Tunnel 1 High Speed Railway Project Construction

High speed railway tunnel 1 is located in Jakarta City, 2.5km from the high-speed rail Halim station. This project is divided into open-cut section at the entrance and exit. Tunnel 1 enters the underground from the north side of the Jakarta - Cikampek toll road, passes through existing expressways, toll stations, interchanges, mosques, existing residential areas, and exits the ground from the south side of the expressway. It is designed as a single-tunnel double-track with a total length of 1885 m.

 

Topographic features tunnel 1 is alluvial plain area with flat terrain and open terrain. The surface layer along the tunnel covers clay, silty clay and fine gravel are the main types, with partial semi-cementation. There are mainly clay, silty clay, silt, silt, fine sand and fine conglomerate in the cave body. Seeing the topographic, geology condition, and prioritizing safety in the construction process, the construction of tunnel 1 uses Tunnel Boring Machine (TBM).

 

A tunnel boring machine (TBM), also known as a "mole", is a machine used to excavate tunnels with a circular cross section through a variety of soil and rock strata. They may also be used for microtunneling. They can be designed to bore through anything from hard rock to sand. (source: Wikipedia.com)

The construction of the Jakarta-Bandung High Speed ​​Railway project uses TBM with diameter of 13.2 m and length of 103.5 m. This is the largest TBM in Indonesia currently. This TBM consists of several parts such as cutting tools, digging tools, steering systems, grippers, drillers, controllers, soil supports, lining installers, material moving tools, and ventilation systems. TBM works with a shield tunnel method, so that the excavation process can run without disturbing activities on the surface.

In the process of operation, TBM will dismantle the soil layer as well as create a retaining pavement by installing precast concrete segments. The excavation process uses a cutter head which is located on the head of the TBM and is equipped with a drill bit. The results are then transported to the Sludge Treatment Plant.