With concrete’s key role in construction and infrastructure, the reduction of its carbon footprint is critical for addressing global carbon emissions. One strategy to reduce environmental impact from concrete production is to replace cement clinker or fine aggregates in concrete with industrial wastes. Mine tailings, being a high-volume under-utilized resource, possess properties making it suitable for use as a partial substitute for cement or fine aggregates. This review article provides an overview of the recent findings within the topic of tailings-based concrete (TBC). Many of the identified publications aimed to describe the mechanical performance of TBC, and to optimize the concrete mix with respect to the strength and durability. The recommended cement replacement ranged from 5 to 25% and the recommended fine aggregate replacement ranged from 20 to 60%. In general, the compressive strength was decreased with increasing use of tailings as a replacement of cement. For the use of tailings as replacement for fine aggregates, the correlation was more complex, normally the mechanical performance enhanced at low replacement levels, until it reached an optimum after which it decreased. CO2 savings for replacing fine aggregate with tailings were up to 12% and for the cement replacement up to 30%. When assessing the environmental performance, most of the publications did not account for the loss of its mechanical performance, which could lead to the risk of underestimating the environmental impact. This review not only provides a basis for understanding the mechanical, toxicological, and environmental performances of TBCs, but also links the perspectives together, unveiling the connections between them. Moreover, this review presents an organized overview of the topic of TBC and points out topics for future research.

Cross-laminated timber (CLT) is one of the most sustainable, robust, and green building materials nowadays and is normally used for walls, floors, or roofs. The number of studies on CLT has increased significantly since 2010, which shows the acceptance and needs of CLT. Connection systems, rolling shear performance, and sustainability are the popular and main research topics within CLT, including wooden connections, metallic connections, adhesive and rod connections, aspect ratio, bonding performance, life cycle assessment, carbon emission, and environmental impact. Based on these three branches, the current study conducts a literature review on CLT. This review article aims to provide a valuable view and better understanding of CLT, which are linked to (1) promoting the usage of CLT and (2) summarizing the weaknesses of the CLT’s research. This article presents a full background of the CLT research and gives potential research directions for CLT as a structural material. It revealed that the design and analytical methodologies for novel timber and steel connections are the main trends. As for the CLT’s rolling shear performance, standardized testing protocol, environmental impact, and bonding quality need further development. Furthermore, the data collection, selection, and influence of different policies are important for the CLT’s sustainability assessment.

Previous research has shown a lack of studies with comparisons between primary (virgin) and secondary (re-used) building materials, and their embodied emissions. The creation of different scenarios comparing the environmental impact of virgin vs. re-used materials is also motivated by the scarcity of raw materials in the world and the emergency of mitigating greenhouse gas (GHG) emissions from buildings. The aim of this study was to investigate scenarios, including new vs. re-used building products, applying the LCA method for a wooden single-family building. The findings showed a 23% reduction potential for total released (positive) CO2e when comparing the Reference scenario with Scenario I, using re-used wooden-based materials. Further, Scenario II, using all re-used building materials except for installations, showed a 59% CO2e reduction potential compared to the Reference scenario. Finally, Scenario III, which assumes all re-used building products, showed a 92% decreased global warming potential (GWP) impact compared to the Reference scenario. However, when including biogenic carbon and benefits (A5 and D module), the Reference scenario, based on newly produced wooden building materials, has the largest negative GHG emissions. It can be concluded that the re-use of building products leads to significant carbon savings compared to using new building products.

University staff play an important role in the development of a more sustainable world. Their attitudes towards pro-environmental behavior and environmental values likely have an influence on ethics, the current society and future generations. Therefore, this study aims to measure and interpret the ecological worldview among university staff using the validated New Environmental Paradigm (NEP) survey. The mean NEP-score was 3.68. This overall value is of the same magnitude as many samples from diverse geographical areas with representatives and students, but it is considerably lower than for environmentalists. The facet Balance of nature reported the highest score whereas Limits to growth the lowest score. Women had higher mean score, mainly explained by the higher score in the facet Human domination over nature. There is a potential for improving the ecological world-view scores of University staff, who are an unstudied and important group. Values in higher education may influence sustainable development, environmental ethics and society.

As a sustainable construction material, timber is more promoted than steel, concrete, and aluminum nowadays. The building industry benefits from using timber based on several perspectives, including decarbonization, improved energy efficiency, and easier recycling and disposal processes. The cross-laminated timber (CLT) panel is one of the widely utilized engineered wood products in construction for floors, which is an ideal alternative option for replacing reinforced concrete. One single CLT panel has an outstanding flexural behavior. However, CLT cannot be extended independently without external connections, which are normally made of steel. This article proposes two innovative adhesive-free edge connections made of timber, the double surface (DS) and half-lapped (HL) connections. These connections were designed to connect two CLT panels along their weak direction. Parametric studies consisting of twenty models were conducted on the proposed edge connections to investigate the effects of different factors and the flexural behavior of CLT panels with these edge connections under a four-point bending test. Numerical simulations of all the models were done in the current study by using ABAQUS 2022. Furthermore, the employed material properties and other relevant inputs (VUSDFLD subroutines, time steps, meshes, etc.) of the numerical models were validated through existing experiments. The results demonstrated that the maximum and minimum load capacities among the studied models were 6.23 kN and 0.35 kN, respectively. The load–displacement responses, strain, stress, and defection distributions were collected and analyzed, as well as their failure modes. It was revealed that the CLT panels’ load capacity was distinctly improved due to the increment of the connectors’ number (55.05%) and horizontal length (80.81%), which also reinforced the stability. Based on the findings, it was indicated that adhesive-free timber connections could be used for CLT panels in buildings and replace traditional construction materials, having profound potential for improving buildings’ sustainability and energy efficiency.

This study adapted the mean age of air, a time scale widely utilized in evaluating indoor ventilation, to assess the impact of building layouts on urban ventilation capacity. To distinguish it from its applications in enclosed indoor environments, the adapted index was termed the effective mean age of air (T_E). Based on an experimentally validated method, computational fluid dynamic (CFD) simulations were performed for parametric studies on four generic parameters that describe urban morphologies, including building height, building density, and variations in the heights or frontal areas of adjacent buildings. At the breathing level (z = 1.7 m), the results indicated three distinct distribution patterns of insufficiently ventilated areas: within recirculation zones behind buildings, in the downstream sections of the main road, or within recirculation zones near lateral facades. The spatial heterogeneity of ventilation capacity was emphasized through the statistical distributions of T_E. In most cases, convective transport dominates the purging process for the whole canopy zone, while turbulent transport prevails for the pedestrian zone. Additionally, comparisons with a reference case simulating an open area highlighted the dual effects of buildings on urban ventilation, notably through the enhanced dilution promoted by the helical flows between buildings. This study also serves as a preliminary CFD practice utilizing T_E with the homogenous emission method, and demonstrates its capability for assessing urban ventilation potential in urban planning.

Timber, a renewable resource with a low carbon footprint, has a giant potential to replace reinforced concrete (RC) structures in housing, which can decrease the environmental impact and lead to a healthier construction work environment. However, connections, as part of timber frames, are majorly made of steel and adhesives, which emit harmful pollution and negatively impact the timber structures. This study focuses on enhancing sustainability in construction by proposing adhesive-free timber connections for glued-laminated timber (glulam) panels. The study aims to contribute toward sustainable construction practices by reducing the reliance on adhesives and exploring alternative connection methods for glulam panels. This article presents four-point out-of-plane bending tests on glulam panels with innovative adhesive-free timber connections. The studied specimens compromised fabricated glulam panels and densified wood connectors made of pine and beech, respectively. Six different adhesive-free wood connections were designed and applied independently. Each connection was connected to two glulam panels by their end-grain sides. Therefore, twelve glulam panels, connected using these six connections, were tested. The panels had identical dimensions and materials. The connections were applied at the mid-span of the two connected panels. The experimental results on the flexural behavior, ultimate load, strength, and displacement of the six specimens are presented. The obtained mean load-carrying capacity of the specimens in the current research was greatly higher than that of the other specimens with different timber connections, such as timber-timber connections using compressed wood connectors. Additionally, the failure modes of the specimens were analyzed, which mostly exhibited the shear failure and delamination behavior. Most of the tested specimens failed in a ductile manner with a high ductility, which is suitable for the earthquake regions. The findings demonstrated the potential of using adhesive-free timber connections in glulam panels and contributing to the development of zero-energy buildings and sustainable construction practices while maintaining the structural integrity.

The use of timber as a building material is becoming increasingly popular thanks to its superior environmental performance compared with concrete and steel. However, timber structures rely on solid connections to improve their weak expansibility. Steel connections can be prone to corrosion over time, leading to the decreased structural integrity. Additionally, steel connections require more material and energy to manufacture and install compared with timber connections. This article focuses on the flexural performance of cross-laminated timber (CLT) panels with adhesive-free edge connections under four-point bending tests. First, numerical models of experimentally tested CLT panels were constructed using the finite element (FE) software ABAQUS. Then, these FE models were validated with the comparisons of their results with those of the experimental tests. Afterward, four new adhesive-free edge connections using timber for the CLT panels were developed in this study, helping sustainable construction. Utilizing the designed edge connections of the current study, forty-one parametric studies were numerically conducted on the connected CLT panels to investigate their ultimate loads, strains, displacements, moment capacities, failure modes, and effective stiffness. The factors affecting the edge connections’ load-bearing capacity were also examined and discussed. The study provides helpful insights into the development of CLT as a sustainable construction material with improved adhesive-free edge connections.

There is a need for new tools in urban planning, design, and management (urban PDM) of green-blue infrastructure (GBI) to better support resilience and sustainable development. Virtual Reality (VR) emerges as a potential tool in this context. GBI provides a diversity of ecosystem services that increase the capacity of urban environments to absorb change while continuing to develop (adaptive capacity), a key factor in resilience and sustainability. However, there is a lack of tools capable of effectively capturing and communicating the designs, functions, and uses of GBI. Despite this need, research on the contributions of VR as a tool in urban PDM of GBI remains limited. To address this gap, an exploratory experiment using inductive qualitative data analysis was conducted. Participants of different ages and with different expertise viewed 360-degree video clips from urban areas through VR, completed a questionnaire, and participated in interviews. The results showed that the 360-degree video VR experience enhanced participants’ understanding of the viewed sites. Specifically, participants paid attention to details, captured the context, responded by generating emotional engagement, identified site development potential, and described an immersive experience. These results align with key principles for the sustainable management of ecosystem services, such as participation, learning, diversity, place-making, and stewardship; and adaptive capacity aspects such as processes and results grounded in complexity-embracing creativity. Our analysis shows that 360-degree video VR can increase the understanding of complexities, connections, and nuances in the urban environment. We conclude that 360-degree video VR could serve as a valuable complement to traditional tools in urban PDM, enriching decision-making with information that can support adaptive capacity, resilience, and sustainability.

This study explored first-line managers’ leadership behavior profiles regarding their goals for utilizing the garden at residential care facilities for older people. Semi-structured interviews were conducted with a convenience sample of first-line managers (n = 12) in Sweden. Data were analyzed using deductive content analysis theoretically guided by the Three-dimensional Leadership Model. The results showed that the main leadership behavior profiles were related to the dimensions structure, relation and change. The managers emphasized workplace regulations and goals. They allowed staff to make decisions and encouraged them to see problems and opportunities.