GB8076-2008

Concrete admixtures

混凝土外加剂

GB 8076-2008 é uma norma nacional chinesa obrigatória vigente: Concrete admixtures. Setor: Eletrônicos. Foco: Segurança de produtos. Entrada em vigor: 30 de dez. de 2009.

A aplicabilidade depende do escopo do produto, da via de certificação, dos avisos da autoridade competente e das regras de transição. Solicite uma tradução ou verifique a fonte antes de usar este registro em uma decisão de conformidade.

Visão geral de conformidade

Esta visão geral está disponível por enquanto apenas em inglês.

Escopo e aplicabilidade

This standard applies to eight categories of concrete admixtures used in cement concrete, including high-performance water reducers (early-strength, standard, retarding), high-efficiency water reducers, normal water reducers, air-entraining water reducers, pumping agents, early-strength agents, retarders, and air-entraining agents. It is mandatory for manufacturers producing these admixtures for the Chinese construction market. It does not cover specialty admixtures outside these eight categories or non-cementitious binder systems.

Requisitos técnicos

The standard specifies performance indicators for concrete containing admixtures compared to reference concrete. Mandatory requirements include compressive strength ratio, shrinkage ratio, and relative durability. Other recommended indicators cover water-reducing rate, bleeding rate ratio, air content, and setting time differences. It also defines homogeneity indicators for the admixtures themselves, such as chloride ion content, total alkali content, solid content, moisture content, and density, which must not exceed the manufacturer's declared control values. Manufacturers must ensure their products meet both the mandatory concrete performance ratios and the homogeneity limits. The standard references GB/T 8077 for homogeneity testing and introduces an ion chromatography method (Appendix B) for precise chloride ion determination.

Métodos de ensaio

Testing involves preparing reference and test concrete under controlled conditions using specified materials like reference cement (per Appendix A), standard sand, and gravel. Key tests include measuring slump and slump loss over 1 hour, water-reducing rate, bleeding rate ratio, air content, and setting time differences using penetration resistance. Hardened concrete tests evaluate compressive strength ratio at various ages (1d, 3d, 7d, 28d), shrinkage ratio at 28 days, and relative durability through rapid freeze-thaw cycling. Homogeneity tests determine chemical and physical properties like chloride content and pH.

Perguntas frequentes

What products are regulated under GB 8076-2008?

It regulates eight types of concrete admixtures: high-performance water reducers, high-efficiency water reducers, normal water reducers, air-entraining water reducers, pumping agents, early-strength agents, retarders, and air-entraining agents.

Are there any updates from the previous version of GB 8076?

Yes, GB 8076-2008 replaced the 1997 version by adding high-performance water reducers and pumping agents, introducing product codes, classifying water reducers into early-strength, standard, and retarding types, and updating technical indicators by referencing EN 934-2 and JIS A 6204.

Which technical requirements are mandatory in GB 8076-2008?

The mandatory requirements in Table 1 are the compressive strength ratio, shrinkage ratio, and relative durability. All other performance indicators are recommended.

The summary above provides a high-level overview of GB 8076-2008. To ensure complete compliance for your products entering the Chinese market, a precise and professional translation of the full technical specifications is essential. Purchase our high-quality English translation of GB 8076-2008 today to access all detailed parameters, tables, and testing procedures.

Indicações de aplicabilidade

Tipo: Produto
CCS: Q12
ICS: 91.100.30
Órgão competente: Ministry of Industry and Information Technology
Comitê técnico: Ministry of Industry and Information Technology

Relações

Substitui:GB 8076-1997