More detailed information on the infinite slope equation.
Applet
A Java applet designed to let people fool around with the infinite slope model without spending an hour trying to figure out how to run it through their calculator. The equation measures slope strength versus stress, and values below 1.0 as a result generally indicate that the slope will fail (hence the red text). Try fiddling with the water table level, and see how much lower the slope angle has to be set to support a full water table versus a slope with no water table.
- If you have local support for Java, run the following classes.
- slope.tar.gz with the source code as a bonus.
- To run as an applet, use the following code in an HTML document. Not sure what the newer <object> tag to run the Java modern browsers would want.
<applet code="Slope.class" width="450" height="350">
<param name="slope_angle" value="30">
<param name="phi" value="30">
<param name="cohesion" value="1000">
<param name="density_soil" value="2000">
<param name="water_table" value="0.5">
<param name="failure_depth" value="0">
<param name="gravity" value="9.81">
<param name="density_water" value="1000.0">
</applet>
Notes
- Units are meters, kilograms, and seconds.
- What the text fields mean.
- Angle of the slope to calculate the factor of safety for (degrees).
- Percentage (0 to 1) of failure plane filled by the water table. Zero would indicate no water present, while a value of 1 places the water table at ground level.
- The depth of the failure plane (meters). Translation: how thick of a slab will be sliding down the hillside?
- cohesion, a measure of the slope’s material strength (Pascals).
- density (kg/m^3) of the material in question.
- phi, commonly known as the “internal angle of friction,” measured in degrees. (Response of a material to shear stress, determined in laboratories.)
- The applet draws on the following equation in its calculations.
