Underground structure engineering load reduction backfill

With the continuous advancement of science and technology, an increasing number of underground projects are flourishing in China's engineering sector. Lightweight soil is also being increasingly applied in the field of structural load reduction, with the backfilling of subway tunnel roofs being particularly prominent.

Subway construction typically occurs in bustling urban areas, with many sections employing open-cut methods where the excavation areas are municipal roads. After the completion of the subway tunnel structure, the area needs to be backfilled to restore traffic.

Modern architecture emphasizes green environmental protection and aesthetic naturalness. Many commercial roofs in design incorporate greened roof gardens, with the conventional construction process generally using natural soil for full covering. However, ordinary soil has high water absorption rates, poor permeability, heavy self-load, and requires large equipment for construction. Under natural absorption conditions, it can reach about 2.5 tons per cubic meter, which is about five times the weight of foam concrete.

Due to the advantages such as low soil density, lightweight soil is now gradually being promoted and used in green roofs.