Challenges in designing and fabrication of a thin concrete shell

Complex forms, that in history have always been challenges for architects are now becoming familiar to people working at the edge between architecture and structural design. This is, in particular, true for free form shells design. Before the digital revolution, the shell complexity was statically determined through funicular chains, and physical modelling was an essential part of the design process. Today the growth of computer modelling is accelerating the process. However, fabrication and prototyping are still essential part of the process. The growth of the additive and subtractive manufacturing industry opens new avenues for shell design as the design process can be fine-tuned through the use of Building Information Modelling (BIM), and the manufacturing process can be carried out by robotics. Thereby free flowing shell forms once too complex for traditional construction methods can now be imagined through the additive manufacturing process. This paper, presents the exploration of freeform surface through the use of Rhinoceros and its plug-ins. Three thin concrete shells, namely a continuous, a reticular and a waffle like shell are compared in terms of structural efficiency. Additive manufacturing techniques are explored for their fabrication, with a scaled ABS model produced as proof of concept. The combination of these innovative design and construction techniques aimed to produce a sustainable structure that develops strength through geometry

Sustainability of modular lightweight steel building from design to deconstruction

The increasing concerns over population growth, depletion of natural resources and global warming as well as catastrophic natural events is leading the international scientific community to envisage sustainability as a crucial goal. The built environment plays a key role on the triple bottom line of the sustainable development -- Planet, People, Profit -- because of several environmental, social and economic impacts produced by the construction sector. The acknowledged need to promote a sustainable building market is an international high-priority issue as underlined by the 2030 Agenda for Sustainable Development. Indeed one of its strategic objectives highlights to make cities and human settlement inclusive, safe, resilient and sustainable. In line with the 2020 Europe Strategy and the European 2050 Roadmap, energy efficiency and CO2 savings towards a low-carbon economy are regarded as ambitious objectives to be achieved for both new and existing buildings. Thus, controlling and reducing the environmental impacts of new constructions is fundamental. In line with this, the “Energy efficient LIghtweight Sustainable SAfe steel construction” (ELISSA) research project financed under the European FP7 aimed to develop a modular Cold-formed steel system that is energy efficient and robust. This paper presents the life cycle analysis of the building developed as case demonstrator. It analyses the environmental impacts during both the construction and the deconstruction phase. This works provides a benchmark of the current possibilities offered by lightweight steel structures in the framework of sustainable constructions

The environmental impacts of an innovative modular lightweight steel system: The Elissa case

A responsible use of resources is necessary to achieve a drastic reduction of environmental impact of the construction sector. This paper investigates the environmental impacts of a new dry construction based on the adoption of cold formed steel (CFS) members as main structural components, which was developed during the ELISSA European FP7 project. The peculiarity of the system is to achieve both high seismic and thermal performance. The first prototype, cited in this paper as ELISSA mock-up, was realized in the laboratory of University of Naples Federico II. The development of the prototype was a fundamental source for a precise evaluation of the environmental impacts. The quality of data in Life Cycle analysis (LCA) is indeed critical for the validity of any study. This paper presents the first LCA of a CFS house, which is based on a real case. The LCA is carried out according to a “Cradle to gate approach, with options EN 15804:2012 + A1: Production and Construction; End of Life”. The study demonstrates that when materials are carefully selected to reduce operational energy as well as embodied carbon, then the structural system is highly responsible for the LCA impacts. However, when one square meter of the ELISSA mock-up wall is compared to a conventional reinforced masonry wall, than the environmental impacts are much lower than those of the conventional system. This study demonstrates that the ELISSA wall with a thickness, which is one fifth of a comparable conventional system, presents Global Warming Potential that are drastically lower

Shake Table Testing for Seismic Response Evaluation of Cold-Formed Steel-Framed Nonstructural Architectural Components

The seismic response evaluation of cold-formed steel-framed nonstructural architectural components was investigated in an experimental campaign carried out within of the research study agreement between Knauf Gips KG and the Department of Structures for Engineering and Architecture of the University of Naples “Federico II”. The main objective of this research was to investigate the seismic performance of drywall nonstructural systems, i.e. cold-formed steel-framed indoor partition walls, outdoor façade walls and suspended ceilings. The present paper deals with the dynamic shake table tests. The tests were carried out on two different typologies of prototypes (Type 1 and Type 2) for a total number of five specimens. The influence on seismic response of basic and enhanced anti-seismic solutions, corresponding to the use of fixed or sliding connections at the walls and ceilings perimeter, was investigated. The seismic response evaluation of the systems under investigation has been performed according to ICBO-AC156 code with different levels of increasing intensity. Test results have been analysed in terms of dynamic identification, dynamic amplification, and fragility curves. Test results highlight that enhanced solutions have a better seismic response than basic solutions and indoor partition walls have a higher seismic “fragility” than outdoor facade walls

Seismic response evaluation of non-structural drywall building components: Planning of an experimental campaign

Russian post-revolutionary abbreviations in the first bilingual Russian dictionariesThe process of real expansion of abbreviations started at the end of 19th century and it developed tremendously in 20th century. The process of creating abbreviations in Russian became active after World War I and suddenly became widespread particularly in the post-revolutionary period. At that time abbreviations were created spontaneously and in a disorganized way, yet numerous creations were commonly used. The period of time during which they were used was usually short, compare: ОСОАВИАХИМ (= Общество содействия обороне, авиации и химическому строительству). In most cases they were names of political parties, combat, revolutionary, social and other organizations, for instance: волисполком, военкомат, ревком. This characteristic type of Russian lexis was very troublesome for Polish intellectuals who were trying to code the Polish Russian language, i.e. specific, language code with many Russian and Soviet idioms that was used by the Polish living in the Soviet Union during the post-revolutionary period. Attempts to standardize abbreviations were reflected in translation dictionaries (Polish-Russian and Russian-Polish) published in Moscow in the 30s of 20th century. Русские послереволюционные аббревиатуры в первых советских двуязычных словаряхПроцесс настоящей экспансии аббревиатур начался в конце XIX столетия и продолжался, продвигаясь большими темпами, в ХХ веке. В русском языке аббревиация сильно активизировалась после первой мировой войы, особенно бурно распространялась в ранний послереволюционный период. В то время аббревиатуры образовались спонтанно, стихийно, неупорядоченно, но – несмотря на это – многие подобные образования попадали в общенародный обиход. Как правило, их жизнь быстро обрывалась, ср. ОСОАВИАХИМ (= Общество содействия обороне, авиации и химическому строительству). В основном это были названия политических партий, боевых, революционных, общественных и др. организаций, напр.: волисполком, военкомат, ревком. Этот характерный слой русской лексики доставлял много хлопот польским интеллигентам, пытавшимся кодифицировать советский польский язык, этот особый, сильнорусифицированный и советизированный языковой код, используемый поляками, проживавшими в СССР в межвоенный период. Попытки нормализовать образования аббревиатурного типа нашли отражение в переводных словарях (польско-русском и русско-польском), выпущенных в Москве в 30-е годы ХХ в

Seismic behaviour of “all-steel” CFS structures: Experimental tests

The Cold-Formed Steel (CFS) structures are able to ensure a good structural response in seismic areas. Among them, the stick-built constructions raise a considerable interest in recent studies. In these structures, the lateral load bearing systems are CFS stud walls, that are generally realized with a frame in CFS profiles that can be braced by light gauge steel straps installed in an X configuration. In this case, the "all steel" design methodology can be adopted and the lateral resisting system is assured by the CFS strap-braced stud walls

Seismic response evaluation of non-structural drywall building components: Planning of an experimental campaign

Past earthquakes have shown that the damage to non-structural elements can severely limit the functionality of most affected buildings and cause substantial economic losses. Among the non-structural building components, the ceiling-partition systems represent a large economic investment in construction sector. Nevertheless, their seismic performance is poorly understood, because information and specific guidance are very limited. In the last years, international studies have been conducted on the seismic behaviour of light gage steel stud partition walls (Lee et al. [1], Restrepo and Bersofsky [2], Tasligedik et al. [3], Retamales et al. [4], Magliulo at al. [5]), suspended ceilings (Badillo et al. [6], Magliulo et al. [7], Gilani et al. [8], Soroushian et al. [9],) and partition walls - ceiling systems (Filiatrault et al. [10], McCormick at al. [11]). Since the behaviour of these systems cannot be easily simulated with traditional structural analysis, experimentation is the main way to assess the seismic response. For these reasons, an experimental campaign has been planned at the University of Naples Federico II with the main aim to characterize the seismic response of different Cold-Formed Steel (CFS) partition drywalls and suspended continuous plasterboard ceilings. The current paper presents the research project, in terms of experimental program, prototypes and specifically designed set-up

Seismic Design Method for CFS Diagonal Strap-Braced Stud Walls: Experimental Validation

The search for innovative methods to ensure high structural, technological and environmental performance is an important issue in the development of new constructions. Among the several available building systems, constructions involving the structural use of Cold-Formed Steel (CFS) profiles represent an efficient and reliable solution. In an effort to characterize the seismic response of CFS structures and to support the spreading of these systems, a theoretical and experimental research has been carried out at University of Naples Federico II within the Italian research project RELUIS-DPC 2010-2013. It focused on the "all steel design" solution, in which CFS diagonal strap-braced stud walls are the main lateral resisting system. In order to overcome the lack of information in the current European codes, a critical analysis of the requirements for these systems provided by the AISI S213-2007 has been carried out by comparing them with those given by Eurocodes for hot-rolled X-braced steel frames (tension-only). On the basis of the design hypothesis outlined from this analysis, a case study has been developed with the aim to define an extended experimental campaign involving 12 tests on full-scale CFS diagonal strap-braced stud walls. Finally, on the basis of experimental results, the assumed design prescriptions and requirements, such as the force modification factor and the capacity design rules, have been verified