Introduction to the Basic Series of UHPC Standards by CBMF/CCPA Organization

In order to fill the gap in standards and support the growing application, scenario development and engineering practice of UHPC in China, the UHPC Branch-association of China Concrete and Cement Products Association (CCPA) has iniciated and organized the compilation of UHPC basic series of standards since 2016, consisting of 5 standards.

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Two standards for UHPC materials "Fundamental characteristics and test methods of ultra-high performance concrete" and "Premix for ultra-high performance concrete", two construction guidelines "Recommendations for production of precast ultra-high performance concrete components" and "Recommendations for on-site placing ultra-high performance concrete", and a design guideline "Specification for design of ultra-high performance concrete structures". This series of UHPC standards was jointly released by the China Building Materials Federation (CBMF) and the China Concrete and Cement Products Association (CCPA) during 2018~2022.

The Five Pillars of UHPC Standards

Fundamental Characteristics and Test Methods of UHPC (2018)

In 2018, the "Fundamental characteristics and test methods of ultra-high performance concrete" (T/CBMF 37/T/CCPA-7-2018) standard was published, which defined the material properties of UHPC, that is, "ultra-high performance concrete refers to fiber-reinforced cement-based composite materials with both ultra-high impermeability and mechanical properties". So, what performance and at what level can it be called UHPC? This is  the first and most common question for UHPC, and this standard provides a clear answer. Combined with the design, application needs and key performance characteristics of UHPC, this standard focuses on three fundamental properties of UHPC performance, i.e. impermeability (reflecting durability), compressive strength and tensile behavior (uniaxial tension responses), and specifies the grades & requirements of these three properties, as well as the corresponding test methods. Although the definition of UHPC in this standard is descriptive, the technical indicators in its content quantitatively define UHPC, that is, set the fundamental characteristics threshold of each grade of UHPC, therefore, meeting the basic properties’ requirements of the corresponding grade and verified by the tests, so as to confirm that the material formulated, produced and used has truly "ultra-high performance" in terms of mechanical properties, toughness and durability, and is a "veritable" UHPC.

Premix for Ultra-High Performance Concrete (2020)

In 2020, the "Premix for ultra-high performance concrete" (T/CBMF 96-2020/T/CCPA 20-2020) was released, which is a UHPC product standard. Commercial UHPC products are usually supplied in the form of premixes, and  this standard has detailed and standardized the classification, grades and related test methods for UHPC premix product, guiding the premix producers to carry out product quality control, test & verify the properties, as well as label partial or comprehensive necessary information of the premix products in order to speak the same language for UHPC production, design and application. This standard, together with the "Fundamental characteristics and test methods of ultra-high performance concrete", establishes a basic UHPC material standard system, and builds a "technical platform for dialogue and communications" for UHPC product R&D, production and supply, application design, component prefabrication or cast-in-place construction, etc., which can be used as the standard clause or product technical requirements agreed in the contract between the supply and demand of UHPC premix products, therefore, facilitates the production and application of UHPC products. It could be helpful for improving the performance and quality of UHPC products.

Recommendations for Production of Precast UHPC Components (2021) & Recommendations for On-Site Placing of UHPC (2021)

In 2021, the guidelines "Recommendations for production of precast ultra-high performance concrete components" (T/CBMF 127/T/CCPA 22-2021) and "Recommendations for on-site placing ultra-high performance concrete"  (T/CBMF 128/T/CCPA 23-2021) were issued to provide the guidance for each process of UHPC components precasting and on-site executing, respectively, in order to ensure the quality of UHPC prefabricated components and cast-in-place structures, as well as to improve the constructing technologies.
 

Specification for Design of UHPC Structures (2022)

In 2022, the guideline "Specification for design of ultra-high performance concrete structures" was released , which contains the basic provisions for UHPC structural design, basic component design methods, and general provisions for UHPC product application design. This standard provides guidance and technical basis for UHPC structural design and engineering application, thus is meaningful to break through the bottleneck of UHPC structural design and paved the way forward for UHPC application.