The subject of the service is concrete repair work as part of the renovation and repair of the underground car park in the 3rd construction phase of the New Town Hall on Reinhäuser Landstraße.
The building to be renovated (built between 1978 and 1980) is an underground car park, divided into 3 levels, below a 6-storey office building and an associated terrace, which will also be repaired in the course of the construction work. The underground car park was built in in-situ concrete construction except for some ceiling surfaces. The ceiling surfaces above levels -2 and -3 were largely made of semi-prefabricated elements with in-situ concrete supplementation. Two building joints divide the underground car park into three components on all 3 levels. The building joints are designed as main girders with support brackets for the ceilings. Furthermore, there are further beams in the transverse direction, which are supported on supports. In the middle of the underground car park there is a central staircase core with two elevators that leads to the upper floors, as well as stairwells in the corners of the building, which only allow access to the underground car park. The renovation measure also includes the repair of the stairwells and the sprinkler tank on level -3. The underground car park extends over a length of approx. 69.30 m and a width of approx. 42.70 m. Accessibility is at ground level. The individual levels each have an area of approx. 2300 m² and can be reached via a total of four access ramps, each with an area of approx. 110 m².
During the construction project, the ground-level underground car park level is to be provided with an approx. 300 m² noise barrier all around, which also serves as weather protection.
The construction project includes the following repair measures:
Terrace:
Collection, cleaning and storage of approx. 200 m² of natural stone slabs as well as demolition and disposal of the remaining natural stone coverings of approx. 700 m².
Demolition of a screed with a floor area of approx. 1700 m², removal of a bituminous asphalt mastic waterproofing as well as the storage plates on the rising parapet. Damaged area treatment and crack treatment, removal of existing drain bodies (21 pieces), creation of 21 DN 100 core boreholes for new drain bodies and setting of the new drain bodies.
Installation of a 1 m wide thermal insulation strip around the office building. Installation of a new waterproofing (approx. 1700 m²) on the top of the ceiling and the rising parapet surfaces.
Underground car park:
Demolition of the mastic asphalt of approx. 7400 m² on all levels, the ramps as well as the exit and entrance area and the joint profiles with a total length of 80 m.
80 m³ of ultra-high-pressure water jet work (HDW) as well as 80 m³ of concrete replacement on column and wall bases as well as the hinge brackets. Substrate preparation of the concrete surfaces by means of milling and shot blasting (6,900 m²).
Dismantling and disposal of the 600 m² thermal insulation
Damaged area treatment, approx. 150 m crack treatment and 20 m joint work. Installation of approx. 160 m of joint profiles.
Creation of a new drainage system by point drainage: core boreholes 75xDN 150 and 75xDN 200.
Installation of a sloping concrete and application of a surface protection system (OS 8 & OS 10) on the floor and base surfaces (approx. 7,500 m²). The wall and column surfaces from OK +0.50 m FFB contain an OS 2 surface protection system (approx. 2,300 m²).
reinforced concrete works of about 400 m³,
Masonry work approx. 120 m², 2,200 m reinforced concrete cutting work and 700 m³ earthworks for the ground pipe.
Installation of 4 fire doors and 40 fire doors in the area of the stairwells.
The sprinkler tank will be emptied, refurbished and laid out with a new film (160 m²) for the renovation.
The exterior façade (1,000 m²) of the underground car park is also included in the scope of the renovation and includes the treatment of damaged areas as well as the crack treatment (approx. 50 m) and, parallel to the underground car park, an OS surface protection system.