Non Shrink Grout Strength and Specifications
Non shrink grout is a high-performance construction material designed to deliver consistent strength, dimensional stability, and reliable load transfer in critical applications. Its strength and technical specifications define where and how it should be used, making it essential for engineers and contractors to understand these parameters clearly. This guide explains the typical strength levels and key specifications of non shrink grout used in structural and industrial projects.
What Defines the Strength of Non Shrink Grout?
The strength of non shrink grout is primarily determined by its compressive strength, which indicates how much load the grout can safely withstand after curing. Unlike ordinary cement grout, non shrink grout is engineered to achieve higher and more predictable strength while maintaining full contact with surrounding surfaces.
- Measured in MPa (megapascals)
- Tested at specific curing ages
- Directly related to load-bearing performance
Typical Compressive Strength Ranges
Non shrink grout is available in different strength grades to suit various applications.
Standard Grade Non Shrink Grout
- Compressive strength: 20–30 MPa at 28 days
- Used for light structural and general grouting
- Suitable for void filling and non-critical bases
Structural Grade Non Shrink Grout
- Compressive strength: 30–40 MPa at 28 days
- Used for column bases and anchor bolts
- Common in commercial construction projects
High Strength Non Shrink Grout
- Compressive strength: 40–60 MPa or higher at 28 days
- Used for heavy machinery and industrial installations
- Designed for high static and dynamic loads
Strength Development Over Time
Non shrink grout gains strength progressively as it cures.
- 1 day: Early handling strength
- 3 days: Rapid strength development begins
- 7 days: Majority of design strength achieved
- 28 days: Full rated compressive strength reached
Some rapid-hardening grouts achieve high early strength within 24 hours.
Key Technical Specifications of Non Shrink Grout
Apart from strength, several specifications define grout performance.
Flow Characteristics
- Flowable, plastic, or stiff consistency options
- Designed to fill gaps without vibration
- Controlled flow without segregation
Volume Stability
- Zero shrinkage or slight controlled expansion
- Maintains full contact after curing
- Prevents void formation under base plates
Setting Time
- Initial set varies based on formulation
- Rapid-setting options available for fast-track projects
- Allows sufficient working time for placement
Bond Strength
- Strong adhesion to concrete and steel
- Improves load transfer efficiency
- Reduces risk of debonding under load
Durability
- Resistant to cracking and settlement
- Performs well under vibration and cyclic loads
- Suitable for indoor and outdoor applications
Standard Packaging and Mixing Guidelines
Most non shrink grouts are supplied as dry, pre-mixed powders.
- Common packaging: 25 kg bags
- Water requirement varies by consistency
- Mixing must follow recommended ratios strictly
Incorrect mixing directly affects strength and performance.
Matching Strength and Specifications to Application
Choosing the correct grout depends on project requirements.
- Light equipment: Standard grade grout
- Columns and anchors: Structural grade grout
- Heavy machinery: High strength grout
Over-specifying increases cost, while under-specifying risks failure.
Common Specification Mistakes on Site
Avoiding these mistakes ensures rated performance.
- Selecting grout based on price only
- Ignoring required compressive strength
- Adding excess water during mixing
- Loading grout before strength gain
Importance of Following Specifications
Strict adherence to specifications ensures safety and durability.
- Ensures structural integrity
- Improves long-term performance
- Reduces maintenance and repair costs
Frequently Asked Questions (FAQ)
1. Is higher strength always better?
No, strength should match the load and application requirements.
2. Can specifications vary by brand?
Yes, always refer to product datasheets for exact values.
3. Does flow affect strength?
Flowable grout may have slightly lower strength but remains within design limits.
4. Can strength be tested on site?
Yes, cube testing can verify compressive strength.
5. Do specifications change with temperature?
Temperature affects setting time and strength development.
Raltro
Raltro is a construction materials knowledge platform focused on simplifying technical specifications for practical site use. By clearly explaining non shrink grout strength levels, performance parameters, and selection criteria, Raltro helps engineers, contractors, and site professionals match grout specifications to real project demands, avoid misapplication, and achieve reliable, long-term structural performance.