to basic criteria:
- Based on soil condition
- Based on loads from the building
1. based on soil condition:
- The shallow foundations are most preferred Foundation whenever the soil close to the surface which is capable of support structural loads.
- Where ground close to the surface is not capable of supporting structural loads Din hard starter is used for the foundation is required.
- The stable ground requires Shallow Foundation whereas filled up Grounds has low bearing capacity thus requires deep Foundation.
2. based on loads from the building:
- In case of very low height building in a larger area than the extent of loading is relatively very slow and that’s why Shallow Foundation con resists the load from the structures.
- In the case of high rise building with less area and high amount of loads. In that case, the foundation is required. Because the shallow Foundation may not be able to resist such high loads of great intensity.
Thank you.
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Neenu S K
Hi, In gross bearing capacity, the gross load is taken. Loads from the superstructure, self-weight of the foundation, and overburden pressure are the gross loads. Gross bearing capacity value is not taken in design as it is very high. Safe bearing capacity is the bearing capacity value that neglectsRead more
Hi,
In gross bearing capacity, the gross load is taken. Loads from the superstructure, self-weight of the foundation, and overburden pressure are the gross loads. Gross bearing capacity value is not taken in design as it is very high.
Safe bearing capacity is the bearing capacity value that neglects the overburden pressure and stress due to the footing weight. It is obtained by considering the factor of safety, i.e. net load is taken into consideration. More detailed explanation is given below.
GROSS BEARING CAPACITY OF SOIL (qu)
NET ULTIMATE BEARING CAPACITY OF SOIL (qnu)
SAFE BEARING CAPACITY OF SOIL
- Safe Bearing capacity of soil is obtained after applying the factor of safety.
- It is divided into two:
- Safe Net Bearing Capacity
- Safe Gross Bearing Capacity
- Safe Net Bearing Capacity is defined as the net soil pressure that can be safely applied to the soil considering shear failure alone. It is obtained as qns = Net Ultimate Bearing Capacity (qnu)/Factor of Safety, i.e. qns = qnu/FS
- Safe Gross Bearing Capacity or Safe bearing Capacity is defined as the maximum gross pressure that soil can carry without shear failure. It is given by safe gross bearing capacity qs = qns + γDf
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