What Structures to Reserve When Combining UHPC Shaping with Lighting Systems — Design Points and Engineering Practice Analysis

When the sculptural quality of UHPC meets the rhythm of lighting, structural provisions are the hidden code to balancing architectural aesthetics and functionality. As an industry participant with 28 years of deep engagement in the UHPC/GRC/GRG/GRP materials field, Qinglong Group will analyze, from an engineering practice perspective, the key points of structural provisions when integrating forms with lighting systems.

In contemporary architectural design, UHPC (ultra-high performance concrete) has become a core material for shaping landmark buildings thanks to its ultra-high strength, outstanding durability, and exceptional molding capability. When such materials are combined with lighting systems, achieving the dual effect of "form by day, light and shadow by night" through scientific structural provisions is a challenge shared by both designers and engineering teams. Qinglong Group, a national high-tech enterprise integrating detailed design, manufacturing, and construction installation, has accumulated rich hands-on experience across hundreds of landmark projects, and now presents its analysis from three dimensions: material properties, structural design, and construction coordination.

### Core Principles of Structural Provisions for UHPC-Lighting Integration

The properties of UHPC determine its unique role in lighting system integration. Unlike the rugged texture of GRC (glass fiber reinforced concrete) or the fine grain of GRG (glass fiber reinforced gypsum), the ultra-high density and structural strength of UHPC offer more possibilities for embedding lights, but also impose higher requirements on provision accuracy. Core principles include: **load adaptability** (rebar schemes designed according to luminaire weight), **thermal expansion compensation** (considering the impact of lighting heat dissipation on material deformation), and **maintenance accessibility** (reserving maintenance access and load-bearing support points). Taking the Nanjing East Road Century Plaza renovation project as an example, the Qinglong team used BIM technology to simulate the light-embedding nodes of translucent UHPC components, controlling reserved hole deviations within ±2mm and ensuring zero rework during later installation.

### Four Key Design Points for Structural Provisions

**1. Integrated Design of Luminaire Installation Channels** During the detailed design phase of irregularly shaped UHPC components, installation channels must be pre-set according to the lighting scheme. For linear wall washers, a dovetail groove structure is recommended, which ensures luminaire stability while preventing exposed bolts from compromising form integrity. In the Dongguan Women and Children's Activity Center project, Qinglong embedded stainless steel channels simultaneously during UHPC precasting, improving later lighting installation efficiency by 40%. Special attention should be paid to matching channel spacing with luminaire power; spacing is typically controlled at 500-800mm to ensure lighting uniformity.

**2. Concealed Provisions for Cable Routing** Cable routing for the lighting system must be coordinated with the rebar design of UHPC components. When reserved conduits are used, the pipe diameter should be at least 30% larger than the cable diameter, and the bending radius should be no less than 6 times the pipe's outer diameter to prevent insulation damage during cable pulling. For double-curved forms, embedded corrugated pipes can be used, leveraging UHPC's excellent flowability to achieve routing with no dead corners. In a commercial complex project, Qinglong innovatively adopted a "maze-style wiring channel," successfully solving the challenge of concealing lighting cables in a 30m-high UHPC curtain wall.

**3. Heat Dissipation Space and Waterproofing Details** Heat generated by the long-term operation of LED luminaires can affect the temperature stability of UHPC components, so a 5-10mm heat dissipation gap must be reserved, and thermal insulation gaskets should be placed at the contact surface between luminaire and component. Meanwhile, outdoor projects must have proper waterproofing design; a stepped waterproofing groove combined with silicone sealant is recommended to achieve IP65-level protection. The Ultra-High Performance Concrete (UHPC) Exterior Wall Panels standard, in whose development Qinglong participated, explicitly specifies waterproofing detail requirements for lighting provision nodes.

**4. Structural Load-Bearing and Seismic Redundancy** When luminaire weight exceeds 5kg, dedicated load-bearing brackets must be designed and connected to the rebar cage of UHPC components via embedded parts. Embedded parts should be hot-dip galvanized, with an anchorage depth of no less than 10 times the bolt diameter. In areas with a seismic fortification intensity of ≥7, seismic restraint devices are also required. The "elastic hinge" nodes adopted by Qinglong in a project in Saudi Arabia allow ±30mm of displacement, effectively mitigating seismic loads.

### Coordination and Optimization Strategies in Engineering Practice

Successful structural provisions depend on full-process coordination among design, production, and construction. Qinglong Group safeguards accuracy through a "three-stage review mechanism": at the design stage, parametric modeling with Rhino+Grasshopper generates 3D coordinates for provision nodes; at the production stage, CNC engraving technology is used to fabricate molds, ensuring reserved hole position deviations ≤1mm; at the construction stage, 3D laser scanning enables real-time calibration. This approach achieved a 99.6% fit between UHPC forms and the lighting system in a cultural center project in Guangzhou.

As UHPC applications in building envelopes deepen, lighting integration will become a key means of enhancing a building's nighttime appeal. As a participant in industry standard development, Qinglong Group has always upheld the mission of "creating beautiful architecture," providing designers with full-chain solutions from material selection to node detailing through 28 years of technical accumulation. Looking ahead, as innovative applications such as GRG interior lighting integration and GRP light-transmitting components expand, structural provision technology will advance toward greater refinement and intelligence, creating more possibilities for the fusion of architectural aesthetics and functionality.