Keikyu 1500 Series Train at Construction Site at the East of Railroad Crossing of Keikyu Daishi Line and Sangyo-doro 2
It seems that Keikyu could not use the space along the track here. So, the company changed double track to single track, then, used the space of the removed track to build the tunnel. Since the space was very narrow, the cage-like object was built to utilize the space above the track.
Note added on 2021/01/27: Information on the web says that the cage-like object had an important role when the railroad was switched to the underground section. The eastern end of the underground section was built under the old track. To minimize the time the switching the track, the old track was moved upward and the part on the ground was connected to the new track.
Keikyu 1500 Series Train at Construction Site at the East of Railroad Crossing of Keikyu Daishi Line and Sangyo-doro 2
It seems that Keikyu could not use the space along the track here. So, the company changed double track to single track, then, used the space of the removed track to build the tunnel. Since the space was very narrow, the cage-like object was built to utilize the space above the track.
Note added on 2021/01/27: Information on the web says that the cage-like object had an important role when the railroad was switched to the underground section. The eastern end of the underground section was built under the old track. To minimize the time the switching the track, the old track was moved upward and the part on the ground was connected to the new track.