东非最长隧道顺利贯通
China Communications Construction Company (CCCC) has drilled the longest railway tunnel in East Africa, the company said Monday.
中国交通建设股份有限公司打通东非最长的铁路隧道。
The tunnel is part of phase 2A of the Standard Gauge Railway (SGR) that runs from the Kenyan Capital city of Nairobi to Naivasha town.
An Aijun, general manager of SGR project head office at the CCCC, said that during the excavation, the project team overcame the challenges of water leaks, uneven pressure, shallow-depth excavation, surrounding rocks, structural fault-line, and oil pipeline protection.
"With a total length of 4.5 km, the Ngong tunnel is currently the longest tunnel in East Africa and the dominant work in SGR Phase 2A," An said during celebrations to mark the breakthrough of the Ngong tunnel.
The Phase 2A which extends for about 120 km is set to be completed in 2019. The 4.5 km Ngong tunnel has been designed as a single-track railway tunnel with a clearance height of nine meters and a width of seven meters.
CCCC engineers used the New Austrian Tunneling Method (NATM) of drilling and blasting to build the tunnel and it is the first time that such a method has been used on such a large scale in Kenya.