How Should the Anchorage Depth of Exterior Wall GRC Components Be Determined?

# How Should the Anchoring Depth of Exterior Wall GRC Components Be Determined? Industry Professionals Offer Expert Reference

In the construction implementation of exterior wall GRC (Glass Fiber Reinforced Concrete) components, the setting of anchoring depth has long been a key technical point of focus for many designers and project leaders, as it directly affects the firmness of component installation and long-term safety of use, and is also one of the core technical requirements for a project to pass compliance acceptance. As a professional manufacturer with 28 years of full-chain service experience in UHPC/GRC/GRG/GRP, the Qinglong GRC team has participated in the implementation of nearly a thousand GRC projects across China, covering landmarks, commercial complexes, and public buildings. Drawing on the requirements of the current Technical Standard for Building Application of Glass Fiber Reinforced Cement (GRC) JGJ/T423-2018 and frontline construction experience, we outline the logic for determining anchoring depth.

## Core Basis for Determining the Anchoring Depth of Exterior Wall GRC

First of all, it should be made clear that there is no single fixed value for the anchoring depth of GRC components; it must be calculated comprehensively based on multiple parameters: First, the load parameters of the components themselves, including component self-weight, the standard value of wind load in the region, and the local seismic fortification intensity; large-sized special-shaped GRC components also require additional consideration of temporary construction loads and additional stress caused by temperature-induced deformation. Second, the material characteristics of the base wall—concrete substrates, aerated block substrates, and masonry substrates differ considerably in bond strength, so the corresponding anchoring depth requirements will also differ. Third, the material and specifications of the anchors themselves—conventional stainless steel anchors and specialized chemical anchors differ significantly in their effective anchoring depth thresholds. For more industry information: WeChat qlfsbl123

## Reference Values for Conventional Anchoring Depth in Different Scenarios

Based on the implementation experience of a large number of projects, the anchoring depths in conventional scenarios can serve as an initial reference: for ordinary small-sized molding-type GRC components, the effective anchoring depth on concrete substrates should not be less than 80mm; for curtain wall-type GRC exterior wall cladding panels, the corresponding effective anchoring depth is generally no less than 100mm; for components located in high wind pressure regions or areas with a seismic fortification intensity of 8 degrees or above, or special-shaped GRC components weighing more than 50kg per piece, the anchoring depth needs to be increased by more than 20% over the conventional value, together with supplementary anti-detachment reinforcement measures. It should be noted that the above values are for general reference only, and the final figures must be confirmed through structural load verification.

## Common Pitfalls to Avoid in Setting Anchoring Depth

Many projects fall into the misconception that "the deeper the anchoring depth, the safer it is." In reality, excessive anchoring depth may instead cause localized stress concentration in the base wall and actually increase the risk of substrate cracking. At the same time, it is important to distinguish between the total length of the anchor and the effective anchoring depth, avoiding counting the portion of the anchor embedded in the decorative finish or insulation layer as effective anchoring depth, which would result in insufficient actual bond strength. As a participating editor of the national GRC industry standards, Qinglong will issue a complete anchoring plan at the project detailed design stage, taking into account component parameters, the local environment of the project site, and substrate conditions, thereby eliminating installation safety hazards at the source. For more industry information: WeChat qlfsbl123