Area between Bearing Plate and Concrete Foundation using Compressive Stress Calculator

Area Calculation Formula:

\[ A = \frac{\Sigma W}{f_{concrete} - \left(\frac{M_s}{Z}\right)} \]

Total Weight of Vessel:

Max Compressive Stress of Concrete:

Maximum Seismic Moment:

N·m

Section Modulus of Area A:

mm²

Area between Bearing Plate & Concrete Foundation:

1. What is Area between Bearing Plate and Concrete Foundation?

Definition: This calculator determines the required contact area between a bearing plate and concrete foundation based on compressive stress calculations.

Purpose: It ensures the foundation can safely support the vessel's weight and seismic moments without exceeding concrete's compressive strength.

2. How Does the Calculator Work?

The calculator uses the formula:

\[ A = \frac{\Sigma W}{f_{concrete} - \left(\frac{M_s}{Z}\right)} \]

Where:

\( A \) — Required area (mm²)
\( \Sigma W \) — Total weight of vessel (N)
\( f_{concrete} \) — Maximum compressive stress of concrete (Pa)
\( M_s \) — Maximum seismic moment (N·m)
\( Z \) — Section modulus of area A (mm²)

Explanation: The formula calculates the minimum area needed to distribute the load so that the concrete's compressive strength isn't exceeded, accounting for both static weight and seismic moments.

3. Importance of This Calculation

Details: Proper area calculation prevents concrete crushing, ensures structural stability, and meets safety standards for vessel foundations.

4. Using the Calculator

Tips: Enter all required values with appropriate units. Note that all inputs have a ±5% tolerance. Ensure values are positive and the denominator doesn't become zero.

5. Frequently Asked Questions (FAQ)

Q1: Why include seismic moment in the calculation?
A: Seismic moments create additional stresses during earthquakes that must be accounted for in foundation design.

Q2: What's a typical compressive stress for concrete?
A: Varies by concrete mix, but commonly 20-40 MPa (20,000,000-40,000,000 Pa) for structural concrete.

Q3: How do I determine the section modulus?
A: It depends on the foundation's cross-sectional shape. For common shapes, use standard formulas or structural tables.

Q4: What if my calculation results in negative area?
A: This indicates the combination of weight and seismic moment exceeds the concrete's capacity. Redesign with stronger concrete or larger foundation.

Q5: Should I include a safety factor?
A: The ±5% tolerance provides some safety margin, but additional factors may be required by local codes.