3 December 2018
Tunnels Rt 3010 e Rt 3030
Status advancement work: 55%
On 25 November 2018, CIPA SPA broke through the last diaphragm of the Tunnel RT 3010: the first tunnel of the railway line between the cities of Relizane and Tiaret (Algeria), part of the new railway line R.T.T of 185 km in length, who must link the cities of Relizane, Tiaret and Tissemsilt to the northwest of Algeria. The railway line is intended for the transportation of passengers and goods and will support a maximum speed of 160 km/h.
The tunnel in question is one of two tunnels subcontracted to CIPA SPA by the client 'Groupe ETRHB HADDAD'. The second tunnel RT 3030, located at approximately 10 km from the RT3010, with its 690 meters of length, has been broken though by CIPA SPA on August 06, 2017.
The tunnel RT 3010 is located on the outskirts of the town of Zemmora, it has a length of 1150 meters of which the length of the natural tunnel is 1114 meters, with excavation section of 122 m3 with radius of 6,9 meters for the first 429 meters, (cruising from West to East). For the remaining part of the tunnel (685 meters), the excavation section was 80 centimeters enlarged, to provide more comfortable space to trains and convoys arriving at the Zemmora railway station. The enlarged excavation section is 130 m3 with radius of 7,3 meters.
The excavation was executed in full section, using the traditional method of excavator equipped with hydraulic hammer. The pre-coating consists of double profile IPE 180 steel arches laid down at variable pitch, electro-welded mesh and shotcrete. The final coating is in reinforced concrete with minimum thickness of 45 cm.
Most of the excavated soil is made up of hard and semi-hard rocks, sometimes fractured with marly and clayey substrates. One section of the tunnel was characterized by off-white limestone formation with marly and clayey sandy interlayers
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