Arrango theory

The program follows the Coulomb theory to compute the values of K_a and K_p while taking into account the dynamic values (α^*, β^*).

For active earth pressure:

For passive earth pressure:

where:	β	-	slope inclination
	α	-	back face inclination of the structure
	ψ	-	seismic forces inclination

The coefficients of earth pressures K_ae and K_pe are found by multiplying the coefficients F_ae and F_pe by the values of K_a and K_p, respectively.

where:	α	-	back face inclination of the structure
	ψ	-	seismic forces inclination

If the value of the angle β^* becomes larger than φ the program assumes the value (β^* = φ). The values of computed and modified angle β^* can be visualized in the output – in latter case the word MODIFIED is also displayed. It is the user's responsibility to check in such case whether the obtained results are realistic.

Example of the program output

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Literature:

Design of sheet pile walls, Pile Buck Inc., Vero Beach, Florida, www.pilebuck.com