By rosebell
In order to advancing the Metropolitan Waterworks Authority (MWA)’s Ninth Bangkok water supply improvement project in Thailand, Tunnel boring machine (TBM) designer and manufacturer Terratec has lowered its earth pressure balance TBM (EPBM) into place.
The date of bdeploying 4.8m-diameter EPBM was early October.
With aim of constructing a 9.1km water tunnel on Bangkok’s western side to enhance water supply capacity and quality, the Bangkok water supply improvement project will use three Terratec TBMs.
The project’s contract is up to a joint venture (JV) between Italian-Thai Development (ITD) and Nawarat Patanakarn (NWR), whereas ITD is due to launch two TBMs, namely S105 and S106, and NWR is going to manage the S102 TBM.
Inteding to link with Shaft 9A-5 from another contract, the S102 TBM was recently installed in Shaft 9B-1 to start digging almost 2.2km in the opposite direction.
Considering that TBMs have been designed to meet the project’s precise alignment requirements, their active-type articulation enables navigation through minimum curve radii of 90m and 80m.
According to Terratec: “These machines will be the company’s sixth, seventh, and eighth tight radius TBMs deployed in Thailand.”
Due to pass of the tunnel alignment through challenging geological conditions, including silty clayey sand and hard clay layers, the TBMs are equipped with soft ground cutterheads featuring a 70% opening ratio and copy cutters to manage these conditions.
Additionally, the machines will advance using conventionally reinforced concrete segments, with an additional steel lining to be installed after excavation.
As Bangkok’s tunneling projects have historically encountered risks of water and sand ingress, which increases the potential for tunnel collapse, the project team is said to have implemented rigorous safety protocols and adapted the TBM designs accordingly to reduce this problem.
Increasing capacity, decreasing leakage, as well as improving water quality for the city’s residents, are the goals of ninth Bangkok water supply improvement project.
October 2022 was the date of completing factory acceptance tests for the three TBMs of the project.
