Academic literature on the topic 'Formwork skin'

Flexible formworks are dominantly used for concrete constructions. These constructions become rigid after curing and their form cannot be changed, also their color or translucency is stable during usage period; i.e. these constructions are not flexible. On the other hand, in order to satisfy new architectural requirements the necessity of flexibility and smartness is undeniable for the construction.The questions of this paper are: How smartness can be added to rigid structures? What are the roles of nano-flexible formworks to turn non-flexible structures into flexible ones? To answer the research questions, descriptive - analytical research method has been adopted and empirical data gathered to feed inference mechanism. Our investigation shows that if the flexible formwork has been made by smart materials which are changeable in nano-scale, and the formwork is left on the structure even after curing, it would act as a nano-flexible skin for the structure and would satisfy some architectural requirements in nano-scale.

In recent years, a large number of studies have been carried out to investigate the behaviours of concrete filled double skin steel tube (CFDST) members due to its increasing popularity in the construction industry. This project aims to study on ultra-high performance concrete filled double-skin tubes subjected to blast loading with cross section being square for both inner and outer steel tubes using ANSYS software. It is evident that the proposed CFDST column was able to withstand a large blast load without failure so that it has the potential to be used in high-value buildings as well as critical infrastructures. The steel tubes and concrete work together well and integrity of steel concrete interface is maintained. Steel tubes in inner and outer can acts as permanent formwork and primary reinforcement. ANSYS results shows that the CFDA column can withstand applied blast load.

This paper focuses on the elastic properties and the failure behavior of tiled laminate composites. Such laminates, in which the plies are not parallel to the outer surfaces are found in InfraCore® based GFRP panels. This technology is developed for the construction of a robust FRP panel that is applicable for highly loaded structures, e.g. for bridges or lock gates. In general, the drawback in traditional FRP sandwich structures has always been debonding of skin and core. Such a debonding problem may occur after impact, followed by fatigue loading. Through the use of the InfraCore® technology, debonding is no longer possible, as multiple overlapping Z-shaped and two-flanged web structures are alternated with polyurethane foam cores acting as non-structural permanent formwork. Consequently, the fibers in the upper and lower skins as well as in the vertical webs run in all directions, especially in the connection between them, rendering a resin-dominated crack propagation impossible. As a result of the integration of core and skin reinforcement, a skin material is created in which the reinforcement is not parallel to the outer surfaces, but at a small angle. Such stacking is called a tiled laminate (TL), as opposed to plane-parallel (PP) and is not fully described by the classic laminate theory. In the paper, finite element analysis is used to assess the effect of the ply angle and the interlaminar properties on the assessment of stiffness and failure behavior of a tiled laminate.

Double skin composite (DSC) construction or Steel/concrete/steel sandwich construction (SCSS) is an innovative and relatively new form of composite construction that can be used in submerged tube tunnels, bridges deck, nuclear structures, liquid and gas containment structures, offshore and onshore structures, military shelters, and shear walls in buildings. The system consists of a plain concrete core sandwiched between two steel plates interconnected together by various types of mechanical shear connectors. The DSC construction perceives advantages that the external steel plates act as both formwork and primary reinforcement, and also as impermeable, blast and impact resistant membranes. The major duty of the shear connectors is to withstand longitudinal shear force and beam/slab separation, while in the bi-steel type where shear connectors are friction welded at both their two ends to two parallel steel plates, the longitudinal and transverse shear force, as well as plate buckling are resisted. The present paper highlights the previous prime researches concerning the subjects of SCSS composite construction, specifically on the conducted tests (push-out tests, tensile, direct shear tests, and bending tests) in which the components of partial interaction (uplift and slip forces) are resisted by various types of shear connectors.

Two-stage concrete (TSC), also known as prepacked aggregate concrete (PAC), differs from traditional concrete in terms of site application and manufacturing process. Although this type of concrete is not a replacement for conventional concrete applications, it is an ideal option for unusual and difficult placing conditions, especially for repairing existing concrete structures. In other words, this type of concrete is a newly developed concrete and made by placing and packing coarse aggregates and fibres in a designed formwork, then injecting a cement grout mixture into the free spaces between the aggregate particles using gravity or a pump device. For the mentioned system and others, concrete components used as floors or pavements must have an adequate degree of roughness during service life when exposed to skid and abrasion. Thus, this research work introduced a new concrete method (prepacked aggregates fibre-reinforced concrete—PAFRC) with high abrasion and skid resistance reinforced with waste polypropylene (PP) fibres from the carpet industry. The effects of PP fibres at 0–1% dosages on the mechanical properties, abrasion resistance, and skid resistance of PAFRC mixes were studied. The results revealed that the addition of PP fibres reduces the compressive strength of concrete mixtures. Nonetheless, the presence of PP fibres results in PAFRC mixes having higher tensile strength, abrasion resistance, and skid resistance than plain concrete. It was detected that in both grouting methods (gravity and pump), with the addition of PP fibre up to a specific dosage, the resistance against abrasion and skid was increased by about 26% compared to plain PAC mix. Additionally, the outcomes indicated that PAFRC is a promising material for applications such as pavements with high abrasion and skid resistance.

In this paper, the development process of a deployable modular sandwich panelized system for rapid-assembly building construction is presented, and its structural performance under some different action effects is investigated. This system, which includes an innovative sandwich panel and its integrated connections, can be used as structural walls and floors in quickly-assembled postdisaster housing, as well as load-bearing panels for prefabricated modular construction and semipermanent buildings. Panels and connections are composed of a pneumatic fabric formwork, and two 3D high-density polyethylene (HDPE) sheets as the skins, filled with high-density rigid polyurethane (PU) foam as the core. HDPE sheets manufactured with a studded surface considerably enhance stress distribution, buckling performance, and delamination strength of the sandwich panel under various loading conditions. The load-carrying behavior of the system in accordance with some American Society for Testing and Materials (ASTM) standards is presented here. The results show the system satisfies the codes’ criteria regarding semipermanent housing.

Dans le domaine du génie civil, la pulvérisation d'huile de décoffrage est devenue indispensable pour limiter le frottement et l'adhérence du béton sur les parois des coffrages. Leur utilisation sur site est contraignante car leur application est chronophage et polluante. Aujourd'hui, les enjeux résident dans le développement de nouvelles solutions alternatives aux huiles en s'appuyant sur les signatures surfaciques des parois coffrantes. Bien qu’un fort travail soit réalisé sur le développement d’huiles végétales écologiques, peu d’études analysent l'impact de ces signatures sur les phénomènes interfaciaux agissant entre le béton et le coffrage. Par conséquent, dans ce travail de thèse, le frottement du béton sur des parois coffrantes a été étudié dans un premier temps à l'aide d'un tribomètre plan/plan simulant les conditions de coulée du béton. Après avoir développé un essai instrumenté à l’échelle réduite du laboratoire permettant de reproduire le processus de décoffrage d'un voile sur site, l'adhérence du béton a été ensuite quantifiée sur différentes surfaces des parois de coffrage. L'analyse des données expérimentales et la caractérisation surfacique multiphysique des parois coffrantes permettent d'établir la fonctionnalité des signatures des parois sur le frottement et l'adhérence du béton. Ces corrélations sont utilisées pour proposer une solution de décoffrage innovante permettant d’éviter ses phénomènes à l'interface béton-coffrage
In the civil engineering industry, the formwork oil spraying has become essential to avoid the concrete friction and adhesion on the formwork skins. Their usage on site is limited because their application is time consuming and polluting. Nowadays, the challenges lie in the development of new alternatives to oils based on surface signatures of formwork skins. Even though a large amount of work investigates novel formulations for ecological oils, few studies investigate the effect of these signatures on interfacial phenomena acting between concrete and formwork. Thus, in the present thesis work, the concrete friction on formwork skins has been studied first using a plan/plan tribometer simulating the condition of concrete forming. After developing a small laboratory-scale instrumented test to reproduce the formwork removal process on site, concrete adhesion was secondly quantified. The analysis of experimental data and the multi-physics characterization of formwork surfaces make it possible to establish the functionality of the signatures of skins on the friction and the adhesion of concrete, respectively. These correlations are used to propose an ideal solution of formwork limiting these phenomena to the interface concrete-formwork

This Master's thesis "Multi-function building" deals with a project of new multi-function building. It is in a stage of project documentation. An object is design as a detached house. The house is slab-on-ground with four stories. In the object are designed 8 flats with 7 garages. In the first story is situated a wellness centre and an office. The roof is flat, projected as single-skin. A carrier system is made from sacrificial formwork system. A construction of a ceiling is projected as ribbed floor. Windows and entering doors are plastic, interior doors are wooden. A part of work is a specialization from a branch concrete structures.

AbstractThis research posits an innovative process of embedding carbon fibre as the primary structure within large-scale polymer 3D printed intricate architectural forms. The design and technical implications of this research are explored and demonstrated through two proto-architectural projects, Cloud Affects and Unclear Cloud, developed by the RMIT Architecture Snooks Research Lab. These projects are designed through a tectonic approach that we describe as a super composite – an approach that creates a compression of tectonics through algorithmic self-organisation and advanced manufacturing. Framed within a critical view of the lineage of polymer 3D printing and high tech fibres in the field of architectural design, the research outlines the limitations of existing robotic processes employed in contemporary carbon fibre fabrication. In response, the paper proposes an approach we describe as Infused Fibre Reinforced Plastic (IFRP) as a novel fabrication method for intricate geometries. This method involves 3D printing of sacrificial formwork conduits within the skin of complex architectural forms that are infused with continuous carbon fibre structural elements. Through detailed observation and critical review of Cloud Affects and Unclear Cloud (Fig. 2), the paper assesses innovations and challenges of this research in areas including printing, detailing, structural analysis and FEA modelling. The paper notes how these techniques have been refined through the iterative design of the two projects, including the development of fibre distribution mapping to optimise the structural performance.