Construction of the Deep Tunnel Sewerage System (DTSS) Phase 2 in Singapore is still ongoing. Scheduled to be completed by 2025, the project includes 60 km of link sewers, a 30 km domestic used water tunnel and a 10 km industrial used water tunnel, located in the west of the country.
With earth retention – through metal sheet piling – being an important part of the project, a key challenge is to make sure the silent piler main body does not move while the larssen interlocking sheet pile is being slid in. This task was undertaken by the specialist silent piling technology and foundation engineering company Guan Chuan Engineering Construction, with the help of its Sennebogen 6133 E telescopic crawler crane.
Holding up the silent piler main body, the pile auger and sheet pile often exceed 20 t in weight. This is a common scenario in deep tunnel excavation work like building a sewerage system from scratch at one of the tunnelling shafts at Penjuru Road.
“Sennebogen machines are true all-rounders – even in difficult applications,“ said David Liaw, Guan Chuan’s managing director. “What has particularly convinced us for years is the robust construction, the high reliability and the easy transport. This significantly reduces operating costs.”
The decision to choose the Sennebogen 6133 E was made at bauma 2019. “The design of the machine and especially the load capacity and reach height convinced us immediately and we were sure that the 130-t crane is the ideal addition to our fleet,” said Mr Liaw.
In construction projects of this kind, stability and safety of the machine are particularly important. The Sennebogen 6133 E is equipped with a six-section, 52 m main boom, which enables the auger and sheet pile to be held steadily upright. With the optional 15 m fly jib, a reach height of almost 70 m can be achieved.
Maximum stability is ensured by the crawler undercarriage, which can be telescoped to 5.40 m track width. “Holding on to the silent piler main body while lifting and sliding in the sheet piles is often challenging. With Sennebogen’s quality boom structure, I only need to focus on sliding in the steel plate, nothing else,” said Guan Chuan’s crane operator Mohamad Hamid.
Another highlight is the Sennebogen Maxcab, which features large glass windows and can be tilted by 20°. It provides a good visibility of the working area and thus improves safety on the jobsite.
For greater efficiency, the Sennebogen 6133 E can remove and re-attach its own track undercarriage with a remote control, in addition to loading and unloading its counterweight. “There is no delay and no need for extra manpower. The Sennebogen 6133 E can retract its 5.40 m wide track to 4 m for self-loading to the low-loader,” explained Manimozhi Muthukumar, Guan Chuan’s site supervisor.
“An additional machine on the jobsite is an additional task on my list. With the Sennebogen 6133 E, there isn’t a need to have auxiliary cranes to carry out mobilisation and demobilisation,” continued Mr Muthukumar. “This makes my work a lot easier, so I can safely focus on deploying my men around the site.”
The Sennebogen 6133 E can be used for a variety of tasks. It is manoeuvrable on difficult terrain and also suitable for narrow construction sites. Depending on local conditions, the machine can move loads using the pick & carry principle.
“With our telescopic crawler cranes, we are simply more flexible. This allows us to work much more efficiently as compared to working with conventional machines,” concluded Mr Liaw.
All images: Sennebogen/Pinckers Pte Ltd