ENGINEERING – GEOTECHNICAL ENGINEERING CALCULATOR
Retaining Wall Stability
A precise tool.
What is the Retaining Wall Stability & How does it work?
Retaining walls must resist the forces generated by the retained soil mass. The primary actions are the vertical and horizontal pressures that create overturning moments about the toe of the wall. Engineers evaluate these actions using the concepts of active earth pressure, surcharge loads, and the wallβs own weight.
Two critical stability checks are performed: an overturning check, which compares the resisting moment produced by the wallβs weight and any passive resistance, to the overturning moment caused by soil pressure; and a sliding check, which compares the frictional and cohesive resistance at the base to the horizontal driving forces.
If the calculated factors of safety exceed the required values (typicallyβ―β₯β―1.5 for overturning andβ―β₯β―1.5 for sliding), the wall is considered stable. The calculations are based on simplified assumptions that are suitable for preliminary design and quick verification.
M_{o}=sum P_{i},h_{i}=frac{gamma,H^{2},B}{2}+frac{q,H,B}{2}
M_{o} = overturning moment (kNΒ·m)
gamma = unit weight of soil (kN/mΒ³)
H = wall height (m)
B = base width (m)
q = uniform surcharge (kN/mΒ²)
gamma = unit weight of soil (kN/mΒ³)
H = wall height (m)
B = base width (m)
q = uniform surcharge (kN/mΒ²)
Parameters
Result
β
Frequently Asked Questions
What are the primary actions that create overturning moments in a retaining wall?
The primary actions are vertical and horizontal pressures from the retained soil mass.
How do engineers evaluate the stability of retaining walls?
Engineers use concepts like active earth pressure, surcharge loads, and the wall’s own weight to assess stability.
What are the two critical stability checks for retaining walls?
The two critical checks are an overturning check and a sliding check.
How does the resisting moment in an overturning check compare to the overturning moment?
The resisting moment, produced by the wall’s weight and passive resistance, is compared to the overturning moment generated by soil pressures.
What factors are considered in calculating active earth pressure?
Factors include the angle of internal friction of the soil, cohesion, and the height of the retained soil mass.
Results are for informational purposes only and do not constitute professional advice.