Extension of the U5 in Frankfurt: dismantling of the B-level in full swing
/ Structural engineering
The expansion of the U5 underground line in Frankfurt is continuing apace. A new 2,750-metre section will connect the Europaviertel district to the existing underground network. The construction contract for the 1,160-metre tunnel section, including emergency exits and the shell of the Güterplatz station, was awarded to the U5 Europaviertel consortium in 2017. After the first layer of formwork (C layer) was dismantled in the construction pits of the future Güterplatz underground station at the beginning of the year, dismantling of the second layer of formwork, known as the B layer, has been underway since 10 June.
Two machines are currently in use to precisely cut out the massive concrete blocks in the B section. In the coming weeks, the number of wire saws used will be increased to five or six.
By mid-July, the outer walls are to be completed up to the height of the B level, i.e. just under nine metres. At the same time, the PORR civil engineering team is attaching great importance to aesthetics: thanks to high-quality materials, the concrete surfaces look almost like prefabricated elements. Another aesthetic highlight is the completed ramp collar.
The construction site is impressive with its imposing scaffolding structures. The supporting scaffolding on which the B-level to be dismantled rests will later extend to the two-metre-thick station ceiling. Steel tubes with a diameter of approximately one metre are being installed for reinforcement – only then can the B-level be completely dismantled. Sixteen steel tube stiffeners have already been installed. In the head areas (blocks 1 and 7), these are divided into three sections as there are partition walls.
In addition to the progress made, the team is particularly proud of its exemplary occupational safety record. Not a single accident has been recorded on the construction site for 300 days now. This is a strong sign of the commitment of everyone involved.