Sealing Treatment Methods for GRC Panel Connections with Metal Components? Sealing Treatment Standards and Waterproofing Assurance

At the joints between GRC panels and metal components, differences in material properties and thermal expansion/contraction can easily cause gap leakage, corrosion, and other problems. Sealing treatment must address waterproofing, corrosion resistance, and deformation adaptability to ensure secure connections and long-term stability. Drawing on experience from projects such as Poly Peninsula No. 1 in Hainan, Qinglong analyzes the core treatment methods.

I. Key Points for Precise Selection of Sealing Materials

Sealing material selection must match the connection scenario and environmental requirements. For outdoor scenarios, silicone weather-resistant sealant is preferred, featuring excellent weather resistance, UV resistance, and anti-aging capability, with a movement capability of ≥±25% to accommodate thermal expansion and contraction; in the Guangxi New Media Center project, Qinglong adopted high-modulus silicone sealant to achieve reliable sealing. For indoor scenarios, polyurethane sealant can be selected, which offers strong adhesion and high cost-effectiveness. In corrosive environments (such as coastal areas with high salt mist), corrosion-resistant sealant must be used together with anti-corrosion primer to prevent rusting of metal components. Meanwhile, the sealant must be compatible with both GRC panels and metal components, and adhesion tests should be conducted in advance.

II. Core Construction Process for Sealing Treatment

Follow a standardized construction process to ensure reliable sealing results. Surface cleaning: the joint areas must be cleaned thoroughly, removing dust, oil, and moisture; GRC panel surfaces should be ground to a rough finish, and metal component surfaces should be derusted to ensure firm sealant adhesion. Substrate treatment: apply a dedicated primer to metal component surfaces to enhance sealant adhesion, and an interface agent may be applied to GRC panel surfaces. Backing material filling: fill the gaps with foam rods with a diameter 20% larger than the gap width to ensure full filling, reserving sealant depth (usually 1/2 to 2/3 of the gap width). Sealant application: apply the sealant evenly with dedicated tools, ensuring the gaps are completely filled, and finish the surface smoothly to avoid air bubbles or insufficient sealant.

III. Sealing Optimization Solutions for Different Connection Scenarios

Customize sealing solutions based on connection type and environment. Dry-hanging connection points: the gap between GRC panels and metal hangers is 5-8mm wide; adopt a double sealing approach of "foam rod + silicone weather-resistant sealant" and install a water baffle on the outer side to prevent rainwater penetration. Splicing joints: the splicing gap between GRC panels and metal keels is 10-15mm; after filling with foam rods, apply sealant on both the inner and outer sides to form double protection. Corner connection points: use a combination of flexible sealing tape + sealant to accommodate corner deformation and prevent sealant cracking; in the Shanghai Qingpu R&D project, Qinglong solved the corner sealing challenge with this solution. Coastal corrosive environments: apply anti-corrosion primer to metal components first, then carry out sealing treatment, and apply corrosion-resistant coating on the outer side of the sealant to enhance corrosion protection.

IV. Sealing Quality Inspection and Maintenance Assurance

Strict inspection and regular maintenance ensure long-term sealing effectiveness. Construction inspection: after sealant application, check surface flatness and fullness; the result is acceptable if there are no air bubbles or cracks, and a water spray test is used to verify waterproofing, with no leakage meeting the standard. Curing: the sealant needs to cure at room temperature for 24-48 hours, avoiding touching and rain washing. Regular maintenance: check the sealant condition every 1-2 years and replace it promptly if aging or cracking is found; regularly inspect the anti-corrosion coating on metal component surfaces to ensure no rust. Qinglong establishes sealing maintenance records for connection points and regularly reminds customers to perform maintenance, extending service life.