Speaker
Description
Civil infrastructure assets such as underground pipes, manholes, access chambers, and pumping stations are frequently exposed to aggressive environments including sulphates, chlorides, and biogenic sulphuric acid. Traditional general-purpose (GP) and blended (GB) cements often lack the chemical resistance needed, leading to shorter service life and higher maintenance costs. This study evaluates commercially available specialty binders—calcium aluminate cements (CAC) and geopolymers—as durable, cost-effective alternatives for precast sewer infrastructure.
Assessment followed Australian standards AS 4198, AS 3600, WSAA codes WSA 160 and WSA 161, and Holcim’s casting requirements. Durability was evaluated through in-situ exposure in operational sewers with varying corrosion severity and accelerated laboratory corrosion testing. For casting suitability, high-performing binders were used in concrete mixes with natural coarse sand from Clarence Quarry and granite aggregates from Lynwood Quarry. These mixes were tested for workability, early strength development, and other key production and performance properties critical for efficient casting, demoulding, and safe handling.
Key durability factors were grouped as chemical stability (binder convertibility and phase development), microstructural characteristics (porosity and aggregate compatibility), mechanical performance (compressive strength), and acid resistance capacity.
Results demonstrate that select specialty binders meet both durability and casting requirements, supporting their use in wastewater infrastructure. While long-term field validation continues, current data provide a strong foundation for integrating high-performance, commercially available binders into Australian sewer networks.
Affiliations
The University of Sydney, Sydney, NSW, 2006, Australia
| Title | Performance Assessment of Specialty Cements for Manhole Construction in Australian Sewer Infrastructure |
|---|---|
| Keywords | manhole construction, calcium aluminate cement, geopolymer, sewer infrastructure, durability assessment |