How Should the Thickness of GRC Components at Corner Positions Be Handled?

Thickness treatment of GRC components at corner positions must follow the principles of "strength adaptation, stress dispersion, and shape coordination". Conventional inner corners require a thickness of ≥25mm and outer corners ≥30mm; complex corners require additional stiffening ribs. Through precise design and process optimization, Qinglong has increased the strength of corner components by 40%, and corners in projects such as the Guangxi New Media Center and the Shanghai Qingpu R&D Project show no cracking or deformation.

1. Corner Types and Thickness Baselines: Basic Adaptation Standards

Different corner types have different thickness requirements. Inner corner treatment: internal building corners (such as wall inside corners) are subject mainly to compressive stress; the thickness baseline is 25-30mm, and single-layer GRC is sufficient. In Qinglong's Nanning Nanhu Mingdu project, inner corners are 25mm thick, reinforced with fibreglass mesh, meeting strength requirements. Outer corner treatment: external building corners (such as wall outside corners) face complex forces and must withstand wind loads, impacts, and other external forces; the thickness baseline is 30-35mm, 20% thicker than inner corners. In Qinglong's Guangzhou Xinghewan project, outer corners are 32mm thick with impact strength ≥5kJ/m². Shaped corner treatment: complex shapes such as curved corners and multi-faceted corners require a thickness of ≥35mm to ensure shape stability. The curved corners of Qinglong's Guangxi New Media Center are 35mm thick, with smooth arcs and no deformation.

2. Stiffening Rib Design: Enhancing Corner Load-Bearing Capacity

Stiffening ribs are a key complement to thickness treatment at corners. Stiffening rib placement principle: when a corner span exceeds 1.5m or the load exceeds 5kN/m, stiffening ribs must be installed; rib thickness matches the main corner body, with a width of 2-3 times the thickness. Qinglong's stiffening ribs are ≥60mm wide with spacing ≤1.2m. Rib position: inner corner ribs are placed on the inside of the corner and outer corner ribs on the outside, avoiding any impact on appearance. Qinglong's outer corner ribs adopt a concealed design integrated with the component's shape. Material enhancement: the rib area may have an increased alkali-resistant glass fibre content (0.3-0.5% higher than the main body) or added fibreglass mesh. Qinglong's stiffening ribs achieve a fibre content of 2.5% and flexural strength ≥10MPa.

3. Qinglong's Corner Treatment Process and Quality Control

Process optimization ensures reasonable thickness and good aesthetics at corners. Mould design: corner moulds are produced with integrated CNC machining, avoiding thickness unevenness caused by splicing gaps; Qinglong's mould corner precision is ≤±0.5mm and thickness deviation ≤±1mm. Casting process: corners are cast in layers (each layer ≤20mm) with focused vibration on the stiffening rib areas to ensure compaction; Qinglong's high-pressure vibration (≥2500 times/min) achieves corner compactness ≥2.2g/cm³. Surface treatment: corner surfaces are finished with grinders; the inner corner fillet radius is ≥8mm and the outer corner fillet radius ≥5mm, avoiding stress concentration at sharp edges. After Qinglong's corner fillet treatment, the cracking risk is reduced by 60%. Project case: the GRC curtain wall corners of Shenzhen Longhua Xiangshan Science and Technology Park (span 2.0m), with 35mm thickness plus a double-sided stiffening rib design, withstood strong wind loads after installation without deformation, with appearance coordinated and unified with the main curtain wall.