2 EPB Shields from Herrenknecht have provided first-class work during tunnel excavation of the large scale >>Abu Hamour Southern Outfall Project<<. After just about 5 kilometers of tunnelling each, both high-tech machines broke through the target shaft precisely to the millimeter in quick succession of each other. The segmental lining method has proven successful in the smaller diameter range for the first time in Qatar. The newly created sewage tunnels are important to better protect the city and the inhabitants of Doha from floods after heavy rainfalls.
Doha/Schwanau, September 23, 2015. Both Herrenknecht TBMs each with a diameter of 4.47 meters only required 12 and 14 months respectively for their tunnel sections. Under the professional guidance of the responsible construction company Salini-Impregilo they achieved remarkable top performances of up to 165 meters per week. At a depth of around 30 meters, the EPB method proved to be the optimum choice to master the cohesive soil with its high proportion of rock in Doha. Herrenknecht designed a special cutting wheel with a large opening ratio for the customer - resulting in correspondingly efficient material excavation. High maximum push forces ensured top advance rates for both machines. The final breakthrough on 29th of July marked the conclusion of Phase 1 of the tunnelling work on the >>Abu Hamour Southern Outfall Project<<.