Volume of Empty Capillary Pores Calculator

Empty Capillary Pores Formula:

\[ V_{ec} = V_{cp} - V_{wcp} \]

Volume of Empty Capillary Pores (m³):

1. What is Volume of Empty Capillary Pores?

Definition: This calculator determines the volume of capillary pores that are not occupied by any floccules in cement paste.

Purpose: It helps in analyzing the pore structure of hydrated cement paste, which affects concrete's durability and strength.

2. How Does the Calculator Work?

The calculator uses the formula:

\[ V_{ec} = V_{cp} - V_{wcp} \]

Where:

\( V_{ec} \) — Volume of empty capillary pores (m³)
\( V_{cp} \) — Volume of capillary pores (m³)
\( V_{wcp} \) — Volume of water filled capillary pores (m³)

Explanation: The empty capillary pore volume is simply the total capillary pore volume minus the water-filled portion.

3. Importance of Empty Capillary Pores Calculation

Details: Understanding empty capillary pores helps in assessing concrete's permeability, freeze-thaw resistance, and potential for chemical attack.

4. Using the Calculator

Tips: Enter the total capillary pore volume and water-filled capillary pore volume in cubic meters. Both values must be ≥ 0, and total volume must be ≥ water-filled volume.

5. Frequently Asked Questions (FAQ)

Q1: What are capillary pores in concrete?
A: Capillary pores are the void spaces in cement paste that remain after hydration, typically ranging from 10-50 nm in diameter.

Q2: Why measure empty capillary pores?
A: Empty pores affect concrete's permeability and durability more than water-filled pores.

Q3: How are these volumes typically measured?
A: Through techniques like mercury intrusion porosimetry or water absorption tests.

Q4: What's a typical range for empty capillary pores?
A: In well-hydrated cement paste, empty capillary pores might constitute 10-30% of total capillary pores.

Q5: How does this relate to concrete strength?
A: Generally, more empty capillary pores mean lower strength and higher permeability.