What Are the Mold Splitting Principles for Complex GRC Shapes?

In the field of modern architectural decoration, GRC (Glass Fiber Reinforced Concrete) has become a core material for shaping complex building skins and artistic components thanks to its outstanding molding capability and material properties. As an industry leader with 28 years of full-chain experience in detailed design, manufacturing, construction installation, and after-sales maintenance of UHPC/GRC/GRG/GRP materials, Qinglong Group deeply understands the decisive role that complex GRC shape parting technology plays in project implementation. This article systematically analyzes the parting principles for complex GRC shapes, providing professional technical reference for designers, owners, and industry peers.

### I. The Core Positioning of Parting Design: Balancing Artistic Shaping and Engineering Feasibility

Parting for complex GRC shapes is not simple “cutting”; it is a systematic engineering process integrating structural mechanics, material properties, and production techniques. When participating in the Dongguan Women and Children's Activity Center (New Site) project (Silver Award of the 1st GRC Construction Engineering Innovation Award, AALBORG WHITE Cup), Qinglong Group used parametric parting technology to decompose the double-curved curtain wall into 128 special-shaped components, achieving a perfect balance between design creativity and construction efficiency. Parting design must prioritize three core objectives: ensuring component strength and safety, optimizing production and installation processes, and controlling the impact of joint treatment on overall aesthetics.

### II. Four Core Principles of Parting for Complex GRC Shapes

#### 1. Structural Safety Principle: Mechanical Performance as the Parting Benchmark

Parting design must first consider the load-bearing characteristics of GRC components. During the detailed design stage, Qinglong Group uses finite element analysis software to simulate stress on the shape, treating stress concentration areas as parting boundaries to prevent components from cracking under self-weight or external loads. For example, in the light-transmitting concrete project of the Century Plaza renovation on Nanjing East Road (Silver Award of the 1st UHPC Construction Engineering Innovation Award, AALBORG WHITE Cup), for special-shaped components with a cantilever length of up to 3.2 meters, the “stress gradient parting method” was adopted, keeping the maximum deflection within L/250, far exceeding industry standards. In addition, parting must ensure that the weight of a single component does not exceed the load capacity limit of hoisting equipment (usually controlled within 500kg), while reserving sufficient anchoring point positions to guarantee the stability of the installation structure.

#### 2. Shape Integrity Principle: Minimizing the Interference of Joints with Visual Effects

For complex shapes such as double-curved surfaces and openwork reliefs, parting must follow the principle of “visual continuity”. Qinglong Group uses BIM technology to build 1:1 digital models, prioritizing parting along the natural texture lines, symmetry axes, or concealed areas of the shape so that joints blend with the design lines. In a parametric skin project for a commercial complex, the “parametric parting algorithm” kept the joint error of 1,200 GRC components within ±2mm, achieving zero-deviation reproduction from design drawings to physical reality. Meanwhile, for exposed joints, waterproofing structures and decorative treatment solutions must be designed at the parting stage to prevent rainwater penetration or material shrinkage from affecting aesthetics later on.

#### 3. Production Feasibility Principle: Adapting to Mold Processing and Process Characteristics

The production of GRC components depends on mold precision, and parting design must fully consider the feasibility and economy of mold making. Qinglong Group's production base in Nanning, Guangxi has an annual capacity of 600,000 square meters, with clear parting standards: parting dimensions for flat components should not exceed 2.4m×1.2m; curved components with a radius of less than 300mm require split molds; openwork shapes need to reserve a demolding draft angle (usually ≥3°). For example, in a GRP special-shaped sculpture project for a theme park, “modular parting” broke down the complex shape into 28 standard modules, raising the mold reuse rate by 40% and cutting production costs by 25%. In addition, parting should avoid sharp-angle structures; corner radii should be ≥5mm to reduce the risk of glass fiber breakage during the molding process.

#### 4. Installation Convenience Principle: Optimizing On-Site Splicing and Positioning Efficiency

Parting design must also take on-site installation conditions into account. During the detailed design stage, Qinglong Group simulates the construction process to ensure that components after parting can be transported and positioned by conventional hoisting equipment. For GRC curtain walls installed at height, “unitized parting” is adopted, pre-assembling multiple components into installation units and achieving “zero-error” splicing through 3D laser scanning positioning technology. In an airport terminal project, this method shortened the installation period by 30% while reducing the risks of high-altitude work. In addition, positioning pin holes and adjustment bolts must be designed at component edges during parting to facilitate on-site fine adjustment and ensure flat joints.

### III. Innovative Practice of Parting Technology: From Experience-Driven to Digitally-Driven

As architectural shapes become increasingly complex, traditional experience-based parting can no longer meet the demand. As a participating compiler of the “Technical Standard for Building Application of Glass Fiber Reinforced Cement (GRC)” (JGJ/T423-2018), Qinglong Group took the lead in integrating Rhino+Grasshopper parametric design and BIM technology into the parting process, achieving rapid iteration and visual verification of parting schemes. By building a parting database, parting experience from similar projects can be quickly retrieved, and parting parameters can be optimized in combination with new material properties (such as the high fluidity of UHPC), providing designers with full-process technical support from creative concept to implementation. For more industry information: +WeChat qlfsbl123

### Conclusion: Parting Technology Is the “Invisible Skeleton” for Implementing GRC Shapes

The parting principles for complex GRC shapes are, in essence, about finding the optimal solution between artistic expression and engineering practice. With 28 years of industry experience and the technical strength of its national-level R&D center, Qinglong Group regards parting design as a key link in project success. Through three-dimensional control of “structural safety as the foundation, shape integrity as the soul, production and installation as the application”, it has helped numerous landmark projects realize their design visions. In the future, with the innovative application of UHPC/GRC/GRG/GRP materials, parting technology will develop toward greater intelligence and precision, injecting new vitality into the architectural decoration industry.