Reaching for the stars with PASCHAL - the new planetarium in Halle, Germany

The official ground-breaking ceremony for the construction of the planetarium in Halle (Saale) took place on the 21st of January 2019. The city is investing 14.4 million euros with flood relief funding from the state of Saxony-Anhalt to build a replacement for the space flight planetarium on the Peissnitz Island that suffered irreparable damage in 2013. The new planetarium will be built in Holzplatz square on the Saline Island between the historical city centre (Altstadt) and the "new" town (Neustadt) inside the historically listed brick facade of a gasometer that is almost 130 years old.

The centrepiece of the planetarium, the dome-shaped room with the projection of the night sky, as well as a large foyer with an interactive exhibition space and the Star cafe will be on the ground floor of the 16 metre tall gasometer. The new first floor will provide space for teaching and administration rooms that will be able to be used by the students from the Institute of Physics on the Weinburg campus, among others. A modern, automatic telescope is located in the dome of the observatory on the roof of the gasometer which will transmit photos live from outer space into the planetarium dome or to the teaching rooms of the planetarium.

Visualisation of the finished planetarium in the old gasometer in Halle.

The industrial history will remain tangible

The special atmosphere of the old gas storage facility will however be retained in the modern concrete structure. The historically listed brick facade will therefore be repaired and refurbished. The brickwork will also remain visible on the rondel with a diameter of 34 metres. The inner facade that is also a historically listed building will be visible from the foyer and the stairs through the room-height glazing.

A new suspended slab made from in-situ concrete will be installed in the gasometer for the teaching and administration rooms.

PASCHAL formwork for a smooth construction procedure

Leinetaler Hochbau GmbH from Wallhausen, Germany received the contract for the extensive shell work. As a long-standing regular client of PASCHAL's business partner Odenwälder Baumaschinen GmbH in Merseburg, this construction company knows the quality of PASCHAL's products and decided therefore to use rental formwork from PASCHAL to construct the concrete structural components.

Approximately 350 m² of the proven Modular universal formwork were used in the foundations. In combination with the polygonal filler posts, the curved floor plans with a height of up to 3.20 m could also be polygonally formed in the system without problems.

The Modular universal formwork combined with polygonal filler posts was used as a more cost-effective, polygonal solution for the concreting of the inferior circular foundations.

The curved reinforced concrete walls in the floors were carried out using approximately 500 m² of the TTR Circular trapezoidal girder formwork, one of the best circular formworks on the market. As with all PASCHAL system formworks, TTR with adjustable radii is also impressive with its well-balanced range of panels and the ideal range of segment heights.
As a special service, PASCHAL can, upon request, also deliver pre-curved and height extended circular formwork panels to the construction site to enable you to achieve even better forming times. Thanks to the rugged height extension, even high formwork panels can also be placed by crane with no additional walers.
In this project it was also possible to form the special formwork heights of up to 7.875 m in one pour resulting in top forming times.

The flexible LOGO.3 Wall Formwork system from PASCHAL was used to produce the straight walls with heights of 2.70 m to 7.80 m. About 250 m² of this formwork was used on the construction site.
The lift core was also completed exactly as required thanks to the large range of panels in the LOGO.3 system. Use of the LOGO.3 dismantling inside corner post ensured that the dismantling process was optimised so that less time was needed for creating the internal formwork as the entire internal core can be moved without the formwork having to be disassembled.

The reinforced concrete suspended slabs were built with the PASCHAL Deck formwork system which can be adjusted flexibly to the shapes and conditions to the existing structure.

The concrete core is gradually growing in height inside the gasometer while the existing external facade is largely unchanged. TTR Circular formwork from PASCHAL is particularly suitable for the production of absolutely circular and dimensionally accurate reinforced concrete walls.

All-round care-free with PASCHAL

In addition to the products, the client was also impressed with the PASCHAL service: PASCHAL provides its clients with an all-round full service package in all phases of the project, from the creation of the formwork plans using the company's own PASCHAL-Plan pro software by application engineers as well as the organisation and material planning of the formwork and shoring systems. This enables the processes used in the formwork and support systems to be designed and optimised in the best possible way.

Precise formwork planning from PASCHAL could also be used to meet the requirements of the architect with regard to the symmetrical arrangement of the joint and tie point pattern. It was possible to obtain a perfect and reliable circular shape and dimensional accuracy thanks to the TTR Circular formwork.

Big plans for the future

It is intended that the new planetarium will open in the middle of 2021 and that it will then attract around 60,000 visitors a year.
The Holzplatz square areal will also be further developed in the coming years. More than 50 million euros will be invested in a new school with a gymnasium and outdoor facilities, a new base for the German Life Saving Association (DLRG), in the recreational and health centre in the former Technik-Karstadt and a green corridor from the river Saale to the "Park des Erinnerns" remembrance park, together with the planetarium.