Building envelope membrane as flexible formwork for concrete panels

Thesis: M. Eng., Massachusetts Institute of Technology, Department of Civil and Environmental Engineering, 2014.Cataloged from PDF version of thesis.Includes bibliographical references (pages 126-127).This thesis investigates the use of a building envelope membrane as fabric-like formwork for exterior cladding systems in buildings. The exterior wall system (i.e., fagade) has evolved to meet the demands of the built environment including protecting occupants and interior space from the environment and, at times, create the building form and provide support for the roofs, floors and ceilings. To accommodate the demanding needs of the industry, integrated exterior wall systems have emerged. This type of panel uses traditional building materials in innovative applications. However, existing products continue to encounter some similar issues associated with traditional building methods. This research aims to propose a concept for an integrated exterior wall system that uses traditional building material in a unique application. Overall, the system will function as the building envelope as well as a load transferring mechanism. The main objective is to study the feasibility and limitations of the design through two experiments. The first experiment assesses the effect of a flexible formwork on the 28-day compressive strength of concrete formed with an array of different types of membranes. The second experiment determines the possibility of implementing an air/water barrier in a physical form-finding application. The desired outcome of the work is to evaluate the practicality of the proposed design and further understand the implications and limitations associated with the system. As a result of the experiments, the application of air/water barriers as tension-like fabrics was found to be applicable. In addition, it was concluded that permeable membrane formwork has a greater impact on the surface properties than the bulk concrete; however, overall the permeable membrane formwork produced a higher strength concrete.by Chelsea Lynn Sprague.M. Eng