Width of Footing given Round Footing and Bearing Capacity Calculator

Width of Footing Formula:

\[ B_{round} = \frac{q_f - ((1.3 \times C \times N_c) + (\sigma' \times N_q))}{0.5 \times N_\gamma \times \gamma \times 0.6} \]

Ultimate Bearing Capacity (qf):

Cohesion (C):

Bearing Capacity Factor (Nc):

Effective Surcharge (σ'):

Bearing Capacity Factor (Nq):

Bearing Capacity Factor (Nγ):

Unit Weight of Soil (γ):

N/m³

Width of Footing (B_round): m

Definition: This calculator determines the required width of a round footing based on soil bearing capacity parameters.

Purpose: It helps civil engineers design appropriate foundation dimensions to ensure structural stability.

The calculator uses the formula:

\[ B_{round} = \frac{q_f - ((1.3 \times C \times N_c) + (\sigma' \times N_q))}{0.5 \times N_\gamma \times \gamma \times 0.6} \]

Where:

Details: Proper footing width ensures the foundation can support structural loads without excessive settlement or shear failure.

Tips: Enter all required parameters. Bearing capacity factors typically have ±5% variability. All values must be positive.

Q1: What is ultimate bearing capacity?
A: The maximum pressure the soil can withstand before shear failure occurs.

Q2: Why ±5% for bearing capacity factors?
A: These factors are empirically derived and typically have about 5% variability.

Q3: How do I determine soil cohesion?
A: Cohesion is determined through laboratory tests like unconfined compression tests.

Q4: What's typical unit weight for soil?
A: Typically ranges from 16-22 kN/m³ (16,000-22,000 N/m³) for most soils.

Q5: When would I use this calculation?
A: When designing circular footings for structures like towers, silos, or columns.