Aggregate accounts for about 70% of the volume of cement concrete, which has an important influence on the performance of concrete. Aggregate can be divided into natural and artificial by source, and heavyweight aggregate, ordinary aggregate and lightweight aggregate by density.

From the perspective of industrial technology development, lightweight aggregate is not a new material, but today's lightweight aggregate materials differ from previous concepts whether from the perspective of concrete innovation or environmental protection and waste utilization. Nowadays, against the background of building a sound ecological environment guided by the philosophy of "lucid waters and lush mountains are invaluable assets", the policy of prohibiting and restricting the mining of natural high-quality ore aggregates by local governments will become a long-term national policy, realizing the large-scale utilization, large-scale production and high-value innovation of solid wastes, and providing a better opportunity for the development of waste recycling lightweight aggregate industry. Large amounts of municipal solid waste which can't be treated and recycled in other industries are exactly in line with the green development of lightweight aggregate industry. The application of lightweight aggregate in structural concrete and functional concrete provides a rare opportunity for the development of lightweight aggregate industry.

Yichang Binjiang International Commercial & Residential Building (101.1m)-the first 100m high building with high strength lightweight aggregate concrete as the main structure in China.

In addition, due to the increasing cost of natural aggregate, it provides an opportunity for the development of artificial lightweight aggregate industry which was affected by high cost in the past. The cost difference of replacing natural aggregate with lightweight aggregate of equal volume in unilateral concrete is reduced, and the comprehensive construction cost of the whole project is significantly reduced by using lightweight aggregate concrete under the same load performance. Numerous engineering practices in developed countries have proved that, due to the high strength and light weight of structural lightweight aggregate concrete, the construction of long-span bridges and high-rise and super-high-rise buildings can greatly reduce the dead weight of the structure, the foundation load and the material consumption and transportation volume, thus bringing considerable comprehensive economic benefits. At present, the demand for lightweight aggregate in engineering applications in developed countries such as the United States accounts for about 10% of aggregate demand, which is a huge potential market for China's existing aggregate market. Lightweight requirements for transportation and hoisting of prefabricated building components and lightweight requirements for concrete components in steel structures have provided huge market demand for the development and application of lightweight aggregate concrete.

The hull of Herdrun TLP floating oil platform-65700 m3 is made of high-strength lightweight aggregate concrete with the maximum density of 2000kg/m3.

The technology development of lightweight aggregate materials in China started late. Artificial lightweight aggregate was developed from 1950s, and lightweight aggregate concrete was not applied to “Luohe Bridge”in Henan Province until 1960. After more than 40 years of development, China's lightweight aggregate industry is still in a relatively backward state with extensive production technology, backward technology and weak competitiveness of product performance. It has failed to achieve energy saving, low carbon, green and environmental protection, large-scale and modern manufacturing, and there is no leading enterprise in the industry. The product performance and quality have failed to keep up with the development of ultra-high pumping concrete and high-strength and high-performance concrete, which is far from meeting the needs of downstream engineering construction.

In the face of major changes in the development of the industry, China Concrete and Cement-based Products Association(CCPA) has set up a communication platform, taking various measures to strengthen the application of lightweight aggregate and lightweight aggregate concrete in high-rise buildings, long-span projects, prefabricated buildings and so on, leading the healthy and stable development of the industry.

Gather in the Innovation and Development Forum to offer suggestions for the development of the industry

How to make the unit weight of concrete lighter and the intensity of lightweight aggregate higher, how to manufacture high-performance lightweight aggregate according to specified design performance, how to use various industrial wastes to burn high-strength lightweight aggregate, and how to design a modern green and energy-saving lightweight aggregate manufacturing factory? In the face of these problems, CCPA has established the "National Forum on Innovation and Development of Lightweight Aggregate and Lightweight Aggregate Concrete" since 2018. Experts, business representatives and technicians from the industry gathered together to talk about the future development. Up to now, the forum has been successfully held for three times, leading the development of green lightweight aggregate industry with "environmental protection, energy saving, high strength and high efficiency", supporting the development of high-performance lightweight aggregate with "green manufacturing and material design", promoting the innovative development of lightweight high-strength concrete structures with high-performance lightweight aggregate concrete, and opening up a new green, low-carbon and environmental protection development direction for industries and enterprises. Innovation Forum has become a brand forum in the industry.

The 4th National Forum on Innovation and Development of Lightweight Aggregate and Lightweight Aggregate Concrete will be held in Nanjing on March 30th, 2022 with the theme of "Green, Environmental Protection, High Performance and New Application". The 2021-2022 China Concrete and Cement Products Industry Conference and 2021-2022 China Concrete Exhibition will be held in the same place at the same time.

The 3rd National Forum on Innovation and Development of Lightweight Aggregate and Lightweight Aggregate Concrete

At present, the "3060 carbon peaking and carbon neutrality goals" is leading high-quality development, and the state vigorously promotes environmental protection and waste utilization, prefabricated buildings, green energy-saving buildings, etc., which brings new challenges and opportunities for transformation and development to enterprises in lightweight aggregate and lightweight aggregate concrete industry. The research on high performance and ultra-high performance of lightweight aggregate concrete is making important progress, and the engineering applications are increasing. The development and application of various lightweight aggregates and lightweight aggregate concrete are exploding.

Zhuhai (Guangdong Province) International Convention & Exhibition Center LC30 pumping lightweight aggregate concrete

LC40 lightweight aggregate concrete in Yichang（Hubei Province）

 Junyao Plaza Building 

Three Centers + One Alliance, leading enterprises to innovate technologies     

In order to speed up the construction of enterprise-oriented, market-oriented and Industry-University-Research-based technological innovation system, guide and support innovation elements to gather in enterprises, improve the independent innovation ability of enterprises and promote the transformation of scientific and technological achievements into real production, CCPA has carried out the construction of industrial technological innovation platforms, and built industrial key laboratories, industrial engineering technology centers and enterprise technological innovation centers in universities, research and design institutes and enterprises.

In April 2019, initiated by CCPA and built by Tianjin Cement Industry Design & Research Institute Co., Ltd. (TCDRI) the "Technology Innovation Center of Lightweight Aggregate Industry in Concrete and Cement Products Industry" was officially unveiled. The Innovation Center integrates the international first-class design capability, advanced equipment research and development capability and environmental protection strength of the cement institute, and makes every effort to build the benchmark advanced production demonstration line of lightweight aggregate in domestic lightweight aggregate industry and formulate the standards of lightweight aggregate industry. It will focus on sludge deodorization technology, sludge aging technology, lightweight aggregate granulation technology and drying technology outside kiln, advanced single-barrel rotary kiln firing system and cooling system of lightweight aggregate, the best proportioning scheme for preparing lightweight aggregate from various solid wastes, appropriate expansion temperature range and calcination system, and environmental protection treatment technology of kiln tail gas emission, so as to realize the ultra-low emission level of environmental protection; The research on the product performance of lightweight aggregate concrete will be another focus.

In April 2020, CCPA and Beijing Building Materials Academy of Scientific Research (BBMA) jointly built the "Design Innovation Center for Lightweight Aggregate Materials in Concrete and Cement Products Industry". The main function of the Innovation Center is to combine the major national strategic needs and industrial development needs in the fields of national green building, green building materials and environmental protection, with focus on solving key common technical problems in the fields of large-scale utilization of solid waste, recycling, cleaning and high added value, and realizing the key breakthrough of sustainable development in the fields of green building materials and green infrastructure by developing new green light material technologies, products and process equipment with independent intellectual property rights. 

Wharf Tower, UK (235 meters)

Water Tower，USA (260m high)

In December 2020, initiated by CCPA and built by Wuhan University of Technology (WHUT), "Collaborative Innovation Center of Green High-performance Lightweight Aggregate Concrete in Concrete and Cement Products Industry" was formally established. The Innovation Center aims at promoting the engineering application and technical progress of lightweight aggregate and lightweight aggregate concrete, and carries out the basic theory and applied technology research work of lightweight aggregate, lightweight aggregate concrete materials and lightweight aggregate components at three levels. Focusing on the research and development and application of key technologies, it will develop high-quality lightweight aggregate, high-performance lightweight aggregate concrete and special-function lightweight aggregate concrete that meet different engineering requirements, as well as related design, preparation and engineering application technology systems; It carries out industrial policy research to promote the development of China's lightweight aggregate concrete industry, and strive for national industrial technology policies and preferential tax policies by combining the function of comprehensive utilization of solid wastes in lightweight aggregate and lightweight aggregate concrete industry; It also carries out the popularization, application and standard formulation of lightweight aggregate concrete technological innovation achievements, and improve the technical level of the industry; It develops international technical exchange activities, builds a high-level academic and technical exchange platform, and provides consulting services and technical training.

Since its establishment, the three centers have carried out all kinds of work with high efficiency and high quality, and achieved certain results. At 2021-2022 China Concrete Exhibition （March 30 to April 1, 2022）, the platform co-organizers TCDRI, WHUT State Key Laboratory of Silicate Materials for Architectures, and BBMA will set up booths to display the focus, research achievements and core technologies of the innovation center.

Wuhan (Hubei Province) Securities Building applies lightweight aggregate concrete to skyscrapers

Wuhan (Hubei Province) Center Building successfully pumped

LC40 concrete to a height of 402.15m.

In recent years, CCPA has always regarded promoting the innovation and development of lightweight aggregate and lightweight aggregate concrete as a very important task. After the establishment of technology innovation center, design innovation center and collaborative innovation center, the "Green high-performance lightweight aggregate concrete collaborative innovation alliance" was established, and the first member meeting was held in WHUT in July this year. At the meeting, the member units of the alliance have initially formed a consensus on the collaborative innovation and development of lightweight aggregate and lightweight aggregate concrete. Lightweight aggregate concrete features an important development direction and field of high performance concrete. The development of lightweight aggregate materials conforms to the basic national policy of environmental protection and waste utilization, and the market demand is increasing. However, the equipment and material preparation technology level of lightweight aggregate materials industry cannot meet the needs of industry innovation. In the future, through the effective operation of the alliance, the development of China's lightweight aggregate and lightweight aggregate concrete industry will reach a new level.  

Formulate industry standards to protect the development of enterprises.

In order to promote the development of lightweight aggregate and lightweight aggregate concrete production and application, and ensure the quality of lightweight aggregate concrete, CCPA has carried out the compilation of relevant standards.

At present, there are domestic lightweight aggregate product standards such as shale ceramsite, fly ash ceramsite, sludge ceramsite, clay ceramsite, etc., but the physical, mechanical and durability requirements of lightweight aggregate are relatively low, and few performance indexes of lightweight aggregate are standardized from the perspective of safety and durability of structural lightweight aggregate concrete, which affects the application scale of lightweight aggregate in structural concrete. To this end, CCPA initiated the standard compilation of “High Strength Lightweight Aggregate for Structural Concrete”. Based on the new breakthrough of high-strength lightweight aggregate material technology and process equipment technology, lightweight aggregate products will move towards high strength and high performance, which will greatly promote the use scale of structural lightweight aggregate concrete. The association standard will contain a number of technical indicators and innovative evaluation methods, which will play an irreplaceable role in the healthy development of lightweight aggregate industry and the high-quality development of buildings.

Lightweight aggregate concrete used in island reef engineering

Lightweight aggregate concrete used in island reef engineering

In order to improve the green standard system of lightweight aggregate products in the whole life cycle from design, manufacture, use, recycling to re-creation, CCPA initiated the compilation of the association standard "Design Specification for Green Factory for Preparing Lightweight Aggregates from Solid Wastes". The standard will introduce the concept of green factory in the design stage, promote clean production from the source, reduce pollutant discharge and strengthen comprehensive utilization of resources, so that the lightweight aggregate industry can truly realize intensive land use, harmless raw materials, clean production, recycling waste and low-carbon energy, and meet the national evaluation requirements for green factories.