Creep Coefficient in European Code Calculator

Creep Coefficient Formula:

\[ \Phi = \frac{\delta_t}{\delta_i} \]

Creep Coefficient (Φ):

1. What is Creep Coefficient in European Code?

Definition: The creep coefficient (Φ) is the ratio of creep strain to elastic strain in concrete under sustained load.

Purpose: It quantifies the long-term deformation of concrete structures due to sustained loads, which is crucial for structural design.

2. How Does the Calculator Work?

The calculator uses the formula:

\[ \Phi = \frac{\delta_t}{\delta_i} \]

Where:

\( \Phi \) — Creep coefficient (dimensionless)
\( \delta_t \) — Total strain including creep effects (%)
\( \delta_i \) — Instantaneous elastic strain (%)

Explanation: The total strain is divided by the instantaneous strain to determine how much additional deformation occurs over time.

3. Importance of Creep Coefficient

Details: Creep affects long-term deflections, prestress losses, and stress redistribution in concrete structures. Proper calculation ensures structural safety and serviceability.

4. Using the Calculator

Tips: Enter both strain values as percentages. The total strain should be greater than the instantaneous strain for meaningful results.

5. Frequently Asked Questions (FAQ)

Q1: What is a typical range for creep coefficient?
A: In Eurocode, creep coefficients typically range from 1.0 to 4.0 depending on concrete age, humidity, and member size.

Q2: How does Eurocode 2 calculate creep coefficient?
A: Eurocode 2 provides detailed methods considering concrete strength, relative humidity, member dimensions, and load duration.

Q3: Why is creep important in concrete design?
A: Creep causes additional long-term deflections and stress redistribution that must be accounted for in design.

Q4: How does creep coefficient affect prestressed concrete?
A: Creep leads to prestress losses over time, reducing the effective prestress force in tendons.

Q5: What factors influence the creep coefficient?
A: Key factors include concrete composition, age at loading, ambient humidity, member size, and duration of loading.