Concrete has many advantages as a low cost and sustainable material. However, more than 5% of the planet’s total carbon emissions are associated with the production of cement, which, in fact, is predominantly due to the large volume of concrete used worldwide. It is known that traditionally designed concrete structures typically use more material than structurally required and, therefore, an important question is whether material demand can be reduced through structural optimisation. A major drawback from optimised design, however, is the cost and complexity of producing conventional rigid moulds. Fabric formwork is emerging as a new method for construction, gaining popularity among architects and engineers for the opportunity to build unique forms and to shape concrete elements efficiently. Porous fabrics, acting as controlled permeability formwork, also have proven effect on the durability characteristics of concrete. While fabric formwork has a profound potential to change the appearance of concrete structures, the shapes cast in fabrics are not defined in advance and have been often created unintentionally. The design of load-bearing reinforced concrete structures, however, requires accurate form-prediction and construction methods for securing steel reinforcement inside flexible fabrics, which presents a number of constructability challenges. For example, cover formers cannot be used to ensure adequate thickness of protective cover, inevitably affecting the acceptance of such structures in practice. This research has demonstrated that non-corrodable FRP reinforcement can be incorporated more easily than steel bars in fabric-formed concrete due to its light weight and flexibility, while it is possible to ensure ductility of such structures through confinement of concrete using FRP helices. A novel splayed anchorage system has been developed to provide end anchorage for optimised sections where standard bends or hooks cannot fit. This work also provides an experimentally verified methodology and guidance for the design and optimisation of fabric-formed elements.

Typescript (photocopy). / Digitized by Kansas Correctional Industries

No description available.

No description available.

This thesis deals with the relationship between form and strength in architecture. The proposed building is a Kindergarten which unites issues of shape, physics, and habitat. The roof is vaulted and the walls are curved for lateral resistance and in order to make folds scaled to a child. These physical moves work towards the theme of the Kindergarten: a place for the transition between home and school. / Master of Architecture

This thesis investigates minimal surfaces in design and researches their potential for constructability in concrete through the creation of physical prototypes with the design of two mold making processes, one being sacrificial and the other reusable. The study starts by acknowledging that minimal surfaces have been extensively explored in the field of differential geometry for decades. In spite of the availability of geometric definitions which provide the basic background for digital model generation (which in this text is assumed to be equal to design itself), minimal surfaces inspired very few people in their architectural design. This study attempts to look into the wider implications of minimal surfaces for architecture by taking up the challenge of designing and realizing various processes of mold making for the fabrication of such surfaces in concrete. Throughout this study, a gradient of complexity in the definition and digital modeling of minimal surfaces will be included as well as a variety of production methods in a research and fabrication based process, in order to investigate the correlation between what can be designed and what can be produced. I shall begin with a historical survey of the constructability of surfaces in thin shell concrete to provide background information for the reader. This chapter on the evolution of concrete structures presents a compilation of selected projects to illustrate the progress of thin shell construction throughout the history of architecture. It is here that I review what happened, why, and who made it possible. I draw heavily on published scholarly studies as most of the selected projects are cornerstones of the evolution of architecture and have been discussed by many others. Here, I simply attempt to remind the reader of the achievements of these projects in order to justify why investigation of the constructability of minimal surfaces may be the next step in the evolutionary process. After this section, the mathematics of surfaces in the complex plane is discussed based on information retrieved from many excellent resources. Here, the intention is to acquire information related to descriptions of various minimal surface types in differential geometry in order to be able to generate their representations in the digital environment. It would have been impossible to generate digital representations of minimal surfaces without the knowledge acquired through these descriptions. The last section provides a comparison of ruled surfaces and minimal surfaces meant to reveal the similarities and differences of such surfaces with regard to the principles of digital representation and fabrication. It provides insight into various fabrication techniques and materials to illuminate the design of a making process in which the goal is to know and control every parameter regarding both the design and fabrication of an object. The discussion of the design of a making process for a complexly shaped object provided in this part is followed by discussion of casting prototypes in concrete. In that section, the subject matter is the design and testing of various mold making techniques for the production of concrete prototypes of a selected minimal surface geometry. This section presents an increasing complexity of mold making from a sacrificial mold to a reusable mold.

Following a well-documented rise in the popularity of concrete shell application in the 20th century, thin concrete shells have experienced a global decline despite their potential as efficient structures with an economy of material use with aesthetics benefits. This phenomenon is subject to geographically determined socio-economic conditions and competition from other building solutions as a result of technological advancement in alternative construction systems. Importantly, their decline was attributed to limitations inherent to concrete shell formwork and construction methods. Being able to produce efficient shaping did not ensure that this method of construction is most cost efficient as it still remains difficult to construct double curved surfaces. The thesis addresses the limitations associated with past and present concrete shell building by proposing the use of actively-bent gridshells as re-configurable and reusable formwork for concrete shells to be designed and built. The hypothesis uses deployable scissor-jointed actively-bent gridshells as re-configurable and reusable formwork for concrete shell construction. This was developed from a series of Flash research (Benjamin, 2012) as student construction workshops to investigate the design and creation of actively-bent gridshells held between December 2008 and March 2011 in Sheffield. In this study, to understand this new system, scaled models of actively-bent gridshells were used as preliminary design aid. Deployed into three dimensional forms from a flexible flat grid mat, the structures were rigidized by bracing through triangulation restraints. The temporary rigid structure was subsequently enveloped with fabric onto which concrete was applied to create the concrete shell, thus acting as formwork. This formwork was then removed following the curing of the concrete cast to be reused repeatedly, or reconfigured into another concrete shell form. Hence, the thesis draws on the concepts, principles and ideas pertaining to three key architectural technologies: 1. concrete shell, 2. actively-bent gridshells and 3.fabric formwork. The thesis then presents a series of four prototype concrete shells constructed from different materials spanning between 1.3 meters and 2.45 meters in the workshops at the University of Edinburgh built between August 2014 and September 2015. For each experimental construction, the process of gridshell construction, fabric formwork preparation, concrete casting, gridshell formwork decentring and different design elements of openings, edges and anchorage abutments were analysed and discussed under the themes of construction, architectural tectonics and structure. The tectonic of process and material is understood and discussed based on the idea of stereogeneity (Manelius, 2012). Specifically, the relationship between gridshell as formwork and the concreting process was studied, analysed and assimilated in concrete shells built with progressive sophistication and elegance, culminating in a doubly-curved concrete shell that demonstrated both synclastic and anticlastic geometries, with further abutment simplification, edge leaning and physical openings incorporation. The study concludes with a physical concrete shell model formed by applying concrete onto fabric formwork to cover the Weald and Downland Jerwood gridshell. In the 1:20 scaled model, the proposed method is speculatively applied onto fabric stretched between pre-determined curvatures of the as-built gridshell. This formwork was subsequently removed for reuse, re-deployed and reconfigured. Using finite element analysis, the structural behaviour of the gridshell made of glass-fibre reinforced tubes and structural characteristics of the resultant concrete shell was checked. The interaction between the three technologies are discussed architectonically and structurally to inform guidelines for potential life-scale application. The thesis evidences the feasibility of the proposed system. It re-purposes a scaled model of a deployable gridshell as a physical modelling tool to facilitate concrete shell design, for both pure compression shells and "improper" shells, demonstrating its adaptability. It also promotes and reinvigorates concrete shells as possible architectural systems serving to instigate future research to revive concrete shell construction as an intelligent and intuitive way of creating structures with material economy, structural efficiency and visual elegance.

The main goal of the diploma thesis Advanced technology in construction industry is to create analysis of possibilities in the area of advanced technologies in the construction industry. Theoretical part is focused mainly on modern system formwork from composite material, on the technology of additive production and technology virtualization. In the practical part there is formwork for the family house designed. The design is made for innovative composite formwork and also for the formwork usually used in construction industry. The thesis is focused on analysis of different costs and effectiveness of used formwork.

The nature of this research is in advancing conventional structures and their methods of construction by exploring new technology. The formwork construction of the modern concrete structure involves the use of rigid materials such as steel and timber. This type of formwork often produces structures of forms with limited flexibility which would also hinder the even distribution of the induced stresses. To construct concrete structures with more organic forms; ones that responds to a more natural flow of the induced stresses, it is thought to be more logical to use flexible mould such as the fabric formwork. In such form-active shape the materials’ utilization can be maximized and the degree of material waste can be reduced. For example, when the form responds to the externally applied loads in the way that the internally incurred stresses at any point of the body closely match the capacity of the material, then the form is material-efficient and said to be in its optimal form. The use of fabric formwork, due to its permeability can also improve the quality of concrete by eliminating any air holes on the surface, and also there are reports showing the increase in concrete’s compression strength due to the reduction in water-cement ratio when cast in a fabric mould. This research concentrates on finding such material-efficient form (thus more sustainable) for reinforced concrete beam of improved material quality, through the development of the more efficient construction system of flexible fabric formwork. For this research 11 different types of beams have been built and tested in total, and their construction methods are illustrated and discussed also (Chapter 7 and Chapter 4 respectively). The designs of the beams are developed through consecutive experiment, analysis, evaluation, and modification process (Chapter 6). For the structural analysis of the beams, the most widely accepted analysis methods are reviewed and adapted (Chapter 8). Based on the evaluations of the analytical results the following variables of the beams are modified through the development of the beam designs: The effect of Compression Steel Mesh in Flange Stress Distribution Around Anchorage; Vertical and Horizontal Web Geometry Varying Depth of Flange Steel Content Also it is a part of the current research’s aim to look at the possible application of the current design methods for the design of the fabric formed beams that are discussed in this research. Thus the experimental results are compared with the results which are calculated from the standard design methods suggested by the British Standard Code of Practice (BS8110) (Chapter 9). Computational finite element (FE) analysis is carried out where more intensive analysis is required (Chapter 10). The results of the FE analysis are also compared with the theoretical and experimental results for the verification purpose. The material efficiency of the beam in its final form is assessed through the embodied energy analysis, which compares the total embodied energy consumed through the construction of the beam with a virtual beam that is designed in accordance with the BS8110 (Chapter 11). The analysis indicates that the total embodied energy of the fabric formed beam is about 20~40% less in comparison with the beam designed in accordance with the BS8110. This thesis has the purpose to illustrate and provide the practical information on the design and the construction process of the fabric formed beams, which can be used as a reference to the future research and construction.

Concrete, our most widely used construction material, is a fluid that offers the opportunity to economically create structures of almost any geometry. Yet this unique fluidity is seldom capitalised on, with concrete instead being cast into rigid prismatic moulds to create high material use structures with large carbon footprints. Our rate of concrete consumption means that cement manufacture alone is estimated to account for some 5% of global Carbon Dioxide emissions. This dissertation shows that by replacing conventional orthogonal moulds with a flexible system comprised primarily of high strength, low cost fabric sheets, the fluidity of concrete can be utilised to create structurally optimised concrete structures. Flexible formwork therefore has the potential to facilitate the change in design and construction philosophy that will be required for a move towards a less material intensive, more sustainable, construction industry. Optimisation and design processes developed in this thesis show that material savings of up to 40% are possible in flexibly formed concrete beams. Full scale structural testing of these processes is undertaken to verify the flexural and shear behaviours of non-prismatic elements. This is supported by further experimental and theoretical investigations into the durability of concrete cast in a permeable, flexible mould. Detailed analysis is provided alongside practical guidance for designers. Coupled with innovation in design and analysis techniques, flexible formwork is shown to provide a globally accessible method for the construction of low carbon, materially efficient and architecturally interesting concrete structures. Recognising the impact construction has on the environment, design philosophies centred around the need to put material where it is required are becoming increasingly desirable. This can now be achieved by replacing rigid formworks with systems comprised of flexible sheets of fabric. This is a step change in the way we think about our new concrete structures.