Ultimate Behaviour of Trapezoidal Steel Sheets in Bending

A systematic analysis of existing trapezoidal steel sheets commonly used in the market is performed in order to compare their carrying capacity at the light of their ultimate behaviour. The complete investigation has been developed both from theoretical and experimental points of view. In this paper, the description of the experimental techniques, the numerical simulation of the obtained results as well as the exploitation of these data in order to check the codified design rules are reported

Study of Innovative Built-up Cold-formed Beams

In the present work innovative built-up cold-formed steel beams are presented. These are obtained by combining the pressing and cold-rolling forming techniques of steel sheets, along with the use of suitable connecting systems. Firstly, the beam shape features and the possible application fields, as well as the research project devoted to the assessment of their structural behaviour, are discussed. Then, experimental results concerning the characterization of both sheet material properties and connecting system performances are shown. In particular, the study of the sheet material is carried out by using an appropriate methodology of analysis, aiming at evaluating both mechanical and geometrical imperfections arising from the whole manufacturing process. At the same time, the mechanical behaviour of different connecting systems is investigated by means of several lap shear tests. The obtained results have provided useful design information and will be subsequently used to calibrate the numerical and theoretical models, addressing the prediction of the structural response of these innovative cold-formed beams

Experimental Response of Connections Between Cold-formed Steel Profile and Cememnt-based Panel

The seismic response of sheathed cold-f ormed steel (CFS) structures is highly influenced by the shear behaviour of panel-to-steel framing connections. Therefore, an experimental campai gn aiming at characterizing the shear behaviour of different sheathing-to-CFS profiles connections has been planed. In particular, the following objectives have been selected: to co mpare the response of different panel typologies (cement, wood and gypsum–based panels); to examine the effect of the loaded edge distance; to investigate the outcome of different cyclic loading protocols. This paper presents and discusses the main results of this experimental investigation carried out on cement-based sheathing- to-stud connections

Probabilistic time variant assessment of thin-walled steel members under atmospheric corrosion attack

Atmospheric corrosion is a relevant problem for steel structures and components exposed in aggressive environment in case of poor and/or unfeasible maintenance and inspection during service life. As for thin-walled members, the corrosion hazard can be exacerbated due to the thin thickness of components and the coupled effect between corrosion and buckling can significantly reduce the structural capacity of such structures. Following these considerations, this paper presents a study on the reliability of a thin-walled steel section subjected to the damage induced by atmospheric corrosion in outdoor environments, combining predictive corrosion models for metals with structural reliability applications. A general procedure for the evaluation of the time variant capacity is proposed and discussed in detail. Finally, an application to a C-lipped cold formed section is presented and a reliability analysis of the deteriorating section is carried out to evaluate the coupled effect of corrosion and buckling, according to the proposed procedure

Mechanical-physical experimental tests on lime mortars and bricks reinforced with hemp

Hemp is an agricultural product used for various applications. In the Civil Engineering field, only a limited use of this natural material, called the “green pig” since exploitation of all its constituent parts is allowed, has been done. For this reason, in the paper an experimental activity on lime mortars and bricks reinforced with hemp components has been performed. Compression and bending tests have been carried out on specimens manufactured with hemp shives and fibres, respectively. The achieved results have shown that hemp products change the failure modes from brittle to ductile, leaving basically unaltered the strength capacity of reinforced specimens with respect to unreinforced ones

Seismic Performance of Sheathed Cold-formed Shear Walls

The paper presents and discusses the results of a research on the seismic behaviour of cold-formed steel stud shear walls, sheathed with wood-based (oriented strand board) and gypsum-based (wallboard) panels. Within this activity, this paper provides the outcomes of the results of experimental (capacity evaluation) and theoretical (demand evaluation) phases of the research. Moreover, a contribution is given for the .evaluation of the strength reduction factor of this structural typology

On the Origin of I Beams and Quick Analysis on the Structural Efficiency of Hot-rolled Steel Members

In the current paper the origin of steel I beams has been analysed from historical-technological and structural points of view. First, the way leading to discover the most famous structural member of the modern Steel Engineering has been reconstructed. Later on, parameters of structural efficiency, allowing for a quick numerical evaluation of the effects produced by the rolling process on the semi-finished casting products, have been defined as a function of the difference in terms of weight between the solid billet and the member final shape on the basis of the more or less raw material centrifugation. By using the above mentioned structural efficiency parameters, the design criteria used for development of the European list of sections, with particular reference to IPE and HE profiles, have been comprehended. Finally, the proposed method, if applied to members having the same area, allows defining, without considering local buckling phenomena, the best profile for each performance category of steel members

Seismic vulnerability and damage of Italian historical centres: a case study in the Campania region

The preservation of masonry buildings typical of Italian historical centres represents a very pressing dilemma founded on recovery need of the urban fabric original character. In the paper, based on a methodology developed by some of the Authors on building aggregates, the seismic vulnerability estimation of some masonry compounds in the heart of the town of San Potito Sannitico (Caserta, Italy) is presented and compared to the results achieved from applying the basic literature method for isolated constructions. Finally, the damage scenario of inspected buildings has been shown by highlighting clearly the influence of different positions of structural units on the damages masonry aggregates suffer under different grade earthquakes, leading to individuate the most vulnerable buildings

Sustainability of Modular Lightweight Steel Building from Design to Construction

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