Papers by Keyword: Structural Design

Abstract: This study explores the role of Computer-Aided Design (CAD) in advancing sustainable structural design, focusing on a portal frame warehouse as a case study. As construction demands shift towards sustainability, CAD tools such as AutoCAD, ProtaStructure, and Tekla Structures offer enhanced precision, design optimization, and material efficiency. The research compares manual method and CAD-based approaches in designing a 20 m × 50 m steel portal frame warehouse, following BS 5950 standards. The portar frame design involved manually analysing loads, selecting sections, and designing columns, base plates, and footings, while CAD softwares performed 3D modelling and automatic code checks. After the analysis and design, 203×203×46 UC (276 kg) was obtained at a rate of ₦331,200/section for manual approach, while with CAD approach, 254×254×73 UB (438 kg) at a rate of ₦525,600/section was obtained. However, for the footing. 0.216 m³ at ₦9,720 was obtained for manual approach, while 0.8 m³ at ₦23,040 was obtained for CAD approach. In total, for a section, manual design will cost ₦653,398 while CAD design cost will ₦864,814. It is recommended that CAD-based design should be prioritized for large-scale or safety-critical infrastructure due to its precision, efficiency, and compliance with modern codes. For smaller or budget-limited projects, a hybrid approach combining manual and CAD methods is suggested. Investment in CAD training and software can drive long-term sustainability and structural resilience.

Abstract: Abrasive water jet surface cleaning technology offers advantages such as low energy consumption, high cleaning rate, and cost-effectiveness. It can effectively meet the surface cleaning requirements of complex curved metal parts and composite materials, presenting promising applications in the fields of remanufacturing and precision machining. This study specifically focuses on the design of an abrasive water jet surface coating removal device for metal structural components. To address the issue of abrasive jet wear on sealing structures, a rotating pipeline approach is employed. This innovative device allows for adjustments in the jet incidence angle and rotation radius. A simulation model is developed to predict removal rates by MATLAB/Simulink. And an experimental system is established to validate the functionality of the removal actuator, demonstrating a maximum removal rate of 34.2mm²/s at jet pressure of 5 MPa. This research contributes to enhancing the efficiency of removing surface coatings from structural components and provides valuable theoretical guidance for the planning of coating removal paths for actuators.

Abstract: Researchers have become interested in functionally graded concrete (FGC) in recent years due to its potential to enhance the desired performance. Functional gradation can be carried out in a continuous or stepped/layered manner. Most studies have been conducted on two layered FGC beams by substituting the richer mixes in either tension or compression zone. Previous studies have incorporated and presented the structural design approach of such two-layered beams. Moreover, the layer in the compression zone was assumed to bear entire compressive stresses. Previous studies exhibited savings in cement by up to 37% using a layer of the concrete class defined by exposure conditions around reinforcement and the concrete of minimal structural class. However, using structural concrete of minimal class in the remaining segments may result in a higher reinforcement requirement, reducing the benefits of savings in embodied CO₂ offered by reduced cement consumption. This paper examines how designing the beam as a Functionally Graded Reinforced Concrete (FGRC) beam following Indian Standard 456:2016 affects the cost and embodied CO₂ based on cement and steel consumption through the durability approach of design, wherein the substitution of the layer is considered in the tension zone. The study revealed that a 10% and 16% reduction in cost and embodied CO₂ could be accomplished.

Abstract: The element of zirconium (Zr) belongs to the same group 4 as Ti in the periodic table. Therefore it possesses similar chemical properties. The Ti-Zr binary system forms a continuous solid solution for both high temperature β phase with the body centered cubic (BCC) structure and low temperature α phase with the hexagonal close-packed (HCP) structure throughout the entire range of composition. As is well known, on the other hand, the element of iron (Fe) is not only inevitable but also effective element in Ti.By incorporating Fe at the stage of alloy design, off-grade sponge titanium can be employed. Both elements seem to be effective in strengthening the titanium alloys. The purpose of this work was to prepare Ti-Zr-Fe alloys and then mechanical property and heat treatment behaviours were investigated as a fundamental research. Ti-x mass% Zr-1mass% Fe alloys (x=0, 5, 10) were melted in a laboratory-scale arc furnace under a high purity argon atmosphere from the sponge Ti, the sponge Zr and the Fe wire. The resulting ingots were hot forged and rolled at approximately 1120 K to obtain plates of approximately 2 mm in thickness. Well-mixed and homogeneous samples could be obtained, oxygen contaminations were less than 0.09 %. Solid solution of Zr into Ti was confirmed by the XRD peak shift in α phase. Vickers hardness and proof stress increased with Zr content. No remarkable changes could be observed in the microstructures after the solution treatment at 1173 K. However, Young’s modulus increased at x=10 by the treatment.

Abstract: It is important to improve dynamic performance of rotating machinery by reducing the mass of shaft and increasing the natural frequency. Many studies have focused on dynamic characteristics of shaft in rotating machinery with the utilization of composite material. This paper mainly investigates the structural design and dynamic analysis of a CFRP/Metal hybrid shaft. The finite element method (FEM) has been used to determine the selection of design variables include fiber orientation angle, layers stacking sequence and layers thickness. Also, experimental test was carried out using a FFT analyzer with impact hammers. The differences between the FEM analysis result and the experiment test result were respectively less than 4.5% and 6.3% for the first two natural frequencies; therefore, the results of FEM analysis are acceptable. The results reveal that the fiber orientation angle is the most significant factor affecting the dynamic characteristics of CFRP/Metal hybrid shaft. In addition, there have some effect of the layer stacking sequence on natural frequency.

Abstract: SMPC (shape memory polymer composites) has many advantages as a hinge of spacedeployable antenna. The structure of the SMPC hinge is designed and tested in this paper. The basicmechanical properties of composites are calculated. Through finite element simulation, the bendingmoment of the positive and reverse of the lamella with the bending angle as the lamella with the fiberdifferent content, the bending of the lamella with different bending distances was simulated, and thecurves of bending moment with bending angle in different bending distances were obtained. Hingebending process simulation shows when the hinge begins to bend, the stress of the inner positivebending lamella is larger. The stress of the outside bending lamella increases with the increase of thebending angle. As for the relationship of moment-angle, the process of unfolding of the hinge isbasically the same as that of the lamellae. However, the hinge bending moment is much greater thanthe single layer lamella bending moment. The hinge with the structure of back-to-back can increasethe structure stiffness and the bending resilience ability. The tested moment of the hinge is similar tothe simulation result.

Abstract: The SMPC (Shape Memory Polymer Composite) is used for space deployable structuredue to their excellent properties. In this paper, the space deployable antenna was designed, whichincludes the design of the basic configuration, the antenna substrate, the SMPC hinge and its location.The modal of the hinge was studied with finite element software ABAQUS. The hinges with differentthickness were analyzed and compared. The modal of single piece antenna was calculated. Thevibration types and natural frequencies of the single piece antenna in connection are obtained. Theeffects of different hinge structures on the overall mode and the natural frequencies of the hinge werestudied. The influence of hinge location on the natural frequencies of deployable antenna was alsostudied. The mode of four pieces antenna in unfolding was calculated, the main vibration types wereobtained, and the natural frequencies were analyzed and compared with that of the single pieceantenna. In unfolding, the natural frequencies of the four pieces antenna are lower than that of thesingle piece one.

Abstract: In order to study the forming quality of AlSi10Mg powder for SLM process without supporting structure, as well as lay the foundation of subsequence structural design of Aluminum SLM technique, a series of typical coupons have been designed and printed. Based on comprehensive consideration of layout direction, overhang angle, hole size, etc., Xline 2000R with optimized process parameter has been used as SLM equipment for AlSi10Mg powder. Through the analysis of printed coupons, the beneficial conclusion is made which can be used to guide future design, especially for the structure with complex shape.

Abstract: The existing metallic solutions used for vertical traffic signs are associated with higher costs and environmental issues due to their manufacturing and degradation, when compared with polymeric solutions. Thus, the development of vertical signs considering the injection from polymeric materials in order to overcome problems related with sustainability, maintenance costs, and to achieve higher resistance to corrosion assumes nowadays an important role. The use of eco-friendly and innovative products considering the industrial waste combined with synthetic polymers performing the appropriate mechanical properties, can also be studied to find out new solutions that allow to solve the aforementioned problems. Additionally, these innovative vertical signs can contribute to avoid vandalism events related with theft and graffiti activities. This work presents the prior materials investigation and the structural design of vertical signs that are intended to be produced through polymer injection. Three main steps were considered: i) materials research, ii) materials characterisation through the analysis of polycarbonate resin isolated and in different sets of mixtures with different concentrations through tensile testing and static water contact angle measurements to find the optimal material composition; and iii) structural numerical simulation considering polycarbonate resin and using the current standard EN 12899-1 [1] to compute wind resistance, temporary and permanent deflections. Both experimental and numerical results led to an optimized proposal of the vertical signposting structural design.

Abstract: This work is to design a high efficiency composite vertical axis wind turbine blade which is applicable to relatively low speed region. In the aerodynamic design, the parametric study is carried out to find an optimal aerodynamic configuration having high efficiency in both low and high wind speed region using the proposed design procedure. In the structural design, the blade adopts the skin-spar-foam core sandwich structure concept. The glass fabric/epoxy composite material is used for both skin and spar. The designed configuration is repeatedly modified by structural analysis results using a finite element analysis method. Finally, the strength and damage test of designed blade was conducted. In order to evaluate the test results, it was compared with estimated results. According to comparison results, the estimated results were well agreed with the experimental results.