Project information
| Project: | DTSS2 T-07 Inner Lining |
| Location: | Singapore |
| Application: | Tunnel construction |
| Component: | Sewage tunnel |
| Type: | Inner lining, 225 mm concrete with high resistance to microbacterial inducted concrete corrosion (MIC) |
| Delivery period: | 2020 -2023 |
| Requirements: | Durability 100 years |
| Concrete: | Compressive strength after 56 days >60 MPa |
| Fibre type: | DE 60/0.9 H |
| Dosage: | 32-40 kg/m³ |
| Total volume: | ca. 2,000 t |
| CO₂ savings: | 3,686 t CO₂¹ |
¹ KrampeHarex GWP 257 kg CO₂-Eq. compared to steel fibres from other manufacturers with a GWP of 800-2,100 kg CO₂-Eq.
CO₂ savings:
3,686 t
KrampeHarex GWP 257 kg CO₂-Eq. compared to steel fibers from other manufacturers with a GWP of 800-2100 kg CO₂-Eq.
This corresponds to approximately 1.023 transatlantic flights from Frankfurt to New York per passenger.
DTSS2
A century project
The city-state of Singapore covers a significant proportion of its drinking water requirements with a modern rainwater and wastewater treatment system. The national water authority PUB laid the foundations for this back in the 1990s with the huge “Deep Tunnel Sewerage System” project, or DTSS for short.
The second phase of the project (DTSS Phase II) involves the construction of around 50 kilometers of tunnels deep underground in the island state. Their task is to transport the wastewater produced in the south and west to the new Tuas Water Reclamation Plant. You can see the route of the tunnels in the diagram on the right.
“Honest communication at eye level and very good technical support! Thank you KrampeHarex for the cooperative partnership in this important project.”
Alexander Bahr
CPL Manager
Ed. Zublin AG – DTSS Phase 2 Project, Contract T-07
Using the right concrete mix design
to combat microbial induced corrosion
Concrete corrosion is a serious problem in waste water and sewage tunnels. Colonization with microorganisms can cause sulphuric acid to form in the tunnels, which can lead to biogenic sulphuric acid corrosion.
Inorganic and organic sulphur compounds in wastewater are converted by bacteria into sulphides, which then become hydrogen sulphide. The resulting sulphur oxidized on the concrete surfaces is converted to sulphuric acid by bacteria and the acid attack on the concrete begins.
The MIC concrete project was developed and tested as steel fibre reinforced concrete with high resistance to biogenic sulfuric acid corrosion in order to meet the required 100-year durability requirement.
DE 60/0,9 H
The tunnel's best buddy
The reinforcement of the inner lining is ensured with DE 60/0.9 H from KrampeHarex. This cold-drawn wire fibre has a length of 60 mm, a diameter of 0.9 mm and a tensile strength of 1,900 MPa.
It provides optimal reinforcement for the tunnel while increasing durability, service life and significantly reducing CO₂ emissions compared to conventional reinforcement with steel bars.
Would you like to find out more about this fibre?
“Thanks to the high performance of our fibres, it was possible to optimize the dosage in the concrete and dispense 100% with steel bars. A benefit for everyone involved in the project and, above all, our environment.”
Dr. Christian Neunzig
Technical Manager Construction Technology
Further references from
the sector tunnel construction
Do you have questions
about the project?
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Your direct line
to KrampeHarex
Christian Braun
Projectmanagement Tunnel construction & Mining
