Guide
Cement, Mortar and Concrete Testing with Impulse Excitation
Mechanical testing methods for cementitious materials using impulse excitation to measure strength, durability, and detect cracks non-destructively.
Author: dr.ir. Alex Van den Bossche
Overview
Mechanical testing of cementitious materials is essential for both material development and quality assurance. Impulse excitation provides an alternative to destructive testing methods, enabling repeated measurements and crack detection.
Strength Testing Fundamentals
For cement products, compressive strength and tensile strength are the most important mechanical tests during:
- Mix design development
- Post-production quality checks
- Material qualification
Tensile Strength Significance
Tensile strength reveals cohesion between cement particles and proves critical since concrete structures face vulnerability to tensile cracking from:
- Dynamic loading
- Temperature changes
- Shrinkage stresses
Research indicates tensile strength typically represents roughly 10% of compressive strength.
Impulse Excitation Technique
The technique offers an alternative to indirect testing methods like split cylinder and flexure tests. IET measures resonant frequencies to calculate:
| Property | Relevance |
|---|---|
| Young’s modulus | Stiffness indicator |
| Shear modulus | Structural integrity |
| Poisson’s ratio | Material characterization |
| Sound speed | Quality correlation |
Standards Compliance
The method follows established standards:
- ASTM E 1876
- BS 1881-209
Once correlated with breaking strength data, this approach offers time savings through straightforward setup and physics-based reliability.
Durability Assessment
Freeze-Thaw Resistance
European standard CEN/TR 15177:2006 covers freeze-thaw methods:
- CIF-test
- Slab-test
- Beam test
North America typically uses ASTM C666/C666M-15.
IET enables tracking of stiffness degradation through repeated freeze-thaw cycles without destroying samples.
Microcracking Detection
The system measures bending and torsional resonant frequencies alongside damping values. The detection principle:
- Cracks absorb higher-frequency vibrations
- Damping increases in damaged material
- Frequency shifts indicate stiffness loss
Damping measurements distinguish cracked from intact products, enabling:
- Early damage detection
- Quality sorting
- Service life prediction
Ready to Get Started?
Contact us to discuss your requirements and see how IET can help.