Collapse-Free Backfill Material for Pavement by Nano-Foam Technology


NAMI has developed a collapse-free backfill material which is self-leveling and soil-like, being low strength and self-compacting.

  • Collapse-Free Backfill Material for Pavement by Nano-Foam Technology 0
  • Collapse-Free Backfill Material for Pavement by Nano-Foam Technology 1
Commercialisation opportunities
Non-exclusive licensing
Problem addressed

Road and pavement damages are frequently encountered due to incomplete compaction of the underlying soil. NAMI’s backfill material provides a solution to overcome difficult underground situations, such as trenches with congested utilities, where backfilling or compaction of the conventional backfilling materials cannot be conducted satisfactorily and thus causing unsatisfactory permanent reinstatement of the pavement above.

  • Contrary to conventional soil-based backfilling which requires time consuming layer-by-layer soil compaction, NAMI's backfill material can continuously be pumped into the trench, improving productivity and pavement quality. 
  • NAMI's backfill is supplied as a ready-mix material and delivered directly to the worksite in concrete trucks, or as pre-bagged dry-mix to be mixed on-site. 
  • It can be discharged directly into the excavated area or pumped over distances to areas otherwise not accessible by ready-mix concrete truck.
Key impact
  • Highly flowable and self-compacting (slump value >200 mm)
  • High thermal conductivity (1.1 W/mK)
  • Easy excavation with manual tools (28-day compressive strength 1 MPa)
  • Ready-mix for large volume, or dry-mix for small scale backfilling
  • Silver Medal at the “2019 Geneva International Exhibition of Inventions”
  • Utility installations
  • Pavement repairs
  • Geotechnical works
  • Void filling
Nano and Advanced Materials Institute (NAMI)

As a Materials Expert, Nano and Advanced Materials Institute (NAMI) has a strong portfolio of innovative technologies to support and collaborate with the industry, offering frontier-applied research on advanced materials as well as technology transfer for commercialization success.

NAMI, incorporated in 2006, is designated by the Innovation and Technology Commission of the Hong Kong Government as a Research and Development Center for nanotechnology and advanced materials. NAMI undertakes and provides support for market-driven research in nanotechnology and advanced materials, and strives for commercialization of the technologies to benefit the industry and the society at large, as well as re-industrialization to promote the economic growth and sustainability of Hong Kong.