Bearing Capacity Factor Dependent on Weight given Effective Surcharge Calculator

Bearing Capacity Factor Formula:

\[ N_γ = \frac{q_{nf} - (C_s \times N_c + σ_s \times (N_q - 1))}{0.5 \times γ \times B} \]

Net Ultimate Bearing Capacity:

Cohesion of Soil:

Bearing Capacity Factor (Cohesion):

Effective Surcharge:

kPa

Bearing Capacity Factor (Surcharge):

Unit Weight of Soil:

N/m³

Width of Footing:

Bearing Capacity Factor (Unit Weight):

1. What is Bearing Capacity Factor Dependent on Weight?

Definition: This calculator determines the bearing capacity factor (Nγ) that depends on the unit weight of soil, considering effective surcharge and other soil parameters.

Purpose: It helps geotechnical engineers calculate the bearing capacity of shallow foundations.

2. How Does the Calculator Work?

The calculator uses the formula:

\[ N_γ = \frac{q_{nf} - (C_s \times N_c + σ_s \times (N_q - 1))}{0.5 \times γ \times B} \]

Where:

\( N_γ \) — Bearing capacity factor dependent on unit weight
\( q_{nf} \) — Net ultimate bearing capacity (Pa)
\( C_s \) — Cohesion of soil (Pa)
\( N_c \) — Bearing capacity factor dependent on cohesion (±5%)
\( σ_s \) — Effective surcharge (kPa)
\( N_q \) — Bearing capacity factor dependent on surcharge (±5%)
\( γ \) — Unit weight of soil (N/m³)
\( B \) — Width of footing (m)

3. Importance of Bearing Capacity Calculation

Details: Accurate calculation ensures foundation stability, prevents settlement issues, and optimizes design for safety and cost-effectiveness.

4. Using the Calculator

Tips: Enter all required parameters with correct units. The bearing capacity factors (Nc and Nq) include a ±5% margin of error.

5. Frequently Asked Questions (FAQ)

Q1: What is the typical range for Nγ?
A: Nγ typically ranges from 0 to 50 depending on soil type and conditions.

Q2: Why is there a ±5% margin for Nc and Nq?
A: These factors have inherent variability based on soil conditions and empirical relationships.

Q3: How do I determine effective surcharge?
A: Effective surcharge is the vertical stress at foundation level from overlying soil layers.

Q4: What if my soil has no cohesion?
A: For cohesionless soils, set cohesion (Cs) to zero in the calculation.

Q5: How does footing width affect the result?
A: Wider footings generally have higher bearing capacity due to deeper influence zones.