Home \ International \ Robbins Double Shield Launches in Nepal
Robbins Double Shield Launches in Nepal
05/12/2022
Pubblicato da Ettore Zanatta
• On October 14, 2022 China Overseas Engineering Group Co. Ltd and China Railway No. 2 Engineering Group Co Ltd launched a 6.4 m diameter Robbins Double Shield TBM.
China Overseas Engineering Group Co. Ltd and China Railway No. 2 Engineering Group Co Ltd launched a 6.4 m diameter Robbins Double Shield TBM. The TBM is boring the 13.1 km headrace tunnel for the Sunkoshi Marin Diversion Multipurpose Project (SMDMP) located in southern Nepal.
The tunnel is connected to a new 28.6 MW surface powerhouse on the Marin River to alleviate the shortage of power supply in the area. It will also be used for farmland irrigation in the districts of Dhanusha, Mahottari, Sarlahi, Rauthat and Bara in the Terai Plain, diverting water from the Sunkoshi River to the Marin River. Since the TBM’s launch, it has bored over 500 m, with a best week of 224.6 m, and a best day of 36.6 m.
The headrace tunnel is being bored through granitic rock with maximum overburden of 1,320 m. Geological conditions may include squeezing ground, fault zones, and water inflows. In particular, a major fault zone is located approximately 4 km into the tunnel at Dhanamana Khola. The machine was customized for the conditions, explains Mr. Liu Fengfan, Project Manager for contractor B-2/COVEC: “The TBM shield is a tapered design to reduce the risk of becoming stuck in squeezing ground; there is an enclosed cutterhead design to reduce the collapse of surrounding rock as well. The TBM has overcut capabilities, and a high thrust. It has also been designed to be equipped with an extra high torque cutterhead drive, as well as strong auxiliary thrust to be used in squeezing ground or weak fault zones to keep the machine from becoming stuck.”
As for the major fault zone, to be reached in approximately June 2023, and other zones of concern, Mr. Liu’s plan is well-thought-out: “We have prepared the advance geology forecast along with technical measures and equipment to cope with the extraordinary geological conditions. These include advance drainage holes, pre-excavation grouting (both ordinary and chemical), and other methods based on our experience. When we reach the major fault zone at Dhanamana Khola we will go slow, with more probe drilling while in the fault zone.”
The tunnel is the machine's second: on its 12.2km first tunnel (the Bheri Babai Diversion Multipurpose Project/BBDMP), the TBM finished nearly one year early and achieved 1,202 m advance in one month. “The Robbins TBM at BBDMP successfully broke through the 12.2 km tunnel and overcame extraordinary geological conditions especially in fault zones. Its stable and excellent performance and function have been verified very well. We have much confidence in the TBM to be used in SMDMP,” said Mr. Liu.
Ultime notizie di OnSite News
Components
25/04/2024
Genuine parts ensure articulated hauler quality and uptime
The importance of good quality, reliable parts when maintain...
Lifting
25/04/2024
Steil takes delivery of new Tadano AC 6.300-1 all terrain crane
Steil takes delivery of new Tadano AC 6.300-1 all terrain cr...
Earthmoving Machinery
23/04/2024
Bauma Innovation Award: Kick-off 2 May 2024
On the occasion of bauma 2025, the leading associations of t...
Lifting
19/04/2024
XCMG unveiled its premium G2 crane brand
G2 Integrates the whole process of product application, main...
Services
18/04/2024
BladeLifter from TII SCHEUERLE is the perfect choice for even the longest rotor blades
The fourth generation SCHEUERLE BladeLifter allows all fleet...
Lifting
08/04/2024
First Sinoboom AB10J boom lifts for Australia
The first of Sinoboom's AB10J articulating boom lifts to arr...
Altri International
International
25/04/2024
Genuine parts ensure articulated hauler quality and uptime
The importance of good quality, reliable parts when maintain...
International
25/04/2024
Steil takes delivery of new Tadano AC 6.300-1 all terrain crane
Steil takes delivery of new Tadano AC 6.300-1 all terrain cr...
International
24/04/2024
New Palfinger's TEC Heavy-Duty Cranes Set Standards in Power & Precision
The new Palfinger PK 1350 TEC and PK 1650 TEC heavy-duty cra...
International
24/04/2024
SSAB and Manitou Group agree on fossil-free steel
Manitou Group announces the signature of a letter of intent...
International
23/04/2024
Bauma Innovation Award: Kick-off 2 May 2024
On the occasion of bauma 2025, the leading associations of t...
International
23/04/2024
JCB expands Hydradig line-up with Plus and Pro models
JCB is meeting the needs of customers across every industry...