Recently, Guangdong Redwall New Materials Co., Ltd. received a letter of appreciation from China Construction Eighth Engineering Division Co., Ltd. for its work on the Yellow River-crossing tunnel project of “Liaocheng-Jinan Heat Transmission” project. During the construction of this major public welfare project in Jinan, Redwall’s technical expert team tackled numerous challenges and carried out systematic and meticulous testing in concrete mix design, coil-pipe testing, and on-site pouring operations. By using specially formulated functional concrete admixtures and developing multiple rigorous and efficient technical solutions, the team provided full-time, around-the-clock on-site service throughout the 19-day production and pouring period. They successfully achieved ultra-long-distance conveying of C35 self-compacting concrete through 3 km of belt transportation and 750 meters of relay pumping. This accomplishment not only ensured the smooth placement of the special concrete, but also set a new conveying record for similar projects in the industry, marking an innovative breakthrough in China’s concrete engineering sector.

It is reported that the “Liaocheng-Jinan Heat Transmission” project undertaken by China Construction Eighth Engineering Division is an ultra-long-distance heating supply project in China. It introduces waste heat from the Haoji Power Plant in Liaocheng into Jinan to help alleviate insufficient heating capacity in the urban area. The total project route is approximately 40.8 km long, while the Yellow River-crossing tunnel extends 4.5 km with a maximum burial depth of nearly 60 m, making it the key controlling component of the entire heating project. Faced with the complex underground hydrological and geological conditions beneath the Yellow River, along with the need to transport concrete over an ultra-long underground distance, timely pouring of the concrete pedestal for the heating pipeline became an exceptionally difficult challenge. On the one hand, the construction schedule was extremely demanding. On the other hand, the question of how to complete pouring smoothly over a super-long distance posed a major risk, since any pump blockage would have caused very serious consequences.

Based on the project characteristics, the China Construction Eighth Engineering Division project team adopted a plan under which the existing 3-kilometer conveyor belt of the shield tunneling machine on the east bank would first be used to transport C35 self-compacting concrete, followed by 750 meters of relay pumping to complete the placement. The 3-kilometer belt included 2,000 rollers. After passing through such intense vibration from 2,000 rollers, ordinary concrete would experience severe aggregate settlement and even segregation, making subsequent long-distance pumping impossible. On-site practice further proved that the originally proposed concrete solution could not meet the required vibration-resistance performance.

The technical team from Guangdong Redwall New Materials Co., Ltd. was invited in September 2025 to provide on-site support and identify the optimal technical approach. After extensive discussion and research, the team innovatively used a high-frequency vibration platform with specific parameters to simulate the vibration environment and pattern of the tunnel conveyor belt. In response to the technical characteristics of limestone manufactured sand, they adjusted the concrete mix design parameters accordingly. They also used a composite of multiple functional polycarboxylate products developed from proprietary monomers, supplemented with special surfactants and water-soluble polymer materials. Through a series of tests, they precisely optimized the formulation of the functional high-performance polycarboxylate products and ultimately determined an integrated self-compacting concrete solution that fully met the project requirements. Based on the research results, vibration-resistance verification on the conveyor belt and a 750-meter coil-pipe test were then carried out, and the outcomes exceeded expectations.

Starting on October 27 and lasting 19 days, the technical team of Guangdong Redwall New Materials Co., Ltd. provided 24-hour full-process support and service, ensuring the successful placement of nearly 16,000 m³ of self-compacting concrete. According to publicly available information, the ultra-long-distance conveying of C35 self-compacting concrete over 3.75 km set a new record for the longest continuous concrete conveying distance and also drove further challenge and upgrading of related technologies. From the initial testing to pumping construction and final completion of the pour, Redwall’s professional product technology, efficient after-sales service, and meticulous dedication won great admiration from the project team of China Construction Eighth Engineering Division, which highly praised the company and specially sent a letter of appreciation.

From technological innovation beneath the Yellow River to the strategic layout of its Linzhi base in Tibet, enabling nearby services for major engineering projects in Tibet, Guangdong Redwall New Materials Co., Ltd. has continued to move forward through its service to thousands of engineering projects across China. The company has accumulated profound product and technical expertise in infrastructure, water conservancy, and hydropower projects. Its strength lies in the combination of nearby production bases, product technology, and scenario-based experience, which provides the confidence and capability needed to serve super projects and push the limits of engineering achievement.