The ISO 12856 Series Standards Are International Guidelines Related To Composite Materials

The use of composite materials in rail transportation has rapidly increased. Composites are now widely used in structural components, carriages, seats, and interior fittings, significantly reducing weight, improving fuel efficiency, and greatly lowering maintenance costs. Given the wide variation in the performance of composite materials, ensuring their safety in rail transportation is of paramount importance.

ISO 12856 series of standards

The ISO 12856 series of standards primarily addresses the application of composite materials in railway components such as railway ties, bearers, and transoms. It covers material characteristics, product testing, and general requirements.

ISO 12856-1:2022 – Railway Applications — Polymer Composite Sleepers, Bearers, and Transoms — Part 1: Material Characteristics
This standard sets detailed requirements for the material properties of composite railway ties and transoms. It specifies the material's suitability under high loads and harsh environments, demanding high durability and environmental adaptability. For instance, composite railway ties must demonstrate excellent corrosion resistance to counteract the long-term threat of soil corrosion. UV resistance is also an important factor to ensure that the materials do not age rapidly under outdoor conditions. To ensure consistent performance, this standard requires physical and chemical property testing of each batch of materials to guarantee the reliability of their properties.

ISO 12856-2:2020 – Railway Applications — Polymer Composite Sleepers, Bearers, and Transoms — Part 2: Product Testing
ISO 12856-2 focuses on testing the physical performance of products, including core aspects such as load-bearing capacity, durability, and toughness. Railway ties are subjected to long-term, heavy, and frequent loads, and therefore, this standard includes compression testing and long-term fatigue performance evaluation. These tests ensure that composite railway ties maintain structural integrity under high-load conditions, preventing deformation and damage. The testing simulates real-world loading conditions by subjecting samples to multiple cycles of loading, assessing their service life under various extreme conditions.

ISO 12856-3:2022 – Railway Applications — Polymer Composite Sleepers, Bearers, and Transoms — Part 3: General Requirements
ISO 12856-3 outlines the general requirements for composite materials used in rail transportation applications to ensure they can withstand the complex railway environment. The standard covers comprehensive performance requirements, including impact resistance, load-bearing capacity, aging resistance, and moisture resistance. It also specifies manufacturing processes and production consistency control. In terms of testing methods, ISO 12856-3 recommends using a range of testing approaches, including dynamic load tests that simulate real-world scenarios and long-term outdoor exposure tests, to comprehensively assess the material's environmental adaptability.