Building Research Institute

Evaluation equations for ultimate shear capacity and allowable shear strength of SFRC shear walls were proposed, and their validity was examined using the results of previous experiments and analysis. It was confirmed that the experimental maximum shear capacity could be evaluated accurately and on the safe side by using an equation that accumulates the shear strength that steel fibers can bear to the shear capacity equation (truss-arch mechanism) for RC shear walls. In addition, it was confirmed that the experimental maximum capacity could be simulated using a finite element analysis model that simplified the SFRC material properties.

Urban surfaces such as Facades and rooftops are critical mediators of microclimatic conditions in cities, influencing the thermal comfort of both human and non-human inhabitants. Within a more-than-human design perspective, these surfaces may be understood as interfaces where microclimatic regulation can support ecologically relevant funtions, including nesting habitats that moderate microclimatic extremes for wild bee species in dense urban environments. This study builds on prior research into additive-manufactured (3D-printed) porous cellular geometries—specifically Triply Periodic Minimal Surfaces (TPMS) and Adaptive Density Minimal Surfaces (ADMS)—developed as structural envelopes for nesting tubes intended to mitigate heat peaks experienced by cavity-nesting wild bees under urban heat island (UHI) conditions. These species experience metabolic stress when internal cavity temperatures (T nest ) exceed 35 °C and face lethal risks above 40 °C. Previous experiments showed that such geometries can attenuate internal temperature fluctuations by up to 1.6 K compared with conventional materials, although passive geometric performance alone proved insufficient during extreme summer conditions. To enhance thermal regulation, a bio-inspired evaporative-cooling strategy was developed, modelled after the droplet collection and retention behaviour of Apis mellifera . Here, the honeybee is used solely as a biological analogue for water-management mechanisms, rather than as the species under investigation. Comparative field tests in Stuttgart, Germany, evaluated small-scale water-supplied (sWS) and control (sC) samples alongside traditional nesting materials. There resultsinformed the design of full-scale Facade panels—a water-supplied (pWS) and a control (pC) variant—later tested in a climatic chamber simulating heatwave conditions. Across experiments, pWS achieved mean temperature differentials (ΔT) of 8.6–10.2 K relative to pC, indicating the technical potential of evaporative cooling to reduce microclimate thermal stress in biologically sensitive cavities and to inform climate-responsive architectural surface design.

The present experimental study aims to analyze the behavior of multistory cross-laminated timber (CLT) shear walls with cut openings, considering realistic configurations commonly encountered in CLT buildings. In addition, this study investigates the influence of floor elements on CLT shear wall performance. Experimental results demonstrated a 40% increase in load-bearing capacity compared with floorless configurations, attributed to floor-induced lintel beam stiffening that promotes near-rigid behavior and fastener mobilization. Quantitative improvements included 36% greater ultimate ductility, 8% enhanced system ductility, and 30% increased energy-dissipation capacity through floor–wall friction. Findings revealed that conventional segmented analysis methods significantly underestimate walls with cutout-produced lintels. Two-story specimens exhibited consistent triangular displacement distribution across all loading phases, with equivalent interstory ductility confirming deformation dominated by base rotation, aligning with seismic rocking principles. Floor integration eliminated base compression, increasing rotational capacity while engaging ground-level bolts. Second-story behavior transitioned to single-center-of-rotation kinematics, indicating enhanced stability. The floor’s restraint effect reduced lintel cracking while promoting controlled bolt failure, concentrating damage in replaceable connections and demonstrating high system reparability.

Abstract In response to the durability and mechanization requirements of substation building structures in the coastal areas of Fujian Province, this paper proposes a new prefabricated concrete structural system suitable for these regions. The key design aspects are summarized, and the system is applied in a 110 kV substation project. Finally, a benefit comparison is made with traditional cast-in-place reinforced concrete and steel structure solutions. The study shows that, firstly, the new prefabricated concrete structural system enables “full above-ground and underground assembly” in substation projects, eliminating the need for on-site supports and formwork, thereby enhancing construction mechanization and automation. Secondly, the overall cost of the new prefabricated concrete structure is comparable to that of traditional cast-in-place reinforced concrete but lower than that of steel structures. It also offers superior fire resistance, durability, and impermeability compared to steel. Thirdly, during the construction phase of substation projects, the new prefabricated concrete structure achieves an 11.37% reduction in carbon emissions compared to traditional cast-in-place reinforced concrete and a 26.54% reduction compared to steel structures in terms of building materials. The findings provide a technical solution for promoting the application of prefabricated concrete structures in substation projects.

Purpose This study aims to explore stakeholder communication strategies for facilitating the adoption of circular economy (CE) practices in the Nigerian construction industry. It addresses a critical gap in the existing literature by focusing on communication dynamics within a developing economy, where sociocultural and infrastructural challenges significantly influence the adoption of CE. Design/methodology/approach A qualitative research approach was employed, using a purposive sampling technique to select 25 stakeholders across 3 major groups: industry professionals, government officials and academics. Semi-structured interviews were conducted, and data were analysed thematically to identify key communication strategies for fostering stakeholder collaboration and overcoming communication barriers in promoting CE in the Nigerian construction industry. Findings Five core themes emerged from the analysis: participatory approaches, formalised communication channels, integration of digital tools, capacity building and awareness creation and the role of policy and governance. The findings highlight that context-specific communication strategies are critical for aligning stakeholder interests, promoting trust and fostering CE adoption in resource-constrained environments. Research limitations/implications The study was geographically limited to North Central Nigeria, and the findings may not be generalisable to other regions with differing socioeconomic conditions. Future research could adopt mixed-methods approaches and expand the geographic scope to provide a more comprehensive understanding of stakeholder communication in CE adoption. Originality/value This study contributes to the knowledge of CE adoption by providing context-specific insights into stakeholder communication in a developing economy. It offers a novel framework for addressing communication barriers and fostering collaboration in resource-constrained environments.

This study extends previous work that utilizes a learnable resizer (LR) integrated into deep learning models for segmenting sparse point cloud-derived imagery, which often suffers from poor feature representation. While prior research demonstrated the potential of LRs to enhance segmentation performance, this study evaluates their effectiveness for segmenting small and sparse features in typical scenarios where prior information is unavailable for masking. The analysis reveals that, although the LR significantly increases recall, it does not consistently or significantly improve precision. This discrepancy is attributed to the LR’s behavior, which causes target road marking features to appear as consolidated regions rather than discrete dots, leading to misclassifications in areas lacking point cloud values. Furthermore, this study also extends the ablation study regarding the impact of different resizing operations and LR placements, demonstrating that, contrary to previous work, using LR in both downsampling and upsampling phases yields better performance. Despite these challenges, the findings suggest that LRs remain valuable in retaining critical features. The study proposes that further refinement of the LR, with a focus on controlling overfitting, could improve precision while maintaining recall benefits, ultimately enhancing segmentation performance for small and sparse target features.

人口減少下における水・衛生インフラを今後どのように維持管理していくのかという問題は，すでにわが国にとって喫緊の課題となっている。特に，運営効率向上だけでは根本的な解決が難しいような，低人口密度地域の水・衛生インフラに対して，現実的な解決策の選択肢を示すことが求められている。本稿では，わが国においてまだ情報の少ない分散型や地域自律管理型のしくみについて，主に北海道における小規模水供給システムの実例を参照しながら，低人口密度地域における人口減少への適応策としての可能性と課題について整理する。また，すでに浄化槽による分散型のしくみが普及しているわが国の小規模衛生インフラの今後についても，人口減少下での資源循環という視点からその課題と可能性について整理する。

ABSTRACTThe inclusion of sidewalls is a typical architectural feature in building façades, which has raised significant concerns about their potential to accelerate flame spread, particularly with the increasing prevalence of high‐rise buildings. This paper presents an experimental investigation and analysis of façade flame with a single sidewall. Experiments were conducted by employing a large‐scale façade calibration test, following the standard of JIS A 1310 with additional sidewall configurations. The distance between a sidewall and a façade opening was parametrically changed. A propane burner located at the rear center of the combustion chamber provides a quasi‐steady heat release rate (HRR) ranging from 600 to 900 kW. It is found that the flame height is more affected by sidewall distances when the HRR is sufficiently larger than the outflow HRR. Combined with flame and façade temperatures, a sidewall distance of 0.2 m is considered crucial for the performance of fire loads in the case of sidewall façades with square openings. The temperature of the flame trajectory is characterized by the neutral plane (NP)‐adapted Yokoi model, with improved convergence under varied HRRs and sidewall distances.