Free Roll "Romeo and Juliet"

Bobingen, Germany 1998

First Membrane of the world built with a "free roll"

Research: Prof. Alexander Furche, Prof. Dr. Robert Off (Initiators and direction)

Installation: Students of the Augsburg University

Design, planning and structural calculation: Students of the Augsburg University

Production: Students of the Augsburg University

Starting point was 10 days workshop (August 1998) at the University Augsburg. Initiated by Prof. Alexander Furche and Dr. Robert Off

15 students of the Augsburg University participated and were supported by Jürgen Hennicke (Institute for light weight structures IL, University Stuttgart)

The Idea and Basic Reflections

Task of the workshop was to create a membrane as a cover for outdoor activities at the University to be continued through light rain. Different solutions to install the membrane between the surrounding buildings were analysed.

After a lot of research, the favored solution was a freestanding membrane.

Form Finding, Calculation and Patterning
At the University Augsburg the subject of membrane structures was established and lectured by Dr. Robert Off. Students of the following semesters tried using the method of models to develop patterning and steel details.

Supporting Companies and Institutions

The whole project was done without any public finances. All involved companies, institutions and individuals donated their activities and materials to this challenging task. Without this extraordinary sponsoring the project would have been realized.

Project Realization and Construction

The survey calculations and the actual survey of the construction was done by: Prof. Dr. Weber, University Augsburg together with his students.

Planning and detailing of the steel structure and the steel-membrane connections, as well as the overall management, was done by the independent Institute of Membrane and Shell Technologies e.V. (I.M.S.)

Three reinforced concrete compression foundations were performed by the company Dywidag.

Edge cables, threads, turn buckles and bolts were chosen from the international catalogue of the Augsburger Drahtseilfabrik (AUDRA).

For the tensional forces GEWI – piles from Fa. PST Spezialtiefbau were used.

Drilling and executing the piles in the correct direction and inclination was possible due to the detailed survey of Prof. Weber.

Erection of the Mast Structures and the Membrane

At each head the plates welded to provide the connection of the membrane cables are different in location and size. Base plates are fixed to the threaded rods of the foundation. The direction and declination of the masts and guying are now already finally determined and fixed.

The steel structure had to be designed for in case that the membrane is not working for example due to severe damage. The result was the design and construction of a safety cable and a connection of all masts by a tie knot. A cable was adjusted to each mast and the tie knot. This construction we called “safety cable“.

At the head of each mast the cable is connected to the mast by a hole (drilling) and a bolt fixed to the cable is screwed into this hole by a nut. The safety cable had to be positioned above to highest level of the membrane fabric. Then it was also possible to erect the masts without the membrane.

The material chosen was a PVC – polyester Type III of the French company Serge Ferrari. Inside the “free roll“ the material had to be doubled in order to take the high forces. Confectioning was taken over by the German company CenoTec.

Opening ceremony

On the occasion of the opening ceremony, the membrane was given the name Romeo and Juliet. It is supposed to reflect form, use and usefulness. The ceremony offered all persons involved exquisite food and drink and gorgeous music. Thereby the successful completion of the project was highly appreciated by all parties.