What is a Cube Testing Machine
A Cube Testing Machine is a hydraulic or electromechanical device used to measure the compressive strength of concrete cubes in accordance with standards like ASTM C39 and ISO 7500-1. It determines the load-bearing capacity of 150mm or 100mm concrete specimens.
History of Cube Testing Machine
Developed in the early 20th century alongside reinforced concrete construction, early lever-type machines evolved into hydraulic systems by the 1930s. Digital load cells and computerized controls became standard in the 1980s. Modern machines now feature automated data logging and AI-powered failure pattern analysis.
Purpose of Cube Testing Machine
Verifies concrete's designed compressive strength (typically 15-100 MPa). Essential for quality control in construction projects, material research, and compliance certification. Helps predict structural performance and identify mix design flaws.
Principle of Cube Testing Machine
Applies gradually increasing axial load to concrete cubes through parallel steel platens. Hydraulic pumps generate force (up to 3,000 kN) while load cells measure resistance. The machine records peak load at failure to calculate compressive strength (Force/Area).
Features of Cube Testing Machine
- High Capacity: 2,000-3,000 kN range for standard testing
- Digital Readout: Real-time load display (0.1 kN resolution)
- Auto-Ranging: Adjusts piston speed based on load
- Safety Guards: Reinforced enclosures for debris containment
- Data Export: USB/Bluetooth connectivity for test reports
Types of Cube Testing Machines
- Manual Hydraulic: Hand-operated pumps for basic testing
- Automatic Servo: Computer-controlled stress rates
- Universal Testers: Multi-purpose machines for tension/compression
- Portable Units: Field-testing models with 1,000 kN capacity
- High-Strain Rate: For dynamic loading simulations
Precautions for Using Cube Testing Machine
- Cube Preparation: Ensure proper curing (28-day standard)
- Alignment Check: Center specimen between platens
- Load Rate Control: Maintain 0.2-0.4 MPa/s as per standards
- Overload Prevention: Set automatic stop at 90% expected failure
- Maintenance: Monthly calibration with proving rings
Things to Consider When Purchasing
- Capacity: Match to concrete grade requirements (e.g., 2,000 kN for 50 MPa concrete)
- Accuracy: ±1% full-scale deviation maximum
- Compliance: EN 12390-4 or BS 1881-115 certification
- Platen Size: Minimum 200×200mm for 150mm cubes
- Software: Integrated reporting per ACI 214/BS EN 12390-3
Terms of Cube Testing Machine
- kN Rating: Kilonewton capacity (1 kN = 224.8 lbs)
- Stress Rate: 0.15-0.35 MPa/s as per IS 516
- Platen Parallelism: ≤0.02mm deviation across surfaces
- Calibration: Annual traceability to NIST standards
- Crosshead Movement: 1-5mm/min during testing