1. Foundation Engineering CE 483
5. Settlement of shallow foundations
Copy right reserved to Dr O. Hamza

2. CE 483 - Foundation Engineering - 5. Settlement of shallow foundations
CONTENTS
Introduction
Vertical stress increase in a soil mass ..caused by foundation load
Elastic settlement calculation
Consolidation settlement calculation
Field test (Bearing capacity with .Settlement consideration)
References
CE Foundation Engineering Settlement of shallow foundations

3. CE 483 - Foundation Engineering - 5. Settlement of shallow foundations
Introduction
Principal criteria for foundation design
Types of settlements
Things required to calculate settlements
Three Ws  three dimensions to find a space
Copy right reserved to Dr O. Hamza
CE Foundation Engineering Settlement of shallow foundations

4. CE 483 - Foundation Engineering - 5. Settlement of shallow foundations
Introduction
Principal criteria for foundation design
When designing foundations, two principal criteria must be satisfied:
Maintaining Stability
Limiting Settlement
Stability against
Bearing failure
CE Foundation Engineering Settlement of shallow foundations

5. Principal criteria for foundation design
Introduction
Principal criteria for foundation design
When designing foundations, two principal criteria must be satisfied:
Maintaining Stability
Limiting Settlement
Crack
Soft ground
Embankment and building constructed on
soft ground (highly comprisable soil)

6. CE 483 - Foundation Engineering - 5. Settlement of shallow foundations
Introduction
Principal criteria for foundation design
Therefore, the allowable bearing capacity qall should be the smaller of the following two:
You learned how to calculate this (see previous chapter)
The safe pressure that does not cause bearing failure
The safe pressure that does not cause unacceptable settlement
You will learn (in this chapter) how to estimate settlement
CE Foundation Engineering Settlement of shallow foundations

7. CE 483 - Foundation Engineering - 5. Settlement of shallow foundations
Introduction
Types of settlements
From structural consideration there are two types of settlements:
Uniform settlement
Differential settlement
should be within the acceptable limit - given in the building code
CE Foundation Engineering Settlement of shallow foundations

8. Types of settlements Introduction
From geotechnical consideration, there are two types of settlements:
Immediate (or elastic) settlement, (mostly during construction time)
Consolidation settlement (occurs over long period of time)
Primary consolidation,
Secondary consolidation,
End of Construction
Time, t
Settlement, S

9. Primary consolidation settlement Secondary consolidation or creep
Introduction
Types of settlements
So, the total soil settlement ST may be contain one or more of these types:
Immediate settlement
elastic deformation with no change in water content
occurs rapidly during the application of load
occurs in sandy, silty and clayey soils
Primary consolidation settlement
decrease in voids volume as pore-water is squeezed out of the soil
occurs slowly according to the permeability
only significant in saturated clays and silts
Secondary consolidation or creep
due to gradual changes in the particulate structure of the soil
occurs very slowly, long after the primary consolidation is completed
most significant in soft organic soils

10. Types of settlements ST = Se + Sc + Ss
Introduction
Types of settlements
The total settlement of a foundation can then be given as:
ST = Se + Sc + Ss
What information do we need to know
to calculate these settlements?

11. Things required to calculate settlements
Introduction
Things required to calculate settlements
Methods used for settlement calculations usually require to know the followings:
Net foundation load
q [kPa]
Foundation (net load q, type, dimensions (B,L), Rigidity, …)
Vertical stress increase Ds in soil caused by foundation load Ds
Soil profile & parameters:
e.g. E, n, Cc, CR, …
Pressure bulb

12. Vertical stress increase in a soil mass caused by foundation load
Pressure bulb
Stress due to a concentrated load
Stress due to a circularly loaded area
Stress due to vertical line load
Stress below rectangular area
Average vertical stress increases in a layer
Approximate method
Three Ws  three dimensions to find a space
CE Foundation Engineering Settlement of shallow foundations

13. Vertical stress increase in a soil mass caused by foundation load
Pressure bulb
Structure built on ground causes increase in vertical stress (pressure) in the soil below.
Net foundation load
q [kPa]
This pressure increase is distributed to the soil in the form of a pressure bulb (or pressure isobars).
The stresses Ds of the pressure bulb is determined by elastic theory. Ds
Pressure bulb

14. Vertical stress increase in a soil mass caused by foundation load
Pressure bulb
The size and shape of the pressure bulbs depend on the size and shape of the loaded area e.g. point load, circular or rectangular loaded area, …et. 2B 2b B
q= 100 kPa
0.1 q
0.2 q
Ds =
Pressure bulbs under large
and small round foundations

15. Vertical stress increase in a soil mass caused by foundation load
Pressure bulb
Comparison between Pressure Bulb for square and strip footings

16. Vertical stress increase in a soil mass caused by foundation load
Stress due to a concentrated load
Boussinesq solution (1885) z
CE Foundation Engineering Settlement of shallow foundations

17. Vertical stress increase in a soil mass caused by foundation load
Stress due to a circularly loaded area z
CE Foundation Engineering Settlement of shallow foundations

18. Vertical stress increase in a soil mass caused by foundation load
Stress due to vertical line load z
CE Foundation Engineering Settlement of shallow foundations

19. Vertical stress increase in a soil mass caused by foundation load
Stress below rectangular area
The vertical stress at a depth, z, below the corner of a rectangular subject to uniform pressure is: l q b l
Dsv = q. I  b
Dsv
where:
q is the bearing pressure (net applied loading).
I is influence factor related to the shape of the loaded area. It is given by the following equation (Newmark, 1935):
decreases with depth z I
CE Foundation Engineering Settlement of shallow foundations

20. Vertical stress increase in a soil mass caused by foundation load
Stress below rectangular area m
n = 0.1
I  

21. Vertical stress increase in a soil mass caused by foundation load
Stress below rectangular area
To work out the vertical stress increase below the center of foundation, use:
l = ½ L
b = ½ B
Dsv = 4 q. I  
where:
L: foundation length
B: foundation width L l b l B b
Dsv
Dsv

22. Vertical stress increase in a soil mass caused by foundation load
Stress below rectangular area
Q=1000 kN
Example problem
1.5m
The figure shows 2.5m-square footing constructed in sand layer underlain by clay. Calculate the increase of effective pressure in the clay layer (at the top, middle and bottom) using Newmark method.
2.5x2.5m 3m
Dry sand
Sand 3m 3m
Clay
Key solution:
Let’s assume ’t , ’m and ’b represent the increase in the effective pressure at the top, middle, and bottom of the clay, respectively, under the center of the footing.
Bed rock z

23. Vertical stress increase in a soil mass caused by foundation load
Stress below rectangular area
Q=1000 kN
Key solution (cont..):
1.5m
2.5 x 2.5m 3m
l = ½ L = b = ½ B = 2.5/ 2 = 1.25 m
Ds’ = 4 q. I  
= 4 (1000/2.52) I
= 640 I
Dry sand
Sand 3m
’t
’m 3m
Clay Z
m = l/z
n = b/z I
Ds’ [kPa]
4.5 6
7.5
’b
Bed rock z
From the chart

24. Vertical stress increase in a soil mass caused by foundation load
Average vertical stress increases in a layer q
The increase in the vertical stress ’z in soil caused by a load q, applied over a limited area decreases with depth z
Compressible Layer z
’z under the center of foundation varies parabolically

25. Vertical stress increase in a soil mass caused by foundation load
Average vertical stress increases in a layer q
For settlement calculation, we can use the average pressure increase ’av , using weighted average method (Simpson’s rule):
Compressible Layer z
where:
’t , ’m and ’b represent the increase in the effective pressure at the top, middle, and bottom of the layer, respectively.
’z under the center of foundation

26. Vertical stress increase in a soil mass caused by foundation load
Approximate methods
For wide uniformly distributed load, such as for vey wide embankment fill, the stress increase at any depth, z, can be given as:
q kPa GL
soil z
z = q  z
does not decreases with depth z

27. Vertical stress increase in a soil mass caused by foundation load
Approximate methods
For other cases, the vertical stress at any depth, z, can be calculated using 2:1 linear distribution method. q
2 vertical to 1 horizontal B
2 vertical to 1 horizontal Z
B + Z
2:1 method of finding stress increase under a foundation

28. Vertical stress increase in a soil mass caused by foundation load
Approximate methods Z Z Z
decrease with depth z

29. Vertical stress increase in a soil mass caused by foundation load
Approximate methods
Average pressure increase q
For settlement calculation of a soil layer we usually use the average pressure increase ’av
Based on the “Approximate Method”, ’av can be considered at the middle of the layer:
Linear distribution H
Compressible Layer z
where ’m is the increase in the effective pressure at the middle of the layer.

30. Vertical stress increase in a soil mass caused by foundation load
Approximate methods
q=100 kPa
Example problem
The following figure presents a rectangular foundation with length L= 3m and width B =2m. The net applied pressure is 100kPa.
The ground profile consists of a clay layer of H=4m high. Sand is presented below and above this clay.
What is the increase of the effective pressure ’ at the middle of the layer caused by the foundation loading q ?
(use the approximate method) 1m
Sand
2:1 H
Clay
Sand z

31. Vertical stress increase in a soil mass caused by foundation load
Approximate methods
Example problem- key solution
Using 2:1 linear distribution of approximate method, ’ at the middle of the layer can be calculated from:
For Rectangular Foundation
where Z = ? = ……

32. Elastic settlement calculation
Contact Pressure and Settlement Profile
Settlement based on general theory of Elasticity
Elastic Settlement of saturated clay
Elastic Settlement of sandy soil: use of strain .influence factor
Three Ws  three dimensions to find a space
CE Foundation Engineering Settlement of shallow foundations

33. Elastic settlement calculation
Contact Pressure and Settlement Profile
The contact pressure distribution and settlement profile under the foundation are not uniform and will depend on:
flexibility of the foundation (flexible or rigid).
type of soil (clay, silt, sand, or gravel).
Contact pressure distribution
Contact pressure distribution
flexible
flexible
SAND
Settlement profile
CLAY
Settlement profile
rigid
rigid
CE Geotechnical Engineering II Compressibility of Soil
SAND
CLAY 33

34. Elastic settlement calculation
Settlement based on theory of Elasticity
integration of vertical strain ez
Settlement Se =
CE Foundation Engineering Settlement of shallow foundations

35. Elastic settlement calculation
Settlement based on theory of Elasticity
For flexible shallow foundation subjected to a net force per unit area equal to Ds : q q
(flexible)
(based on elastic theory)
More details about the calculation are given in Section 5.10 (Das, 2011).
rigid

36. Elastic settlement calculation
Settlement based on theory of Elasticity q
Thick foundation
Thin foundation
CE Foundation Engineering Settlement of shallow foundations

37. Elastic settlement calculation
Settlement based on theory of Elasticity B
Es(1)
Es(2)
Es(3)
Due to the nonhomogeneous nature of soil deposits, the magnitude of Es may vary with depth. For that reason, Bowles (1987) recommended using a weighted average value of Es. H
where:
Es(i) soil modulus of elasticity within a depth Dz.
whichever is smaller
CE Foundation Engineering Settlement of shallow foundations

38. Elastic settlement calculation
Elastic Settlement of saturated clay
Section 5.9 (Das, 2011)

39. Elastic settlement calculation
Elastic Settlement of saturated clay

40. Elastic settlement calculation
Elastic Settlement of sandy soil: use of strain influence factor
(changes with depth)
(applied by the foundation)
(changes with depth)

41. Elastic settlement calculation
Elastic Settlement of sandy soil: use of strain influence factor

42. Elastic settlement calculation
Elastic Settlement of sandy soil: use of strain influence factor
is obtained from CPT test
1 ≤ L/B ≤10 
by interpolation we can find: E qc qc
How about if there is no CPT date available?

43. Elastic settlement calculation
Elastic Settlement of sandy soil: use of strain influence factor
Note
Use

44. Elastic settlement calculation
Elastic Settlement of sandy soil: use of strain influence factor
Maximum stain influence factor
Izp
Initial value
Iz0 Z1
The strain influence factor Iz can be graphically presented by this diagram
Why does strain influence factor take this shape? Z2

45. Elastic settlement calculation
Elastic Settlement of sandy soil: use of strain influence factor
Izp
Iz0
= Iz0
= Izp or Iz(m) Z1 Z1
(required for the calculation of Izp) Z2 Z2
= 0
Depth of influence

46. Elastic settlement calculation
Elastic Settlement of sandy soil: use of strain influence factor
Izp
Iz0 Z1 L
Iz diagram varies with L/B
Variables Z2

47. Elastic settlement calculation
Elastic Settlement of sandy soil: use of strain influence factor z Z
Izp
Z2 =2B
Z2 =
Z2 = 4B
Z1=B
Z1=0.5B Z1 2
Iz0
10 ≤ L/B
Square
General case
L/B = 1
Strip footing
1 ≤ L/B ≤10
(Axisymmetric)
(Plane strain)

48. Elastic settlement calculation
Elastic Settlement of sandy soil: use of strain influence factor
Table summary of Iz profile Z1 Z0 Z1 Z2 Z2 Z
Calculated by interpolation between Case 1 and Case 3 *

49. Elastic settlement calculationZ1 Z2

50. Elastic settlement calculation
Elastic Settlement of sandy soil: use of strain influence factor 1.
Square
L/B = 1
General case
1 ≤ L/B ≤10
Strip
10 ≤ L/B Z Iz
0.1
0.2
0.5B B 2B 4B 2. 3. Z1 * Z2 *
Izp
Izp=
Izp 2 *
Calculated by interpolation between Case 1 and Case 3 *

51. Elastic settlement calculation
Elastic Settlement of sandy soil: use of strain influence factor Z1 Z2

52. Class example
In preparation for settlement calculation using strain influence method, the soil is divided to smaller layers. Explain why the soil is divided to 10 layers?

53. Elastic settlement calculation
Elastic Settlement of sandy soil: use of strain influence factor
Class example
A 3 m wide strip foundation on a deposit of sand layer is shown along with the variation of modulus of elasticity of the soil (Es). The unit weight of sand is 18 kN/m3.
Calculate the elastic settlement of foundation using the strain influence factor. Assume there is a creep over a period of 10 years.
Solution

54. Elastic settlement calculation
Elastic Settlement of sandy soil: use of strain influence factor
Solution
First step is to plot the variation of strain influence factor Iz with depth (to scale).
Strip footing
10 ≤ L/B Z Iz
0.2
B=3
4B=12
Izp
= 18 x ( ) = ….

55. Elastic settlement calculation
Elastic Settlement of sandy soil: use of strain influence factor
Solution (cont..)
Es profile is given.
We divide the soil into a number of layers depending on the variation of Iz and Es values with depth.
Then prepare the following table:

56. Elastic settlement calculation
Elastic Settlement of sandy soil: use of strain influence factor
Solution (cont..)

57. Elastic settlement calculation
Elastic Settlement of sandy soil: use of strain influence factor
More examples are given in Das’s text book – Section 5.12

58. Consolidation settlement calculation
Basic consolidation process
Laboratory Consolidation Test
Soil compressibility parameters
Normally Consolidated and Overconsolidated Clays
Calculation of Primary Consolidation Settlement
Secondary Consolidation Settlement
Three Ws  three dimensions to find a space
CE Foundation Engineering Settlement of shallow foundations

59. Consolidation settlement calculation
Basic consolidation process
When a saturated soil is loaded,
coarse soils
Time (months or years)
Settlement
saturated soil GL
Fine soils
in coarse soils (sand & gravel) the settlement takes place instantaneously. How can this be explained?
in fine soils (clay & silt): settlement takes far much more time to complete. Why?
CE Foundation Engineering Settlement of shallow foundations

60. Consolidation settlement calculation
Basic consolidation process
In coarse soils (sands & gravels) any volume change resulting from a change in loading occurs immediately; increases in pore pressures are dissipated rapidly due to high permeability. This is called drained loading.
In fine soils (silts & clays) - with low permeabilities - the soil is undrained as the load is applied. Slow seepage occurs and the excess pore pressures dissipate slowly, consolidation settlement occurs.
So, consolidation settlement: is decrease in voids volume as pore-water is squeezed out of the soil. It is mostly significant in fine soil (clay & silt).

61. Consolidation settlement calculation
Laboratory Consolidation Test
Data obtained from laboratory testing can be used to predict consolidation settlement reasonably, but rate is often poorly estimated.
1-D field consolidation can be simulated in Laboratory.
Wide foundation
simulation of 1-D field consolidation in Lab GL
Sand or Drainage layer
porous stone
undisturbed soil specimen
Dia = mm
Height = mm
Saturated clay
lab
field

62. Consolidation settlement calculation
Laboratory Consolidation Test
Typical results of laboratory consolidation test
The study of the change in the void ratio of the specimen with pressure will allow us to find soil compressibility parameters.
What are soil compressibility parameters?
Effective pressure, s’ (log scale)
Typical plot of e against log s’
CE Foundation Engineering Settlement of shallow foundations

63. Consolidation settlement calculation
Soil compressibility parameters
For one-dimensional compression and swelling there are simple relationships between the void ratio, e, and the logarithm of the vertical effective stress, s ‘.
log ’
void ratio, e 1 Cs
Cc compression index 1 Cc
CC and Cs are slopes of the e–log s‘ plot
Cs : swell index
Note. Swell index (Cs) may be also called
re-compression index (Cr) Cs
or Cr

64. Consolidation settlement calculation
Soil compressibility parameters
These indexes are required for the calculation of field settlement caused by consolidation.
These indexes is best determined by the laboratory test results for void ratio, e, and pressure s’ (as shown above).
Several empirical expressions have been also suggested:
PI: Plasticity Index
LL: Liquid Limit
For undisturbed clays, Skempton (1944)
(Kulhawy and Mayne, 1990)
GS: Specific Gravity
e0 : in situ void ratio
For natural clays, Rendon-Herrero (1983)

65. Consolidation settlement calculation
Soil compressibility parameters
Compression and Swell Indexes of some Natural Soils
CE Foundation Engineering Settlement of shallow foundations

66. Consolidation settlement calculation
Normally Consolidated and Overconsolidated Clays
The upper part of the e –log s’ plot is somewhat curved with a flat slope, followed by a linear relationship having a steeper slope.
This is can be explained:
A soil in the field at some depth has been subjected to a certain maximum effective past pressure in its geologic history.
This maximum effective past pressure may be equal to or less than the existing effective overburden pressure at the time of sampling.
Normal Compression
Void ratio, e
Swelling re-compression
Effective pressure, s’ (log scale)
CE Foundation Engineering Settlement of shallow foundations

67. Consolidation settlement calculation
Normally Consolidated and Overconsolidated Clays
Casagrande (1936) suggested a simple graphic construction to determine the preconsolidation pressure s’c from the laboratory e–log s‘ plot.
In general the overconsolidation ratio (OCR) for a soil can be defined as:
Void ratio, e
where s ’ is the present effective vertical pressure.
If OCR > 1 overconsolidated soil
If OCR = 1 normally consolidated
s’c
Effective pressure, s’ (log scale)

68. Calculation of Primary Consolidation Settlement
Consolidation settlement calculation
Calculation of Primary Consolidation Settlement
Let us consider a saturated clay layer of initial thickness Ho (or H), where the average effective pressure increases, from s ’0 to s ’ 0 +Ds ’ causing consolidation settlement Sc= DH.
average vertical strain =
Saturated clay
Ground level (GL)
q kPa H
Time = 
e = eo - e Ho
Time = 0+
e = eo
s ’ 0
s ’ 0 + Ds ’
Macro-scale
Sand layer

69. Calculation of Primary Consolidation Settlement
Consolidation settlement calculation
Calculation of Primary Consolidation Settlement
Consider an element of soil where the volume of solid, Vs = 1 initially e 1 eo Vs
Micro-scale
Time = 0+
Time = 
average vertical strain =

70. Consolidation settlement calculation
Calculation of Primary Consolidation Settlement
Equating the two expressions for average vertical strain,
consolidation settlement
change in void ratio
initial thickness of clay layer
initial void ratio
as, Sc = DH
How to get the changes in void ratio De ?

71. Consolidation settlement calculation
Calculation of Primary Consolidation Settlement
For normally consolidated clay (s ’ 0 >s c’ ) 
OA or AD on the graph:
Thus,
where:
CC  is “Compression Index” obtained from the slope of the e–log s‘ plot. CC is soil parameter. c
s c’ = Preconsolidation pressure.
Note: is also called

72. Consolidation settlement calculation
Calculation of Primary Consolidation Settlement
For over-consolidated clay (s ’ 0 < s c’ )
There are two cases:
Case (1): when s ’ 0 +Ds ’ ≤ s c’
Case (2): when s ’ 0 +Ds ’ > s c’ c
s c’ = Preconsolidation pressure.
CE Foundation Engineering Settlement of shallow foundations

73. Consolidation settlement calculation
Calculation of Primary Consolidation Settlement
For over-consolidated clay (s ’ 0 < s c’ )
Case (1): when s ’ 0 +Ds ’ ≤ s c’
i.e. along the line BC on the laboratory rebound curve.
Thus,
Where CS is slope of rebound curve.
CS or Cr is soil parameter and called “Swell Index” or re-compression index. c
s c’ = Preconsolidation pressure.

74. Consolidation settlement calculation
Calculation of Primary Consolidation Settlement
For over-consolidated clay (s ’ 0 < s c’ )
Case (2): when s ’ 0 +Ds ’ > s c’
i.e. along the line BC then CD.
Thus,
CS = Swell Index or recompression index Cr
CC = Compression Index c
s c’ = Pre-consolidation pressure.

75. Consolidation settlement calculation
Calculation of Primary Consolidation Settlement
Example problem
A soil layer 3 m thick is consolidated under an effective vertical stress of 50 kPa at a void ratio of If the compression index Cc of the soil is 0.138, what is the settlement, when the effective vertical stress is increased to 100 kPa.
Key Solution
The consolidation settlement for a layer of thickness H can be represented by the compression index Cc defined by:
CE Foundation Engineering Settlement of shallow foundations

76. Consolidation settlement calculation
Example problem q
A soil profile is shown in the figure.
If a uniformly distributed load is applied at the ground surface, what will be the settlement of the clay layer caused by primary consolidation?
We are given that sc for the clay is 125 kN/m2 and Cs=1/6 Cc , where:
CE Foundation Engineering Settlement of shallow foundations

77. Consolidation settlement calculation
Solution
The important procedure for determining consolidation settlement is to calculate:
o‘ the initial effective pressure at the middle of compressible soil layer
 ‘ the average net effective stress increase in the compressible soil layer.
For wide uniformly distributed load, such as given in the question, the stress increase at any depth, z, can be given as:
 ‘ = q = 50 kPa
NOTE:
If the loaded area is limited (e.g. rectangular foundation) we will need to compute the stress increase  ‘ within the soil mass using Boussinesq method or other approach assuming elasticity.
CE Foundation Engineering Settlement of shallow foundations

78. Consolidation settlement calculation
Solution (cont..)
CE Foundation Engineering Settlement of shallow foundations

79. Consolidation settlement calculation
Solution (cont..)

80. Consolidation settlement calculation
Time rate of consolidation
You learned above how to calculate the ultimate settlement of primary consolidation Sc (at the end of consolidation).
However this settlement usually takes long time, much longer than the time of construction.
And we may need to know the settlement at a specific time.
End of Construction
End of primary consolidation
Time, t
Settlement, S(time)
CE Foundation Engineering Settlement of shallow foundations

81. Consolidation settlement calculation
Time rate of consolidation
Permeable layer
Hdr H
Clay
Hdr
Hdr
U = the degree of consolidation
Cv is obtained from laboratory testing

82. Consolidation settlement calculation
Secondary Consolidation Settlement
In some soils (especially recent organic soils) the compression continues under constant loading after all of the excess pore pressure has dissipated, i.e. after primary consolidation has ceased.
This is called secondary compression or creep, and it is due to plastic adjustment of soil fabrics.
This settlement can be calculated using the secondary compression index, Ca.
The Log-Time plot (of the consolidation test) can be used to estimate the coefficient of secondary compression Ca.
void ratio, e ep De t1 t2
CE Geotechnical Engineering II Compressibility of Soil

83. Consolidation settlement calculation
Secondary Consolidation Settlement
The magnitude of the secondary consolidation can be calculated as:
where:
void ratio, e
ep void ratio at the end of primary consolidation.
H thickness of clay layer. ep De
The general magnitudes of Ca is observed to correlate with Cc as follows: t1 t2

84. Field test (Bearing capacity with settlement consideration)
Plate load test
Standard Penetration Test (SPT)
Cone Penetration Test (CPT)
Three Ws  three dimensions to find a space
CE Foundation Engineering Settlement of shallow foundations

85. Field test (Bearing capacity with settlement consideration)
Plate load test
Plate Load Test is a field test for determining the ultimate bearing capacity of soil and the likely settlement under a given load (ASTM D ).
The Plate Load Test basically consists of loading a steel plate placed at the foundation level and recording the settlements corresponding to each load increment.

86. Field test (Bearing capacity with settlement consideration)
Plate load test
BF = width of the proposed foundation Bp = width of test plate Sp= settlement of test plate for a given intensity of load, q SF = settlement of the foundation for a given intensity of load, q

87. Field test (Bearing capacity with settlement consideration)
Standard Penetration Test (SPT)
Bearing Capacity for sandy soil can be based on SPT N value and settlement consideration.
Meyerhof (1956) proposed a correlation for the net allowable bearing pressure for foundations with the standard penetration resistance, N60.

88. Field test (Bearing capacity with settlement consideration)
Standard Penetration Test (SPT)
Bearing Capacity for sandy soil can be based on CPT value and tolerable settlement.
Meyerhof (1956) proposed a correlation for the net allowable bearing pressure for foundations with the cone resistance, qc .
CE Foundation Engineering Settlement of shallow foundations

89. CE 483 - Foundation Engineering - 5. Settlement of shallow foundations
References
Braja M Das, 2011, Principles of Foundation Engineering, 7th ed, Chapter- 5.
Previous course materials and presentations at KSU.
Geotechnical on the web:
Andrew Bond and Andrew Harris, 2008, Decoding Eurocode 7, London.
The Institution of Structural Engineers library:
CE Foundation Engineering Settlement of shallow foundations