Net Ultimate Bearing Capacity given Ultimate Bearing Capacity Calculator

Net Ultimate Bearing Capacity Formula:

\[ q_{net} = q_f - \sigma_s \]

Net Ultimate Bearing Capacity (kPa):

1. What is Net Ultimate Bearing Capacity?

Definition: Net Ultimate Bearing Capacity of Soil is the minimum net pressure intensity causing shear failure.

Purpose: It helps geotechnical engineers determine the safe bearing capacity of soil for foundation design.

2. How Does the Calculator Work?

The calculator uses the formula:

\[ q_{net} = q_f - \sigma_s \]

Where:

\( q_{net} \) — Net Ultimate Bearing Capacity (kPa)
\( q_f \) — Ultimate Bearing Capacity (kPa)
\( \sigma_s \) — Effective Surcharge (kPa)

Explanation: The net capacity is calculated by subtracting the effective surcharge from the ultimate bearing capacity.

3. Importance of Net Ultimate Bearing Capacity

Details: Proper calculation ensures foundation stability and prevents excessive settlement or shear failure of the soil.

4. Using the Calculator

Tips: Enter the ultimate bearing capacity and effective surcharge in kPa. All values must be ≥ 0. Results include ±5% margin.

5. Frequently Asked Questions (FAQ)

Q1: What is effective surcharge?
A: Effective surcharge refers to the vertical pressure or load acting over the ground surface in addition to basic earth pressure.

Q2: Why is there a ±5% margin?
A: The margin accounts for variations in soil properties and measurement uncertainties.

Q3: How do I determine ultimate bearing capacity?
A: Ultimate bearing capacity can be determined through field tests or calculated using soil mechanics formulas.

Q4: What units should I use?
A: The calculator uses kilopascals (kPa) for all inputs and outputs.

Q5: Can effective surcharge be zero?
A: Yes, if there's no additional load beyond the basic earth pressure.