Recently, China Concrete and Cement-based Products Association（CCPA） organized experts, scholars, entrepreneurs and people of insight in the industry to conduct extensive and in-depth discussions around "low-carbon concrete".

Jiang Qinqin: Chairman of Precast Concrete Component Branch of CCPA 

and President of Beijing Precast Concrete Institute Co., Ltd.

The definition of "low-carbon concrete" can be summarized as the general term of concrete materials, products or projects that meet the requirements of low-carbon emission indicators.

The narrow sense can be summarized as concrete prepared with less cement clinker to meet the specific engineering requirements, and green concrete that meets the requirements of low carbon emission limit can be produced by reasonable selection of raw materials, optimization of proportions of concrete mix and other technical means.

Broadly speaking, it should be evaluated from the annual average carbon emission limit requirements of the full-cycle service life of concrete raw material composition, mixing, transportation, pouring, molding, use and maintenance. Obviously, it is the essential for low-carbon concrete to improve the durability of concrete or other performance indexes to realize the service life of concrete structures.

The connotation of "low-carbon concrete" can be understood as the preparation of cement clinker of concrete, which strictly controls carbon emissions and meets the requirements of low-carbon limit in the process of concrete production, construction, usage and maintenance, and has the characteristics of good durability and long service life of concrete engineering. As the most widely used material in civil engineering, the annual demand for concrete is huge, and the carbon emission index of concrete is mainly reflected in the cement consumption. According to statistical data, 0.6 tons of carbon dioxide is emitted to produce 1 ton of cement clinker. At present, the annual output of cement in China is close to 2.4 billion tons, accounting for 55% of the total cement output in the world, and the annual emission of carbon dioxide is close to 1.5 billion tons. Therefore, how to reduce the concrete consumption and cement consumption in concrete is a major research topic confronting us, making the development of "low-carbon concrete" more relevant.

At present, the concrete industry is promoting green environmental protection, energy saving and emission reduction, which has achieved remarkable results. The development and application of technologies such as green building and prefabricated building have laid a good foundation for the future development of low-carbon concrete. Compared with the concepts of high-performance concrete and green concrete, the concept of "low-carbon concrete" put forward by China is still in the initial exploration stage, and it is necessary to build the technical standard system and development path of low-carbon concrete.

The application of low-carbon concrete is an objective requirement to implement the sustainable development of China's low-carbon economy and construction industry. It can be combined with the high-quality transformation and development of China's construction industry and the requirements of green construction. From the perspective of green building and energy saving and emission reduction, we need to plan the whole process of green building materials, design, production, construction and the carbon emission index of the whole cycle of building operation and maintenance as a whole, improve the quality and durability of the project, improve the service efficiency and service life of the building, and reduce the material and energy consumption in the process of construction and operation and maintenance, so as to achieve the green and low-carbon development goal of maintaining material saving, emission reduction, energy saving and consumption reduction in the development and operation of the whole society.

Based on the overall development goals and requirements of national carbon emission reduction and carbon neutrality, we strive to scientifically plan the green and low-carbon development goals of various industries, especially the construction industry, focus on the two high industries such as steel, cement and glass where carbon emissions are relatively concentrated at present, reduce the low-level redundant construction scale and low-quality and high-consumption project construction methods. Promoting the use of low-carbon concrete technology puts us on the green and low-carbon road of intensive and high-quality development.