Heinz Isler

Wyss garden center, Zuchwil (1962)

"Kilcherschale", Recherswil (1965)

Service area, Deitingen Süd (1968)

"Sicli Pavilion", Geneva (1969)

Grötzingen Nature Theater (1977)

Tennis hall, Grenchen (1978)

Indoor swimming pool, Brugg (1981)

Aviation and Flab Museum Dübendorf (1986)

Stone church Cazis from the south (2002)

Heinz Isler (born July 26, 1926 in Zollikon ; † June 20, 2009 in Bern ) was a Swiss civil engineer . With over 1400 planned and implemented shell structures , he is considered the world's most important shell builder. Together with Robert Maillart , Othmar Ammann and Christian Menn he is counted among the most important Swiss civil engineers of the 20th century.

Life

After attending a cantonal school in Zurich , Isler began studying civil engineering at the ETH Zurich in 1945 , which he graduated with a diploma in 1950. He then worked for three years as an assistant at the ETH Zurich with Professor Pierre Lardy in setting up the model workshop for the statics chair. This was followed by nine months of studying art painting at the Zurich School of Applied Arts , before he began designing bowls as a freelance engineer in Burgdorf in 1954 .

Based on observations of nature and not with mathematical definitions, Isler developed the optimal forms of thin-walled, all-round curved shells made of reinforced concrete , which are used as roofs. For example, hanging cloths stiffened and reversed the geometry of shell roofs with free form, which, under their own weight, only show compressive forces as sectional parameters . From the inflated membrane , humpback shells were created, spanning 54 x 58 meters with 15 to 19 centimeter thick reinforced concrete shells. Using these methods, Isler designed and constructed over 1,400 shell structures. He usually demonstrated sufficient stability on models . In addition, he determined the construction process, monitored the construction and observed the load-bearing behavior of the shells for years. The shell shapes mainly show compressive stresses and thus remain practically without cracks, which is why coatings were mostly dispensed with.

Isler was part of the Behnisch & Partner team that won the 1967 competition for the Olympic site in Munich with a tent roof design . He was also involved in the implementation. He mainly worked on the massive stadium circuit.

Buildings

amongst other things

The free-form bowl of the Wyss seed and plant exhibition building in Zuchwil , Canton Solothurn , from 1962 was Isler's first larger bowl. The construction is supported on four points and spans an area of 650 square meters with floor plan dimensions of 25 × 25 meters. The 7-centimeter-thick shell has stiffening cantilever beams on each side that are 6 centimeters thick. In 2007 the concrete shell was placed under cantonal monument protection.

In 1965 the roof shell for the Kilcher company in Recherswil was made. The four-point supported shell with free edges has dimensions of 25 × 25 meters.

The two triangular shell wings above the Deitingen -Süd motorway service station on the A1 motorway were created in 1968. They were developed from the hanging principle and, with a maximum height of 11.5 meters, have dimensions of 26 × 31.60 meters each.

The roofing of the Grötzingen Nature Theater consists of a shell that is supported on five points. The shell was erected in 1977. With a thickness of 9 to 12 centimeters, it has dimensions of 28 × 42 meters and covers an area of 600 square meters.

The tennis hall in Grenchen was built in 1978 with four bowls arranged side by side, each 47 meters long and 17.3 meters wide. In 1993 the hall was expanded by two trays.

The free-form shell of the indoor swimming pool in Brugg was created in 1981 based on the hanging principle. It is supported at four corners and has dimensions of 35 × 35 meters.

The roof of the Flieger-Flab-Museum in Dübendorf consists of four juxtaposed shells, each 51.7 meters long and 18.7 meters wide.

A series of pentagonal freeform bowls for the garden center chain Les Florélites Clause ( taken over from Truffaut in 1987 ) around Paris.

The concrete shell sculpture with light slits in the stone church of Cazis was created in 1996/1997 with the help of Isler based on a design by the architect Werner Schmidt.

The hyperbolic paraboloid shell of the Heilig-Geist-Kirche in Lommiswil was created in 1967.

reception

The Langenthal Museum is dedicating an exhibition to the pioneer , which will be open to the public until June 28, 2020; Title «natural swing».

Honors

In 1983 Heinz Isler received an honorary doctorate from the ETH Zurich at the request of the Department of Civil Engineering , and in the same year he became an honorary professor at the Faculty of Architecture at the University of Karlsruhe . Isler was an honorary member of the International Association for Shell Structures (IASS), at whose founding congress in 1959 he gave his first international lecture on his shell structures. In 2006 he received the Freyssinet Medal .

literature

Ekkehard Ramm, Eberhard Schunk: Heinz Isler shells . vdf Hochschulverlag AG, Zurich 2002, ISBN 978-3-7281-2792-1 .
John Chilton: Heinz Isler in "The Engineer's Contribution to Contemporary Architecture" . T. Telford (RIBA Publications), London, 2000, ISBN 072772878-4 .
Eberhard Schunck : Heinz Isler, civil engineer and visual artist . In: Deutsche Bauzeitung , No. 4, year 2003, pp. 90–95