Zhejiang Songyang Pumped Storage Power Station is a key project of China’s 14th Five-Year Plan, the largest single investment in Songyang’s history. Invested in and built by China Three Gorges Construction Engineering (Group) Co., Ltd., the station has a total installed capacity of 1,400 MW.

Recently, with the successful completion of concrete placement for the face slab of the lower reservoir dam, Sobute New Materials Co., Ltd., through its advanced crack-resistance technology and customized products, helped the project achieve China’s first “seamless face slab” — a remarkable result among comparable projects.

Overcoming Challenges: Protecting the Dam’s Lifeline

The lower reservoir dam is a concrete faceslab dam with a maximum height of 93.00 m and a regulating storage capacity of 8.05 million cubic meters. As the dam’s principal seepage-control element, the concrete face slab acts as “armor” over the upstream surface of the rockfill, bearing substantial water and seepage pressure directly. Its integrity is decisive for structural safety, and even minor cracks or leakage could threaten long-term operation. Controlling cracking in the face-slab concrete was therefore the project’s core challenge.

Technology-Driven: A Customized Solution Led by a Two-Academician Team

To meet the demanding requirements, Sobute drew on the strengths of its two-academician technical team and its State Key Laboratory to provide comprehensive technical support.

Sobute engineers took part throughout in the face-slab concrete mix design, provided detailed construction guidance, and monitored temperature and deformation at key placement bays in real time. Tailored to the project’s materials and climate, the company developed the HME-V concrete crack-resistant admixture, supplied together with a high-performance water-reducing admixture and an air-entraining admixture. This customized crack-resistance system minimized the risk of cracking at its source and laid a solid technical foundation for a high-quality face slab.

Outstanding Results: Birth of China’s First “Seamless Face Slab”

Concrete placement for the lower reservoir face slab began at the end of March this year and was completed in early May. More than a month after the final placement was completed, repeated rigorous inspections and high-definition drone scanning (several thousand photographs) found no cracks on the slab surface.

This result eliminated the conventional chemical grouting process, substantially reducing direct costs and shortening the schedule by several months. After nearly five months of continuous monitoring, the slab remains in a “zero-crack” condition. As Sobute’s first fully involved face-slab concrete project for a pumped storage station, Songyang marks a new step for the company in crack-resistance technology and products for this field.

From mix design to customized product development and full-process technical guidance and monitoring, Sobute has repaid its client’s trust with professionalism and diligence. The birth of China’s first “seamless face slab” is both the highest recognition of Sobute’s technical strength and product quality and a vivid expression of its corporate responsibility.

Looking ahead, Sobute will continue to uphold its innovation philosophy of “offering what others lack, and excelling where others offer,” deepen its work in core materials for water conservancy and hydropower engineering, and, with more advanced technology and better products, safeguard the construction of major national energy infrastructure and contribute to a clean, low-carbon, safe, and efficient new energy system.