Input parameters pane specifies the dimensions, properties of the pile, soil, and load cases. These are entered in their respective tabs.
Pile Dimensions tab defines the pile type, crosssection of the pile and the dimensions of the pile for the foundation. It also displays a pictorial view of the pile along with the layers of soil.
Select the pile type (method of construction) used for the project in the pile dimensions tab. The choices for pile types are
a) Driven
b) Bored (Bored castinsitu)
c) CFA (Continuous flight auger)
d) Driven Castinsitu
The method of construction along with the pile crosssection and pile material is used to determine the default values for 'k earth pressure coefficient' for sand layers. It is also used in calculation of pile capacity estimation.
Table 1 below describes the practical choices for pile method of construction, pile crosssection and material used. The application may give warnings (which may be ignored by the user) if the selections don’t adhere to the table below.
Table 1 Pile type, crosssection, material compatibility matrix
Pile Type 
Driven 
Bored 
CFA 
Driven Castinsitu 

Pile Crosssection 
Hollow Circular HSection 
Square Rectangular Hollow Circular 
Full Circular 
Full Circular 
Full Circular 
Construction material 
Steel 
Concrete 
Concrete 
Concrete 
Concrete 
Select the pile crosssection to be used for the project in the pile dimensions tab. The choices for pile crosssection are
a) Full circular pile
b) Square pile
c) Rectangular pile
d) Hollow circular pile
e) H Section pile
Based on the crosssection of the pile, define the parameters of the pile in the adjacent pile dimensions pane.
The application may give warnings (which may be ignored by user) if the selections don’t adhere to the Table 1 Pile type, crosssection, material compatibility matrix described in 'Pile Type' section.
Table 2 Summary of parameters to be specified for the different pile cross sections.

Full Circular pile 
Square pile 
Rectangular pile 
Hollow Circular pile 
H Section pile 
Pile length 
✓ 
✓ 
✓ 
✓ 
✓ 
Pile length above ground 
Optional 
Optional 
Optional 
Optional 
Optional 
Number of elements 
✓ 
✓ 
✓ 
✓ 
✓ 
Pile diameter 
✓ 


✓ 

Diameter of base 
Optional 




Pile wall thickness 



✓ 

Sectional breadth 

✓ 
✓ 

✓ 
Sectional depth 


✓ 

✓ 
Sectional area 




✓ 
Moment of inertia about xaxis 




✓ 
Moment of inertia about yaxis 




✓ 
Direction of loading 


✓ 

✓ 
Specify the pile length here in the units chosen. After selecting the pile crosssection, this should be the first item to be entered on this page. This field is mandatory for all pile crosssections.
Note: For TRIAL version, Pile length is restricted to 6m (19.6ft)
Specify the length of the pile length above the ground here in the units chosen. This field is optional and applicable for all pile crosssections.
This is the guidance of number of elements used in the finite element calculation. The program may adjust this number based on the other input data to carry out the analysis. A higher number of elements will improve granularity but may result in some loss of fidelity. The default value of 50 elements is recommended.
Use the slider to select the number of elements. A minimum of 20 elements and a maximum of 100 elements are permitted. This field is applicable for all pile crosssections.
Specify the external diameter of the pile here in the units specified. This field is mandatory for Full circular pile and Hollow Circular Pile.
Specify the diameter of base of the pile here in the units specified if different from the pile diameter. This is usually required for piles with enlarged bases. This field is optional and can be specified only for full circular pile.
Specify the pile wall thickness of the pile in the units specified. This field is mandatory and applicable for hollow circular pile.
Specify the sectional breadth the pile here in the units specified. This field is mandatory for Square pile, Rectangular pile and H Section pile.
Specify the sectional depth the pile here in the units specified. This field is mandatory for Rectangular pile and H Section Pile.
Square Pile 
Rectangular Pile 
H Section Pile 
Specify the sectional area the pile here in the units specified. This field is mandatory for H Section pile. The default value displayed here is calculated for a Hsection pile with a 1” thickness.
Use the radio button to select the direction of loading of the pile. The choices are xaxis and yaxis. This field is applicable only for Rectangular pile and HSection piles. The default value is taken as xaxis. The diagram below shows the axis conventions used. The direction of loading will also reflect in the loading diagrams.
Rectangular Pile 
H Section Pile 

Specify the moment of inertia of the pile about Xaxis here in the units specified. This field is mandatory for H Section Pile.
Specify the moment of inertia of the pile in Yaxis here in the units specified. This field is mandatory for H Section Pile.
The pile diagram displays the pile along with all the layers of soil. Different scales are used for the depth axis and horizontal axis. The pile length in the diagram is 20 m. This diagram shows the perspective view of the pile along with the different layers of soil, scour and depth of water table.
Pile properties tab is used for specifying the properties of the pile material, pile head boundary conditions, selfweight inputs.
Use the dropdown menu to select the material used for the pile. The elastic modulus of the pile along with the unit weight is updated based on the selection.
Table 3 Elastic modulus of pile
Pile Material 
Elastic Modulus 

(kN/m^{3}) 
(kips/ft^{3)} 

Steel 


ASTMA36 
2.0*10^{8} 
4.173 * 10^{6} 
Concrete 


M20 
3.0 * 10^{7} 
6.26 * 10^{5} 
M25 
3.1 * 10^{7} 
6.47 * 10^{5} 
M30 
3.3 * 10^{7} 
6.68 * 10^{5} 
M35 
3.4 * 10^{7} 
7.10 * 10^{5} 
M40 
3.5 * 10^{7} 
7.31 * 10^{5} 
M45 
3.6 * 10^{7} 
7.52 * 10^{5} 
M50 
3.7 * 10^{7} 
7.73 * 10^{5} 
Select the “User Defined” option to enter values for the elastic modulus and unit weight of the pile material.
The elastic modulus of pile is shown here based on the material specified. If “User Defined” material is selected, the elastic modulus of the pile can be edited and entered here.
The unit weight of pile material of pile is shown here based on the material specified. If “User Defined” material is selected, the ‘unit weight of material’ can be edited and entered here.
The selfweight properties could be taken into account for axial analysis of the pile. The values of selfweight are autocalculated based on the pile dimensions and soil properties or they could be userdefined.
The automatically calculated ‘Effective pile weight’ is shown here as default value. Effective pile weight accounts for the reduction in pile weight due to buoyancy effect of water. This will be used for ‘selfweight’ analysis if required. To enter a user defined value of ‘effective pile weight’, select the checkbox adjacent to this and enter the user defined value in the ‘text field’ next to it.
The automatically calculated plug weight is shown here. The automatic calculation is based on the different soil layers and the inner diameter of the bottom segment of the pile. This is only relevant for driven hollow piles. A 0.9 reduction factor is used in calculating the plug weight. This will be used for ‘selfweight’ analysis if required. To enter a user defined value of plugweight, select the checkbox adjacent to this and enter the user defined values in the ‘text field’ next to it.
The boundary conditions pertain to only for lateral analysis of pile and are applied at the pile head.
Select the checkbox ‘Lateral displacement’ to set the lateral ‘pile head’ displacement. Enter the lateral displacement value in the field provided.
Note: Lateral displacement can be specified only if there are no lateral loads applied at the pile head. This also includes distributed lateral loads starting at the pile head.
Select the checkbox ‘Rotation’ to set the ‘pile head’ rotation. Enter the rotation value (radians) in the field provided.
Note: Rotation can be specified only if there are no lateral moments applied at the pile head.
Select the checkbox ‘Rotational spring’ to set the ‘pile head’ rotational spring value. Enter the rotational spring value in the field provided.
Soil properties tab is used to enter the details of soil layers, and standard penetration test (SPT) data. The tab is further subdivided into 2 tabs (on right hand side)
· SPT
Soil Properties Tab is used to enter the data about the site condition, subsoil layers and properties of each soil layer. It is divided into 3 panes
This tab is mandatory for ‘Pile Capacity Estimation’, ‘Laterally Loaded Pile Analysis’ and ‘Axially Loaded Pile Analysis’.
This field is not mandatory. Specify the local scour around the pile at the site. Enter the ‘scour’ value in the field.
Some restrictions on the scour depth:
· Scour depth can extend up to the first three layers of soil
· Scour depth should be less than 2.5 times of diameter of the pile
· Scour cannot extend into a rock layer.
This field is not mandatory. Specify the depth of water table at the site in the field provided.
If no value is specified, it is assumed the water table lies below all the layers of soil specified. For water table at ground level, set it as 0.
Specify the value of ‘zeta (z)’ in the field provided.
Zeta (z) is required for Axial load analysis by ‘Elastic method’ and is based on the parameter proposed by (Randolph and Wroth 1978) as where r_{m} is the radial extent of the influenced zone in the soil layer due to axil load and r_{o} is the radius of the pile.
Min value: 3
Max value: 5
Default value: 4
Specify the value of ‘Critical depth ratio’ (z_{c}/d) in the field provided.
Zc is the ratio of depth to diameter of pile beyond which the vertical and lateral effective stresses are considered to remain constant up to the pile base. The usual values are Zc = 15 for loose sand and 20 for dense sand.
Critical depth ratio’ is required for Pile capacity estimation in ‘Sand soil’ when the limiting side friction and base resistance are determined by the values computed at the critical depth. This method is followed in IS2911 (IS 2911 Design and construction of pile foundations  Code of Practice (Part 1. Sections  1,2&3) 2010). The software also adopts this method for limiting base resistance determined by ‘Nq  Berezantev – Zc’ method. The table below summarizes the scenarios under which Zc is required.
Analysis Module:
a) Pile capacity analysis
b) Axially loaded pile analysis
Table 4 Scenarios where ‘critical depth ratio’ is required

Method for maximum base resistance 

N_{q}  q_{lim} method (API2011, API2000) 
N_{q}Z_{c} method (IS2911) 
N_{q} Berezantev  Z_{c} method 
Meyerhoff SPT method (IS2911) 
Meyerhoff SPT method for silty sand (IS2911) 

Method for maximum side friction 
β method (API2011) 

✓ 
✓ 


K  δ method (API2000) 

✓ 
✓ 



K  δ  Z_{c} method (IS2911) 
✓ 
✓ 
✓ 
✓ 
✓ 

Meyerhoff SPT method (IS2911) 

✓ 
✓ 



Meyerhoff SPT method for silty sand (IS2911) 

✓ 
✓ 


Min value: 15
Max value: 20
Default value: 15
Specify the unit weight of water in the field provided. This parameter is a mandatory field.
Min value: 9.5 kN/m^{3} or 0.062 kips/ft^{3}
Max value: 10.5 kN/m^{3} or 0.067 kips/ft^{3}
Default value: 9.8 kN/m^{3} or 0.063 kips/ft^{3}
The ‘Soil Layer Table’ is used to define the type of soil and the thickness of each layer of soil. The properties of the soil layer selected is entered in the adjacent ‘Soil Layer Properties’ pane.
Number of soil layers
First select the number of soil layers using the up/down arrow. This will set the number of rows in the table to populate
Up 50 soil layers can be specified.
Note: For TRIAL version, number of soil layers is restricted to 3.
Table: Doubleclick on the table cells to edit the content of the cells.
The table consists of four columns – Layer, Soil type, Starting depth and Layer thickness. The ‘Layer’ column and the ‘Starting depth’ columns cannot be edited.
To enter the Soil type, click on the cell in this column and select the type of soil from the ‘drop down’ menu for each segment.
Permissible soil types currently are – Soft Clay, Stiff Clay, Sand, Weak Rock, and Hard Rock.
You can use ‘Sand’ to represent silt, silty sand, and gravel as well.
Layer thickness Column – This defines the thickness of each layer of soil.
Starting depth Column – This column is auto calculated based on the thickness of soil layers entered.
The pile diagram in the pile dimensions tab will graphically show the values entered in this table.
Note: Soil layers should extend up to pile depth below ground + n * effective diameter
n = 3 for pile terminating in soil
n = 1 for pile terminating in rock.
Select a layer in the ‘Soil layer table’ to display the soil properties associated with it in this pane.
Note: Mandatory fields have a () adjacent to them depending on the choices made for capacity estimation, axial pile analysis and lateral pile analysis.
Note: The soil layer properties need to be arrived at from the soil investigation report. The application populates median recommended values for each property. These values need to be updated with actual values from the soil investigation report or values chosen by the user.
Soil type: Shows the type of soil in this layer. (Field cannot be edited)
Unit weight of soil (γ): The unit weight to be given as data is the total unit weight of soil in the layer that is the moist unit weight above the water table and saturated unit weight below the water table. If required one may choose to divide the layer in to two halves one above water table and the other below the water table having different unit weights.
Starting depth: Displays the starting depth of the layer. (Field cannot be edited)
Layer thickness: Displays the thickness of the selected layer. (Field cannot be edited)
Method for maximum side friction: The table below details the options available for Soft Clay and Stiff Clay soil.
Table 5 Details of ‘Method for maximum side friction’ for clay soil
Method for maximum side friction 
Notes 
API2011 
(API 2011 Geotechnical and Foundation Design Considerations April 2011, Addendum 1, 2014) 
a method (IS2911) 
(IS 2911 Design and construction of pile foundations  Code of Practice (Part 1. Sections  1,2&3) 2010) 
Semple & Ridgen (1984) 
(Semple and Rigden 1984) 
Kolk & Van Der Velde (1996) 
(Kolk and van der Velde 1996) 
The maximum unit shaft friction of clay soil layers is based on the equation
Where α is a multiplier and is the undrained cohesion of the soil. Methods of estimating the α multiplier by the following four methods are available in the software:
1) API RP GEO 2011
In this
2) α method (IS 2911)
Curve relating the given in the Standard is made use of.
3) Semple & Rigden (1984)
4) Kolk& van der Velde (1996)
The unit base resistance is given by
Method for maximum side friction: Select the method for maximum side friction from the dropdown list. This parameter is mandatory for Axial pile capacity calculation and Axial loaded pile analysis.
Table 6 Details of ‘Method for maximum side friction’ for soft clay soil
Method for maximum side friction 
Notes 
API2011 
(API 2011 Geotechnical and Foundation Design Considerations April 2011, Addendum 1, 2014) 
a method (IS2911) 
(IS 2911 Design and construction of pile foundations  Code of Practice (Part 1. Sections  1,2&3) 2010) 
Semple & Ridgen (1984) 
(Semple and Rigden 1984) 
Kolk & Van Der Velde (1996) 
(Kolk and van der Velde 1996) 
For more details on the methods, refer to the section on 'Method for maximum side friction' under 'Clay Soil'.
Table 7 Required properties for ‘pile capacity estimation’ for soft clay soil.
Method for maximum side friction 
Cohesion at top 
Cohesion at bottom 
API2011 
✓ 
✓ 
α method (IS2911) 
✓ 
✓ 
Semple Rigden 
✓ 
✓ 
Kolk & Van der Velde 
✓ 
✓ 
Axial analysis method: Select the ‘Axial analysis method’ using the ‘drop down menu’ for axial load analysis.
Table 8 Axial analysis method details for Soft Clay
Axial analysis method 
Method details 
API2000 
(API 2000 RP2AWSD 2000) 
API2011 
(API 2011 Geotechnical and Foundation Design Considerations April 2011, Addendum 1, 2014) 
Elastic method 
Based on elastic properties of soil. 
Table 9 Required properties for ‘axial pile analysis’ for soft clay soil.
Axial analysis method 
Cohesion at top 
Cohesion at bottom 
R factor 
Elastic modulus 
Poisson ratio 
API2011 
✓ 
✓ 
✓ 

API2000 
✓ 
✓ 
✓ 

Elastic Code 
✓ 
✓ 
✓ 
✓ 
Lateral analysis method: Select the ‘Lateral analysis method’ using the ‘drop down menu’ for lateral load analysis.
Table 10 Lateral analysis method details for Soft Clay
Lateral analysis method 
Method details 
API2011 
(API 2000 RP2AWSD 2000) 
k_{h} Based Horizontal Subgrade Modulus 
Lateral spring of constant stiffness based on k_{h} _{ } IS2911 recommends use of k_{h} based horizontal subgrade modulus method for lateral analysis of pile. (IS 2911 Design and construction of pile foundations  Code of Practice (Part 1. Sections  1,2&3) 2010) 
n_{h} Based Horizontal Subgrade Modulus Variation 
Lateral spring of stiffness proportional to depth based on n_{h} _{ } IS2911 recommends use of n_{h} based horizontal subgrade modulus variation method for lateral analysis of pile. (IS 2911 Design and construction of pile foundations  Code of Practice (Part 1. Sections  1,2&3) 2010) 
1. API 2011 recommends nonlinear py models for static and cyclic loading. .The parameters used in the model are undrained cohesion c_{u}, ε_{50}_{ }strain at 50% maximum lateral stress p_{u} and a factor J.
2. k_{h} based method on Horizontal Subgrade Modulus
IS 2911 has provided recommended values for use in this method
3. Linear elastic spring model based on n_{h}.
In this approach the lateral soil resistance is proportional to depth given by p/y = n_{h} x z where z is the depth.
Recommended values of n_{h} (Davisson 1970) are :
Soft normallyconsolidated clays: 350 to700 kN/m^{3}
Soft organic silts: 150kN/^{ }m^{3}. The input required for this method is the value of n_{h} for the soil layer.
IS2911 has provided recommended values for use in this method
Table 11 Required properties for lateral pile analysis for soft clay soil.
Lateral analysis method 
Cohesion at top 
Cohesion at bottom 
J constant 
ε 50 
Horizontal subgrade modulus 
Linear variable subgrade modulus 
API2011 
✓ 
✓ 
✓ 
✓ 


k_{h} Based Horizontal Subgrade Modulus 




✓ 

n_{h} Based Horizontal Subgrade Modulus Variation 





✓ 
Table 12 Soil property details for soft clay soil
Soil property 
Units 
Min value 
Max value 
Notes 
Elastic modulus of soil 
kN/m^{2} 
1750 
5000 

kips/ft^{2} 
36.54 
104.4 

Poisson Ratio 

0.1 
0.5 
Default value: 0.5 
Cohesion at top 
kN/m^{2} 
0 
100 
Value of 0 is only permissible for the first soil layer. 
kips/ft^{2} 
0 
2.09 

Cohesion at bottom 
kN/m^{2} 
> 0 
100 

kips/ft^{2} 
> 0 
2.09 

J Constant 

0.25 
0.5 
Default value: 0.5 
e 50 

> 0 
0.025 
Default value: 0.01 
R factor 

0.5 
1.0 
Default value: 0.9 
Horizontal subgrade modulus 
kN/m^{3} 
> 500 


kips/ft^{3} 
> 10 


Horizontal subgrade modulus variation 
kN/m^{3} 
> 10 
1000 

kips/ft^{3} 
> 0.25 
21 
Method for maximum side friction: Select the method for maximum side friction from the dropdown list. This parameter is mandatory for Axial pile capacity calculation and Axial loaded pile analysis.
Table 13 Details of ‘Method for maximum side friction’ for stiff clay soil
Method for maximum side friction 
Notes 
API2011 
(API 2011 Geotechnical and Foundation Design Considerations April 2011, Addendum 1, 2014) 
a method (IS2911) 
(IS 2911 Design and construction of pile foundations  Code of Practice (Part 1. Sections  1,2&3) 2010) 
Semple & Ridgen (1984) 
(Semple and Rigden 1984) 
Kolk & Van Der Velde (1996) 
(Kolk and van der Velde 1996) 
For more details, refer to the section on 'Method for maximum side friction' under 'Clay Soil'.
Table 14 Required properties for ‘pile capacity estimation’ for stiff clay soil.
Method for maximum side friction 
Cohesion at top 
Cohesion at bottom 
API2011 
✓ 
✓ 
α method (IS2911) 
✓ 
✓ 
Semple Rigden 
✓ 
✓ 
Kolk & Van der Velde 
✓ 
✓ 
Axial analysis method: Select the ‘Axial analysis method’ using the ‘drop down menu’ for axial load analysis.
Table 15 Axial analysis method details for stiff clay
Axial analysis method 
Method details 
API2000 
(API 2000 RP2AWSD 2000) 
API2011 
(API 2011 Geotechnical and Foundation Design Considerations April 2011, Addendum 1, 2014) 
Elastic method 
Based on elastic properties of soil. 
Table 16 Required properties for ‘axial pile analysis’ for stiff clay soil.
Axial analysis method 
Cohesion at top 
Cohesion at bottom 
R factor 
Elastic modulus 
Poisson ratio 
API2011 
✓ 
✓ 
✓ 

API2000 
✓ 
✓ 
✓ 

Elastic Code 
✓ 
✓ 
✓ 
✓ 
Lateral analysis method: Select the ‘Lateral analysis method’ using the ‘drop down menu’ for lateral load analysis.
Table 17 Lateral analysis method details for stiff clay
Lateral analysis method 
Method details 
API2011 
(API 2011 Geotechnical and Foundation Design Considerations April 2011, Addendum 1, 2014) 
REESE 
(Reese and Cox, Field Testing and Analysis of Laterally Loaded Piles in Stiff Clay April 1975) 
k_{h} Based Horizontal Subgrade Modulus 
Lateral spring of constant stiffness based on k_{h}
IS2911 recommends use of k_{h} based horizontal subgrade modulus method for lateral analysis of pile. (IS 2911 Design and construction of pile foundations  Code of Practice (Part 1. Sections  1,2&3) 2010) 
1. API2011 recommends nonlinear py models for static and cyclic loading. The parameters used in the model are undrained cohesion c_{u}, ε_{50 }strain at 50% maximum lateral stress p_{u } and a factor J.
2. Reese model
This is also a nonlinear py model for static and cyclic loading (Reese,Cox,Koop1975). The soil parameters needed are c_{u}, e_{50 }strain at 50% maximum lateral stress p_{u }.The model is applicable to only layers below water table.
3. Method based on horizontal subgrade modulus k_{h} of the soil layer.
This is a linear spring model and the k_{h} should include the correction ( division by 1.5) for use in piles. In SI units the value should be for 1m x 1m and in American units for 1ft x 1ft of pile The values k_{h} recommended by Terzaghi (1955) for pile width are given Table 18 & Table 19 below.
Table 18 k_{h} values for 1ft width & 1ft length of pile (Terzaghi, 1955)
Consistency 
Stiff 
Very stiff 
Hard 
q_{u}(tsf) 
1 2 
24 
>4 
K_{h}(tcf) 
50 
100 
>200 
The values in SI units after width correction for 1m are given below:
Table 19 Modified Terzaghi values of k_{h} for 1 m width & 1m length of pile in SI units
Consistency 
Stiff 
Very stiff 
Hard 
q_{u }(kPa) 
100200 
200400 
>400 
k_{h}(kN/m^{3}) 
5300 
10500 
>21000 
IS2911 also has given recommendations for values.
Modified Vesic’s equation for piles (Bowels 1968)
Table 20 Required properties for laterally loaded pile analysis for stiff clay soil
Lateral analysis method 
Cohesion at top 
Cohesion at bottom 
J constant 
ε 50 
Horizontal subgrade modulus 
API2011 
✓ 
✓ 
✓ 
✓ 

REESE 
✓ 
✓ 

✓ 

k_{h} based Horizontal Subgrade Modulus 




✓ 
Table 21 Soil property details for stiff clay soil
Soil property 
Units 
Min value 
Max value 
Notes 
Elastic modulus of soil 
kN/m^{2} 
4000 
10000 

kips/ft^{2} 
83.5 
208.8 

Poisson Ratio 

0.1 
0.5 
Recommended value Below water table: 0.5 Above water table: 0.4 
Cohesion at top 
kN/m^{2} 
100 

For the top layer, a value from 0 can be used. 
kips/ft^{2} 
2.09 


Cohesion at bottom 
kN/m^{2} 
100 


kips/ft^{2} 
2.09 


J Constant 

0.25 
0.5 
Default value: 0.25 
e 50 

> 0 
0.025 
Default value: 0.005 
R factor 

0.5 
1.0 
Default value: 0.9 
Horizontal subgrade modulus 
kN/m^{3} 
> 1000 


kips/ft^{3} 
> 21 

Method for maximum side friction: Select the method for maximum side friction from the dropdown list. This parameter is mandatory for Pile capacity estimation calculation and Axial loaded pile analysis. The table below details the options available for Sand soil.
Table 22 Details of ‘Method for maximum side friction’ for sand
Method for maximum side friction 
Notes 
β method (API2011) 
(API 2011 Geotechnical and Foundation Design Considerations April 2011, Addendum 1, 2014) 
K  δ method (API2000) 
(API 2000 RP2AWSD 2000) 
K  δ  Zc method (IS2911) 
(IS 2911 Design and construction of pile foundations  Code of Practice (Part 1. Sections  1,2&3) 2010) 
Meyerhoff SPT method (IS2911) 
(IS 2911 Design and construction of pile foundations  Code of Practice (Part 1. Sections  1,2&3) 2010) 
Meyerhoff SPT method for silty sand (IS2911) 
(IS 2911 Design and construction of pile foundations  Code of Practice (Part 1. Sections  1,2&3) 2010) 
1) The β  f_{max} method (API2011)
In this method is given by the equation in which β depends on the density of the sand layer and p_{v}’ is the vertical effective stress. β values recommended by API range from 0.29 for medium dense sand to 0.56 for very dense sand. User defined value β could also be specified. This method requires also a value of f_{lim} which is the limiting value for t_{max}. API proposes flim values ranging from 67 kPa for medium dense sand to 115 kPa for very dense sand. User defined value of flim could also be prescribed.
2) K  δ  f_{lim} method (API2000)
In this method is given by the equation in which K is lateral earth pressure coefficient, is the angle of friction between the pile surface and soil and is the vertical effective stress. The values of K and δ need to be specified by the user after due consideration of type of soil, pile and method of installation. Some guidance values in this regard are given in the appendix. API recommends a K value of 0.8 for open ended pipe piles and 1.0 for closed ended piles. The recommended δ values range from 15 degrees for very loose sand to 35 degrees for very dense sand. Standards and literature would be of help in choosing the appropriate values of K and δ. K and δ displayed in the software are those recommended by the code for driven tubular piles.
3) K  δ  Z_{c} method (IS 2911)
In this method is given by the equation .The maximum vertical effective stress is limited to the value at the critical depth Z_{c}. Z_{c} /D ratio is specified ranging from 15 for φ’ to 20 for φ’. There is provision for user defined values of δ, K and Z_{c}
4) Meyerhoff SPT method (IS 2911)
In this method for sand and for silty sand where is the average N value for the layer.
Table 23 Required properties for ’Pile Capacity Estimation’  ‘method for maximum side friction’ for sand
Method for maximum side friction 
Friction angle 
Shaft friction factor (β) 
Angle of shaft friction (δ) 
K Earth pressure coefficient 
Limiting shaft friction (flim) 
Standard penetration test, average value in layer 
Elastic modulus 
Poisson ratio 
β method (API2011) 
✓ 
✓ 




K  δ method (API2000) 
✓ 
✓ 
✓ 




K  δ  Z_{c} method (IS2911) 
✓ 

✓ 
✓ 




Meyerhoff SPT method (IS2911) 
✓ 



Meyerhoff SPT method for silty sand (IS2911) 
✓ 


Method for maximum base resistance: Select the method for maximum base resistance from the dropdown list. This parameter is mandatory for Pile capacity estimation and Axially loaded pile analysis. The table below details the options available for Sand soil.
Table 24 Details of 'Method for maximum base resistance' for sand
Method for maximum base resistance 
Notes 
N_{q } q_{lim} method (API2011, API2000) 
(API 2000 RP2AWSD 2000) (API 2011 Geotechnical and Foundation Design Considerations April 2011, Addendum 1, 2014) 
N_{q}  Z_{c} method (IS2911) 
(IS 2911 Design and construction of pile foundations  Code of Practice (Part 1. Sections  1,2&3) 2010) 
N_{q}  Berezantsev  Z_{c} method 

Meyerhoff SPT method (IS2911) 
(IS 2911 Design and construction of pile foundations  Code of Practice (Part 1. Sections  1,2&3) 2010) 
Meyerhoff SPT method for silty sand (IS2911) 
(IS 2911 Design and construction of pile foundations  Code of Practice (Part 1. Sections  1,2&3) 2010) 
1) N_{q}  q_{lim} method. (API2011, API2000)
In API recommended values of N_{q} and q_{lim} are automatically displayed in the software. User may also specify values of N_{q} and q_{lim}
2) N_{q}  Zc method (IS 2911)
In this method the software automatically gets the value of N_{q} for the φ value from the curve given in IS 2911. This value is used together with the specified value of Zc/D ratio to get the limiting value of q_{max}. A default value of Zc/D = 15 is used for in the software. The user has option to prescribe other value of Zc/D up to 20.
3) Nq – Berezantsev  Zc method
In this method Nq is obtained from Berezantsev’s curve using the value of φ specified. This value is used together with the limiting value of qmax using the value of Zc/D specified.
4) Meyerhoff  SPT method (IS 2911)
In this method where is the average N value at the pile tip. Lb is the pile penetration in this embedment layer and D is the pile diameter. is limited to to 400 . In silty sand and is limited to 300N.
Note on average N Value:
For pile capacity estimation at various depths: Average N value at a given depth is computed using N values between 2D to +3D. If no SPT points are present in this range then the average or weighted average of the two closest points around this depth will be used. If only one SPT point is present in the entire sand layer, then the N value of this point will be used for the entire layer.
For pile capacity at the pile tip: For calculating Average N value at the pile tip, only points in the range of 2D to +3D will be used. If no points are present in this range then validation will fail.
Table 25 Required properties for ‘Pile Capacity Estimation’  ‘method for maximum base resistance’ for sand
Method for maximum base resistance 
Friction angle (f) 
Limiting end bearing (q_{lim}) 
Bearing capacity factor (N_{q}) 
Standard penetration test, value at pile base 
N_{q}  q_{lim} method (API2011, API2000) 
✓ 
✓ 


N_{q}  Z_{c} method (IS2911) 
✓ 


N_{q}  Berezantev  Z_{c} method 
✓ 



Meyerhoff SPT method (IS2911) 
✓ 

Meyerhoff SPT method for silty sand (IS2911) 
✓ 
Axial analysis method: Select the ‘Axial analysis method’ using the ‘drop down menu’ for axial load analysis.
Table 26 Axial analysis method details for sand
Axial analysis method 
Method details 
API2000 
(API 2000 RP2AWSD 2000) 
API2011 
(API 2011 Geotechnical and Foundation Design Considerations April 2011, Addendum 1, 2014) 
Elastic method 
Based on elastic properties of soil. 
Table 27 Required properties for ‘Axially loaded pile analysis’ and ‘method for maximum side friction’ for sand
Axial analysis method 
Method for maximum side friction 
Friction angle (f) 
Shaft friction factor (β) 
Angle of shaft friction (δ) 
K Earth pressure coefficient 
Limiting shaft friction (flim) 
Standard penetration test, average value in layer 
Elastic modulus 
Poisson ratio 
API2011 
β method (API2011) 
✓ 
✓ 




K  δ method (API2000) 
✓ 
✓ 
✓ 




K  δ  Z_{c} method (IS2911) 
✓ 

✓ 
✓ 





Meyerhoff SPT method (IS2911) 
✓ 



Meyerhoff SPT method for silty sand (IS2911) 
✓ 



API2000 
β method (API2011) 
✓ 
✓ 




K  δ method (API2000) 


✓ 
✓ 
✓ 




K  δ  Z_{c} method (IS2911) 
✓ 
✓ 
✓ 




Meyerhoff SPT method (IS2911) 
✓ 



Meyerhoff SPT method for silty sand (IS2911) 
✓ 



Elastic Code 
β method (API2011) 
✓ 
✓ 

✓ 
✓ 

K  δ method (API2000) 


✓ 
✓ 
✓ 

✓ 
✓ 

K  δ  Z_{c} method (IS2911) 
✓ 
✓ 
✓ 

✓ 
✓ 

Meyerhoff SPT method (IS2911) 
✓ 
✓ 
✓ 

Meyerhoff SPT method for silty sand (IS2911) 
✓ 
✓ 
✓ 
Table 28 Required properties for ‘Axially loaded pile analysis’ and ‘maximum base resistance’ for sand
Axial analysis method 
Method for maximum base resistance 
Friction angle (f) 
Limiting end bearing (q_{lim}) 
Bearing capacity factor (N_{Q}) 
Standard penetration test, value at pile base 
Elastic modulus 
Poisson ratio 
API2011 
N_{q}  q_{lim} method (API2011, API2000) 
✓ 
✓ 




N_{q}  Z_{c} method (IS2911) 
✓ 




N_{q}  Berezantev  Z_{c} method 
✓ 






Meyerhoff SPT method (IS2911) 
✓ 



Meyerhoff SPT method for silty sand (IS2911) 
✓ 



API2000 
N_{q}  q_{lim} method (API2011, API2000) 
✓ 
✓ 




N_{q}  Z_{c} method (IS2911) 
✓ 






N_{q}  Berezantev  Z_{c} method 
✓ 




Meyerhoff SPT method (IS2911) 
✓ 



Meyerhoff SPT method for silty sand (IS2911) 
✓ 



Elastic Code 
N_{q}  q_{lim} method (API2011, API2000) 
✓ 
✓ 

✓ 
✓ 

N_{q}  Z_{c} method (IS2911) 
✓ 



✓ 
✓ 

N_{q}  Berezantev  Z_{c} method 
✓ 

✓ 
✓ 

Meyerhoff SPT method (IS2911) 
✓ 
✓ 
✓ 

Meyerhoff SPT method for silty sand (IS2911) 
✓ 
✓ 
✓ 
Lateral analysis method: Select the ‘Lateral analysis method’ using the ‘drop down menu’ for lateral load analysis. The table below details the ‘Lateral analysis methods’ for the various soil types. Only the relevant recommended practices are displayed based on the soil type selected in the layer.
Table 29 Lateral analysis method details for sand
Lateral analysis method 
Method details 
API2011 
(API 2011 Geotechnical and Foundation Design Considerations April 2011, Addendum 1, 2014) 
n_{h} Based Horizontal Subgrade Modulus Variation 
Lateral spring of stiffness proportional to depth based on n_{h}
IS2911 recommends use of n_{h} based horizontal subgrade modulus variation method for lateral analysis of pile for sand layers. (IS 2911 Design and construction of pile foundations  Code of Practice (Part 1. Sections  1,2&3) 2010) 
Hybrid model for liquefied sand (Based on φ)

This model is based on the paper (Franke and Kyle 2013). This model makes use of the friction angle (φ) of layer

Hybrid model for liquefied sand (based on SPT)

This model is based on the paper (Franke and Kyle 2013). This model makes use of the average SPT of the layer.

1) API2011
Recommends a nonlinear py model for static and cyclic loading. The parameters needed are angle of internal friction φ and the value horizontal subgrade modulus. If not provided by the use the subgrade modulus will be generated internally by the software as per API.
2) Linear elastic spring model based on
In this approach the lateral soil resistance is proportional to depth given by p/y = x z where z is the depth. Values of recommended by Terzaghi (1955) are given below
Table 30 Terzaghi values of n_{h} for sand
Terzaghi values of n_{h} for sand(t/ft^{3}) 

Density 
Loose 
Medium 
Dense 
Dry 
7 
21 
56 
Submerged 
4 
14 
34 
Terzaghi values of n_{h} for sand(kN/m^{3}) 

Density 
Loose 
Medium 
Dense 
Dry 
2420 
7300 
19400 
Submerged 
1400 
4800 
11800 
We may get n_{h} values from the linear segments of py curves recommended by API 2011. These values are given in the table below:
Table 31 API2011 recommendations for n_{h}
φ′ 
kN/m3 
kips/ft3 
25° 
5400 
35 
30° 
11000 
70 
35° 
22000 
140 
40° 
45000 
285 
Table 32 IS2911 recommendations for n_{h} (clause 2.1, 2.31)
Soil Type 
N (Blows / foot) 
Range of n_{h} (kN/m^{3}) 



Dry 
Submerged 
Very loose sand 
0  4 
< 400 
< 200 
Loose sand 
4  10 
400  2500 
200  1400 
Medium sand 
10  35 
2500  7500 
1400  5000 
Dense sand 
> 35 
7500  20000 
5000  12000 
The input required for this model is the nh value for the sand layer in the units adopted.
3) Hybrid model for liquefied sand.
Hybrid model for liquified sand can be used for modelling laterally loaded pile behaviour in sand layers due to liquefaction after an earthquake.
a) Hybrid model based on angle of friction (f) for the layer
b) Hybrid model based on average SPT value for the layer
Note: The hybrid models are available only with SI unit system.
Table 33 Required properties for lateral pile analysis for sand.
Lateral analysis method 
Friction angle (f) 
K subgrade 
Linear variable subgrade modulus 
Fines (%) 
Standard penetration test, average value in layer 
API2011 
✓ 
Optional 



n_{h} Based Horizontal Subgrade Modulus Variation 


✓ 


Hybrid model for liquefied sand (based on f) 
✓ 


✓ 

Hybrid model for liquefied sand (based on SPT) 



✓ 
✓ 
Relative density: Select the relative density of the sand soil from the dropdown menu. The choices are ‘Very Loose’, ‘Loose’, ‘Medium’, ‘Dense’ and ‘Very Dense’ sand. Based on the relative density selection and the ‘Axial analysis method’ selected, the application populates the recommended values for the below parameters. For API2011 and API2000 these are based on the appropriate ‘API recommended’ practices. These values can be replaced by user preferred values.
Note: For ‘Very Loose’ and ‘Loose’ sand, tz/Qz API2011 code doesn’t recommend any values for ‘Shaft friction factor’, ‘Limiting shaft friction (f_{lim}), Limiting end bearing (q_{lim}) and Bearing capacity factor (N_{q}). These need to be prescribed by the user based on soil investigation reports.
Properties for Sandy soil
Table 34 Soil property details for sand
Soil property 
Units 
Min value 
Max value 
Notes 
Elastic modulus of soil 
kN/m^{2} 
11000 
200000 
Default values for the particular 'relative density' will be populated when the ‘axial analysis method’ is set as ‘Elastic method’ 
kips/ft^{2} 
229.68 
4176 

Poisson Ratio 

0.1 
0.5 
Default value: 0.2 
Friction angle (f) 
Deg 
25 
45 
The value is not changed based on selection of ‘relative density of soil’ 
Shaft friction factor (b) 

0.10 
1.0 

Angle of shaft friction (d) 
Deg 
5 
45 
Details in Table 19 Values for interface friction angle δ 
K Earth pressure coefficient 

0.25 
2.0 
Details in Table 20 Guidance values for lateral earth pressure coefficient K 
Limiting shaft friction (f_{lim}) 
kN/m^{2} 
0 
400 

kips/ft^{2} 
0 
8.35 

Limiting end bearing (q_{lim}) 
kN/m^{2} 
0 
15000 

kips/ft^{2} 
0 
313.2 

Bearing capacity factor (N_{q}) 

1.5 
320 

Horizontal subgrade modulus 

> 0 

Ksubgrade may be specified if available. Otherwise, the program calculates the values based on the friction angle provided. Set the value as – to enable auto calculation. 
Linear variable subgrade modulus 
kN/m^{3} 
500 
60000 

kips/ft^{3} 
10 
1250 

Fines 
% 
0 
75 
Percentage of fine particle sand 
Standard penetration test, average value in layer 
Blows/ft 
> 0 

This value is automatically calculated from the SPT table in the SPT tab. The values of 'N values' in the layer are averaged. 
Standard penetration test, value at pile base 
Blows/ft 
> 0 

This value is automatically calculated from the SPT table in the SPT tab. This is the average 'N value'  2D above pile tip and 3D below pile tip. 
Table 35 Values for interface friction angle δ
Type of soil 
Angle of pile soil friction δ (degrees) 
Reference 
Granular soil 
Tan δ range 0.7 to 1.0 
Fleming et al 
Granular soil 
Constant volume friction angle φ_{cv} 
Fleming et al Tomlinson et al 
Very loose sand Loose sand silt Medium silt 
15 
API 2000 
Loose sand Medium sandsilt Dense silt 
20 

Medium sand Dense sand silt 
25 

Dense sand Very dense sand silt 
30 

Dense gravel Very dense sand 
35 
Table 36 Guidance values for lateral earth pressure coefficient K
Pile Type 
K 
Reference 
Driven hollow Tubular steel piles 
0.8 
(API 2000 RP2AWSD 2000) 
Driven cast –insitu piles 
1.2 dry concrete 
Fleming et al

1.0 wet concrete 

Conventional bored piles in sand 
0.7 

Bored cast insitu concrete 
0.7 

Continuous flight augur in sand 
0.9 

Continuous flight augur in silty sand and silt 
0.6 

Precast concrete driven 
1.02.0 (φ = 30^{o} to 40^{o}) 
(IS 2911 Design and construction of pile foundations  Code of Practice (Part 1. Sections  1,2&3) 2010) 
Driven cast –insitu piles 
1.02.0 (φ = 30^{o} to 40^{o}) 

Bored cast insitu concrete 
1.01.5 (φ = 30^{o} to 40^{o}) 
Shaft friction estimate in weak and strong rock strata.
The maximum unit shaft friction is estimated using the equation
Where α is multiplier and is the unconfined compressive strength. Default value of α in the appropriate system of units gets shown in the software however user may also specify value of α.
Base resistance in weak and strong rock strata
The maximum unit base resistance q_{max} is estimated using the expression
A default value of β = 1 is used in the software. Other values between 0.5 and 3 may be adopted based on rock discontinuities and local experience.
Table 37 Required properties for pile capacity estimation for weak rock
Pile capacity estimation 
Unconfined compressive strength 
α factor 
Base resistance factor 
Elastic Method 
✓ 
✓ 
✓ 
Axial analysis method: Select the ‘Axial analysis method’ using the ‘drop down menu’ for axial load analysis.
Table 38 Axial analysis method details for weak rock
Axial analysis method 
Method details 
Elastic method 
Based on elastic properties of rock. 
Table 39 Required properties for Axially loaded pile analysis for weak rock
Axial analysis method 
Unconfined compressive strength 
α factor 
Base resistance factor 
Elastic modulus 
Poisson ratio 
Elastic Method 
✓ 
✓ 
✓ 
✓ 
✓ 
Lateral analysis method: Select the ‘Lateral analysis method’ using the ‘drop down menu’ for lateral load analysis.
Table 40 Lateral analysis method details for weak rock
Lateral analysis method 
Method details 
REESE 
(L. Reese, Analysis of Laterally Loaded Piles in Weak Rock 1997) 
k_{h} Based Horizontal Subgrade Modulus 
Lateral spring of constant stiffness based on k_{h} 
1) Based on the model proposed by Reese(1997)
The py relationship in this model is nonlinear comprising an initial linear segment, a curvilinear segment in the middle followed by a horizontal segment. The rock parameters required for this model are:
q_{u} = unconfined compressive strength
RQD = rock quality designation expressed in percentage
Km = empirical dimensionless parameter
E = elastic modulus of the rock mass in the layer.
2) k_{h} based Subgrade reaction approach.
This is a linear spring model based on k_{h}. The input required is k_{h} value in appropriate unit.
Table 41 Required properties for laterally loaded pile analysis for weak rock
Lateral analysis method 
Unconfined compressive strength 
Rock quality designation 
KRML Constant 
Elastic modulus 
Poisson ratio 
Horizontal subgrade modulus 
REESE 
✓ 
✓ 
✓ 
✓ 
✓ 

k_{h} Based Horizontal Subgrade Modulus 





✓ 
Table 42 Soil property details for weak rock
Property 
Units 
Min value 
Max value 
Notes 
Elastic modulus of soil 
kN/m^{2} 
10^{6} 
2*10^{7} 

kips/ft^{2} 
20880 
417600 

Poisson Ratio 

0.1 
0.5 
Default value: 0.2 
Unconfined compressive strength 
kN/m^{2} 
1000 
20000 

kips/ft^{2} 
20.88 
417.6 

a factor 
(kN/m^{2})^{1/2} 
3 
20 
(Focht Jr. 1973) 
(kips/ft^{2})^{1/2} 
0.433 
2.88 

Base resistance factor 

0.5 
3 
(e. a. Reese 1984) 
Rock quality designation 
% 
0 
100 

KRML constant 

0.00005 
0.0005 

Horizontal subgrade modulus 
kN/m^{3} 
6.5 * 10^{5} 
1.3*10^{7} 

kips/ft^{3} 
1.4 * 10^{4} 
2.7 * 10^{5} 
Shaft friction estimate in hard rock strata.
The maximum unit shaft friction is estimated using the equation
Where α is multiplier and is the unconfined compressive strength. Default value of α in the appropriate system of units gets shown in the software however user may also specify value of α.
Base resistance in hard rock strata
The maximum unit base resistance q_{max} is estimated using the expression
A default value of β = 1 is used in the software. Other values between 0.5 and 3 may be adopted based on rock discontinuities and local experience.
Table 43 Required properties for pile capacity estimation for hard rock
Pile capacity estimation 
Unconfined compressive strength 
α factor 
Base resistance factor 
Elastic Method 
✓ 
✓ 
✓ 
Axial analysis method: Select the ‘Axial analysis method’ using the ‘drop down menu’ for axial load analysis.
Table 44 Axial analysis method details for hard rock
Axial analysis method 
Method details 
Elastic method 
Based on elastic properties of rock. 
Table 45 Required properties for axially loaded pile analysis for hard rock
Axial analysis method 
Unconfined compressive strength 
α factor 
Base resistance factor 
Elastic modulus 
Poisson ratio 
Elastic Method 
✓ 
✓ 
✓ 
✓ 
✓ 
Lateral analysis method: Select the ‘Lateral analysis method’ using the ‘drop down menu’ for lateral load analysis.
Table 46 Lateral analysis method details for hard rock
Lateral analysis method 
Method details 
TURNER (2006) 
(Turner 2006) 
k_{h} Based Horizontal Subgrade Modulus 
Lateral spring of constant stiffness based on k_{h} 
1) Approach proposed by Turner (2006).
The py relationship in this model is nonlinear comprising three linear segments. The slope of the first linear segment is 1000qu up to p=0.4qu and thereafter 50qu up to p=0.5qu after which the line remains horizontal
2) Subgrade reaction based approach.
This is a linear spring model based on k_{h}. The input required is k_{h} value in appropriate unit.
Table 47 Required properties for lateral loaded pile Analysis for hard rock.
Lateral analysis method 
Unconfined compressive strength 
Horizontal subgrade modulus 
TURNER (2006) 
✓ 

k_{h} Based Horizontal Subgrade Modulus 

✓ 
Table 48 Property details for hard rock
Rock Property 
Units 
Min value 
Max value 
Notes 
Elastic modulus of soil 
kN/m^{2} 
1.5*10^{7} 
10^{8} 

kips/ft^{2} 
313200 
2088000 

Poisson Ratio 

0.1 
0.5 
Default value: 0.25 
Unconfined compressive strength 
kN/m^{2} 
10000 
100000 

kips/ft^{2} 
208.8 
2088 


a factor 

3 
20 

Base resistance factor 

0.2 
3 

Horizontal subgrade modulus 
kN/m^{3} 
9.8 * 10^{6} 
6.5 * 10^{7} 

kips/ft^{3} 
2.1 * 10^{5} 
1.35 * 10^{6} 
SPT tab is used to define the standard penetration test results.
The data in this tab is required for pile capacity estimation and axial load analysis for sand soil layer when ‘Meyerhoff SPT method (IS2911)’ is selected as the 'Method for maximum side friction' or as the 'Method for maximum base resistance'.
This data is also required for lateral load analysis for sand soil layer when ‘Hybrid model for liquified sand (based on SPT)’ is selected.
For sand layers, the 'standard penetration test avg value in layer' is calculated by averaging the values in the layer and displayed in the soil layer tab in the ' Soil Layer Properties ' pane. This value is used when the 'method for maximum side friction' is set as one of 'Meyerhoff SPT method (IS2911)'. This data is also used for lateral load analysis for sand soil layer when ‘Hybrid model for liquified sand (based on SPT)’ is selected
When the pile terminates in the sand layer, the 'standard penetration test value at pile base' is calculated by averaging the values from pile tip – 2D and pile tip + 3D and displayed in the soil layer tab in the 'Soil Layer Properties' pane (D is the effective Diameter of the pile). This value is used when one of 'Meyerhoff SPT method (IS2911)' is selected as the ' method for maximum base resistance '.
The ‘SPT Table’ contains the corrected data from the SPT test performed.
Use the (+) and () buttons at the top of the table to add / delete rows to the SPT table.
[Organize] button can be used to sort the values in ascending order of depth and to clean up empty entries in the table.
Up to 100 SPT points can be specified in the table.
Table:
Doubleclick on the table cells to edit the content of the cells.
The table consists of three columns: No., Depth, N Value.
‘No.’ column cannot be edited and displays the entry index.
Depth Column – Contains the depth at which the test is done.
N Value Column – Contains the corrected 'N' value of the test and specified as number of blows per foot
Right click on the table to bringup the context menu to insert / delete rows in the table, cut, copy, delete and paste contents into the table. It is also possible to copy the table from excel and paste the contents into this table. Ensure adequate number of empty rows are added to the table prior to pasting contents from an excel table.
The SPT graph plots the data in the ‘SPT table’.
The ‘Load Cases’ tab is used to enter details of the loading on the pile.
It is important to first specify the ‘Number of loadcases’ in the ‘Project Properties Pane’. This will setup the appropriate number of tabs under the ‘Load Cases Tab’ for specifying the details of each load case.
Each loadcase should be entered in a separate tab (on the righthand side). Each load case tab consists of details of the load applied on the pile along with a loading diagram that graphically represents the same.
Enter the description of the load case for your reference. This is an editable text field.
Specify the axial load applied on the pile at the pile head. Compressive loads (+ve) values act downward while tensile loads (ve) values act upwards.
Specify the lateral load applied on the pile head.
For Circular and Square crosssection piles, the load acts along the X direction.
For Rectangular and HSection piles, depending on the ‘Direction of loading’ selected in the ‘Pile Dimensions’ tab, load may act along the X or Y direction.
Specify the moment load applied at the pile head.
Note: that counterclockwise moment is +ve. If clockwise moment is to be applied, then prefix a –ve sign to the value.
For Circular and Square crosssection piles, the moment acts around the Y direction.
For Rectangular and HSection piles, depending on the ‘Direction of loading’ selected in the ‘Pile Dimensions’ tab, moments may act around the X or Y direction.
The figure above shows an axial load of 1000kN, lateral load of 100kN and a lateral moment of 20kNm applied at the pile head.
Include ‘selfweight’ in analysis
Select this checkbox if the weight of the pile is to be included in the analysis. The weight of the pile is used in axial analysis only. It is not taken into consideration for lateral analysis
The “selfweight” of the pile consists of pile weight and plug weight and is taken from the ‘Self weight inputs’ pane in the ‘Pile Properties’ tab.
Loading type can either be static loading or cyclic loading. Use the radio button to select the option. Cyclic loading is used to simulate long term effects of wave action on a long pile.
Along with the load applied at the pile head, concentrated loads (axial load, lateral load, lateral moment) can be applied along the length of the pile. In addition, a distributed lateral load can also be applied. These can be useful for modelling wave action, water currents, piers, loads applied on single buoy mooring piles.
The distributed lateral load can be used to model distributed loads along the length of the pile. The loads can be triangular, uniform, or trapezoidal. This is especially useful for modelling the effects of wave actions and water currents on the pile.
For Circular and Square crosssection piles, the load acts along the X direction.
For Rectangular and HSection piles, depending on the ‘Direction of loading’ selected in the ‘Pile Dimensions’ tab, load may act along the X or Y directions
Specify the starting depth, ending depth along with the load at the starting depth and load at the ending depth. If any of the values are left blank, then it is assumed that no distributed load is being applied.
The figure above shows a trapezoidal load of 20kNm to 30kNm applied from a depth of 2m to 5m on the pile.
This table is used to specify the additional concentrated loads and moments applied on the pile along its length.
The example above shows a pile with 30kN tensile and 30kNm lateral load applied at 6m depth.
Use the (+) and () buttons at the top of the table to add / delete rows to the Concentrated Load Table'.
[Organize] button can be used to sort the values in ascending order of ‘depth’ and to clean up empty entries in the table.
Table Columns:
Depth: Specify the depth where the load is applied.
Note: A total of 20 unique depths with axial loads can be specified for axial analysis across load cases.
Axial load: Specify the axial load applied at the point. Compressive loads (+ve) values act downward while tensile loads (ve) values act upwards.
Note: Only the axial load applied at the pile head is included in the calculation of beamcolumn effect for lateral load analysis.
Lateral load: Specify the lateral load applied at the point.
For Circular and Square crosssection piles, the load acts along the X direction.
For Rectangular and HSection piles, depending on the ‘Direction of loading’ selected in the ‘Pile Dimensions’ tab, load may act along the X or Y direction.
Moment: Specify the moment applied at the point.
Note: that counterclockwise moment is +ve. If clockwise moment is to be applied, then prefix a –ve sign to the value.
For Circular and Square crosssection piles, the moment acts around the Y direction.
For Rectangular and HSection piles, depending on the ‘Direction of loading’ selected in the ‘Pile Dimensions’ tab, moments may act around the X or Y direction.
Right click on the table to bringup the context menu to insert / delete rows in the middle of the table, cut, copy, delete and paste contents into the table. It is also possible to copy the table from excel and paste the contents into this table. Ensure adequate number of empty rows are added to the table prior to pasting contents from an excel table.
The loading diagram represents the axial load, lateral load, and a distributed lateral load (trapezoidal) applied on the pile for a load case.
Reese, et al. “Analysis of a Pile Group under Lateral Loading, Laterally Loaded Deep Foundations: Analysis and Performance.” ASTM, STP 835, 1984: 5671.
Reese, L.C., and W.R. Cox. “Field Testing and Analysis of Laterally Loaded Piles in Stiff Clay.” 5th Annual Offshore Technology Conference. Houston, Texas, April 1975.
“API 2000 RP2AWSD.” American Petroleum Institute WSD, 2000.
Fleming, K, A Weltman, M Randolph, and K Elson. Piling Engineering. Third. London: Taylor & Francis, 2009.
Terzaghi, K., R. B. Peck, and G. Mesri. Soil Mechanics in Engineering Practice. Third Edition. New York: John Wiley, n.d.
Tomlinson, M., and J. Woodward. Pile Design and Construction Practice. Fifth Edition. London: Taylor and Francis, n.d.
Reese, L. C., W. R. Cox, and F. D. Koop. “Analysis of laterally loaded piles in sand.” Proceedings of the offshore technology conference (OTC 2080). Houston, 1974.
Poulos, H. G., and E. H. Davis. Pile Foundation Analysis and Design. 1980, n.d.
Turner, J. RockSocketed Shafts for Highway Structure Foundations. In:Program, N.C.H.R (Ed) A Synthesis of Highway Practice, Transportation Research Board of the National Academies, 2006.
“API 2011 Geotechnical and Foundation Design Considerations.” ANSI/API RP2GEO, April 2011, Addendum 1, 2014.
Focht Jr., John A. Koch, Kenneth. J. “Rational Analysis of the Lateral Performance of Offshore Pile Groups.” Offshore Technology Conference. 1973. Paper No 1896.
Reese, L.C. “Analysis of Laterally Loaded Piles in Weak Rock.” Journal of Geotechnical and Geoenvironmental Engineering 123 (1997): 10101017.
Terzaghi, K. “Estimation of coefficient of subgrade reaction.” Geotechnique Vol.5, no. No. 4 (1955): 4150.
Semple, R. M., and W. J. Rigden. “Shaft capacity of driven piles in clay.” Proc. ASCE National Convention. San Francisco, 1984.
Kolk, H. J., and E. van der Velde. “A reliable method to determine friction capacity of piles driven into clay.” Proc. Offshore technology conf. OTC 7993. Houston, 1996.
Randolph, M. F., and C. P. Wroth. “Analysis of deformation of vertically loaded piles.” ASCE, Geotech Eng Div. 104(GT12) (1978): 14651488.
“IS 2911 Design and construction of pile foundations  Code of Practice (Part 1. Sections  1,2&3).” 2010.
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