What Standard Should GRC Panel Impact Resistance Meet? Safety Resilience and Qinglong Group Resilience Standards

The impact resistance of GRC panels is a key safety indicator for their use as building envelope and decorative materials, especially in areas with dense pedestrian activity or locations prone to accidental impact. It is typically evaluated in accordance with the standard "Glass Fiber Reinforced Cement (GRC) Decorative Products" (JC/T 940-2022), with the core indicator being performance under the "ball drop impact test". Qinglong Group's internal control standard specifies: for general decorative panels, when a 1kg steel ball is dropped freely from a height of 1m onto the panel surface, there should be no cracks or spalling on the back; for areas with higher safety requirements (such as kindergartens and hospital corridors), we require panels to pass more stringent impact tests. In an interior fit-out project for a children's activity center in Nanning, our GRC wall panels successfully passed an impact test with a 1.5kg steel ball dropped from a height of 1.2m, ensuring children's safety during activities. Impact resistance embodies GRC's tough safety philosophy of "cracking without shattering".

Standard Ball Drop Impact Test Method

According to JC/T 940, a specimen measuring no less than 400mm×400mm is simply supported on all four sides, and a 1kg steel ball is dropped freely from a height of 1m to strike the central area of the specimen. After the test, both the impact face and the back of the specimen are inspected and the damage condition is recorded. The standard classifies results as "no cracks", "cracks but no penetration", "cracks on the back", and so on; high-quality products should achieve "no cracks" or "only slight cracks on the impact face".

Key Factors Affecting Impact Resistance

Impact resistance mainly depends on the fiber content, fiber length, distribution uniformity, and matrix toughness. Qinglong GRC uses precise fiber proportioning (3-5% by volume) and robotic spraying technology to ensure a uniform three-dimensional random distribution of fibers, forming an efficient load transfer network. Adding polymer emulsions (such as acrylic emulsion) can also significantly improve matrix toughness, thereby enhancing impact resistance.

Differentiated Requirements for Different Application Scenarios

Indoor walls, ceilings, and other areas with dense foot traffic place high demands on impact resistance. Lower sections of building exterior walls (such as the ground floor) should also take impact resistance into account. For these locations, we increase the fiber content beyond the standard level, or increase panel thickness and add stiffening ribs at the design stage. In the interior fit-out of a metro station in Shenzhen, we adopted a high-toughness GRC formulation to ensure the safety and durability of public spaces.

Synergy with Other Properties

Impact resistance is not an isolated indicator; it must be considered in conjunction with flexural strength, durability, and other properties. By optimizing the mix proportion and process, toughness can be significantly improved without sacrificing other properties. Our laboratory can carry out specialized impact toughness testing and formulation optimization tailored to the needs of specific projects.

Therefore, evaluating the impact resistance of GRC panels should not rely on perception alone, but on standard test methods and data. Through strict material control and scientific testing and verification, Qinglong Group ensures that its products meet or even exceed safety requirements for use.