Case 3: Southeast Asia Theme Park GRC Sculpture Project

Why Choose GRC Spraying Machine for Decorative Element Production?

Glass Fiber Reinforced Concrete (GRC) is a new architectural decorative material using alkali-resistant glass fiber as reinforcement and cement mortar as matrix, featuring lightweight, high strength, rich shapes, and good durability. It is widely used in building facades, interior decoration, and architectural restoration.

Handan Chengyuan Technology supplies GRC spraying machine, using screw pump to convey cement mortar, pneumatic cutter to continuously convey glass fibers, dual-material mixed spraying, adjustable fiber length (10-50mm), precise fiber content control (3%-8%), uniform spraying thickness, fine surface texture, meeting production needs of various complex-shaped GRC decorative elements.

GRC Mix Ratio Design and Performance Indicators

Main Performance Indicators of GRC

GRC Spraying Machine Production Process and Operation Key Points

1. Production Process Flow

1. Mold preparation: Check if the mold surface is clean and smooth, apply special mold release agent to ensure smooth demolding and surface quality. For complex shape molds, check if mold splicing is tight to prevent slurry leakage.
2. Mortar preparation: Weigh cement, quartz sand, silica fume and other raw materials according to the mix ratio, first dry mix for 2 minutes to mix evenly, then add water and water reducer, mix for 3-5 minutes until the mortar is uniform and fluidity meets requirements (flow spread 300-400mm).
3. Fiber preparation: Check if glass fibers are dry and free of clumps, adjust fiber cutting length (generally 10-30mm) to ensure smooth fiber delivery without blockage.
4. Spray forming: Start the spraying machine, first spray a layer of pure mortar (thickness 2-3mm) as the face layer, then simultaneously spray mortar and glass fibers in layers, each layer 3-5mm thick, until the design thickness is reached. During spraying, the nozzle should be perpendicular to the mold surface, 0.5-1.0m away, moving uniformly to ensure uniform thickness.
5. Roll compaction: After each layer is sprayed, use a roller or scraper to roll and compact, removing air bubbles, ensuring full bonding of fibers and mortar, improving density and surface quality.
6. Surface finishing: After reaching the design thickness, perform surface finishing to ensure the surface is flat and smooth. For components requiring special texture, embossing or sandblasting can be performed on the surface.
7. Curing and demolding: After forming, cure components in natural environment for 24-48 hours (temperature ≥15°C), demold when strength reaches 50%-70% of design strength. After demolding, continue moist curing for 7-14 days to ensure continuous strength development.
8. Post-treatment: Demolded components undergo post-treatment processes such as patching, grinding, cleaning, waterproofing, then surface coating or dyeing according to design requirements.

2. Equipment Operation Key Points

• Mortar pumping: The delivery pressure of the screw pump should be controlled at 0.3-0.6MPa, and the delivery volume adjusted according to component size and production efficiency (generally 2-5m³/h). Mortar should be continuously supplied to avoid flow interruption causing uneven spraying.
• Fiber delivery: The glass fiber delivery speed should match the mortar delivery volume to ensure accurate fiber content (3%-5%). Fiber cutting length should be adjusted according to component thickness and shape complexity, generally short fibers (10-20mm) for thin-walled components and long fibers (20-30mm) for thick-walled components.
• Spraying angle: The nozzle should be as perpendicular to the mold surface as possible (75°-90°), avoiding oblique spraying that causes inconsistent fiber orientation and mortar rebound. For complex shapes and internal corner areas, appropriately adjust spraying angle and distance to ensure dense filling.
• Spraying distance: The distance between the nozzle and mold surface should be controlled at 0.5-1.0m. Too close causes mortar accumulation and uneven thickness; too far causes high rebound and poor fiber dispersion.
• Layered spraying: Spraying should be done in layers, each layer 3-5mm thick, avoiding one-time excessive spraying that causes sagging and insufficient density. After each layer is sprayed, promptly roll and compact before spraying the next layer.

3. Quality Control Key Points

• Raw material control: Cement should meet GB 175 requirements, quartz sand should be clean with reasonable grading, glass fibers should be alkali-resistant glass fibers (ZrO₂ content ≥16%), water reducer should have good compatibility with cement.
• Mix ratio control: Strictly weigh raw materials according to the mix ratio, water-binder ratio controlled at 0.30-0.35, fiber content controlled at 3%-5%. Each batch should measure mortar flow spread and setting time to ensure workability meets requirements.
• Thickness control: Use needle measurement or slicing method to check spraying thickness, checking at least 3 points per 10m², thickness deviation not exceeding ±1mm, minimum thickness not less than 90% of design thickness.
• Fiber content testing: Use ignition or water washing method to determine fiber content of GRC components, testing at least 1 group per 500m², fiber content deviation not exceeding ±0.5% of design value.
• Strength testing: At least 1 set of flexural specimens and 1 set of compressive specimens should be retained per shift, tested after 28 days of standard curing, flexural strength ≥12MPa, compressive strength ≥50MPa.
• Appearance inspection: Component surfaces should be flat and smooth, free of cracks, honeycombing, pitting, chipped edges and corners and other defects. Color difference should be uniform without obvious uneven color.