Geotechnical Calculation Library
(developing continues...)
Geotechnical calculation online
library is created to provide geotechnical engineers easily
accessible and reliable solutions to some of the most common geotechnical
problems including ground settlements from onedimensional soil
consolidation (stresses calculated using the Boussinesq's
equation), finite element solutions of the Terzaghi's
consolidation equation, static Coulomb's and dynamic MononobeOkabe soil
pressure coefficients, simple design calculation for mechanically stabilized
earth structures, lock block retaining walls, and others. This library is developed under the supervision of
Dr. Guoxi Wu, Ph.D., P.Eng. of BC, Canada
please go to HOME and accept limitation of liability before starting calculation...
The following applications
are available as of August 20, 2012:
All calculations, including the finite
element consolidation analysis, are carried out on the web server. A
computer is not required to run the program; instead only an Internet browser is
needed to setup input and display results.
WickDrain provides a simplified calculation of consolidation time for
vertical drains.
The calculation employs Barron's equation which only
requires three input parameters, i.e., diameter of vertical
drains,
diameter of vertical drain influence zone, and coefficient
of consolidation for drainage in horizontal direction.
Consolidation Settlement
provides calculations of consolidation induced settlements of clayey soils in a
multilayer column. Each layer can have
its own unique soil properties including total unit weight, initial void ratio,
compression index Cc and recompression index Cr. The preconsolidation pressure (sp’) can be assigned a constant value or as a ratio
of the initial effective vertical stress for each layer. Settlement at any location, expressed by X
and Y coordinate, under multizones of loading can be calculated. The incremental vertical stresses under
the point of interest are computed using the Boussinesq's equation and the
method of superposition for the multizones of loads. Once the ground water level is specified
by the user, the program automatically computes the initial effective vertical
stress for each soil layer, including sublayers .
A soil layer is divided automatically by the program into many sublayers
as desired by the user in order to increase the accuracy of calculation. Finally the program computes the primary
consolidation settlement for underconsolidated soil (OCR<1), or normally
consolidated soil(OCR=1), or overconsolidated soil (OCR>1). Secondary compression settlement can also
be computed.
Consolidation analysis
provides finite element solutions of the Terzaghi's consolidation equation in
multilayer column. This calculation
is a continuation of Consolidation Settlement , which compute stresses in soils using the
Boussinesq's equation for multizones of loading and calculate consolidation
induced settlement of clayey soils. Each
soil layer can have its own unique coefficient of consolidation (Cv), and the drainage conditions at the
bottom of each layer are specified while the top (zero depth) of the column is assumed to be free drained. In the analysis the pore water
pressure at t=0 is assumed to be the same as the incremental stresses carried
over from Consolidation Settlement. The Terzaghi’s 1D
consolidation equation is solved using the finite element method. The results of analysis include
settlements of each soil layer and sublayer for up to 4 specific points of time,
as well as a complete curve of settlement versus time for up to 4 specific
locations (sublayer) in the soil column.
Soil Pressure Coefficient (Ka, Kp)
provides calculation of later earth pressure coefficients for cohesionless soils
(sandy soils) , including Coulomb's active and passive coefficients under static
conditions, and MononobeOkabe active and passive soil pressure coefficients
under seismic loading. Base input parameters include soil friction angle (phi),
back slope angle (i), wallsoil interface friction angle, wall inclination angle
(beta), and horizontal and vertical seismic coefficient (kh and kv).
Total amount of lateral force on a retaining wall is also computed with a
specified wall height and the unit weight of the backfill.
Anchorage Wall provides design calculation
of an anchored retaining wall including external global stability (factors of
safety on sliding, overturning and bearing), and internal anchor stability
(factors of safety on anchor yield and anchor pullout). Base input parameters
include anchor length, anchor vertical and horizontal spacing, dipdown angle,
anchor yield force, anchorgroutsoil bonding coefficient, and backfill soil
unit weight and lateral pressure coefficients (Ka or Kae), which may be obtained
in advance using (Ka, Kp). In addition to a triangle distribution of
lateral soil pressure, the calculation module also allows for a trapezoid
distribution especially for simulation of seismic soil pressure where soil
pressure is nonzero at the wall top. The web page includes an
easytounderstand force diagram for the anchored wall, and all equations used
in the calculation can be downloaded on the web page through the tab “Download
Calculation Note”.
MSE Wall provides design calculation of a
mechanically stabilized earth retaining wall including external global stability
(factors of safety on sliding, overturning and bearing), and internal
reinforcement stability (factors of safety on rupture and pullout). Base input
parameters include reinforcement length (assumed to be horizontal), vertical
arrangement, reinforcement tensile/rupture load capacity, soil/reinforcement
frictional coefficient, and backfill soil unit weight and lateral pressure
coefficients (Ka or Kae), which may be obtained in advance using
(Ka, Kp).
In addition to a triangle distribution of lateral soil pressure, the calculation
module also allows for a trapezoid distribution especially for simulation of
seismic soil pressure where soil pressure is nonzero at the wall top. The web
page includes an easytounderstand force diagram for the MSE wall, and all
equations used in the calculation can be downloaded on the web page through the
tab “Download Calculation Note”.
Segmental Block Wall provides design
calculation of a segmental block retaining wall, including factors of safety on
sliding and overturning for each block on the wall. Maximum pressure at the
base of each block is calculated using two methods, i.e., the Meyerhof method
and the method assuming a triangular distribution of base reaction. Base input
parameters include size/weight of blocks and its arrangement, interblock
friction angle and base friction angle, wall/soil friction, wall inclination
angle, and backfill soil unit weight and lateral pressure coefficients (Ka or
Kae), which may be obtained in advance using
(Ka, Kp). In addition to a
triangle distribution of lateral soil pressure, the calculation module also
allows for a trapezoid distribution especially for simulation of seismic soil
pressure where soil pressure is nonzero at the wall top. The web page includes
an easytounderstand force diagram for the segmental block wall, and all
equations used in the calculation can be downloaded on the web page through the
tab “Download Calculation Note”.
The following applications are yet to come:
