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The construction sector contributes significantly to climate change and energy consumption. The decarbonization can be facilitated when energy- and resource- intensive materials such as concrete is broadly replaced with renewable materials such as timber. An extensiveutilisation of timber in structures demands carefully defined and compulsory applied design rules that maximize the value of the natural resource under consideration of environmental impacts. This largely exceeds the scope of the decision rules in current structural design codes, which have been conceived with the primary objective of sufficient safety. The paper stresses the usefulness of risk-informed optimization approaches for enhancing the decision scope of these rules with consideration of the environmental performance of structures. Taking widely implemented life cycle assessment approaches as a basis, it is discussed how existing optimization frameworks could be modified to this end, with emphasis on the global warming potential of timber structures.

Interlocking Particle Structures (IPS) are geometrically stable assemblies, usually fabricated from plate type elements that are interconnected by slotted joints. IPS are demountable and their components have the potential to be used and reused in different structures and configurations. This paper explores the applicability of birch plywood panels, which are characterized by a high surface hardness, for this type of structural system. Experimental tests were conducted to determine the mechanical properties of birch plywood plates. Moreover, IPS connections with different geometrical properties were investigated for two different load exposures: bending and rotation. The characteristics under bending exposure are influenced by the orientation of the face-veneers. For the rotational load exposure, very small strength and stiffness properties have been identified. A linear elastic finite element model is presented that shows a wide agreement with the test results. The study serves as an initial probe into the performance of IPS structures at the component level. Various aspects that are relevant for the design of IPS, such as the assembly, the accuracy and challenges regarding digital fabrication, the durability, and the structural performance are discussed.

Matlab

The aim of this paper is to highlight some drawbacks and uncertainties related to possible imperfections associated with the use of key European and American standard test methods on shear strength measurement of wood adhesive bonds. For this purpose, a brief introduction is provided on adhesive bonding of wood materials and relevant failure modes under shear stress. Two standardized test methods for measuring the shear strength of wood adhesives are introduced, followed by a discussion around the drawbacks and imperfections related to the practical application of the two test methods. Finally, the research needs in this area are highlighted and some recommendations are made for addressing them in the future studies. Non

The application of deconstructable connectors in timber-concrete composite (TCC) floors enables the possibility of disassembly and reuse of timber materials at the end of building’s life. This paper introduces the initial concept of a deconstructable TCC connector comprised of a self-tapping screw embedded in a plug made of rigid polyvinyl chloride and a level adjuster made of silicone rubber. This connection system is versatile and can be applied for prefabrication and in-situ concrete casting of TCC floors in both wet-dry and dry-dry systems. The paper presents the results of preliminary tests on the shear performance of four different configurations of the connector system in T-section glulam-concrete composites. The shear performance is compared to that of a permanent connector made with the same type of self-tapping screw. The failure modes observed are also analyzed to provide technical information for further optimization of the connector in the future. Non

ChemistryOpen : including thesis treasury 8(7), 951-960 (2019). doi:10.1002/open.201900203, Published by Wiley-VCH-Verl., Weinheim

Connections are important details in timber construction, connecting single members and elements to larger structures. The design of connections is regulated by structural standards that in general make use of the so called semi-probabilistic safety concept. This concept contains reliability elements, i.e. a conventional deterministic representation of strength and stiffness related properties and action effects as specified fractile values of the underlying probability distributions, partial factors and load combination factors. Standardisation bodies ascertain the reliability elements in order to provide sufficient reliability for the design solutions that result from the application of the code. This is also done for the semi-probabilistic design basis for timber connections. However, despite of the fundamental differences in mechanical and material behaviour, in general the same reliability elements as for the design of timber structural components are used. The present article takes a critical appraisal of the existing safety format for timber connections as implemented in the Eurocode., Proceedings of the Conference of COST Action FP1402, ISBN:978-3-85125-553-9, ISBN:978-3-85125-554-6

Environmental performance of timber bridges during their lifespan has become important in recent years. In this study, two timber design alternatives of the Driva Bridge located in Norway were investigated and compared. The study applied Life Cycle Assessment (LCA) for addressing (1) the distribution of total environmental impact and energy consumption, and (2) the environmental impact and energy consumption variations due to different End-of-Life (EoL) scenarios for timber material. The results relied on five selected midpoint environmental impact indicators. It indicates that different EoL scenarios of timber can largely affect the total environmental impact, and the quantity of steel used significantly influence the total environmental impact as well as total energy consumption.

INTER Proceedings, 49, ISSN:2199-9740, International Network on Timber Engineering Research: Proceedings of Meeting 49

Glued laminated timber (GLT) is a structural product composed of several layers of timber boards glued together. GLT components have many advantages, such as the larger range of available component dimensions to choose from, the environmental sustainability or the e- cient ratio between weight and load-bearing capacity. Because of that, GLT beams have been established as one of the most important products in timber engineering in the last decades. As a natural grown material, timber properties exhibit higher variability, compared with other building materials. The variability is pronounced not only between dierent structural elements but also within single elements, the latter being highly related to the occurrence of knot clusters. Due to the highly inhomogeneous structure of timber, the prediction of the material properties of GLT beams is aected by large uncertainties. In the presented thesis, the in uence of varying material properties on the load-bearing capacity of GLT beams was investigated. Thus the thesis contributes to develop the quality of GLT beams, in terms of reliability and eciency. Detailed, non-destructive investigations of altogether 400 timber boards were performed. Thereby, dierent strength and stiness related indicators, such as the position and characteristic of knots, or the eigenfrequency, were assessed. Furthermore, non-destructive tensile test were performed to estimate the stiness properties of knot clusters. Out of the investigated timber boards, GLT beams having a precisely-known beam setup were fabricated. As a result, the exact position of each particular timber board (and each particular knot cluster) within the GLT beams was known. Afterwards, bending tests were performed to estimate the load-bearing capacity of these GLT beams. Thereby, the in uence of knot clusters and nger joint connections on the deformation and failure behaviour was investigated. In addition to the experimental investigations, a probabilistic approach for modelling GLT beams (referred to as GLT model ) was developed. Thereby, at rst, timber boards are simulated according to their natural growth characteristics. Afterwards, out of the simulated timber boards, virtual GLT beams are fabricated. Finally, the load-bearing behaviour of these GLT beams is estimated by using a numerical model. To assure the quality of the numerical model, it was validated with the test results. Using the GLT model, the in uence of dierent parameters, such as the position and characteristics of knots, or the quality of nger joint connections, on the load-bearing capacity of GLT beams was investigated. One further goal of this thesis was the investigation of machine-grading indicators, that are measured during the grading process. Therefore, all the investigations presented in this thesis are conducted for indicators measured in laboratory and machine-grading indicators. The same applies for the GLT model, which was also developed for both types of indicators., IBK Bericht, 360

IBK Bericht, 350

This special issue on brokering knowledge and corporate culture covers the relationships between culture and knowledge as concepts or areas of reality that are closely linked to company practice and management literature. As regards knowledge, all forms of our action upon reality (know how, technology, organisational routines and differing practices) or of our understanding of the world (systematic organisation of ideas and concepts) are forms of knowledge; and all the ways in which physical, technical or social reality manifests itself as a consequence of nature or human action, are the supports on which knowledge is founded (Akehurst et al., 2011, pp.183 184). These supports explain basic aspects of knowledge creation and its transfer or dissemination (brokering knowledge). In an analysis of knowledge with reference to the creation of knowledge through interaction between tacit and explicit knowledge Nonaka and Takeuchi (1995) and Crossan et al. (1999) refer to individual members of the organisation, groups and the organisation as a whole as the ontological supports of knowledge; and in a broader vision, where knowledge creation stems from experience and practice in different areas of reality, the ontological basis or support for knowledge lies in the physical, technical and social dimensions of that reality

International audience

IBK Bericht, 339

This report describes the aim, scope, underlying literature and results of the research project "The Nexus between the Financial and the Real Sector". We studied the contribution of the financial sector as a whole and its individual segments (bank credits, the issuance of bonds and shares) to real economic growth in EU Member and Candidate Countries, the United States and Japan. We supplement existing approaches with the inclusion of the bond market and of foreign direct investment in the banking sector, wherein for the first time, we provide empirical evidence for slightly positive effects thereof. Methodically, we extend previous research by the production-function approach and document the importance of the market microstructure. We recommend to include liberalisation and integration effects, the bond and insurance sector, and effects of foreign bank entry and investment into future research on the Finance-Growth-Nexus. (author's abstract), Series: EI Working Papers / Europainstitut

We use annual real GDP and the volume of the bond, stock and credit markets to assess the causal relationship between the aggregate bond market development and economic growth in the USA, Japan, Germany, Great Britain, Italy, France and the Netherlands over the 1950 to 2001 period. The literature on the real - financial nexus to date has focused on the credit and stock markets, with few exceptions. Partially due to data availability problems, the impact of bond markets on economic growth has not yet been examined in the same way. To fill this gap we provide empirical evidence for long-run equilibrium and Granger causality in at least one direction in the relationship among real GDP and bond, credit and stock markets in seven economies with large bond markets. The supplyleading hypothesis that development of the financial markets enhances growth is supported in all countries except for Germany. The demand-leading hypothesis that economic development pulls the development of the financial markets is supported only for Germany. A feedback between domestic credits and output is found in Japan. There is evidence for a feedback between the equity markets and real output in Japan and the Netherlands. (author's abstract), Series: EI Working Papers / Europainstitut

The proposed method enables us to identify cultural standards, i.e. the underlying norms of thinking, sensing, perceiving, judging, and acting that the vast majority of individuals in a given culture is considering as normal for themselves and others. Norms of behaviour can be different across societies even if the underlying values are the same and can cause critical incidents to emerge. A sequence of methodological steps allows systematically dealing with sampling, interviewer, interpretation, construct, and culture bias in cross-cultural qualitative research based on narrative interviews.(author's abstract), Series: EI Working Papers / Europainstitut

This paper examines for the first time the relationship between the net issue values of aggregate bonds, as well as the different bond sectors separately, and economic growth. The other new feature of this study is the usage of quarterly data. Granger causalities are calculated for time series of 15 European countries, the USA, and Japan in order to test if there is a positive relationship between the development of bond markets and economic growth also for shorter time periods. The significant Granger causalities found show the following tendency: Economic growth is causal for net issue values of government bonds, and net issuance of corporate and financial institutions bonds are causal for economic growth. That finding is important for the future architecture of the financial sector, in particular in emerging markets and the new EU member countries. (author's abstract), Series: EI Working Papers / Europainstitut