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The purpose of this study is to further investigate the potential benefits brought about by the development of modern technology in the steel construction industry. Specifically, the study focuses on the optimization of tapered members for pre-engineered steel structures, aligning with Eurocode 3 standards. By emphasizing the effectiveness of material utilization in construction, this research aims to enhance the structural performance and safety of buildings. Moreover, it recognizes the pivotal role played by such advancements in promoting economic growth through the reduction of material waste, optimization of cost-efficiency and support for sustainable construction practices.

Structural performance at initial analysis and final analysis of the selected critical frame were carried out using Dlubal RSTAB 8.18. The structural frame stability and sway imperfections were checked based on MS EN1993-1-1:2005 (EC3). To assess the structural stability of the portal frame using MS EN 1993-1-1:2005 (EC3), cross-sectional resistance and member buckling resistance were verified based on Clause 6.2.4 – Compression, Clause 6.2.5 – Bending Moment, Clause 6.2.6 – Shear, Clause 6.2.8 – Bending and Shear, Clause 6.2.9 – Bending and Axial Force and Clause 6.3.4 – General Method for Lateral and Lateral Torsional Buckling of Structural Components.

In this study, the cross sections of the web-tapered rafter and column were classified under Class 4. These involved the consideration of elastic shear resistance and effective area on the critical steel sections. The application of the General Method on the verification of the resistance to lateral and lateral torsional buckling for structural components required the extraction of some parameters using structural analysis software. From the results, there was only 5.90% of mass difference compared with the previous case study.

By classifying the web-tapered cross sections of the rafter and column under Class 4, the study accounts for important factors such as elastic shear resistance and effective area on critical steel sections.

Despite recognizing the significance of risk-based frameworks in fire safety engineering, the usual approach in structural fire design is largely member/component level, wherein effect of uncertainties influencing the fire resistance of structures are not explicitly considered. In this context, a probabilistic framework is presented to investigate the vulnerability of a reinforced concrete (RC) members and structure under fire loading scenario.

The RC structures exposed to fire are modeled in a finite element (FE) platform incorporating material and geometric nonlinearity, in which the transient thermo-mechanical analysis is carried out by suitably incorporating the temperature variation of thermal and mechanical properties of both concrete and steel rebar. The stochasticity in the system is considered in structural resistance, thermal and fire model parameters, and the subsequent fragility curves are developed considering threshold limit state of deflection.

The fire resistance of RC structure is reported to be significantly lower in comparison to the RC members, thereby illustrating the current prescriptive design approaches based on studies of structural member behavior to be crucial from a safety and reliability point of view.

The framework developed for the vulnerability assessment of RC structures under fire hazard through FE analysis can be effectively used to estimate the structural fire resistance for other similar structure to enhance safety and reliability of structures under such extreme threats.

The paper proposes a novel methodology for vulnerability assessment of three-dimensional RC structures under fire hazard through FE analysis and provides comparison of the structural fragility with fragility developed for structural members. Moreover, the research emphasizes to assume 3D behavior of the structure rather than the approximate 2D behavior.

This paper presents a robust numerical model for dealing with temporary instabilities which occur in the numerical analysis of steel structures under fire conditions. The model adopts the combined static-dynamic solution procedure to model ‘snap-through’ behaviour of industrial steel portal frame in fire. This new method allows solution procedure automatically switch between static and dynamic approaches, with the objective mainly for overcoming a transitory stage of instability in structural modelling. The current model is computationally very efficient compared to conducting full dynamic analysis of the structures for the whole duration of fire. The method could easily be applied for modelling composite and reinforced concrete buildings under fire conditions. The snap-through instability of the pitched portal frame has been modelled successfully by the new procedure. The method could provide a very useful modelling tool for the perform-based fire safety design of industrial buildings, as a much more realistic alternative to the highly simplified design methods which are currently in use.

Domain ontologies facilitate sharing and re‐use of data and knowledge between distributed collaborating systems. A major problem in the design and application of intelligent systems is to capture and understand: the data and information model that describes the domain; the various levels of knowledge associated with problem solving; and the patterns of interaction, information and data flow in the problem solving space. This paper reports the development of an ontology for agent‐based collaborative design of portal structures, using knowledge acquisition techniques and tools. It illustrates the application of the ontology in the development of a prototype multi‐agent systems. The study shows that a common ontology facilitates interaction and negotiation between agents and other distributed systems. The paper discusses the findings from the knowledge acquisition, their implications in the design and implementation of multi‐agent systems, and gives recommendations on developing agent‐based systems for collaborative design and decision‐support in the construction sector.

Physical phenomena interact with each other in ways that one cannot be analyzed without considering the other. To account for such interactions between multiple phenomena, partitioning has become a widely implemented computational approach. Partitioned analysis involves the exchange of inputs and outputs from constituent models (partitions) via iterative coupling operations, through which the individually developed constituent models are allowed to affect each other’s inputs and outputs. Partitioning, whether multi-scale or multi-physics in nature, is a powerful technique that can yield coupled models that can predict the behavior of a system more complex than the individual constituents themselves. The paper aims to discuss these issues.

Although partitioned analysis has been a key mechanism in developing more realistic predictive models over the last decade, its iterative coupling operations may lead to the propagation and accumulation of uncertainties and errors that, if unaccounted for, can severely degrade the coupled model predictions. This problem can be alleviated by reducing uncertainties and errors in individual constituent models through further code development. However, finite resources may limit code development efforts to just a portion of possible constituents, making it necessary to prioritize constituent model development for efficient use of resources. Thus, the authors propose here an approach along with its associated metric to rank constituents by tracing uncertainties and errors in coupled model predictions back to uncertainties and errors in constituent model predictions.

The proposed approach evaluates the deficiency (relative degree of imprecision and inaccuracy), importance (relative sensitivity) and cost of further code development for each constituent model, and combines these three factors in a quantitative prioritization metric. The benefits of the proposed metric are demonstrated on a structural portal frame using an optimization-based uncertainty inference and coupling approach.

This study proposes an approach and its corresponding metric to prioritize the improvement of constituents by quantifying the uncertainties, bias contributions, sensitivity analysis, and cost of the constituent models.

The purpose of this article is to present a conceptual model for the design of a scholarly web portal at the University of Tébessa, with which it is hoped that scholarly work stations that combine local and remote holdings, tools and documents will be created. Today, with access to enormous quantities of information facilitated by the web, boundaries between remote and local source documents become invisible. This is of extreme interest for libraries in Algeria, whose local holdings are very limited.

An outlined conceptual model of library portal architecture, with ontological classifications and relationships is presented. The model comes from applying literature reviews to the needs and specifications of the authors and leads to a detailed breakdown of the planning and implementation process.

Three findings in particular are worth noting. First, the contribution of web services to the seamless utility of a scholarly portal is indispensable: interoperable features, formats and protocols can be carefully customized. Second, the conceptual model assists not only in visualization but in implementation phases of the process from assessment of user needs and behaviors through interface creation and ongoing maintenance. Third, a method for recycling (or “porting”) existing applications in constructing new library services is a key component.

Though this library portal is conceived for an Algerian library, which will ultimately benefit from inclusion in a nationwide network, Réseau Régional Inter Bibliothèques Universitaires (RIBU), the conceptual model may guide anyone interested in aggregating online information resources into a single, seamless terminal.

This paper describes the results of non-linear elasto-plastic implicit dynamic finite element analyses that are used to predict the collapse behaviour of cold-formed steel portal frames at elevated temperatures. The collapse behaviour of a simple rigid-jointed beam idealisation and a more accurate semi-rigid jointed shell element idealisation are compared for two different fire scenarios. For the case of the shell element idealisation, the semi-rigidity of the cold-formed steel joints is explicitly taken into account through modelling of the bolt-hole elongation stiffness. In addition, the shell element idealisation is able to capture buckling of the cold-formed steel sections in the vicinity of the joints. The shell element idealisation is validated at ambient temperature against the results of full-scale tests reported in the literature. The behaviour at elevated temperatures is then considered for both the semi-rigid jointed shell and rigid-jointed beam idealisations. The inclusion of accurate joint rigidity and geometric non-linearity (second order analysis) are shown to affect the collapse behaviour at elevated temperatures. For each fire scenario considered, the importance of base fixity in preventing an undesirable outwards collapse mechanism is demonstrated. The results demonstrate that joint rigidity and varying fire scenarios should be considered in order to allow for conservative design.

The use of three non‐linear mathematical programming techniques for the optimization of structural design problems is discussed. The methods — sequential linear programming, the feasible direction method and the sequential unconstrained minimization technique — are applied to a portal frame problem to enable a study of their convergence efficiency to be studied. These methods are used for both the sizing of the structural members and determining the optimum roof pitch. The sequential linear programming method is shown to be particularly efficient for application to structural design problems. Some comments on the development of computer software for structural optimization are also given.

The purpose of this paper is to investigate the static and dynamic inelastic response of rigid and semi-rigid connections of steel structures with concrete-filled steel tube (CFST) columns built in high seismic areas, and to compare it with those with open section columns.

CFST columns are frequently used in moment resistant steel frames located in seismic areas due to their inherent advantages, including their ductility, energy absorption capacity as well as their high bearing capacity. The smart combination of steel and concrete makes it possible to benefit from the advantages of both components to the maximum. This research work presents the nonlinear dynamic response of moment resistant steel frames with CFST columns, with rigid or semi-rigid connections, built in high seismic areas, according to the Algerian seismic code RPA 99/2003, European EC8 and American FEMA 356 to show the nonlinear characteristics of this type of structures, and their advantages over steel frames with open section columns.

The paper presents the advantages of using CFST columns with rigid and semi-rigid connections on the seismic response of portal steel frames. A high performance level in terms of ductility, plastic hinges distribution and their order of appearance has been obtained. It also shows the low effect of seismic loading on the structural elements with CFST columns compared to structures with open section columns.

The investigation of the numerical results has shown the possibility of their use in the seismic areas for their adequate performance, and also with respect to the design limits specified in the seismic guidelines. In addition, this study represents a first step to develop seismic performance factors for steel structures with CFST columns in Algeria, where the Algerian code do not include a comprehensive specification for the composite steel structures.

The purpose of this paper is to analyze a new structural design applied in industrial frames using two type of steels (S275 and fire resistant (FR)) with different mechanical resistance against fire. To do it, the authors have taken into account variables such as intrinsic metallic design, span length, intumescent paint thickness, and fire time exposure, which offers information about new scenarios of design in industry.

The key methodology followed has taken into account a modeling program that uses the following variables: 25 and 35 m of span, 45 and 60 fire exposure times, and seven different intumescent paint thickness. An optimum structural design has been evaluated by discretization of each scenario with the particular type of steel, S275 and FR. The obtained approach could be a good guideline for future designs.

The results and analysis have shown a very good and valid idea of a new structural typology using optimum intumescent paint thickness into the final design of the industrial frame considering that it has two different types of steel. It is in realty a handicap since usually mechanical engineers employ structural steel without paying attention to this new feature.

Cheaper structural designs could be obtained using the two different types of steel considering the proper positioning into the full building.

The validity of design of two types of steel plus intumescent paint in building construction has been shown, and this study will encourage designers to use it, in particular in buildings with high fire risk.