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Adobe masonry (AM) dwellings are a considerable portion of existing buildings stock worldwide, particularly in developing countries. Several earthquakes occurred during last decades dramatically showed a high seismic vulnerability of such constructions, which are not generally engineered. Therefore, several research groups have been involved in the investigation about effective and viable retrofitting solutions for AM buildings. Currently, most of studies available in literature addressed the issue by means of experimental programs consisting of dynamic or static tests on reduced- or full-scale specimens, representing partial or complete AM dwellings. Nevertheless, in those works, limited or no attention was generally paid to the crucial issue of the spatial variability of material properties within AM, which can produce critical forms of mechanical response and premature failure. In this study, three series of seven AM wallets were tested under monotonic diagonal compression load: one series consisted of unreinforced specimens (used as benchmark) and the remaining series were strengthened with two textile reinforced matrix (TRM) systems, made of either hemp or glass meshes. Masonry joints and matrix were produced using the same mud mortar, which is a typical mortar of existing Italian AM buildings. Experimental outcomes of tests in terms of observed damage and response curves are presented, along with a comprehensive characterization of mortar and bricks. Then, with the aim to draw out general and robust trends about TRM effectiveness as strengthening solution in the improvement of shear strength and ductility capacity, the response variability was quantitatively investigated via statistical analysis of recorded stress–strain samples.

The advancements of additive manufacturing (AM) technologies are typically coupled with research addressing topology optimization, whose aim is to use optimization methods to achieve effective expressions of free-form design. While many studies emphasize the breakthroughs that topology optimization could bring into structural engineering, there are just a few scientific contributions that address design feasibility, accounting for the technological constraints that characterize the different AM techniques. By formulating a stress-constrained topology optimization problem with a more technologically oriented approach, this study aims to optimize concrete structures while enforcing the cross-section width and path-traceability restrictions that affect the feasibility and performance of geometries obtained through the layered extrusion technique. In particular, this paper proposes a curve-based Biased Random-Key Genetic Algorithm that optimizes stress-constrained structures and generates topologies that can be implemented without post-processing operations. The proposed algorithm, when tested on a diverse set of concrete beam configurations, effectively achieved optimized solutions that used between 81 % and 75 % less material than the full beam configuration. Additionally, each one of the designed topologies adequately met the stress requirements and process-specific constraints. Lastly, two experimental cases also highlighted the printability effectiveness of the proposed approach in conjunction with design of optimized solutions.

Irregular frame structures can exhibit an inefficient dynamic behavior, such as undesirable torsional effects and asymmetric displacements, that can severely affect structural performances in case of a seismic event. To mitigate the influence of geometric irregularities, the pre-dimensioning of structural elements is crucial to achieve the best possible seismic behavior. Identifying the optimal solutions in terms of elements’ cross-sections and orientations is a non-trivial problem that in general designers tackle following trial-and-error attempts which can become numerous in the most complicated cases. This paper formally describes the pre-dimensioning problem and presents a Learn-heuristic that hybridizes a Genetic Algorithm and a k-Means algorithm procedure for its solution. The algorithm is validated on a diverse set of 3D reinforced concrete structures and through a Structural Pre-dimensioning challenge, where the performances of the algorithm are compared against those accomplished by a group of Ph.D. candidates. The computational results evidenced that the proposed optimization framework achieves pre-dimensioning solutions that significantly improve the designs provided by the Ph.D. students, thus suggesting a favorable inclusion of the proposed solution method in classical pre-dimensioning processes.

Regulatory activity concerning the management of existing bridges has recently been affected by updates, for instance, in Italy, which calls for a speedy and pragmatic approach based on new technologies such as building information modeling (BIM), when dealing with the survey and risk classification as well as the evaluation and monitoring of structural safety. This paper focuses on the development and integration of a digital solution, based principally on the specific framework developed by the authors, which supports BIM modeling and information management activities, in the structural setting under investigation, through the use of several technologies and tools, namely BIM-authoring, CDE platform and visual programming, in addition to programming in Python. Starting from the organization of a specific BIM object library and the initial data, inserted by means of a custom-made input environment, it was possible to reproduce digital models of bridges in accordance with specific information requirements following the new Level of Information Need setting. The applicability of the proposal is tested on two judiciously chosen real-life cases with different characteristics. Through this implementation, a series of advantages emerge, including expediting traditional procedures for BIM modeling, accessibility and traceability of information—which are constantly updated to support the monitoring of structural safety over time—and the decision-making process related to the bridge management context.

In the field of infrastructure, the development and application of the openBIM (open Building Information Modeling) approach and related standards (principally Industry Foundation Classes) remain limited with regard to processes in O&M (Operation and Maintenance) phases, as well as the broader context of AM (Asset Management). This article deals with the activities carried out as part of a pilot project based on the need to manage the operation and assess the condition and value of existing infrastructure along the Cancello–Benevento railway line. The principal goal was to systematize information by digitalizing the infrastructure, in order to enable the assessment of possible performance gaps (compared to national railway standards) in the event of integration within the national infrastructure. In compliance with the project requirements, a digitalization strategy was designed for the definition of surveying activities and the implementation of openBIM systems for the development of an object library and a federated digital model, structured within the collaborative platform that was used, and allowing management, maintenance, and subsequent financial evaluation in the broader context of asset management. The project involved the collaboration of railway operators, a university, and a software company that implemented innovative concepts concerning IFC (specifically, IFC4x2 was used) through the development of dedicated software solutions. The digital solution we proposed enabled the use of digital models as access keys to survey and maintenance information (ERP platforms used by the railway operators) that was available in real time. This project was nominated at the buildingSMART awards 2021 and was one of three finalists in the “Asset Management Using openBIM” category.

With the introduction of the BIM methodology, the digitalization is consolidating mostly the process of new building design defining new standardized working procedures in order to optimize the data flow. On the contrary, pertaining to existing buildings, the rules are still dictated by the traditional methodology leading to fragmented and disaggregated information flow. However, some tools have been recently developed and are quickly upgrading to meet the specific aim to pursue progress, dynamism and experimentation in order to stay in tune with market demands. One common issue, is due to the fact that the documents are paper, hard to find and numerous so that the digitalization represents the best real solution to improve their management. In this regard, the heart of the informative flow is represented by the Common Data Environment (CDE), a cloud storage in which the documents are collected once uploaded and easily manageable with specific platforms. By way of example, a case study is developed in the paper in which the management process of the H-BIM of the XV century’s structure placed in the old town of Naples is carried out in a digital way, through the usBIM.platform (released by ACCA software company) using specific tools, like links, markers and tags. The goal of the paper is to define both a new organization for the data archive, in which the documents are structured and easily traceable, both a new way of conceiving the BIM model that it is thought as an informative vehicle and a key access to the information rather than a mere geometric representation.

Reinforced concrete (RC) structures built before the 1970 represent a large portion of the existing European buildings stock. Their obsolescence in terms of design criteria, materials, and functionality is becoming a critical issue for guaranteeing adequate compliance with current structural codes. Recently, a new jacketing system based on the use of high-performance fiber-reinforced concrete (HPFRC) has been introduced for strengthening existing RC building members. Despite the promising aspects of the HPFRC jacketing technique, currently, a comprehensive and systematic technical framework for its implementation is still missing. In this paper, the experimental performance of RC columns strengthened with the HPFRC jacket subjected to pure axial load and combined axial load-bending moment uncoupled from shear is investigated. The test outcomes confirmed a significant improvement of the structural performance for the strengthened columns, especially for higher values of eccentricity. Finally, a standard-based practice-oriented analytical tool for designing retrofit interventions using the HPFRC jacket is proposed. The comparison between the calculated and experimental results revealed a satisfactory prediction capability.

The process of constructing structural systems produces a huge amount of documentation that traces human activities on a construction site. While the building information modelling approach introduces common data environments (CDEs) to support document management, communication between them is limited, and mainly involves the use of email and activities susceptible to human error. This paper proposes a proof-of-concept for the integration of blockchains and smart contracts into information flows used in various CDEs. The focus of the proposal is on reducing human error and increasing the reliability and transparency of decision-making processes on construction sites pertaining to the structural system. To this end, the proof-of-concept introduces smart contracts that have different levels of complexity, with the advanced version comparing information exchanged with data gathered by IoT sensors on site. A first implementation of the proposal is also presented.

Many people live in adobe masonry (AM) constructions in earthquake areas even if most of the existing constructions are not engineered, thus prone to seismic damage. Therefore, seismic retrofitting of existing AM structures is a critical issue. In this study, experimental results of diagonal compression tests on 21 adobe masonry wallets, before and after the installation of textile reinforced mortar (TRM) with either hemp or glass fibres, are presented. Hemp-TRM is found to be more effective than glass-TRM in improving the shear capacity of AM, showing a mean increase in shear strength and ductility of 25% and 260% in hemp-TRM-strengthened wallets and 12% and 100% in glass-TRM-strengthened wallets. The hemp textile allowed compatibility of the TRM to the masonry substrate, preventing premature debonding and local failure. Experimental results are compared to existing data on TRM systems made of vegetable fibres, evidencing a significant capacity enhancement through flax- and hemp-TRM systems.