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Transfer relations represent analytical solutions of the linear theory of circular arches, relating each one of the kinematic and static variables at an arbitrary cross-section to the kinematic and static variables at the initial cross-section. The purpose of this paper is to demonstrate the significance of the transfer relations for structural analysis by means of three examples taken from civil engineering.

The first example refers to an arch bridge, the second one to the vault of a metro station and the third one to a real-scale test of a segmental tunnel ring.

The main conclusions drawn from these three examples are as follows: increasing the number of hangers/columns of the investigated arch bridge entails a reduction of the maximum bending moment of the arch, allowing it to approach, as much as possible, the desired thrust-line behavior; compared to the conventional in situ cast method, a combined precast and in situ cast method results in a decrease of the maximum bending moment of an element of the vault of the studied underground station by 46%; and the local behavior of the joints governs both the structural convergences and the bearing capacity of the tested segmental tunnel ring.

The three examples underline that the transfer relations significantly facilitate computer-aided engineering of circular arch structures, including arch bridges, vaults of metro stations and segmental tunnel rings.

Strategies for teaching engineering in the United Arab Emirates (UAE) have been evolving over the past decades due to innovations in technology, as well as the development of educational methodologies. In the recent past, the focus for engineering faculty has been not only on promoting the skills needed to raise the level of employability of Emirati graduates, but increasingly on new educational methodologies, e-learning and wireless networked laptop technology. Students in the UAE exhibit certain characteristics emerging from a variety of cultural and historical traditions, as well as from methodologies of education used at the pre-tertiary levels. These characteristics include expecting to be passive recipients of taught information, and lack of independence in their approach to problem solving. In this paper I discuss the development of strategies to facilitate the transition of students from passive to active learning; examine the role of technology-driven educational methodologies in promoting independent and group-centered learning skills; and use a case study to explore the instruction of Engineering Design and Computer-Aided Design (CAD) and to examine how classroom management techniques have changed as a result of the growing use of technology.

The construction industry’s daily processes demand heavy data usage and communication between project participants to meet client requirements. Thus, the application of information technology in project implementation has been increasing in the construction sector (CS) lately. However, the same cannot be seen in public sectors responsible for implementing government projects in South Africa. This study aimed to investigate the causes and effects of the underutilisation of information communication technology (ICT) in the building section of a public sector in a municipality in South Africa.

A qualitative approach was adopted for the study, using a public sector in one of the municipalities as a case study. Face-to-face interviews were conducted among the building unit workers, using unstructured interview questions. The data collected were analysed using the ATLAS.ti software.

The findings indicate a lack of understanding of existing and newly available ICT software and hardware technology among staff within the building technology due to lack of digitalisation in construction projects implementation, inadequate system upgrades, lack of adequate ICT resources, lack of financial resources for internet and software application subscriptions and lack of ICT training leading. The issues mentioned above have led to the outsourcing of projects professionals, slow pace of electronic emails, untrained professionals, usage of different and unlicensed software, resulting in the underutilisation of ICT within the whole building section. This change also adversely affects all officials, especially the junior officials who have graduated using the most recent ICT technology during their studies.

The building department of only one public sector was used for the study; therefore, the findings may not be generalisable. The case study public sector’s name is withheld for confidentiality purposes.

Adequate change management and continuous development, combined with the allocation of proper resources, would be necessary for all staff members. Enormous investments had to be made in the ICT equipment by providing a sufficient budget in the building section of the public sectors. The building section within public sectors should provide change management to all aged skills staff by attending seminars to learn new ICT technology applied within its work environment.

The study established the causes of the underutilisation of ICT in the CS, especially in the public work departments and municipalities, and how this contributes to service delivery.

Non-uniform rational B-splines (NURBSs) are the de facto standard for representing objects in computer-aided design (CAD). The purpose of this paper is to discuss how to stick to this standard in all phases of the additive manufacturing (AM) workflow, from the CAD object to the final G-code, bypassing unnecessary polygonal approximations.

The authors use a commercial CAD system (Rhino3D along with its programming environment Grasshopper) for direct slicing of the model, offset generation and trimming. Circular arcs are represented as quadratic NURBSs and free-form geometry as quadratic or cubic polynomial B-splines. Therefore, circular arcs are directly expressible as G2/G3 G-code commands, whereas free-form paths are rewritten as a succession of cubic Bézier curves, thereby admitting exact translation into G5 commands, available in firmware for AM controllers, such as Marlin.

Experimental results of this paper confirm a considerable improvement in quality over the standard AM workflow, consisting of an initial polygonization of the object (e.g. via standard tessellation language), slicing this polygonal approximation, offsetting the polygonal sections and, finally, generating G-code made up of polyline trajectories (G1 commands).

A streamlined AM workflow is obtained, with a seamless transfer from the initial CAD description to the final G-code. By adhering to the NURBS standard at all steps, the authors avoid multiple representations and associated errors resulting from approximations.