After more than ten years of development, China's stone standards have been relatively complete in terms of product standards and test method standards. In addition, the relevant standards of the United States and Europe complement each other, and there is a lot of room for testing methods and technical indicators. The project can completely select the necessary test methods according to the design requirements, so as to obtain the required inspection reports and inspection data.
China's stone standards are mainly divided into terms and classification standards, test method standards, product standards and related standards. China's GB/T13890 "Natural Facing Stone Terminology" standard defines and explains related terms and terms in the natural stone industry. With the continuous development of the stone industry, the term standard cannot fully cover all terms and terms, so there is constant The new standard introduced complements new terms and terminology. China's stone classification standard is GB/T17670 "Natural Stone Uniform Number", which divides natural stone into granite (g), marble (m) and slate (s), and unifies the stone types that are mined in China and have a certain scale. Naming and numbering, however, the lack of necessary naming and numbering for more and more imported stone is causing confusion in the name of this part of the stone.
China's stone product standards mainly include JC/T204 "natural granite blocks", GB/T18601 "natural granite building plates", JC/T202 "natural marble blocks", JC/T79 "natural marble building plates" , gb/t18600 "natural slate", jc / t847 "shaped stone", JC830.1 "dry hanging stone", JC / T972 "natural granite tomb stone" and so on. Related stone standards include JC/T507 "Building Terrazzo", JC/T872 "Crystal Glass for Building Decoration", JC/T973 "Natural Stone Protectant for Building Decoration" and so on. China's stone test method standards are mainly GB/T966 "natural finish stone test method."
China's stone product standards have two main aspects to the specification of stone. On the one hand, it is the technical index of stone processing quality, including length, width, thickness, flatness angle, gloss and appearance quality. On the other hand, the physical chemistry of the material itself. Performance, granite, marble products include volume density, water absorption, compressive strength, bending strength, four conventional, granite increased radioactivity, slate including water absorption, compressive strength, bending strength, weathering softening depth, dry Four items of wet stability. Processing quality is an index to examine the processing technology capability of stone processing enterprises, and is also the basis for the classification of stone grades. Generally, these indicators are mainly checked in the national supervision and spot checks. This part will be checked during quality arbitration in the event of disputes in the project.
The construction industry in Beijing implements a filing system, and the filing company must also provide a sampling inspection report on the quality of processing. Daily entrusted inspection generally only requires the physical and chemical properties of the material itself, as technical documents or engineering archive technical materials during project bidding. The construction industry in Beijing generally only approves inspection reports issued by quality inspection departments at or above the provincial level. However, for the stone arriving at the construction site, it is generally required to carry out re-inspection, that is, to re-examine the performance of the actual supply of stone.
The specification of the natural stone industry has also undergone long-term development. The perfect standards constrain the development of the enterprise and provide an external environment for the benign competition and friendly development of the market.
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