Frei Otto Munich Stadium

MUNICH OLYMPIC STADIUM//FREI OTTO//1972 gizem akgun/ nuria juanbaro sarret/kanaka raghavan _ADDA 2012-2013 GERMAN PAVILION// MONTREAL//1967//cable nets TUWAIQ PALACE//SAUDI ARABIA//1970// cable nets OLYMPIC STADIUM//MUNICH//1972// cable nets ORKS MULTIHALLE MANNHIEM //GERMANY//1975// grid shells JAPAN PAVILION EXPO 2000//HANOVER GERMANY//2000//grid shell German architect and research engineer 1957 // Development Center for Lightweight Construc on in Berlin. 1964// Ins tute for Lightweight Structures in Stu gart.

Exhibited a special gi for crea ng lightweight tent structures Computer-based procedure for determining their shape and behaviour Alterna ve system of grid shell structures HE ARCHITECT /FREI OTTO HE LIGHTWEIGHT PRINCIPLE/tensile Tensile roofs/ every part of the structure is loaded in tension with no requirement to resist compression Cable nets/ grid of structural cables in tension forming the framework supports a weather shield. An clas c Surfaces/ tension forces are in equilibrium, the centres of curvature are in opposite side of the membrane Synclas c Surfaces/ the centres of curvature are on the same side of the membrane n clas c curve hyper paraboloid hyper paraboloid/ minimum 4 pts with alteast 1 pt out of plane Less material and e? ort Remarkably large ps Combined tensile structure and biological research Only a few members,are under compression while all others, for instance, cables and membranes, are under tension For tension and rigidity, an clas c or saddle-like curvatures HE LIGHTWEIGHT PRINCIPLE UNICH OLYMPIC STADIUM /details SITE// Originally the se ng of a 1930’s air? eld,former training ground for the Bavarian Royal Army and the site of Munich’s ? rst civil airport. Ground had been used as a dump yard for ruined buildings’ rubble. 00m tall broadcast tower, s ll present today, a major landmark of the site. PROGRAM// 80,000 seats Smaller enclosed sports hall Swimming hall Warm-up arena Enclosed workout facility Housing for 3000 people UNICH OLYMPIC STADIUM /1972 Gunter Behnisch proposed light and open structures con nuous ? uid tent roo? ng resembling natural hills Frei O o’s Montreal Pavilion was the guiding piece The original system came from model studies where ladies stockings were used to simulate the tent’s surfaces al proposal CRITICAL STUDIES// Mast heights gave ghter curvature near the masts and leave the unsa sfactory ? t perimeter areas unimproved Increasing the pre-stress to ? at areas would provide the necessary stability, but only at impossibly high levels of tensioning UNICH OLYMPIC STADIUM/ini Winner of the compe on for 1972 olympic park by GUNTER BEHNISCH ERMAN PAVILLION,MONTREAL/1967 Real masterpiece of lightweight architecture,Frei O l/Behnisch Ini al mode o UNICH OLYMPIC STADIUM /comparisons UNICH OLYMPIC STADIUM /inspira Dragon? y wings are one three-thousandth of a millimeter thick Up to 1,000 sec ons Compartmental structure, wings do not tear, withstand the pressure that forms during ? ght. Driving principle for design of roof on 7 saddle-shape cable nets Square meshes that form rhomboids to assume an clas c curvature UNICH OLYMPIC STADIUM /revised roof Subdivide roof into a patchwork of separate but coupled smaller canopies Support at many points and mostly curved to suitably ght radii. Nets do not extend to the tops of medium height masts, instead hung from very tall masts Masts placed outside the roof or suspended above ground on cables keeping the areas below column-free Roo? ng for the main sports facili es

UNICH OLYMPIC STADIUM /experiments 1:125 scale models exactly proportional both in geometry and in elasticity to the envisaged full sized structures UNICH OLYMPIC STADIUM /structure Interior cables Peripheral cables Cable joints Steel masts Concrete underground founda on Acrylic panel cover UNICH OLYMPIC STADIUM /cables Interior cables//11. 7 mm mesh, 19 heavily galvanised 2. 3- and 3. 3mm steel wires A lay length of 10 x the lay diameter Main cables//? ve strands of 37 and 109 wires each Edge cables//vary in speci? a on, typical example ,lockedsurface wire rope of 81 millimetres diameter Twin cables with concentric joints assume square meshes forming rhomboids forming an clas c curves UNICH OLYMPIC STADIUM /joints Cables arranged in pairs 75×75 cm mesh,reduced number of joints Clamps+screw,one bolt per joint,easy construc on 75 cm mesh Saddle connec ons Swaged clamp connec on Erec on/The cable nets completely assembled on ground, li ed to ? nal posi ons. Prestressing/suspension cables were put in posi on, geometry and stresses cables and masts checked Connec on to anchor UNICH OLYMPIC STADIUM /masts

Tension founda ons / anchor the main cables down to earth Inclined slot founda ons (tent pegs ),gravity anchor founda ons (anchoring from self weight),earth anchor founda ons (support the masts) Temporary steel balls provided under the rubber pads to allow rota on during assembly Cylindrical masts welded steel tubes up to 80 metres long and with a 50mN (5000 ton) load capacity. Transparent roof covering/ 2. 9 x 2. 9-metre acrylic panels , 4mm thk Bolted to the intersec on nodes and angles of intersec on change every 6 degrees Temperature moulding, panels on neoprene pedestals, allowing them to ‘? at’, and sealing the joints with con nuous neoprene pro? le clamped to the panel edges Discon nuous joints allowing movement UNICH OLYMPIC STADIUM /cover UNICH OLYMPIC STADIUM /conclusions Form ? nding experiments/solu ons for large ps simultaneously gave birth to the science of compu ng . Final form depends on – shape of grid,spacing,pa ern -the geometry of the suppor ng structure – the pretension applied to the cable net and its suppor ng structure Advantages/E? cient way of using material Lightweight Large ps Quick construc on