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Net Effective Weight of Dam Calculator

Net Effective Weight Formula:

\[ W_{net} = W - \left(\frac{W}{g} \times a_v\right) \]

kN
m/s²
m/s²

1. What is Net Effective Weight of Dam?

Definition: The net effective weight of dam is the weight of the dam body and its foundation is the major resisting force.

Purpose: It helps engineers determine the actual resisting force of a dam considering vertical acceleration effects.

2. How Does the Calculator Work?

The calculator uses the formula:

\[ W_{net} = W - \left(\frac{W}{g} \times a_v\right) \]

Where:

  • \( W_{net} \) — Net effective weight of dam (kN)
  • \( W \) — Total weight of dam (kN)
  • \( g \) — Gravity adapted for vertical acceleration (m/s²)
  • \( a_v \) — Fraction gravity adapted for vertical acceleration (m/s²)

Explanation: The total weight is adjusted by subtracting the component affected by vertical acceleration.

3. Importance of Net Effective Weight Calculation

Details: Proper calculation ensures dam stability under seismic conditions and other vertical acceleration scenarios.

4. Using the Calculator

Tips: Enter the total weight in kN, gravity (default 9.81 m/s²), and fraction gravity (default 0.98 m/s²). All values must be > 0.

5. Frequently Asked Questions (FAQ)

Q1: Why do we need to calculate net effective weight?
A: It accounts for the reduction in resisting force due to vertical acceleration effects.

Q2: What's the typical value for gravity?
A: Standard gravity is 9.81 m/s², but local variations may exist.

Q3: How is fraction gravity determined?
A: It's typically a percentage (e.g., 10% = 0.98 m/s²) based on seismic analysis.

Q4: What units should be used?
A: The calculator uses kN for weight and m/s² for acceleration values.

Q5: Does this include safety factors?
A: No, safety factors should be applied separately based on design codes.

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