The scope includes the design for the following tunnels:

Quantitative Risk Analysis (QRA) Study

Performing a Quantitative Risk Analysis (QRA) for the urban road tunnel by using representative accidents covering a wide range of scenarios, a basic queue model and performing an evacuation analysis and estimating the number of casualties for each scenario for assessment of the risk level within the tunnel.

The basic framework analysis is based on the Lund QRA report, prepared by Persson (2002) and incorporating the most recent requirements of PIARC and NFPA.

The Tunnels are designed for a Heavy Good Vehicle (HGV)fire with maximum Heat Release Rate (HRR) of 150MW where the ventilation system is activated preventing fire spread to potential other HGVs behind (upstream) the initial fire.

The results of the study show that the risk-level is acceptable, when compared to Switzerland risk line criteria, then it is a good signal that the tunnel does not present a greater threat than any other risk object in the society.

General Description of the A-Ring Road Tunnel

The A-Ring Road Tunnel is part of a tunnel system under the Doha City which is going to be constructed.  Proceeding north to south, the A-Ring Tunnel passes under Al Istiqlal Street, bypasses the main road network after Al Razi Street, then is redirected under Al Diwan Street and A-Ring Road at the junction with Al Rayyan Road and terminates south and west of the A-Ring Road / Rawdat Al Khail Street Junction.

The tunnel consists of one tube with four lanes and is an unidirectional tunnel and designed for 7200 vph.