1. What is Ultimate Tensile Strength for Concrete?

The ultimate tensile strength (UTS) of concrete is the maximum stress that concrete can withstand when subjected to tension. While concrete is much stronger in compression than in tension, knowing its tensile strength is important for structural analysis.

2. How Does the Calculator Work?

The calculator uses the empirical equation:

Where:

• \( UTS \) — Ultimate tensile strength (MPa)
• \( f'_c \) — Compressive strength of concrete (MPa)

Explanation: This equation provides an approximate relationship between the compressive strength and tensile strength of concrete.

3. Importance of UTS Calculation

Details: While concrete is rarely designed to resist direct tension, knowing its tensile strength is important for understanding cracking behavior, shear resistance, and bond strength with reinforcement.

4. Using the Calculator

Tips: Enter the compressive strength of concrete in MPa. The value must be positive (typical range 20-100 MPa for normal strength concrete).

5. Frequently Asked Questions (FAQ)

Q1: How accurate is this formula?
A: This is an approximate formula. Actual tensile strength can vary by ±20% depending on aggregate type, curing conditions, and other factors.

Q2: Why is concrete weak in tension?
A: Concrete contains microcracks that propagate easily under tensile stress, unlike compressive stress which tends to close these cracks.

Q3: What are typical UTS values for concrete?
A: For normal concrete (f'c = 20-40 MPa), UTS is typically 2-3 MPa. High-strength concrete may have UTS up to 5 MPa.

Q4: Are there other ways to measure concrete tensile strength?
A: Yes, direct methods include the splitting tensile test (Brazilian test) and flexural strength test.

Q5: How does reinforcement affect tensile strength?
A: Reinforcement carries most tensile loads in concrete structures. The concrete's tensile strength primarily affects cracking behavior.