The structural design for the new Southern hall of Rotterdam Central Station

Abstract

In this part of the thesis, a study has been done to find a suitable alternative structural concept for the Southern Hall of the new Rotterdam CS. To be able to design a suitable structure, the factors that influence the design have been mapped. First, an introduction to the problem and the problem definition will be given in Chapter 3. Besides that, the different goals of the thesis have been composed and added. After that, the architectural design and the vision of the architect will be described to map the requirements according to aesthetics in Chapter 4. In Chapter 5, these influence factors have been summarized in a program of requirements in which the architectural, technical and functional requirements, the boundary conditions and goals are summarized for the design. This Program of Requirements has been a guideline for the structural design and will be described in Chapter 5. Taking this PoR into account, alternatives have been designed, each with advantages and disadvantages. It came out that it is difficult to create alternative systems within the boundary conditions. These alternatives have been weighed, using an MCA to map the advantages and disadvantages, to make a choice for one alternative. This analysis will be given in Chapter 6 and Appendix 11. It came out that a curved lattice structure is the most suitable structural concept to elaborate. The alternative shape, the chance of a reduction in weight and the alternative structural concept have been the most important motivation for this choice. The curved lattice structure will be elaborated and described in the second report of the thesis. This report describes the elaboration of the chosen alternative from the first report. First, the overview of the chosen design, the curved lattice shell, will be described in chapter 3. Drawings will be added to illustrate the idea behind the design. These drawings are principle-drawings of the concept and therefore not definite. The most important drawings will be added to the main report and additional information will be given in the appendices. After that, the types of lattice structures will be described in Chapter 4. It has been chosen to try to create a space frame structure. In Chapter 5, the calculations that have been made to determine the feasibility, the possibilities, the difficulties and the structural properties of a space frame structure will be described. The goal, the setup and the conclusions of each of the calculations will be treated in the report. The elaboration of the calculations are added in the Appendices. In Chapter 6, the design will be elaborated to a more detailed level. First, the most feasible grid systems that were designed will be evaluated. This research for the most suitable system is an important part of the space frame design and was done to study the most suitable structural systems and the difficulties according the execution. The conclusions according this study can be found in the report, the complete evaluation will be given in the Appendices. In this part of the survey, it was chosen to try to create a buckled space frame. After this choice, calculations have been made, which will be described in Chapter 7, to compare the buckled shape with the hypar shaped structure. It came out that the hypar shaped structure is more efficient than the buckled shape. Another important conclusion is that the overhang could not be created within the space frame system and therefore, an additional structural system has to be used to create the overhang structure. By the search for an optimal structure for the southern hall of Rotterdam Central station, it came out that it is difficult to create an effective space frame system within the given boundary conditions. Therefore, it was chosen to create structure with an alternative configuration of trusses to give a final advice according the Southern Hall. This will be described in Chapter 8. The final part of the thesis, Chapter 9 and 10, consists of the conclusions and recommendations according the structure. The first most important result of the thesis is that a system built up with trusses is the most suitable for this case. The second conclusion is that the curved shape will reduce the weight of the structure for a spaceframe. It and can be built up using straight trusses, what is a very promising idea according to structural and executional aspects. The manual and ESA-pt calculations showed that this will reduce the weight ad deflections. Besides that, the wind loads, which are governing, are also likely to decrease. Therefore, this shape deserves additional attention of the architect. The third point is that the IGWR/ARCADIS design is a very logical structure within the given boundary conditions. An alternative for the truss orientation is given in chapter 8 and can also be created. Whether it will result in a reduction of weight of the structure is unclear until accurate calculations will be made. The last conclusion is that saving can be made for the structure, when the roof thickness or the shape can be changed.