Can Tube Tunnel Crossings Relieve Urban Congestion Problems? Izmir Tube Tunnel Project Proposal Under Scrutiny

Abstract

Building underwater tube tunnel crossings to ease the urban congestion problems has become a popular approach for many cities across the globe. London, New York, Istanbul, Hamburg, Sydney and Brisbane are among these cities. However, the effectiveness and externalities of these expensive mega urban infrastructures have also been questioned widely among urban, transport and environmental planning scholars. Given the international popularity of the topic, this study places a new tube tunnel crossings project from Izmir, Turkey under the microscope. In this heuristic simulation study, policy-on scenarios were tested to determine possible impacts of the underwater tube tunnel-crossing project. The traffic impacts are discussed using simulations assigning the initial origin–destination data. The results of the study revealed that, given the two locations, outer and inner locations over the dagger-shape bay, the capacity increments on the bridge links and the links around the periphery highway did not bring any effective solutions beyond some minor improvements. The findings disclosed that the ineffectiveness of the tube tunnel crossing might be due to the excessive congestion happening all over the downtown area, which clogs the passageways to the bridge. The paper highlights the limitations of the tube tunnel-crossing project, emphasises the need for comprehensive investigations before committing to the project and advocates the emphasis to be actually given for sustainable mobility.

Environmental Fate and Effects of Foaming Agents Containing Sodium Lauryl Ether Sulphate in Soil Debris from Mechanized Tunneling

“…For this reason, the past decade has seen a wide development of roads and railways for improving it. Tunnel construction (i.e., for underground or subsoil roads) can play an important role in minimizing surface impacts, in reducing urban congestion and in avoiding deforestation in the rural areas [1][2][3] and, in some cases, tunnels are necessary for completing railing and road webs when a mountain area is present. However, tunneling excavation projects require the assessment of their sustainability before, during and after their implementation.…”

Study on Temporal and Spatial Variation in Soil Temperature in Artificial Ground Freezing of Subway Cross Passage

“…In Figure 7, lines 1 , 2 , and 3 represent the one-dimensional temperature field distribution curves of the soil at different times during the freezing period, developing in the order of 1 → 2 → 3 . The frozen zone, the frozen fringe, and the unfrozen zone are the divisions of the soil at the time represented by line 1 .…”

“…In Figure 9, lines 1 , 2 , and 3 represent the one-dimensional temperature field distribution curves of the soil at different times during the thawing period, developing in the order of 1 → 2 → 3 . The frozen zone, the frozen fringe, and the unfrozen zone are the divisions of the soil at the time represented by line 1 . The interval variation in the soil at the temperature probe during the thawing period can be divided into the following three stages: soil located in the frozen zone (line 3 ), soil located in the frozen fringe (line 2 ), and soil located in the unfrozen zone (line 1 ).…”

“…To alleviate this phenomenon, the development and utilization of urban underground space are becoming more and more important. Subways, as an underground transportation mode, occupy an important position in the process of underground space development and utilization [1]. In subway tunnel construction, cross passages with fire prevention, drainage, and connection functions should be set up at specific intervals [2,3].…”