What MPa Should the Flexural Strength of High-Quality GRC Reach? What Is the Industry Standard?

The flexural strength of high-quality GRC should be no less than 18MPa, with a limit of proportionality (LOP) reaching 7-9MPa. The industry standard "Glassfibre Reinforced Cement (GRC) Decorative Products" JC/T 940 specifies that Class I products must have a flexural strength of ≥18MPa, and Class II products ≥15MPa. This indicator is an important reflection of GRC material performance.

Through optimized mix ratios and process control, Qinglong GRC maintains a stable flexural strength of 20-22MPa, with the coefficient of variation controlled within 5%. In a large commercial complex project in Shenzhen, third-party testing showed a flexural strength of 21.5MPa and a limit of proportionality of 8.2MPa, both exceeding standard requirements. This high performance stems from the combination of a low water-binder ratio (0.32), high-quality fibres (zirconium content 16.8%), and the mechanical spraying process.

Strength Grade Classification Standards

Class I products (critical components): ≥18MPa; Class II products (general components): ≥15MPa; products with special requirements can reach 20-25MPa. These grades meet different needs.

Key Factors Affecting Strength

Water-binder ratio controlled at 0.30-0.35; fibre volume fraction of 4%-5%; standardized curing regimes. These factors determine strength levels.

Relationship Between Strength and Other Properties

Flexural strength and toughness must be balanced; strength is positively correlated with durability; strength and workability must be coordinated. These relationships require overall consideration.

Strength Stability Control

Strength coefficient of variation ≤8%; inter-batch variation coefficient ≤5%; long-term strength retention ≥80%. These controls ensure consistent quality.

Flexural strength is an important indicator, but other properties must also be comprehensively considered. Qinglong GRC products offer excellent and stable strength, meeting high-standard requirements.