Application Of Glass Fiber Chopped Felt In Grc Products

(2) Overview of Chopped Strands and GRC Materials

1.Definition of GRC Materials

   GRC materials, fully known as Glass-fiber Reinforced Concrete, are a composite material defined as a new type of building material formed by combining alkali-resistant glass fibers as reinforcement with cement mortar matrix through specific processes. This material integrates the high strength and high modulus of glass fibers with the good moldability and durability of cement mortar, thus exhibiting excellent mechanical properties, lightweight characteristics, and good adaptability to various environmental conditions. GRC materials have broad application prospects in fields such as architecture, sculpture, and landscaping, meeting diverse requirements for material strength, toughness, durability, and aesthetics.

2.Basic Components Typically Found in GRC Materials

   – Cement: This is the matrix material in GRC that provides primary structural support. Common types of cement include fast-setting sulfoaluminate cement, low-alkali sulfoaluminate cement, ordinary Portland cement, and white Portland cement. The choice of these types will affect the performance characteristics of GRC materials.  

   – Alkali-resistant Glass Fibers: As a reinforcement material, alkali-resistant glass fibers play a vital role in enhancing the strength and toughness of GRC materials. They must resist erosion from the alkaline environment generated during cement hydration. Alkali-resistant glass fibers come in various forms such as roving, chopped strands, and mesh fabrics that can be selected based on specific needs.  

   – Polymers: To improve the performance of GRC materials, a suitable amount of polymer is usually added. Commonly used polymers include acrylic copolymer emulsions which enhance adhesion, water resistance, and durability.  

   – Additives: Depending on specific needs, certain additives may be selectively included such as high-efficiency water reducers, plasticizers, retarders, accelerators, antifreeze agents, rust inhibitors, etc. These additives can adjust the setting time of cement mortar or improve construction performance or increase material strength.  

   – Other Auxiliary Materials: To further enhance the performance of GRC materials, some volcanic ash reactive materials or other lightweight aggregates may be selectively added to improve comprehensive properties such as strength, impermeability, and durability.

In summary, GRC materials are a new type of building material composed of cement, alkali-resistant glass fibers, polymers, additives, and other auxiliary materials combined through specific processes. The reasonable selection and proportioning of these components significantly impact the performance and application effectiveness of GRC materials.

3.Definition of Glass Fiber Chopped Strand Mat

   Glass fiber chopped strand mat (CSM) is a nonwoven glass fiber product made from continuous glass fiber strands cut to a specific length (usually 50 mm), uniformly distributed in a random orientation and bonded with powdered polyester binder (or emulsion binder). It is mainly classified into medium-alkali or non-alkali glass fiber nonwoven products. This material features uniform mass per unit area without stains or debris defects, moderate hardness, good flexibility, easy complete impregnation with minimal bubbles in products, and good processability. It is widely used in hand lay-up molding processes for reinforcing unsaturated polyester resin, vinyl resin, epoxy resin, phenolic resin via winding molding or centrifugal casting methods. End products include various fiberglass products such as automotive accessories, hulls for boats, insulation materials for transformers, sanitary ware fixtures, seating units, chemical corrosion-resistant pipes and tanks, cooling towers, water tanks, wind turbine blades, architectural components and furniture.

The packaging methods for glass fiber chopped strand mats vary; they are typically wound around paper tubes with an inner diameter of 90 mm wrapped in plastic film and packed in cardboard boxes or kraft paper bags for vertical or horizontal placement. During transportation, they can be shipped loose or on pallets. When storing them should be kept in a dry place away from moisture and rain while avoiding sunlight exposure and fire sources. It is recommended that storage temperature be controlled between 15°C to 35°C with humidity between 35% to 65%. Overall, glass fiber chopped strand mat is a high-performance product widely used.

4.Specific Enhancement Mechanism of Matelas de fibres de verre à brins coupés on GRC Performance

   The enhancement mechanism of Glass fiber chopped strand mat in GRC (Glass-fiber Reinforced Concrete) reflects a comprehensive effect. The fibers in the chopped strand mat are evenly dispersed within the cement matrix and form tight bonds with it. This dispersion and bonding state allow fibers to effectively bear and distribute external loads thereby improving the overall strength of GRC materials. When external forces act on GRC materials, fibers within the chopped strand mat can bridge across cracks to prevent further crack propagation while also constraining deformation and cracking in the matrix under stress conditions. This physical enhancement significantly increases GRC’s tensile strength, flexural strength, and impact resistance.

Furthermore, the interfacial bond strength between glass fiber chopped strand mat and cement matrix is also a key factor affecting GRC performance. By optimizing production processes and using suitable bonding agents can enhance bond strength between fibers and matrix further improving GRC’s performance. Although glass fibers may undergo hydrolysis under alkaline conditions when selecting glass fibers and cement matrices their chemical compatibility should be considered to avoid adverse chemical reactions.

In addition to physical enhancement effects，the glass fiber chopped strand mat may also chemically react with the cement matrix to form new chemical bonds that further strengthen adhesion between fibers and matrix enhancing comprehensive performance.