Papers by Keyword: Steel Structures

Abstract: This study applies Life Cycle Assessment (LCA) using OpenLCA software in accordance with ISO 14040/14044 standards. A two-story school building was modeled with reinforced concrete and structural steel systems, both designed using ETABS. The study looks at a two-story school building over several phases, such as getting materials, making them, building them, using them, and then getting rid of them. Key performance indicators such as carbon emissions, energy consumption, recyclability, and construction waste are analyzed. Results reveal that concrete structures emit 27% less CO₂ and consume 55% less energy than steel systems, though steel offers superior recyclability (98%). The results show that steel structures may be recycled and used again and again, whereas reinforced concrete uses substantially less energy and carbon. The study proposes the use of hybrid systems that combine concrete slabs and foundations with steel superstructures to actualize these results. It also proposes employing materials that are good for the environment, such fly ash and recycled aggregates, and establishing national databases to assist people choose products. These suggestions are a practical way to get Iraq to embrace green building laws and practices.

Abstract: The article presents and describes the methodology for determining the fire resistance limit state of loaded thermally stressed steel floor beams. The article describes the methodology for taking into account the uneven temperature distribution along the height of the cross-section of a fireproofed steel floor beam. The author presents a method for refining the stiffness characteristics of an I-beam after exposure to high temperatures from a fire and compares the results with the results of field tests.

Abstract: The application of modular systems is one of the new technologies worth considering. The modular system is a prefabricated steel structure where the floor decks, columns, beams, and walls are fabricated along with the utility system, mechanical-electrical, and finishing in one modular. The benefits of this system are constructability, positive aspects towards schedule, fewer on and off-site workers, quality and productivity aspects, and proper tests. A total solution is needed in the form of steel-based construction modular growing houses to support the National Development Program. Joint research is needed between Universities and Local Industries to produce technological innovations with high Domestic Component Levels in implementing the use of materials and steel manufacturing processes. The Krakatau Steel-Institut Teknologi Sepuluh Nopember (KSITS) Steel Modular Growing House Design is a steel-based construction that supports in a fast, precise, quality manner; and becomes a contributor in absorbing various locally produced steel products. From the analytical study and modeling of steel modular, the results showed that KSITS Steel Modular Growing House Design has fulfilled the requirements of structural and connection strength, serviceability control, management construction procedures, economical engineering, and manufacturing design in operational planning for the short-term and development of local steel technology downstream industries in the future. The results showed minor differences in ratios, with WF steel slightly surpassing HSS steel. HSS steel stands out due to its significantly lighter weight compared to WF steel, impacting structural dynamics and feasibility in modular house construction. This indicates that the moment capacity of HSS is lower than the moment capacity of WF. However, from the results of running, it is found that the criteria are the same, all components other than the beam, do not experience yielding prior to yielding in the beam. It means that the connection works properly according to the criteria.

Abstract: Friction stir welding is a relatively new technique, which, due to its advantages, has been continuously developed and applied to industrial applications. Friction stir spot welds (FSSW) are one variant of friction stir welding (FSW) where the traverse part of the FSW process is eliminated, i.e., the tool is only plunged into the material and retracted. The resulting weld is a point or “spot” weld. This process of joining materials in solid state is an extremely complex one because of the physical phenomena that occur during the process, which makes the research still in full development. The paper presents an analysis of recent scientific work on the use of the FSSW process for the joining of steel structures. Thus, this study analyses the types of steel and joined structures, the process parameters used in experimental research, and the mechanical properties of FSSW joined steel structures. The main conclusions of the studied papers are summarized and the main research directions on the steel structures joined by the FSSW process are identified.

Abstract: The article considers and analyses the methods by which it is possible to carry out research to determine the fire resistance of elements of steel frames of industrial buildings. It is determined that it is expedient to use the means of computational fluid dynamics, which has no limitations due to the high cost, complexity, environmental friendliness and complexity in comparison with real experiments. In order to conduct the most reliable computational experiments, mathematical models of temperature and mechanical reaction to the thermal effect of fire were created, taking into account the equations of thermal conductivity, systems of differential equations of stress-strain state of solids in their numerical implementation based on the finite element method. The solution of mathematical models was carried out using computational fluid dynamics, which describes the process of heat and mass transfer in test fire furnaces during the determination of fire resistance of steel structures. According to the results of computational experiments it is shown that the limiting state of loss of bearing capacity of vertical and horizontal structures occurs due to the formation of a zone of plastic deformations taking into account the associative theory of plasticity. According to the results of computational experiments, the dependence of the limit of fire resistance on the level of applied load to structures, which is close to linear, was revealed. Based on the obtained dependences and the corresponding graphs, a technique is developed based on the use of maximum deformations of the elements with the corresponding fixation of the limit state on the loss of fire resistance in terms of bearing capacity by bending this curve.

Abstract: The article presents the results of a study of use thermographic non-destructive testing to search for cracks in steel structures. Theoretical substantiation of thermal non-destructive method of control for detection of cracks in steel structures. A practical study proving the possibility of using thermal non-destructive testing to detect cracks in steel structures is described. The problems that arise during the thermal non-destructive method of control and possible ways to solve them. The authors conclude that the method of thermographic control can be used during the inspection of steel structures for qualitative assessment of cracks.

Abstract: Friction stir welding is a relatively new technique, developed in 1991, which, due to its advantages, has been continuously developed and applied to industrial applications. This process of joining materials in solid state is an extremely complex one because of the physical phenomena that occur during the process, which makes the research still in full development. The paper presents an analysis of recent scientific work on the use of the FSW process for the joining of steel structures. Thus, the types of steels and merged structures, the processes used and the technological parameters used are analyzed. On the basis of this analysis, the main conclusions of the studied works are summarized and the main development directions for research on the FSW process of steel structures are identified.

Abstract: A railway bridge over several decades will be degraded due to localized corrosion. As a result, the load capacity of the bridge decreases, especially under the live load caused by trains. This paper examines the residual load capacity of a bridge deteriorated by localized corrosion by using the multibody dynamics approach. This approach allows an accurate description of the interaction between trains and bridges. At the same time, it allows the formation of corrosion marks on each structural member of the bridge in a numerical model precisely based on actual measured data. In order to describe accurately the remaining load of the bridge under the moving load of the train, a dynamic testing and finite element modeling of a steel bridge are conducted and compared. At the same time, the results are also compared with the simulation results of the bridge model before being corroded. In addition, the paper also tests the reliability of the numerical model for assessments of similar bridges without actual measurement results that are costly and time-consuming.

Abstract: Calculations on the example of a steel column showed that with the combined effect of an explosion that causes deformation and subsequent fire, even without damaging the fire-retardant coat, there is a significant decrease in the fire resistance of the structure due to a decrease in the critical temperature. It is shown that, on the basis of the methodology proposed in this work, for hazardous operations industrial facilities, it is possible to predict the stability of steel columns in crash explosions followed by fire, as well as to recommend the values ​​of workloads and parameters of fire-retardant coats providing the necessary stability. It is also shown that when calculating the fire resistance limit of a steel structure with intumescent fire-retardant coat, it is necessary to take into account the proper heating time of steel structures until they lose strength.

Abstract: The paper will try to evidence the importance and the role of the Welded Structural Designer and explain also the critical joints to the dynamically loaded welded structures susceptible to fatigue. In case of the important structures the decision of the Welded Structural Designer is essential, because his decision allows the change the type of joints, the type of materials.