29 March 2017
1
Stresses in Soil Mass(Das, Chapter 10)
Bed Rock
Firm Ground
Shallow Foundations- Transferring building loads to underlying ground
- Mostly for firm soils or light loads
29 March 2017
2
Bed Rock
Weak Soil
Deep Foundations
PILE
- Transferring building loads to underlying ground- Mostly for weak soils or heavy loads
Embankment
29 March 2017
3
Stress in a Soil Mass Vertical stress due to a point load Vertical stress due to a vertical line load Vertical stress due to a vertical strip load Vertical stress due to embankment load Vertical stress below a center of a uniform loaded Circular area Vertical stress at any point below a uniformly loaded Circular area Vertical stress caused by rectangular load Influence chart for vertical pressure
Vertical Stress Due to a Point Load
29 March 2017
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Vertical Stress Due to a Vertical Line Load
Vertical Stress Due to a Vertical Strip Load(Finite width and infinite length)
Calculate Dsz /q from 2z /B and 2x /B
29 March 2017
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Vertical Stress Due to a Vertical Strip Load
Vertical Stress Due to Embankment Loading
I2 is a function of B1/z and B2/z
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Vertical Stress Due to Embankment Loading
Vertical Stress Below Center of Uniform Loaded Circular Area
D 2/312R/z
1 - 1 q zs
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Vertical Stress Below Center of Uniform Loaded Circular Area
Vertical Stress at Any Point Below a Uniformly Loaded Circular Area
29 March 2017
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Vertical Stress at Any Point Below a Uniformly Loaded Circular Area
Vertical Stress at Any Point Below a Uniformly Loaded Circular Area
29 March 2017
10
Vertical Stress Caused by Rectangular Load(under corner of the loading area)3Iq Ds
ZLZB
nm
I3 is a function of m and n
Vertical Stress Caused by Rectangular Load
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21
Vertical Stress Caused by Rectangular Load
Vertical Stress Caused by Rectangular Load)III (Iq 2(4)2(3)2(2)2(1) D zs
1 2
3 4