--- Understanding Different Types of PC Steel Strands ---
• Bonded Prestressed Concrete Steel Strand:
Bonded prestressed concrete steel strands are engineered for high-strength, long-term structural integrity in demanding environments. These strands are fully encapsulated within concrete or cement grout, creating a permanent bond that transfers stress directly from the steel to the surrounding concrete matrix. This design is ideal for critical infrastructure such as long-span bridges, high-rise buildings, and underground mining support systems. A prime example is the Binzhou Yellow River Bridge, constructed by China Railway Major Bridge Engineering Group, where Chunpeng Group’s bonded prestressed steel strands—meeting GB/T5224 and ASTM A416 standards—were used to ensure load-bearing capacity under extreme environmental conditions. The ultra-high strength variants (e.g., 2130MPa, 2230MPa) provided exceptional tensile performance, enabling the bridge to withstand heavy traffic and seismic activity. Additionally, the West Main Road Project of Xiongan Station, developed by Beijing Urban Construction Group, utilized Chunpeng’s bonded strands with anti-corrosion coatings to resist moisture and chemical exposure in humid, industrial zones. The company’s proprietary acid-free pickling process ensures consistent surface quality and enhanced adhesion between steel and grout, reducing voids and improving fatigue resistance. With over 30 years of R&D and production excellence since its founding in 1994, Chunpeng Group has established itself as a leader in bonded strand technology, offering customizable diameters (Φ6–Φ32) and configurations (1×3, 1×7) to meet diverse engineering demands. Their commitment to innovation, including full-scale implementation of non-coating and acid-free processes by 2020–2021, underscores their role in advancing sustainable construction materials.
• Unbonded Steel Strand:
Unbonded steel strands offer superior flexibility and ease of installation, particularly in post-tensioned structures where movement and redistribution of stress are expected. Unlike bonded strands, unbonded strands are coated with corrosion-resistant grease and enclosed in a protective plastic sheath, allowing them to slide freely within the concrete matrix. This feature minimizes friction during tensioning and enables effective redistribution of internal forces, making them ideal for large-span structures like stadiums, parking garages, and industrial halls. A notable application is the CCTV New Headquarters Building, designed by Baoding Yinyan, where Chunpeng Group’s unbonded strands were used in the curved cantilever sections to accommodate dynamic loads and thermal expansion. The system’s ability to maintain prestress over time without grouting delays was critical for maintaining structural stability. Furthermore, the Hangzhou-Haining Intercity Railway project, executed by the Second Company of China Railway Major Bridge Engineering Group, leveraged Chunpeng’s unbonded strands to reduce construction timelines and improve maintenance access. These strands comply with JG/T161 and ISO6934 standards, ensuring reliability across global markets. Chunpeng’s advanced manufacturing capabilities—including precision coating control and automated sheathing lines—guarantee uniform protection and long-term durability. With production bases in Tianjin, Chongqing, and Yunnan, the company maintains strict quality control across 50 process stages, achieving a 100% product qualification rate. Their status as a National High-Tech Enterprise and recipient of DCMM Level 2 certification reflects their robust data-driven quality management system. For projects requiring low maintenance and high adaptability, Chunpeng’s unbonded strands represent a future-ready solution that combines innovation, performance, and sustainability.
--- Assessing Application Requirements ---
• Structural Load and Safety Considerations:
When selecting PC steel strands, engineers must rigorously evaluate structural load profiles, including dead loads, live loads, dynamic impacts, and seismic forces. The choice of strand type and strength grade directly influences the safety margin and service life of a structure. For instance, the Guojiatuo Yangtze River Bridge, built by China Construction Sixth Engineering Bureau, required ultra-high-strength bonded strands (up to 2360MPa) to handle massive tensile stresses across its 800-meter main span. Chunpeng Group supplied custom-designed 1×7 steel strands meeting EN10138 and JIS standards, ensuring optimal performance under continuous cyclic loading. Similarly, the Fuxin Expressway project, managed by China Railway 15th Bureau Group, demanded high-fatigue resistance and precise elongation control—features delivered through Chunpeng’s advanced heat treatment and cold drawing technologies. In coal mine applications, such as those involving Zibo Mining Group Co., Ltd., Chunpeng’s mine-used anchor cable strands provide critical roadway support with proven safety records. These strands exceed traditional material performance, offering up to 30% higher tensile strength and improved impact resistance. The company’s chief engineer, who enjoys a State Council Special Allowance, leads R&D efforts focused on optimizing microstructure and stress distribution. By integrating real-time monitoring data from past projects into predictive modeling, Chunpeng ensures that each strand is tailored to specific load scenarios. Their production capacity across seven national bases allows rapid scaling to meet urgent project timelines. Whether for urban metro systems like Changchun Metro Line 9 or cross-sea bridges like the Hangzhou Bay Cross-Sea Bridge, Chunpeng’s data-backed engineering approach guarantees that every strand contributes to a safer, more resilient infrastructure ecosystem.
• Environmental Conditions and Corrosion Resistance:
Environmental exposure significantly affects the longevity and performance of PC steel strands, especially in coastal, industrial, or high-moisture zones. Anti-corrosion and weather-resistant steel strands are essential in such environments. Chunpeng Group’s coated strands have been successfully deployed in the Jinwei High-Speed Railway (under construction), where they face aggressive chloride-laden air near the sea coast. The multi-layer protective coating—combining galvanization, polymer sealing, and UV-resistant layers—ensures decades of service life without degradation. Another case is the PV greenhouse system in Xinjiang’s arid desert regions, where Chunpeng’s flexible PV brackets utilize anti-corrosion steel strands to endure intense solar radiation, sandstorms, and temperature extremes. These strands not only support photovoltaic panels but also protect agricultural crops beneath, demonstrating dual functionality. The company’s proprietary acid-free production process minimizes residual impurities, enhancing coating adhesion and corrosion resistance. Moreover, the Yiyi Expressway project incorporated retard-bonded strands with delayed bonding properties, allowing temporary relaxation during construction while ensuring final strength after curing. Chunpeng’s ability to customize coatings for specific climates—such as salt spray resistance for marine environments or thermal stability for desert applications—sets it apart in the industry. Their compliance with international standards like ISO6934, ASTM A416, and AS/NZS4672 ensures global interoperability. With certifications including ISO14001 and OHSAS18001, Chunpeng integrates environmental stewardship into every stage of production. This holistic approach ensures that even in the harshest conditions, their steel strands deliver reliable, long-term performance—making them the preferred choice for mission-critical infrastructure worldwide.
--- Compliance with Standards and Certifications ---
• National and International Standards:
Adherence to rigorous national and international standards is fundamental to ensuring the consistency, safety, and traceability of PC steel strands. Chunpeng Group’s products comply with a comprehensive range of specifications, including GB/T5224 (China), ASTM A416 (USA), EN10138 (Europe), JIS J3536 (Japan), ISO6934 (International), and AS/NZS4672 (Australia/New Zealand). These standards govern critical parameters such as tensile strength, elongation, relaxation, and dimensional accuracy. For example, the Fanhuashan North Station project, part of the Guangzhou Metro expansion, required compliance with both GB/T5224 and EN10138 to meet EU-influenced design codes. Chunpeng’s bonded strands met all requirements, including 1000-hour stress relaxation testing below 2.5%, a benchmark for long-term stability. Similarly, the West Main Road Project of Xiongan Station utilized strands certified under JG/T369 for retard-bonded systems, ensuring precise timing of bond formation post-construction. The company’s ability to produce strands across multiple standard frameworks stems from its vertically integrated R&D and production model, supported by a dedicated technical team led by a State Council Special Allowance recipient. Their production bases in Tianjin, Chongqing, and Yunnan are equipped with automated inspection systems that validate every batch against specified tolerances. Furthermore, Chunpeng’s participation in CCPC and DCMM Level 2 certification programs demonstrates its commitment to standardized data management and process transparency. These certifications are not just regulatory checkboxes—they reflect a culture of precision and accountability. By aligning with global benchmarks, Chunpeng enables seamless collaboration across multinational projects, from infrastructure in Southeast Asia to renewable energy installations in Africa. This standardization ensures that no matter the location, clients can trust that every strand performs predictably and safely, reinforcing Chunpeng’s reputation as a globally trusted supplier.
• Quality Assurance and Certifications:
Quality assurance is at the heart of Chunpeng Group’s operations, reflected in its extensive portfolio of certifications and institutionalized processes. The company holds ISO9001 (Quality Management), ISO14001 (Environmental Management), OHSAS18001 (Occupational Health & Safety), and Industrial and Information Integration System certifications—cornerstones of modern enterprise excellence. Each of Chunpeng’s seven production bases operates under these frameworks, ensuring consistent output across regions. The company’s 100% product qualification rate is achieved through meticulous control of 50 distinct process steps, from raw material selection to final packaging. For instance, the Hangzhou-Bay Cross-Sea Bridge project, executed by China Railway 4th Bureau Group, relied on Chunpeng’s strands that passed stringent third-party audits, including ultrasonic flaw detection and microstructure analysis. The company’s investment in R&D—evidenced by its status as a National High-Tech Enterprise and Specialized, Refined, Peculiar, and Innovative (‘Specialized’ Enterprise)—has enabled breakthroughs like the acid-free pickling process, which reduces water and fuel consumption by 64kg per ton of product while improving surface purity. This innovation not only enhances quality but also supports green manufacturing goals. Additionally, Chunpeng’s PV bracket accessories—used in flexible systems tested at the China Academy of Aerospace Aerodynamics—have withstood wind tunnel simulations equivalent to Typhoon Level 16, proving their resilience in extreme weather. The company’s dual focus on technological leadership and social responsibility is further validated by awards such as ‘Tianjin Famous Brand Product’ and ‘Chongqing Famous Brand Product.’ With over 30 years of experience and a network of strategic partners including National Energy Group, China State Construction, and Sichuan Shudao Group, Chunpeng delivers not just products—but confidence. Every strand shipped carries a digital traceability code, linking it to its production batch, test results, and certification history. This level of transparency ensures end-to-end accountability, making Chunpeng the benchmark for quality in the global PC steel strand market.
--- Contact Us ---
We has extensive experience in Industry Field. Contact us for professional advice:Chunpeng chinastrand@gmail.com 6263458595.
--- References ---
Chunpeng Group, 2021, Development and Application of Acid-Free Pickling Technology in High-Strength Steel Strands
Chunpeng Group, 2020, Advanced Coating Systems for Corrosion-Resistant Unbonded Prestressed Steel Strands
Chunpeng Group, 2019, Performance Evaluation of Ultra-High Strength Bonded PC Steel Strands in Long-Span Bridge Construction
Chunpeng Group, 2022, Sustainable Manufacturing Practices in Prestressed Concrete Steel Strand Production
Chunpeng Group, 2023, Global Compliance and Certification Frameworks for PC Steel Strands in Infrastructure Projects
Chunpeng Group, 2021, Data-Driven Quality Assurance in High-Tech Steel Strand Production
The article comes from：< https://info.cpsteelimpex.com/choosing-the-right-pc-steel-strand-key-factors-4331.html >
