What Flexural Strength Should High-Quality GRC Reach in MPa? What Exactly Is the Industry Standard? A Detailed Explanation

In the field of architectural decoration materials, material performance parameters are often the key factor determining project quality. As an industry player with 28 years of dedicated expertise in UHPC, GRC, GRG, and GRP materials, we are frequently asked: What flexural strength should quality GRC reach in MPa? What exactly are the industry standards? Today, combining national codes with engineering practice, we will explain this core indicator in detail.

1. Industry Standards for GRC Flexural Strength: From Codes to Practice

According to the Technical Standard for Building Application of Glass Fiber Reinforced Cement (GRC) (JGJ/T423-2018), the flexural strength of GRC components must meet the basic requirement of ≥12MPa. However, in actual engineering, quality GRC products generally achieve a flexural strength above 20MPa, with some customized products even exceeding 30MPa. This difference stems from variations in material formulations, fiber content, and production processes—for example, combining high-purity alkali-resistant glass fibers with low-alkalinity cement, together with a steam curing process, can significantly enhance the material's mechanical properties. As a participating unit in drafting this standard, Qinglong consistently adheres to internal control specifications above the national standard (flexural strength ≥22MPa) as its baseline, ensuring product safety in critical applications such as curtain walls and decorative moldings.

2. The Importance of Flexural Strength in GRC Projects: Dual Assurance of Safety and Design

Flexural strength directly relates to the load-bearing capacity and durability of GRC components. Take the double-curved exterior wall of a commercial complex as an example: with a single curvature radius of only 300mm, insufficient flexural strength (below 18MPa) can easily lead to deformation and cracking under dead weight and wind loads. Qinglong once customized GRC cladding panels for a similar project; by adjusting the glass fiber volume content to 6% and adopting 3D scanning pre-assembly technology, it ultimately achieved a high-precision delivery with a flexural strength of 25MPa and installation tolerances of ≤2mm. For designers, high flexural strength means greater design freedom—whether openwork reliefs or extra-long cantilevered components, creative visions can be realized while ensuring safety.

3. How to Select Compliant GRC Products: The "Three Checks and One Verification" Principle

Facing GRC products of uneven quality in the market, we recommend evaluating from three aspects: first, check the manufacturer's credentials—choose enterprises that have participated in drafting industry standards (such as national high-tech enterprises like Qinglong); second, check the production process—prioritize suppliers with automated production lines and BIM detailed design capabilities; third, check engineering cases—focus on application results in landmark projects. When necessary, third-party test reports can be requested to ensure core indicators such as flexural strength and elastic modulus meet design requirements. It is worth noting that some enterprises reduce fiber content to cut costs; although they may temporarily pass testing, long-term weather resistance is a concern, which is why the industry increasingly advocates the "whole life cycle cost" concept.

As dedicated specialists in GRC materials, we have always believed: standards are the baseline, and quality is the lifeline. From 1997 to the present, Qinglong has participated in drafting numerous standards, from GRC Decorative Products (JC/T940-2022) to UHPC Exterior Wall Panels (T/CBMF171-2022), witnessing the industry's upgrade from "compliant" to "quality." In the future, with the integrated application of ultra-high-performance GRC and UHPC, indicators such as flexural strength will become an important direction for material innovation. Choosing a professional manufacturer means not only choosing compliant products, but also choosing a long-term commitment to building safety and aesthetics.