Abstract The article deals with the hierarchical design structure, consisting of four stages of the stress state of pneumatic shells. The main tasks of designing and constructing pneumatic formworks ...during the construction of thin-walled architectural shells are considered. The introduction of pneumatic formwork into architectural and construction practice has a significant impact on the ability of the architect, builder and designer in the search for new and more advanced forms, as well as the builder in translating the creative ideas of the architect into steel and modern concrete. Thanks to the flexibility and elasticity of the material, it allows the construction of curvilinear spatial shells of a new elastic quality level. The proposed geometric model makes it possible to obtain a variety of software as well as the formation of a discrete-point frame of a finite shape by bicubic splines, which provides a predetermined accuracy for solving subsequent software design and construction problems.
Selecting the right construction formwork solution is vital to the success of a construction project. It can help speed up the construction schedule, boost quality, reduce construction costs, and ...ensure the safety of workers on the construction site. Construction contractors should carefully consider the project’s characteristics and their capacity when selecting the most suitable formwork solution. The Analytic Hierarchy Process (AHP) method is a decision-making tool that can be useful in selecting the best formwork solution for constructing high-rise buildings. The AHP method allows decision-makers to break down complex decisions into smaller, more manageable parts and to evaluate alternatives based on a set of criteria. The paper presents the process and propose the use of the method in selecting formwork options.
In this study, by applying the developed formwork automation design software to three target structures, we reviewed the applicability of the formwork automation design software for the aluminum ...formwork. To apply the formwork automation design software, we built an aluminum formwork library based on the conversion of two-dimensional (2D) computer-aided design (CAD) data to three-dimensional building information modeling data for all the components of the aluminum formwork. The results of the automated formwork layout on the target structures using the formwork automation design software confirmed that the wall and deck members were laid out by the set algorithm according to the formwork size and direction. However, because of the limited functionality of the software, the level of completion of the formwork layout was found to be lower than that of the manual formwork layout based on 2D CAD data. The currently developed software is based on a simple algorithm, but has a drawback in that the automated layout is limited to only some of its members. Therefore, additional research should be conducted on the development of advanced software through the diversification of the algorithm, automation of preprocessing of the mesh, and analysis of the relationships of all the members comprising the formwork.
The Semarang-Demak Toll Road was planned with detailed procedures to address disorganized road networks, increased traffic volumes, congestion, land subsidence, and tidal floods. It has toll ...entrances in Semarang, Genuk, and Sayung sub-districts and ends in Demak City. Its purpose is to minimize traffic jams, provide access to tourist cities, and serve as a tidal barrier sea embankment. The formwork support system's proper design is crucial to ensure the safe construction of the main structure. A unique disk lock and steel tubular scaffold are utilized for a slab-on-pile structure employing a flying falsework system. This approach results in a structurally sound and secure construction that is not susceptible to twisting, providing quick erection and disassembly, significantly improving construction efficiency. The system was employed in a portion of the Semarang-Demak toll road project, and its efficacy was evaluated using finite element analysis software. The software provides security and convenience in analyzing structures, paying attention to the nominal strength of each steel profile and the internal forces at work. All components are safe as their actual deflection falls within the maximum limit.
Платная дорога Семаранг-Демак была запланирована с подробными процедурами для устранения неорганизованной дорожной сети, увеличения объемов движения, заторов, оседания земель и приливных наводнений. Он имеет платные въезды в подрайоны Семаранг, Генук и Саюнг и заканчивается в городе Демак. Его цель — минимизировать пробки, обеспечить доступ к туристическим городам и служить морской набережной приливно-отливным барьером. Правильная конструкция системы поддержки опалубки имеет решающее значение для обеспечения безопасного строительства основной конструкции. Для конструкции плита-на-сваях с использованием системы летающих опалубок используются уникальный дисковый замок и стальные трубчатые леса. Такой подход позволяет получить структурно прочную и надежную конструкцию, не подверженную скручиванию, обеспечивающую быстрый монтаж и демонтаж, что значительно повышает эффективность строительства. Система использовалась в рамках проекта платной дороги Семаранг-Демак, и ее эффективность оценивалась с помощью программного обеспечения для анализа методом конечных элементов. Программное обеспечение обеспечивает безопасность и удобство анализа конструкций, уделяя внимание номинальной прочности каждого стального профиля и действующим внутренним силам. Все компоненты безопасны, поскольку их фактическое отклонение находится в пределах максимального предела.
Abstract
In Zeiten des Klimawandels und zunehmender Ressourcenknappheit wird die Bauindustrie mit der wachsenden Dringlichkeit konfrontiert, Ressourcenverbrauch, Emissionen und Abfälle deutlich zu ...reduzieren. Die Anwendung von Leichtbaustrategien in Verbindung mit Kreislaufproduktionsprozessen bietet einen ganzheitlichen Ansatz für dieses Problem. In dem folgenden Beitrag wird eine Methode zur abfallfreien Produktion leichter Betonbauteile mittels wiederverwertbarer Sandschalungen präsentiert. Der Einsatz von wasserlöslichen Mischungen in einem Pulverbettdruckverfahren ermöglicht die Herstellung von Schalungen für komplexe und optimierte Betonstrukturen und die Wiederverwendung des Schalungsmaterials in nachfolgenden Produktionszyklen (Bild 1). Die einzelnen Schritte des Verfahrens werden detailliert vorgestellt und am Beispiel der Herstellung eines Betonprototyps mit komplexer räumlicher Struktur illustriert.
Abstract
Recyclable Sand Formworks – Towards circular production of lightweight concrete structures
In the face of climate change and increasing resource scarcity, the construction industry is confronted with the need to significantly reduce resource consumption, emissions and waste. The application of lightweight construction strategies in combination with circular production processes offers a comprehensive approach to this problem. In the following article, a zero‐waste production process of lightweight concrete components using recyclable sand formworks is presented. The powder bed‐based 3D‐printing of water‐soluble material enables the production for geometrically complex and optimized concrete structures and the reuse of formwork material in subsequent production cycles (Fig. 1). The individual steps of the described process are presented in detail and illustrated by the example of the production of a concrete component with a complex spatial structure.
Concrete is the most widely used construction material. Worldwide consumption of cement, the strength‐giving component in concrete, is now estimated to be 4.10 Gt per year, having risen from 2.22 Gt ...just 10 years ago. This rate of consumption means that cement manufacture alone is estimated to account for 5.2 % of global carbon dioxide emissions.
Concrete offers the opportunity to create structures with almost any geometry economically. Yet its unique fluidity is seldom capitalized upon, with concrete instead being cast in rigid, flat moulds to create non‐optimized geometries that result in structures with a high material usage and large carbon footprints. This paper will explore flexible formwork construction technologies that embrace the fluidity of concrete to facilitate the practical construction of concrete structures with complex and efficient geometries.
This paper presents the current state of the art in flexible formwork technology, highlighting practical uses, research challenges and new opportunities.
Three-dimensional (3D) printing construction techniques have been increasingly developed in recent years and transferred into practical applications in some instances. However, knowledge of the ...differences between large-scale 3D printing and laboratory 3D printing is still limited. In this review, large-scale extrusion-based 3D printing concrete (3DPC) technologies are subdivided into three categories according to different printed objects and construction processes: 3D printing elements, 3D printing formworks, and monolithic 3DPC on-site. The different printability requirements of large-scale and lab-scale 3DPC are compared in this paper. Then practical problems of large-scale 3DPC are discussed, including economic and environmental optimizations, reinforcement constructions, preparation and remix of concrete, and different large-scale 3D printing systems. The construction details of reinforcements implemented with various 3D printing technologies are reviewed based on several pioneering projects. Finally, some recommendations for future work are provided for facilitating the use of large-scale 3DPC technology in practice of construction.
Robotic clay formwork three-dimensional printing combined with incremental concrete casting controls concrete's hydrostatic pressure and enables the production of building-scale structures. Clay ...formwork is self-demolding and less carbon intensive than concrete and polymer, often used in formwork additive manufacturing. This research investigates the recycling and reuse of clay to re-print formworks and tailors a self-compacting concrete formula with 60% reduced cement content and 90% larger maximum aggregate size. The study then explores integrating steel fibers and longitudinal rebars into the fabrication process to provide shear and bending reinforcement. When comparing the load-bearing behaviour of the fabricated beams against those cast traditionally using wooden formworks, the fabricated beams demonstrated 20% lower load-bearing capacity, with peak load mid-span deflections staying in a similar range. While more investigation is required to address formwork deformations using mixed steel fibers and recycled clay, this research paves the way for more sustainable concrete construction practices.
Nowadays buildings construction is performed by pouring concrete into molds called formworks that are usually prefabricated metallic modules. Defects such as stripping may possibly form during the ...removal of the formwork if the interfacial bonding between the concrete and the formwork is high. Making use of a new pull-off tensile test designed in our laboratory, a correlation has been established between the formwork surface functional signatures and its adherence propensity to concrete. The originality of this near-to-surface test was to characterize the concrete-to-formwork adherence by measuring the required force to pull the concrete from the formwork surface. The design of the test coupon was validated by finite element analysis that proves the small deformation of the tested formwork specimen under the tensile loading and the homogeneity of the applied tensile stress at the interface. The interfacial bonding to concrete has been compared between bare and coated formwork. Both metallic and polymer coatings have been studied. The analyses of the pull-off test results enabled us to understand the bonding mechanisms at the concrete-coating interfaces. The pull-off tensile test was proven capable of ranking formwork coatings according to their adherence to concrete.
•Determination of the concrete adherence stresses on formwork skins by a new designed small-scale pull-off test.•Correlation established between signatures of formwork surfaces and the concrete adherence.•Uncoated and coated formwork skins were compared.•The wettability was studied using the sessile drop method to determine the level of capillary effect of concrete.•Surface texture of materials was considered to determine the ability of concrete trapping.
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