The diagrams compare the layouts of two different road tunnels between two Australian cities.
In general, the second underground path was more modern and advanced than the second one. Despite the difference in their location, their main purpose is to reduce the congestion of the main road, especially during rush hours.
Firstly, looking at the difference between the location of the two road tunnels, the first one was constructed in the offshore area, while the other was built inside the city. Moreover, two constructions were flanked by thick sand layers and stone and clay layers, respectively. Notably, the tunnel under the road is much more spacious than the first one, which is 2.5×36000 and 1.5×2200 meters, respectively in terms of height and length.
The older underground road was built for 12 years, from 1986 to 1998, with the expense of $555 million, whereas the other tunnel was constructed just in 4 years, from 2002, costing nearly double compared to the former, at 1,100 million US dollars. Requiring a higher expenditure, the newer underground road can house three cars in each lane, which is more than in the other tunnel, only two cars per entrance.
