The given diagram makes a comparison between the structures of a train station in Toronto in three different periods.
A glance at the design reveals that there have been substantial changes in the configurations of the platform, including the construction of additional floor and a pole. Moreover, it seems that the number of passengers has grown up gradually since the commencement of the reconstruction of the train station.
Prior to the erection, there were only two floors, specifically the transit concourse and a floor holding the track line. However, the layer of soil was eliminated to make way for the establishment of a pillar to withstand the weight of the upper surface. During the period, a crane and a scaffold were utilized to facilitate the constructing procedure.
The process completes with three distinct floors, one for the railway track, the others serve the commuters. Ultimately, it can be observed that more amenities including outlet stores are opened in the new pedestrian retail level.