PETALING JAYA - The ongoing construction for the Sungai Buloh-Kajang Line within the Klang Valley Mass Rapid Transit (MRT) network marked an important milestone today after the first of nine Tunnel Boring Machines (TBM) made the MRT project's first breakthrough at the underground KL Sentral Station worksite.
The machine involved is an Earth Pressure Balance TBM named Semantan 1, which was launched earlier at the Semantan North Portal on June 13.
The breakthrough follows an excavation of about 1.4km, boring a 6m diameter tunnel for trains that will head north towards Sungai Buloh.
The machine will now undergo maintenance works at the KL Sentral Station worksite before being relaunched for tunnelling through to the Pasar Seni worksite next year.
A total of nine TBMs will be used to bore the tunnel for the 9.5km underground alignment of the Sungai Buloh-Kajang MRT Line with seven underground stations.
They consist of four Earth Pressure Balance TBMs, which will be used for the Kenny Hills geological formation and five Variable Density TBMs for the Kuala Lumpur Limestone geological formation. The underground works contractor is MMC Gamuda KVMRT (T) Sdn Bhd.
Currently, seven TBMs are operational for the MRT Project at various stages of tunnelling. They are monitored by personnel who are stationed directly above where the TBMs excavate.
The first TBM was launched by Prime Minister Datuk Seri Najib Tun Razak at the Cochrane Launch Shaft on May 30, indicating the start of excavation works.