Sizing optimization of trapezoidal corrugated roof sheeting, supporting solar panels, under wind loading

The dimensions of trapezoidal roof sheeting supporting solar panels are optimized so that a minimum amount of steel is required for a specific range of wind loads. Sheets of different grades and different thicknesses along with different ranges of wind speeds are considered. In order to simulate the behavior of the corrugated sheets analysis is carried out for two limit states: strength and serviceability. For both limit states, the objective is to minimize the weight per unit area of the panels. First, optimum cross-section is obtained to meet the strength conditions. Then the deflection is controlled for serviceability. The optimum dimensions for each steel grade and loading condition are determined. The optimization problem is formulated as a multi-objective problem that aims to minimize the section\u27s weight and maximize the section elastic modulus under the wind loading condition. A graph theory based approach is presented for the sizing optimization, employing an applied graph theory approach for the multi-objective all pairs shortest path problem. The proposed methodology addresses the sizing optimization problem to determine the geometry of the thin-walled cold-formed steel cross-sections that satisfy the design topological constraints

A parametric study on IBR sheeting supported by purlins

A dissertation submitted to the Faculty of Engineering and the Built Environment, University of the Witwatersrand, in fulfilment of the requirements for the degree of Master of Science in Engineering Johannesburg, 2016This dissertation presents a parametric study conducted on the dimensions of an inverted box rib (IBR) sheet. The objectives of the study were (i) to obtain the optimum dimensions that would be used to simulate new IBR profiles made from standard sheet input coils whilst meeting the stiffness criterion; and (ii) to perform a cost analysis to determine the most economic simulated profile. The dimensions which were varied in the parametric study were rib-height, rib-width, sheet thickness and the number of pans per 686 mm cover width of a single IBR 686 sheet. Numerical experiments were conducted using the Finite Elements Method and Abaqus/CAE software. The results were compared to the predictions obtained from Euler-Bernoulli beam theory. The outputs from the experiments were the sheet deflection from which stiffness was determined, and eigenvalues from which the profiles’ stability and buckling modes were calculated. This study found that sheet stiffness increased as the rib-height, sheet thickness and number of pans per 686 mm cover width increased. In contrast, the rib-width had little effect on the sheet stiffness. Hence, it was concluded that, for any IBR sheet profile, the rib-width should be kept at approximately 23 mm to avoid using more material in the sheet. The optimum dimensions found were rib-height of 34 mm, rib-width of 23 mm and four pans per 686 mm cover width. The commercially available IBR 686 sheet is made up of four pans and has a rib-height and a rib-width of 37 and 33 mm, respectively. It is manufactured from an input sheet coil of 925 mm. Reducing the rib-height from 37 mm to 34 mm and the rib-width from 33 mm to 23 mm resulted in increasing the cover width by 8 %. The optimum dimensions were further used to simulate profiles made from the 925, 940, 1000, 1175, 1219, 1225, 1250 and 1320 mm standard sheet coils in order to find the most economic IBR profiles that met the stiffness criterion. The 1250 mm coil yielded the most economical IBR profile, which has six 97 mm wide pans, and a 996 mm cover width. This profile resulted in a 10 % cost saving compared with the next closest profile.MT201

DESAIN BARU PADA PENERANGAN JALAN DENGAN PENDEKATAN HOMOGENIUSES LUMINAIRES DAN NON-HOMOGENIUSES

Proses pergantian teknologi penerangan jalan umum (PJU) dari lampu high pressure sodium (HPS) menjadi lampu Light Emitting Diode (LED) sering kali mengalami kesalahan desain, yang berakibat tidak menghasilkan efisiensi energi yang sesuai harapan. Penelitian ini bertujuan untuk melakukan proses desain ulang PJU yang sudah menggunakan teknologi LED dengan menggunakan pendekatan Homogeniuses dan Non-Homogeniuses Luminaires. Studi dilakukan pada sebuah ruas jalan di kota Bandung yang memiliki Panjang 734 meter, dengan jumlah tiang lampu LED sebanyak 16 buah. Proses desain ulang menggunakan perangkat lunak open source DIALux Evo 8. Simulasi yang dilakukan memberikan hasil bahwa pendekatan Homogeniuses Luminaires lebih baik dalam hal penggunaan energi dan lebih ekonomis dari pendekatan Non-Homogeniuses Luminaires, karena dapat mereduksi kebutuhan jumlah tiang yang diperlukan, dan menghasilkan pencahayaan yang sesuai SNI. Proses desain PJU yang baik harus mempertimbangkan aspek teknis dan pembiayaan yang tepat dapat memberikan keuntungan bagi pengguna jalan dan pemerintah kota. The process of changing roadway lighting technology from high pressure sodium lamps to Light Emitting Diode (LED) lamps often experiences design errors, which results in not producing energy efficiency as expected. This study aims to conduct a process of redesigning PJU that has used LED technology using a homogeniuses and non-homogeniuses luminaire approach. The study was carried out on a road in the city of Bandung that has a length of 734 meters, with the number of LED light poles as many as 16. The simulation results show that the Homogeniuses Luminaires approach is better in terms of energy use and more economical than the Non-Homogeniuses Luminaires approach, because it can reduce the need for the number of poles needed, and produce lighting that according to SNI. A good PJU design process must consider the technical aspects and the right financing can benefit road users and the city government

Optimisation and Decision Support during the Conceptual Stage of Building Design

Merged with duplicate record 10026.1/726 on 28.02.2017 by CS (TIS)Modern building design is complex and involves many different disciplines operating in a fragmented manner. Appropriate computer-based decision support (DS) tools are sought that can raise the level of integration of different activities at the conceptual stage, in order to help create better designs solutions. This project investigates opportunities that exist for using techniques based upon the Genetic Algorithm (GA) to support critical activities of conceptual building design (CBD). Collective independent studies have shown that the GA is a powerful optimisation and exploratory search technique with widespread application. The GA is essentially very simple yet it offers robustness and domain independence. The GA efficiently searches a domain to exploit highly suitable information. It maintains multiple solutions to problems simultaneously and is well suited to non-linear problems and those of a discontinuous nature found in engineering design. The literature search first examines traditional approaches to supporting conceptual design. Existing GA techniques and applications are discussed which include pioneering studies in the field of detailed structural design. Broader GA studies are also reported which have demonstrated possibilities for investigating geometrical, topological and member size variation. The tasks and goals of conceptual design are studied. A rationale is introduced, aimed at enabling the GA to be applied in a manner that provides the most effective support to the designer. Numerical experiments with floor planning are presented. These studies provide a basic foundation for a subsequent design support system (DSS) capable of generating structural design concepts. A hierarchical Structured GA (SGA) created by Dasgupta et al [1] is investigated to support the generation of diverse structural design concepts. The SGA supports variation in the size, shape and structural configuration of a building and in the choice of structural frame type and floor system. The benefits and limitations of the SGA approach are discussed. The creation of a prototype DSS system, abritrarily called Designer-Pro (DPRO), is described. A detailed building design model is introduced which is required for design development and appraisal. Simplifications, design rationale and generic component modelling are mentioned. A cost-based single criteria optimisation problem (SCOP) is created in which other constraints are represented as design parameters. The thesis describes the importance of the object-oriented programming (OOP) paradigm for creating a versatile design model and the need for complementary graphical user interface (GUI) tools to provide human-computer interaction (HCI) capabilities for control and intelligent design manipulation. Techniques that increase flexibility in the generation and appraisal of concept are presented. Tools presented include a convergence plot of design solutions that supports cursor-interrogation to reveal the details of individual concepts. The graph permits study of design progression, or evolution of optimum design solutions. A visualisation tool is also presented. The DPRO system supports multiple operating modes, including single-design appraisal and enumerative search (ES). Case study examples are provided which demonstrate the applicability of the DPRO system to a range of different design scenarios. The DPRO system performs well in all tests. A parametric study demonstrates the potential of the system for DS. Limitations of the current approach and opportunities to broaden the study form part of the scope for further work. Some suggestions for further study are made, based upon newly-emerging techniques

INTER-ENG 2020

These proceedings contain research papers that were accepted for presentation at the 14th International Conference Inter-Eng 2020 ,Interdisciplinarity in Engineering, which was held on 8–9 October 2020, in Târgu Mureș, Romania. It is a leading international professional and scientific forum for engineers and scientists to present research works, contributions, and recent developments, as well as current practices in engineering, which is falling into a tradition of important scientific events occurring at Faculty of Engineering and Information Technology in the George Emil Palade University of Medicine, Pharmacy Science, and Technology of Târgu Mures, Romania. The Inter-Eng conference started from the observation that in the 21st century, the era of high technology, without new approaches in research, we cannot speak of a harmonious society. The theme of the conference, proposing a new approach related to Industry 4.0, was the development of a new generation of smart factories based on the manufacturing and assembly process digitalization, related to advanced manufacturing technology, lean manufacturing, sustainable manufacturing, additive manufacturing, and manufacturing tools and equipment. The conference slogan was “Europe’s future is digital: a broad vision of the Industry 4.0 concept beyond direct manufacturing in the company”