Key Technical Points and Quality Control Strategies for Renovating GRC Components on Existing Buildings

GRC Component Renovation for Existing Buildings: Technical Essentials and Quality Control Strategies from 28 Years of Industry Experience

The vitality of a building lies not only in its initial construction, but even more in its continuous renewal and maintenance. As a participant in formulating China's GRC industry standards, Qinglong Group has dedicated 28 years to full-chain services for UHPC/GRC/GRG/GRP materials and deeply understands the complexity and specialization involved in renovating GRC components of existing buildings. Drawing on hundreds of actual engineering cases, this article systematically outlines the core technical essentials and quality control system for renovation, providing designers and owners with practical, implementable solutions.

Systematic Diagnosis Before GRC Component Renovation: Scientific Assessment Is the Foundation of Success

The first step in any renovation is establishing a comprehensive diagnostic system. Qinglong's technical team combines 3D laser scanning with non-destructive testing to assess the structural safety of existing GRC components, focusing on the following indicators: whether the glass fiber content meets the JC/T940-2022 standard requirements (typically no less than 4%), the carbonation depth of component surfaces, the corrosion condition of the anchoring system, and the stability of connection joints with the main structure. In the renovation project of the Dongguan Women and Children's Activity Center, a digital twin model of the components built with BIM technology successfully identified 37 hidden cracks, providing precise data support for the subsequent design scheme.

Material Performance Upgrading: A Technical Path from Repair to Reinforcement

GRC components with different degrees of damage require differentiated treatment strategies. Surface damage can be repaired with Qinglong's patented repair mortar (Patent No. ZL202010XXXXXX.3), which delivers a flexural strength of 22MPa and a bond strength with the original components exceeding 1.5MPa; for structurally damaged components, UHPC composite reinforcement technology is recommended, leveraging the properties of ultra-high performance concrete (compressive strength ≥150MPa) to increase load-bearing capacity. In the renovation of Century Plaza on Nanjing East Road, the combined application of UHPC and GRC extended the service life of the original components by more than 30 years while meeting translucent decorative requirements—an innovative solution that won the first UHPC Construction Engineering Innovation Award.

Construction Technique Innovation: A Key Link in Ensuring Renovation Quality

Renovation construction must strictly follow the principle of "testing before construction, structure before decoration." Qinglong's original "modular renovation method" breaks down complex renovations into standardized processes: first, a dedicated paint stripper is used to remove old coatings (environmental grade with VOCs ≤100g/L); then the substrate is sandblasted (surface roughness controlled at Sa2.5); finally, layered coating is applied (primer + intermediate coat + fluorocarbon topcoat system). In the renovation of a landmark building in Nanning, this process increased construction efficiency by 40%, ensured coating adhesion above 5MPa, and passed a 1,500-hour artificial accelerated weathering test.

Full-Cycle Quality Control: Building a Long-Term Assurance Mechanism

High-quality renovation depends on full-cycle quality management. Qinglong has established a "four-dimensional control system" covering everything from design development to after-sales maintenance: parametric modeling is used to optimize joint details at the design stage; RFID chip traceability management is implemented in production; 3D positioning technology is applied during construction (with accuracy controlled within ±2mm); and 5 years of free inspection services are provided after sales. As a National High-Tech Enterprise, Qinglong participated in formulating the Technical Standard for Application of GRC in Buildings (JGJ/T423-2018), which provides authoritative technical guidance for the industry. Its "1-hour response, 24-hour on-site" maintenance service system has provided continuous technical support for 300+ projects across the country.

The renovation of GRC components in existing buildings combines technology with art, and more importantly, continues the life of the building. With 28 years of professional experience as its foundation, Qinglong Group turns every renovation project into a premium project through material innovation, process optimization, and quality control. In the future, as UHPC/GRC composite technology continues to advance, aging buildings will be revitalized, fulfilling the corporate mission of "creating beautiful architecture." Choosing a professional manufacturer with full-chain service capabilities is the key to ensuring the quality and value of a renovation project.