312 Arno C.D.Pronk and Rogier Houtman Fig.13. Fig.14. Fig.15 Production of the conical arch,by using the vacuum injection method. Both glass and carbon fibres are applied (photos:Rep-air Composites) 5 Indoor Ski Run After the case of the open-air theatre students carried out several studies,Henno Hanselaar has carried out a very interesting one that shows the possibilities of the structures.He designed an indoor ski run with blob appearances and analyzed the mechanical behavior of this structure.The design has been made with the aid of the computer program Maya 4.0.This program is designed to make virtual animations, which are used for example in video games.It is also easy to design blobarchitecture and kinetic buildings.A three-dimensional site was drawn with the help of geodetic information from the local government. Two lines were drawn on the ground of the slope that acted as the edges of the shell structure.Profile lines were drawn between the ends of these lines (they will function as rails)and on arbitrary distances between the ends of these lines.With the "Birail 3+"-function Maya generates a surface between the drawn profile lines. The surface can easily be transformed by changing the profile lines.The "Rebuild". function generates an even smoother surface.When the final shape is obtained,the drawing can be exported as an Iges file type. 5.1 Surface-Active Analysis of the Mechanical Behavior This file type can be imported in the computer program DIANA.It is the FEM package that is used to make a structural analysis of the rigidized shell.For pre and postprocessing DIANA makes use of the FEMGVX program.In the main menu of FEMGVX there are two options.The first is Femgen.This can be used for generating a 3d model and modifying the properties.The second option is Femview.With Femview the calculation results can be viewed.The building of the model has been done,as described above,in Maya. 5.2 Conclusions from the Structural Calculations After all the results of the structural analysis have been processed the next phase was the evaluation and the possible material adjustments.If it appears that certain values are not satisfying a different solution has to be found Most striking is the312 Arno C.D. Pronk and Rogier Houtman Fig. 13. Fig. 14. Fig. 15. Production of the conical arch, by using the vacuum injection method. Both glass and carbon fibres are applied (photos: Rep-air Composites) 5 Indoor Ski Run After the case of the open-air theatre students carried out several studies, Henno Hanselaar has carried out a very interesting one that shows the possibilities of the structures. He designed an indoor ski run with blob appearances and analyzed the mechanical behavior of this structure. The design has been made with the aid of the computer program Maya 4.0. This program is designed to make virtual animations, which are used for example in video games. It is also easy to design blobarchitecture and kinetic buildings. A three-dimensional site was drawn with the help of geodetic information from the local government. Two lines were drawn on the ground of the slope that acted as the edges of the shell structure. Profile lines were drawn between the ends of these lines (they will function as rails) and on arbitrary distances between the ends of these lines. With the “Birail 3+”-function Maya generates a surface between the drawn profile lines. The surface can easily be transformed by changing the profile lines. The “Rebuild”- function generates an even smoother surface. When the final shape is obtained, the drawing can be exported as an Iges file type. 5.1 Surface-Active Analysis of the Mechanical Behavior This file type can be imported in the computer program DIANA. It is the FEM package that is used to make a structural analysis of the rigidized shell. For pre and postprocessing DIANA makes use of the FEMGVX program. In the main menu of FEMGVX there are two options. The first is Femgen. This can be used for generating a 3d model and modifying the properties. The second option is Femview. With Femview the calculation results can be viewed. The building of the model has been done, as described above, in Maya. 5.2 Conclusions from the Structural Calculations After all the results of the structural analysis have been processed the next phase was the evaluation and the possible material adjustments. If it appears that certain values are not satisfying a different solution has to be found Most striking is the