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Terrestrial laser scanning (TLS) point clouds have been widely used in deformation measurement for structures. However, reliability and accuracy of resulting deformation estimation strongly depends on quality of each step of a workflow, which are not fully addressed. This study aims to give insight error of these steps, and results of the study would be guidelines for a practical community to either develop a new workflow or refine an existing one of deformation estimation based on TLS point clouds. Thus, the main contributions of the paper are investigating point cloud registration error affecting resulting deformation estimation, identifying an appropriate segmentation method used to extract data points of a deformed surface, investigating a methodology to determine an un-deformed or a reference surface for estimating deformation, and proposing a methodology to minimize the impact of outlier, noisy data and/or mixed pixels on deformation estimation.

In practice, the quality of data point clouds and of surface extraction strongly impacts on resulting deformation estimation based on laser scanning point clouds, which can cause an incorrect decision on the state of the structure if uncertainty is available. In an effort to have more comprehensive insight into those impacts, this study addresses four issues: data errors due to data registration from multiple scanning stations (Issue 1), methods used to extract point clouds of structure surfaces (Issue 2), selection of the reference surface S_ref to measure deformation (Issue 3), and available outlier and/or mixed pixels (Issue 4). This investigation demonstrates through estimating deformation of the bridge abutment, building and an oil storage tank.

The study shows that both random sample consensus (RANSAC) and region growing–based methods [a cell-based/voxel-based region growing (CRG/VRG)] can be extracted data points of surfaces, but RANSAC is only applicable for a primary primitive surface (e.g. a plane in this study) subjected to a small deformation (case study 2 and 3) and cannot eliminate mixed pixels. On another hand, CRG and VRG impose a suitable method applied for deformed, free-form surfaces. In addition, in practice, a reference surface of a structure is mostly not available. The use of a fitting plane based on a point cloud of a current surface would cause unrealistic and inaccurate deformation because outlier data points and data points of damaged areas affect an accuracy of the fitting plane. This study would recommend the use of a reference surface determined based on a design concept/specification. A smoothing method with a spatial interval can be effectively minimize, negative impact of outlier, noisy data and/or mixed pixels on deformation estimation.

Due to difficulty in logistics, an independent measurement cannot be established to assess the deformation accuracy based on TLS data point cloud in the case studies of this research. However, common laser scanners using the time-of-flight or phase-shift principle provide point clouds with accuracy in the order of 1–6 mm, while the point clouds of triangulation scanners have sub-millimetre accuracy.

This study aims to give insight error of these steps, and the results of the study would be guidelines for a practical community to either develop a new workflow or refine an existing one of deformation estimation based on TLS point clouds.

The results of this study would provide guidelines for a practical community to either develop a new workflow or refine an existing one of deformation estimation based on TLS point clouds. A low-cost method can be applied for deformation analysis of the structure.

Although a large amount of the studies used laser scanning to measure structure deformation in the last two decades, the methods mainly applied were to measure change between two states (or epochs) of the structure surface and focused on quantifying deformation-based TLS point clouds. Those studies proved that a laser scanner could be an alternative unit to acquire spatial information for deformation monitoring. However, there are still challenges in establishing an appropriate procedure to collect a high quality of point clouds and develop methods to interpret the point clouds to obtain reliable and accurate deformation, when uncertainty, including data quality and reference information, is available. Therefore, this study demonstrates the impact of data quality in a term of point cloud registration error, selected methods for extracting point clouds of surfaces, identifying reference information, and available outlier, noisy data and/or mixed pixels on deformation estimation.

The purpose of this paper is to understand if and how industrialized house building (IHB) could support productivity developments for housebuilding on project and industry levels. The take is that fragmentation of construction is one explanation for the lack of productivity growth, and that IHB could be an integrating method of overcoming horizontal and vertical fragmentation.

Singe-factor productivity measures are calculated based on data reported by IHB companies and compared to official produced and published research data. The survey covers the years 2013–2020 for IHB companies building multi-storey houses in timber. Generalization is sought through descriptive statistics by contrasting the data samples to the used means to control vertical and horizontal fragmentation formulated as three theoretical propositions.

According to the results, IHB in timber is on average more productive than conventional housebuilding at the company level, project level, in absolute and in growth terms over the eight-year period. On the company level, the labour productivity was on average 10% higher for IHB compared to general construction and positioned between general construction and general manufacturing. On the project level, IHB displayed an average cost productivity growth of 19% for an employed prefabrication degree of about 45%.

Empirical evidence is presented quantifying so far perceived advantages of IHB. By providing analysis of actual cost and project data derived from IHB companies, the article quantifies previous research that IHB is not only about prefabrication. The observed positive productivity growth in relation to the employed prefabrication degree indicates that off-site production is not a sufficient mean for reaching high productivity and productivity growth. Instead, the capabilities to integrate the operative logic of conventional housebuilding together with logic of IHB platform development and use is a probable explanation of the observed positive productivity growth.

The paper seeks to bridge the already familiar benefits of 3D printing (3DP) to the rehabilitation of cultural heritage, still based on the use of complex and expensive handcrafted techniques and scarce materials.

A compilation of different information on frequent anomalies in cultural heritage buildings and commonly used materials is conducted; subsequently, some innovative techniques used in the construction sector (3DP and 3D scanning) are addressed, as well as some case studies related to the rehabilitation of cultural heritage building elements, leading to a reflection on the opportunities and challenges of this application within these types of buildings.

The compilation of information summarised in the paper provided a clear reflection on the great potential of 3DP for cultural heritage rehabilitation, requiring the development of new mixtures (lime mortars, for example) compatible with the existing surface and, eventually, incorporating some residues that may improve interesting properties; the design of different extruders, compatible with the new mixtures developed and the articulation of 3D printers with the available mapping tools (photogrammetry and laser scanning) to reproduce the component as accurately as possible.

This paper sets the path for a new application of 3DP in construction, namely in the field of cultural heritage rehabilitation, by identifying some key opportunities, challenges and for designing the process flow associated with the different technologies involved.

The overall objective of this study is envisaged to provide decision makers with actionable insights and access to multi-risk maps for the most in-danger stave churches (SCs) among the existing 28 churches at high spatial resolution to better understand, reduce and mitigate single- and multi-risk. In addition, the present contribution aims to provide decision makers with some information to face the exacerbation of the risk caused by the expected climate change.

Material and data collection started with the consultation of the available literature related to: (1) SCs' conservation status, (2) available methodologies suitable in multi-hazard approach and (3) vulnerability leading indicators to consider when dealing with the impact of natural hazards specifically on immovable cultural heritage.

The paper contributes to a better understanding of place-based vulnerability with local mapping dimension also considering future threats posed by climate change. The results highlight the danger at which the SCs of Røldal, in case of floods, and of Ringebu, Torpo and Øye, in case of landslide, may face and stress the urgency of increasing awareness and preparedness on these potential hazards.

The contribution for the first time aims to homogeneously collect and report all together existing spread information on architectural features, conservation status and geographical attributes for the whole group of SCs by accompanying this information with as much as possible complete 2D sections collection from existing drawings and novel 3D drawn sketches created for this contribution. Then the paper contributes to a better understanding of place-based vulnerability with local mapping dimension also considering future threats posed by climate change. Then it highlights the danger of floods and landslides at which the 28 SCs are subjected. Finally it reports how these risks will change under the ongoing impact of climate change.

The purpose of this study is to analyse the crisis network response of European countries and the role played by defence organizations (DOs) during the early response phase of the pandemic, here set to encompass 75 days.

Published materials – reports, news and communications – provided by authorities and DOs were used. Some of the authors actively participated in national pandemic response networks. An exploratory approach and qualitative content analysis were applied. The data were collected in national languages from 13 European countries, and they were coded and analysed using the actors, resources and activities (ARA) framework.

This study identified three main categories of activity structures in which the DOs interacted with civilian members of response networks, health-related services, logistics services and public support services. These networks among actors were found within formal response systems and emergent networks. The DOs engaged as actors that provided a range of services when civil authorities could not cope with the huge demand for specific services and when resources were scarce in the initial response phase.

This study contributes by filling an important research gap with regard to the civil-military relations associated with the use of DO resources in the civil response to the pandemic crisis in Europe, which is described as an untraditional response. The ARA network approach provides a framework for arranging ARA and extends the wider civil-military network to expand the formal networks of the early crisis response. The study lays knowledge about the co-operation between civilian and military actors in different contexts and provides a broader understanding of the roles that DOs played in the response operations.

Is the need for stability pre-empting the need for democratic values? How can the EU cope with two contradictory security requirements: the need to promote democratic norms and to secure geostrategic interests? This paper takes on the security-democracy dilemma in a complex way that transcends the realpolitik frame overshadowing the analysis of the EU’s policy orientation in the Southern Mediterranean while considering its normative role as a fig leaf for security interests.

This paper investigates the EU’s foreign policy orientation reflected in the ENP in terms of the two logics of action of consequentialism and appropriateness. Tracing changes at the policy level over time between 2011 and 2015, the paper zooms into the implementation of the “new” ENP in the aftermath of the Arab uprisings in Egypt, Libya and Tunisia to highlight additional variation across countries.

Building on a document analysis of the official declarations for the policy-making level and of ENP action plans for the implementation level, the paper argues that local political dynamics and the level of the EU’s threat perception shape the EU’s response to the partner countries.

The purpose of this paper is to investigate two current transformation processes in the construction industry: the adoption of a novel material, cross-laminated timber (CLT), and the enhancement of digital transformation. This paper depicts the actors and interaction in the business network that is emerging around CLT construction and, in particular, how digital transformation (that is, the deployment of Construction 4.0 solutions) occurs in this business network.

Digital transformation is a relatively new phenomenon in CLT construction, and the authors, therefore, adopt a qualitative inductive research approach and rely on semi-structured interviews.

The findings of this paper suggest that it is critical for actors to adopt an interorganizational perspective in CLT construction, instead of only focusing on internal operations. An interorganizational perspective supports successful CLT construction, as well as the deployment of Construction 4.0 solutions. This will bring about the benefits of digital transformation in the construction industry.

This paper investigates the network created around CLT construction in Finland but more generally illustrates the change toward Construction 4.0 solutions.

For managers, this paper explicates the importance of networking, instead of focusing on the internal development of the company, when adopting novel solutions emerging from both construction and information technology-related advancements.

Stability and traditions are characteristic of the construction industry. New technical solutions and materials, together with calls for sustainability, have challenged the traditional ways of constructing, and for example, the development of CLT construction has led to an emergence of new business networks. This material-related process and the ongoing digital transformation of business form an interesting context for an empirical-based analysis of changing interaction and networks. This paper gives the first insights into how digital transformation can benefit the evolution of the network.

Maintaining infrastructures such as roads, bridges, railways and other civil constructions requires long term documentation that ideally should comprise a reliable reflection of the physical structures. However, the Swedish Transport Administration (TRA) states that its documentation is currently inadequate and that new working method are needed. The purpose of this paper is to study how the agency is working to improve their recordkeeping, by taking a closer look at two new positions that now coordinate the delivery of documentation from the building process teams to the agency. What is their role and what challenges do they face with regard to creating, sharing and preserving records with other areas across the TRA? The study’s purpose is also to discuss the concept of the archive in the current environment and how existing archival theory can be applied to long term documentation.

The study used a case study method, as the aim was to explore and understand recordkeeping practices and theoretical implications, without seeking to generalize the findings outside the Swedish Government. Two positions – the delivering coordinator and the receiving coordinator – were chosen as relevant focuses, due to their function as links between departments in which it was previously indicated that creating and maintaining reliable recordkeeping was difficult and where organizational structure might challenge the traditional archival theory. Documents and reports from the agency were used as research material through documentary analysis and a questionnaire consisting of 10 questions was used to conduct semi-structured interviews with 10 coordinators at the agency.

Obtaining the correct documentation at the right time and of appropriate quality from contractors and entrepreneurs was difficult, despite detailed contractual rules and regulations identifying what should be delivered. The work of the coordinators was formally connected to the important tasks of creating, sharing and preserving records with other areas within the TRA, but in reality, the coordinators faced several difficulties due to expectations of their professional role, practices in information management between different departments and archives creation at the entire agency. The interviewees therefore had differing perceptions of what was meant by TRA’s “archive”: it was variously perceived as only including the registry; comprising only the records preserved by the archives department or encompassing only those records in the registry or in the agency’s business system/s. Findings indicate that the concepts of multiple provenances and the recordkeeping “single mind” might provide insights to better inform the recordkeeping principles needed to improve the current environment.

The study was limited to the 10 interviewees in 2 roles, although there are more positions involved in handling records. Future studies may solidify or contest the different themes identified in the present paper, through interviews of those additional roles at the agency. This paper uses the Swedish concept of the archive as a point of departure in its analysis.

By increasing the knowledge about positions that are responsible for handling records at an agency, this paper can get a better understanding of how they affect the ultimate creation of archives. This will give Swedish public agencies and other organizations, better results when they are creating strategies to preserve reliable records for the future.