Cracking, insufficient toughness and poor durability have long plagued the cement product industry. As a high-quality reinforcing material, alkali-resistant glass fiber chopped strands effectively address these pain points, improving the crack resistance, flexural strength and service life of cement products. However, the market is flooded with products of uneven quality and diverse specifications. How to accurately select suitable products has become a core concern for cement product manufacturers. With 24 years of in-depth experience in the glass fiber industry and products exported to 126 countries, Yuni, a professional manufacturer, draws on industry experience and its own product advantages to elaborate on the key points for selecting alkali-resistant glass fiber chopped strands dedicated to cement products, based on customers’ actual needs.
Cement matrices are strongly alkaline. Ordinary glass fibers are prone to corrosion in alkaline environments, resulting in rapid strength degradation and an inability to deliver long-term reinforcement. Therefore, alkali resistance is the primary criterion for selection.
High-quality alkali-resistant glass fiber chopped strands rely on premium raw material formulations and strict process control. Yuni’s alkali-resistant chopped strands adopt a high zirconia (ZrO₂) formulation, with the zirconia content strictly controlled at over 14.5%, and up to 16.5% for high-performance products. This effectively resists erosion by alkaline substances in cement, maintaining stable performance even when embedded in cement matrices for long periods. In addition, we strictly comply with the national standard GB/T 38143-2019, ensuring the mass loss rate of fibers in strong alkaline environments is kept at 3%-8%, far superior to ordinary products. This fundamentally prevents fiber corrosion and failure.
In contrast, some low-cost products on the market use low-zirconium or zirconium-free formulations to cut costs. While they may seem to perform well in the short term, fiber brittleness and a sharp decline in reinforcement effect occur within 3-6 months, ultimately leading to cracking and damage of cement products and increasing corporate maintenance and rework costs.
Fiber diameter and length are key parameters affecting reinforcement efficiency and construction convenience, which must be carefully selected based on the type of cement product and production process.
Fiber diameter directly influences specific surface area and interfacial bonding strength. Fibers that are too thin (<7μm) are prone to breakage and suffer high mixing losses; fibers that are too thick (>17μm) have a small specific surface area, resulting in insufficient bonding with cement matrices and low reinforcement efficiency.
Yuni’s alkali-resistant chopped strands offer a standard diameter range of 7-17μm, suitable for the vast majority of cement product applications. Among them, products with a diameter of 10-14μm are bestsellers. Their specific surface area is 10 times that of steel fibers. One kilogram of fiber provides a bonding interface of over 100 square meters. With a low dosage of 4-6 kilograms per cubic meter, the 28-day flexural strength of cement products can be increased by more than 30%, achieving both light weight and high strength.
Fiber length must match the production process. Excessively long fibers tend to agglomerate and bend, while excessively short fibers have insufficient anchorage and are prone to pull-out. Yuni provides full-range chopped strands of 3mm, 4.5mm, 6mm, 12mm, 18mm and 24mm, meeting the needs of mainstream processes such as premixing and spraying.
3-6mm: Suitable for mortars and thin-walled cement products (e.g., insulation boards, decorative moldings), with good dispersibility, low tendency to agglomerate and easy construction.
12-18mm: Ideal for GRC components, precast wall panels, cement manhole covers and other medium-thick products, offering sufficient anchorage length and remarkable crack-resistant reinforcement effect.
24mm: Designed for high-load cement products (e.g., load-bearing wall panels, paving bricks), forming a stable three-dimensional network structure and enhancing toughness and impact resistance.
The sizing agent (coating) acts as both a “protective film” and a “bonding bridge” for glass fibers, directly affecting fiber dispersibility in cement, bonding strength with the matrix, as well as water resistance and weather resistance.
Yuni’s alkali-resistant chopped strands adopt a dual coating system of silane and starch, tailored for cement-based materials:
Silane coating: Enhances chemical bonding between fibers and cement matrices, with an interfacial shear strength of 25-35MPa. This ensures the fibers firmly lock the matrix when cracks propagate, exerting a crack-resistant effect.
Starch coating: Improves fiber dispersibility, preventing agglomeration and tangling during mixing, enabling uniform distribution in cement matrices and avoiding local insufficient or excessive reinforcement.
Some manufacturers use low-quality sizing agents, leading to fiber moisture absorption and caking, poor dispersibility after mixing, large fluctuations in cement product strength, and surface defects such as pitting and cracks. Yuni strictly controls sizing agent quality, with each batch of products undergoing dispersibility tests to ensure good compatibility with cement and aggregates during construction, minimal impact on concrete workability and smooth pumping.
When selecting alkali-resistant glass fiber chopped strands, it is essential to examine not only product parameters but also the manufacturer’s production capacity, quality control system and service capabilities to avoid purchasing inferior products or encountering after-sales issues.
Yuni specializes in glass fiber R&D and production, with a modern production base and globally advanced wire drawing, cutting and sizing equipment. It achieves in-house R&D and production for the entire process from raw material melting, wire drawing and forming, surface treatment to precise cutting. With sufficient annual production capacity, it can stably supply large-scale orders while supporting small-batch customization, flexibly meeting customers’ production capacity and specification requirements.
Yuni’s alkali-resistant chopped strands have obtained multiple authoritative certifications including ISO 9001 Quality Management System Certification, CE and SGS, and are produced in strict compliance with national standards and international specifications. Each batch of products is accompanied by a quality inspection report that clearly specifies key indicators such as fiber diameter, length deviation, alkali resistance and combustible content, enabling traceable quality and worry-free procurement for customers.
Always putting customers’ needs first, Yuni offers free sample testing services. Customers can first test samples for cement compatibility to verify dispersibility and reinforcement effect before bulk purchasing. In addition, our professional technical team can provide customized specification recommendations and technical guidance based on customers’ cement product types, production processes and performance requirements, helping customers optimize production formulations, reduce costs and enhance product competitiveness.
Over the past 24 years, Yuni has won the trust of 3,162 global customers with stable product quality and a comprehensive service system. Its products are exported to 126 countries and widely used in various cement products such as GRC components, precast wall panels, cement manhole covers, decorative moldings and insulation boards, accumulating rich industry application experience.
The core criteria for selecting alkali-resistant glass fiber chopped strands for cement products are qualified alkali resistance, precisely matched specifications, high-quality sizing agents and a reliable manufacturer. Yuni’s alkali-resistant chopped strands feature a high-zirconium formulation for superior alkali resistance, a full specification range of 7-17μm diameter and 3-24mm length for multi-scenario adaptability, a silane-starch dual coating for excellent dispersibility and bonding, 24 years of production experience, multiple authoritative certifications and customized services, fully meeting the reinforcement needs of cement product manufacturers.
For cement product manufacturers, choosing Yuni’s alkali-resistant glass fiber chopped strands means not only selecting a high-quality reinforcing material but also securing quality assurance and technical support. It fundamentally addresses the pain points of cracking and poor toughness in cement products, enabling enterprises to produce high-quality, highly durable cement products and enhance market competitiveness.
If you have any questions
Please contact us for free consultation and product quotation
You can leave your needs and contact information~and We can provide you with usage suggestions + product suitability analysis + free sample delivery!
Leave us your interest and contact information, and we’ll send you detailed information for your reference!
You can leave the specifications and contact information you need~ Our technicians will immediately organize the exclusive information for you and send it to your email!
You can leave your contact information here, and we will send you detailed specifications and application cases to make your purchase clearer~