Weight of Soil Prism in Stability Analysis Calculator

Weight of Prism Formula:

\[ W = \gamma \times z \times b \times \cos(I) \]

Unit Weight of Soil:

kN/m³

Depth of Prism:

Inclined Length:

Angle of Inclination:

Weight of Prism: kN

1. What is Weight of Soil Prism in Stability Analysis?

Definition: This calculator computes the weight of a soil prism used in slope stability analysis, considering the unit weight of soil, prism dimensions, and slope angle.

Purpose: It helps geotechnical engineers determine the driving force in slope stability calculations.

2. How Does the Calculator Work?

The calculator uses the formula:

\[ W = \gamma \times z \times b \times \cos(I) \]

Where:

\( W \) — Weight of prism (kN)
\( \gamma \) — Unit weight of soil (kN/m³)
\( z \) — Depth of prism (m)
\( b \) — Inclined length of prism (m)
\( I \) — Angle of inclination (degrees)

Explanation: The weight is calculated by multiplying the soil unit weight by the prism volume, adjusted for the slope angle.

3. Importance of Prism Weight Calculation

Details: Accurate weight calculation is crucial for determining the stability of slopes and embankments in geotechnical engineering.

4. Using the Calculator

Tips: Enter the unit weight of soil, prism depth, inclined length, and slope angle. All values must be > 0 (angle 0-90°). Results include ±5% tolerance.

5. Frequently Asked Questions (FAQ)

Q1: Why is the angle important in this calculation?
A: The cosine of the angle accounts for the component of weight acting perpendicular to the slope.

Q2: What's a typical unit weight for soil?
A: Common values range from 16-22 kN/m³ for most soils, depending on moisture content and composition.

Q3: How do I determine the inclined length?
A: Measure along the slope from the top to the base of the prism being analyzed.

Q4: Why is there a ±5% tolerance?
A: This accounts for natural variability in soil properties and measurement uncertainties.

Q5: Can this be used for other materials besides soil?
A: Yes, if you know the unit weight of the material, it can be used for rock or other granular materials.