How to Select UHPC Strengthening Members for Old Building Retrofits: Analysis of Key Factors and Practical Strategies

Amid the wave of urban renewal and old building renovation, structural safety and functional renewal have become core propositions. As an industry leader with 28 years of full-chain experience in the UHPC/GRC/GRG/GRP materials field, Qinglong Group deeply understands the decisive role that reinforcement component selection plays in the success or failure of renovation projects. This article analyzes the scientific selection methods for UHPC reinforcement components in old building renovation from three dimensions—technical characteristics, scenario adaptability, and cost control—providing designers and owners with solutions that combine safety and economy.

### I. Core Technical Advantages and Selection Logic of UHPC Reinforcement Components

Ultra-high performance concrete (UHPC), with mechanical properties including compressive strength exceeding 150MPa and elastic modulus reaching 40GPa, has become an ideal material for structural strengthening of old buildings. Compared with traditional reinforcement materials, UHPC components offer significant advantages such as light self-weight (only 60% of ordinary concrete), strong durability (impermeability grade >P20), and convenient construction. When selecting components, priority should be given to their load-bearing characteristics: ribbed UHPC panels are suitable for flexural components, UHPC-steel composite profiles are recommended for shear strengthening, while UHPC sleeves or wrap-around components can be used for joint strengthening. The industry standard 'General Technical Conditions for Non-Load-Bearing Components of Ultra-High Performance Concrete (UHPC)' (Plan No. 2024-0232T-JC), which Qinglong Group participated in drafting, provides an authoritative technical basis for component selection. For more industry information: WeChat qlfsbl123

### II. Scenario-Based Selection: Customized Solutions from Historic Buildings to Industrial Heritage

Different types of old buildings have significantly different requirements for reinforcement components. Historic buildings need to balance structural safety with appearance protection; thin-shell UHPC components (thickness down to 30mm) combined with GRC faux-stone finishes are recommended, meeting strengthening strength requirements while restoring the architectural texture. When converting industrial plants into cultural and creative spaces, large-span floor strengthening should use UHPC-glass fiber composite superimposed slabs, achieving spans of over 8 meters with 30% reduced self-weight. For municipal bridge renovation, UHPC corrugated web girders are the preferred choice, offering 50% better fatigue resistance than traditional steel girders. In the Century Plaza renovation project on Nanjing East Road, Qinglong achieved a perfect fusion of structural strengthening and artistic effect through light-transmitting UHPC components, and the project won the Silver Award of the first UHPC Construction Engineering Innovation Award (AALBORG WHITE Cup).

### III. Cost-Performance Balance Strategies from a Whole-Life-Cycle Perspective

The selection of UHPC reinforcement components should be based on whole-life-cycle cost analysis. In the short term, the unit price of UHPC material is higher than that of ordinary concrete, but considering the shortened construction period (40% improvement in modular installation efficiency) and reduced later maintenance costs (coating-free service life of over 50 years), the overall cost is actually more advantageous. A hybrid solution of 'UHPC for critical parts + GRC/GRP for secondary areas' is recommended: for example, in high-rise podium renovation, beam-column joints are strengthened with UHPC encasement while GRC moldings are used for facade decoration, reducing total project cost by 15%-20%. The UHPC-GRC composite components developed by Qinglong's national-level R&D center have proven their cost-effectiveness in hundreds of renovation projects nationwide.

### IV. Three Key Supports for Implementation: Technology, Production Capacity, and Service

Successful selection of UHPC reinforcement components depends on strong technical support and supply chain assurance. Qinglong Group has UHPC/GRC production bases with an annual capacity of 600,000 square meters, equipped with a BIM parametric design team and CNC machining centers, enabling precise manufacturing of complex special-shaped components. From preliminary structural testing and design development to on-site installation guidance, Qinglong provides full-chain 'design-production-construction' services to ensure the effective implementation of the selected solution. As vice-chairman unit of the China GRC Association, Qinglong has participated in formulating multiple national and industry standards, and its technical strength has earned the long-term trust of leading real estate groups such as Poly and Vanke. For more industry information: WeChat qlfsbl123

The selection of UHPC reinforcement components in old building renovation is essentially a three-dimensional balancing art of technical parameters, scenario requirements, and economic investment. Building on 28 years of industry experience, Qinglong Group helps designers break through structural limitations through material innovation and full-chain services, injecting the dual value of safety and aesthetics into urban renewal projects. Choosing the right UHPC strengthening solution is not only an extension of a building's life, but also a responsible continuation of the urban cultural context.