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To maximize the amount of carbon-sequestering mass timber and demonstrate the potential for mass timber across a range of building types and scales, DIALOG and EllisDon have developed a hybrid timber floor system (HTFS) that is composed of post-tensioned (PT) concrete beams, cross laminated timber (CLT) panels, and concrete topping connected to each other through self-tapping screws and kerf plates. This paper presents the fire performance of this novel HTFS through a combination of testing and modeling. Two mid-span sectional specimens of HTFS without concrete topping were exposed to the standard fire of CAN/ULC S101. The char depth and char rate of CLT were measured, and the temperature at specific locations were recorded to verify the design and the developed advanced finite element models. Advanced 2D models were developed to investigate the influence of steel properties and the effect from concrete spalling, and the modeling approach adopted in the refined 3D model. The developed models can estimate the char depth with difference less than 5%, and the temperature in reinforcing bars, PT duct, and concrete comparable to the average of the test results. The experimental and simulation results give an insight into the fire performance of this novel HTFS. [ABSTRACT FROM AUTHOR]

As one of the main forms of traditional timber buildings, the column-and-tie timber (Chuan-Dou style) structure is still widely used in South China. Compared to global behavior of those structures, less attention was paid to the vibrational performance of the wood floor systems in the structures. In this study, both traditional wood floor systems and nailed cross-laminated timber (NCLT) floor systems were tested in a full-scale column-and-tie structure. The vibrational properties of the two floor systems, including the fundamental frequency, the deflections at static point load root-mean-square amplitude, were obtained and compared. It was found that in terms of the fundamental frequency and the deflections at static point load, both floors meet the suggested requirements. In the sense of root-mean-square amplitudes, the vibrational performance of both floors is not satisfying. The vibrational performance of the NCLT floor is better than that of the traditional floor, and the vibrational performance of the NCLT floor may be improved further by increasing the number of nails between laminations and changing the boundary conditions in the subsequent study, which is only our speculation, and the real situation needs to be further investigated. This research helps to understand the vibrational performance of traditional wood floors and provides a possible floor system with better vibration serviceability in column-and-tie timber structures. [ABSTRACT FROM AUTHOR]

Mass timber panels including cross-laminated timber (CLT), dowel-laminated timber (DLT), and nail-laminated timber (NLT) are used increasingly as floor slabs in mass timber buildings and hybrid timber buildings. The sound insulation performance of bare mass timber structural floors is insufficient due to their lightweight and relatively high bending stiffness. Floating concrete toppings are commonly applied for improved sound insulation performance with an elastic interlayer. The effect of different elastic interlayers and thickness of concrete toppings on improving the impact sound insulation performance was investigated experimentally according to ASTM standards in this study. The results showed that with the same elastic layer, thicker concrete toppings resulted in better impact sound insulation performance with a higher apparent impact insulation class (AIIC). However, by increasing the concrete thickness from 38 to 50 mm and to 70 mm, the improvement of AIIC between two thicknesses was only within 3, and a significant improvement up to 9 was observed with a 100-mm-thick concrete topping. In general, elastic interlayers with lower dynamic stiffness values performed better; however, the performance was product dependent though the apparent dynamic stiffness was measured using the same standard method. Moreover, with the same panel thickness and wood species, a bare DLT floor provided higher AIIC (35) than a bare CLT (21), but each mass timber floor with the same interlayer and floating concrete topping had the same impact sound attenuation performance. The ISO empirical prediction equation overestimated the impact sound attenuation of floating concrete toppings on mass timber floors. [ABSTRACT FROM AUTHOR]

During the excavations carried out in the İnönü Cave, located within the Western Black Sea region of Türkiye, four separate floor structures made of wood, dating back to the Late Bronze Age (1436-1123 Cal BCE), were unearthed. The way the corners of the structures are connected shows that the structures were built with the çantı or bell technique, a traditional nail-less wooden architectural form of the Black Sea region. Thanks to the wet and stable environmental conditions within the cave, the wooden floors have survived and are well preserved from the Late Bronze Age to the present day. This study presents the details of the conservation practices developed and deployed in order to ensure that the wooden floors are well protected and remain available for study in the short and medium term. [ABSTRACT FROM AUTHOR]

Abuse of the highly toxic compound fentanyl and its analogues is increasing, raising serious public health concerns due to their potency and availability. Therefore, there is a need for decontamination methodologies to safely remove fentanyl to avoid harmful exposure. In this study, the efficacy of commercial and in-house synthesized decontamination agents (Dahlgren Decon, RSDL (Reactive Skin Decontamination Lotion), FAST-ACT (First applied sorbent treatment against chemical threats), GDS2000, alldecont MED, bleach, Domestos Spray Bleach, Effekt Klor, MgO, TiO2-nanodiamond, and CeO2) were evaluated for the degradation of fentanyl and carfentanil under controlled laboratory conditions and on wooden floor surfaces. Liquid chromatography/mass spectrometry analysis showed that oxidative decontamination agents were the most effective, with N-oxides identified as major degradation products. The physiological effects of these N-oxides were also investigated regarding their ability to activate the µ-opioid receptor and their metabolism in human liver microsomes. The results provide empirical evidence that complements prior research findings on the degradation of fentanyl and carfentanil using a variety of decontamination agents. [ABSTRACT FROM AUTHOR]

This paper presents numerical simulations within the frame of the project SERA—AIMS (Seismic Testing of Adjacent Interacting Masonry Structures). The study includes blind pre-diction and post-diction stages. The former was developed before performing the shaking table tests at the laboratory facilities of LNEC (Lisbon), while the latter was carried out once the test results were known. For both, three-dimensional finite element models were prepared following a macro-modelling approach. The structure consisted of a half-scaled masonry aggregate composed by two units with different floor levels. Material properties used for the pre-diction model were based on preliminary tests previously provided to the participants. The masonry constitutive model used for the pre-diction study reproduced classical stress–strain envelope, whereas a more refined model was adopted for the post-diction. After eigenvalue analysis, incremental nonlinear time history analysis was performed under a unique sequence based on the given load protocol to account for damage accumulation. In the post-diction, the numerical model was calibrated on the data recorded during the shaking table tests and nonlinear dynamic analysis repeated under the recorded accelerogram sequence. The interaction between the two units was simulated through interface elements. Moreover, the timber floors were accounted following different strategies: not modelling or considering nonlinear wall-to-floor connections. Advantages and disadvantages are then analysed, comparing the pre-diction and post-diction results with the experimental data. Numerical results differ from the experimental outcomes regarding displacements and interface pounding, although a clear improvement is visible in the post-diction model. [ABSTRACT FROM AUTHOR]

The article discusses a performance titled "meetinghouse" by Miriam Cantor-Stone and Brece Honeycutt at the Shaker Heritage Society in Albany, New York, blending spoken word with Shaker hymns. It commemorates the 250th anniversary of Arrival Day for the Shakers, founded by Mother Ann Lee. The piece explores themes of labor, nature, and collaboration, linking the Shakers to Thomas Merton and Emily Dickinson. The performance highlights the sacred space of the Shakers and their unique beliefs in pacifism, communal living, and equality. [Extracted from the article]

Structural mass timber has been used more often in buildings over the last 5 years, given its potential to be a sustainable alternative. However, concerns still exist around the fire safety of mass timber structures, and current mass timber building designers must consider a variety of fire protection strategies, including but not limited to noncombustible protection and design for sacrificial char thickness. This research focuses on better understanding how prescriptive code fire protection strategies affect the sustainability goals that have partially driven mass timber use. This paper studies how decisions during early design can reduce embodied carbon (EC), the initial energy use of a structure's construction. Five structural floor system types were modeled parametrically for various levels of fire protection. System types included timber–concrete composites, cross-laminated timber (CLT)–steel hybrids, and all-timber systems. The resulting EC data analysis reveals that all-timber systems perform the best for EC when the fully protected option is used at shorter spans, when the combined approach option is used at midrange spans, and when the fully exposed timber option is used at longer spans. Across all studied systems, the shallowest possible depth occurred for the 10-ft (3.05-m) spanning CLT–steel hybrid systems at 11.5 in. (292 mm) deep for the fully protected system, and the lowest possible EC was 10.5 lb CO2 eq/ft2 (51.3 kg CO2 eq/m2) for the fully protected 10-ft (3.05 m) all-timber system. [ABSTRACT FROM AUTHOR]

The article explores the author's reflections on the roles of leading and following, drawing parallels between ballroom dancing and spiritual guidance. Through personal experiences as a ballroom dancer and insights from John Henry Newman's writings, the author contemplates the challenges of relinquishing control and trusting in divine direction. The author grapples with the complexities of obedience, pride, doubt, and faith, ultimately seeking clarity and guidance in navigating the spiritual journey. The metaphor of dancing with a partner is used to illustrate the nuanced and unique nature of following divine guidance, acknowledging the limitations of human understanding in comprehending the vastness of God. [Extracted from the article]

In this study, the structural performance of a new type of lightweight composite cold-formed steel and timber (CFST) flooring system has been investigated by conducting four-point bending tests on 13 specimens. A bare cold-formed steel system without timber sheathing was also tested to provide a benchmark response to which the strength and stiffness of the composite system were compared. This paper presents key findings on the flooring system's structural behavior and performance parameters, such as ultimate bending capacity, load-deflection response, load-slip response, and failure modes, by categorizing 13 specimens into four subgroups based on shear connector types and spacings. In the proposed composite CFST flooring system, 45-mm thick structural plywood panels were connected to the 2.4-mm thick cold-formed steel C-section joist using self-drilling screws, coach screws, and nuts and bolts. The performance of different types of shear connectors on the composite action is experimentally investigated and compared with the theoretical plastic section. Furthermore, the load-carrying capacity, effective bending stiffness, and deflection of composite CFST beams were computed theoretically using elastic theory and compared to experimental results, which showed good agreement. [ABSTRACT FROM AUTHOR]

The use of wood in the construction sector to reduce greenhouse gas (GHG) emissions is garnering global interest. In South Korea, the wood usage in public buildings is limited, being influenced by factors such as the high price of wood products and their limited use in large structures. In this work the future wood consumption in South Korea is predicted based on its potential use in current public buildings. The structural wood products required for the buildings were quantified based on the available statistical data. Items investigated were the (1) number of buildings started, (2) ratio of public buildings, (3) ratio of wooden structures, (4) average floor area of wooden buildings, (5) material cost per floor, and (6) wood prices. Assuming that the buildings contain reinforced-concrete and wooden structures, the wood consumption was estimated based on the replacement ratio. The results indicated that the prices of wood products were relatively higher than those of raw timber. The number of buildings is expected to decrease in line with the expected population decline, resulting in the decrease of wood amount required for public buildings. To achieve long-term GHG-reduction goals, it is important to replace the existing public buildings in Korea with wooden structures. [ABSTRACT FROM AUTHOR]

Quantitative analysis of human gait is critical for the early discovery, progressive tracking, and rehabilitation of neurological and musculoskeletal disorders, such as Parkinson's disease, stroke, and cerebral palsy. Gait analysis typically involves estimating gait characteristics, such as spatiotemporal gait parameters and gait health indicators (e.g., step time, length, symmetry, and balance). Traditional methods of gait analysis involve the use of cameras, wearables, and force plates but are limited in operational requirements when applied in daily life, such as direct line-of-sight, carrying devices, and dense deployment. This paper introduces a novel approach for gait analysis by passively sensing floor vibrations generated by human footsteps using vibration sensors mounted on the floor surface. Our approach is low-cost, non-intrusive, and perceived as privacy-friendly, making it suitable for continuous gait health monitoring in daily life. Our algorithm estimates various gait parameters that are used as standard metrics in medical practices, including temporal parameters (step time, stride time, stance time, swing time, double-support time, and single-support time), spatial parameters (step length, width, angle, and stride length), and extracts gait health indicators (cadence/walking speed, left–right symmetry, gait balance, and initial contact types). The main challenge we addressed in this paper is the effect of different floor types on the resultant vibrations. We develop floor-adaptive algorithms to extract features that are generalizable to various practical settings, including homes, hospitals, and eldercare facilities. We evaluate our approach through real-world walking experiments with 20 adults with 12,231 labeled gait cycles across concrete and wooden floors. Our results show 90.5% (RMSE 0.08s), 71.3% (RMSE 0.38m), and 92.3% (RMSPE 7.7%) accuracy in estimating temporal, spatial parameters, and gait health indicators, respectively. [ABSTRACT FROM AUTHOR]

The historic town of Birgi is a historic settlement within İzmir, Turkey, included in the UNESCO Tentative List of World Heritage Sites in 2012. Traditional Birgi houses, dated to the second half of the 18th and the beginning of the 20th century, are one of the best-representative and best-preserved examples of the hımış houses – the most common housing typology of the Ottoman Period. These hybrid structures include a masonry ground floor and timber frame upper floors as their primary load-bearing systems, with details shaped in line with the regional material availability and the performance of these materials, as well as technical know-how and the local experience of major historic fires and earthquakes. In this study, authentic construction techniques used in the West Anatolian Ottoman houses and information about the construction processes are presented through Birgi's traditional houses. For this aim, a visual examination and documentation of various hımış sub-typologies representative of different construction periods are conducted. The differences in construction details are evaluated in light of the predominant architectural styles and technological possibilities of their construction periods. In addition, the strengths and weaknesses of authentic construction techniques and common construction errors are discussed. [ABSTRACT FROM AUTHOR]

The mechanical performance of timber composite floors is influenced by the degree of composite action between the components. In this study, the shear strength performance of cross-laminated timber and glued laminated timber composite floors based on the joining method was evaluated by push-out test. Eight types of timber-timber composite joints were evaluated using three different methods: lag screw joints, glued-in rod joints using fully threaded bolts and glass fiber reinforced plastic, and hybrid joints. Strength characteristics were derived to make theoretical predictions on the load-carrying capacity of the joints. The results showed that the glued-in rod joints were superior to the lag screw joints, with slip coefficients and ductility measured as 10 times and 2.5 times higher, respectively. The reliability of the strength characteristics of the glued-in rod joints was remarkably different depending on the presence or absence of anti-adhesive tape applied to the timber-to-timber joint surface. The load capacity of the hybrid joint, which combines mechanical and glued-in rod joining methods, was 47% higher than that of the lag screw joint and 38% higher than that of the glued-in bolt joint. In the European Yield Model modified to estimate the load capacity of joints, the rope effect and the yield moment of the fasteners had a remarkable impact on the predicted load capacity. [ABSTRACT FROM AUTHOR]

Lorraine Plourde's book, "Tokyo Listening: Sound and Sense in a Contemporary City," explores the relationship between sound, music, and everyday life in Tokyo. Drawing on over fifteen years of ethnographic research, Plourde examines how people assign value to music and noise, and how sound can shape their perception of emotions and sensory meaning. The book is divided into chapters that focus on different contexts, including experimental music venues, classical music cafes, public spaces, and commercial establishments. Plourde's analysis highlights the ways in which sound and music can create a deep emotional effect and reshape our understanding of urban environments. [Extracted from the article]

The aim of this study was to evaluate the effect of perforated flooring beneath waterlines in broiler barns by using a camera system counting the animals and to investigate effects on animal welfare. In addition, the correlation between the number of animals and litter quality values was tested. Therefore, five experimental runs in two barns with a defined fattening period of 32 days were conducted. Each run consisted of 15,100 broilers of Ross 308 genetics of both sexes. They were split into two groups with three areas each (drinking, feeding, and comfort area) for the camera analysis and the weekly sampling. In the experimental group, frequently more broilers were counted on the perforated flooring in the drinking area with highest stocking density of 14.52 animals/m2. The control group instead had the highest stocking density with 11.92 animals/m2 in the comfort area. The correlation between animals/m2 on litter quality showed a small positive impact in the drinking and feeding area on dry matter in the experimental group. All in all, the installation of a perforated floor below the water line offers the broilers the opportunity to perform more species-typical behaviour, as they use the elevated perforated floor at night for perching as anti-predation behaviour. [ABSTRACT FROM AUTHOR]

Industry interest in mass timber hybrid construction is driving research into new connections, lateral load-resistance systems, seismic design, and fire safety design for low-carbon structures. However, only limited attention has hitherto been paid to the vibration serviceability of mass timber floor systems, which often controls their allowable maximum floor spans. This study investigated the vibration characteristics and serviceability performance of a promising modular prefabricated cross-laminated timber (CLT)–steel composite flooring solution under normal walking actions through both experimental testing and subjective evaluations. The study demonstrates that the flooring solution is a high-frequency floor system. The floor exhibits transient vibration response and can achieve acceptable vibration performance in residential and office settings. Its vibration performance can be reasonably assessed through the measured vibration dose value (VDV) over peak and root-mean-squared acceleration values when its modules are connected using self-tapping screws. The research outcomes will contribute to the vibration serviceability assessment of CLT-steel hybrid floor systems. [ABSTRACT FROM AUTHOR]

Mass-timber construction is becoming more prevalent in Australia and around the world. However, as these mass-timber buildings become taller, it is important to consider robust detailing against accidental damages to major load-bearing elements and thereby avoid potential progressive collapse scenarios. In order to better understand the robustness of typical mass-timber buildings, this study analyzed a typical 10-story midrise mass-timber building subjected to different progressive collapse scenarios. A scenario-independent approach was considered in the analysis, which includes the sudden removal of a load-bearing glulam column from the midrise mass-timber building. It was observed that when internal ties and bracings were provided, the robustness of the building was not affected as there was an alternative load path created. The orthogonal tie beam and diagonal bracing can transfer about 60% and 20% of the axial loads of the removed column to the adjacent columns, respectively. It was found that the building becomes vulnerable when no internal tie or bracing is available to transfer the accidental load. In this scenario, higher stiffness of the cross-laminated timber panel-to-panel joint can be adopted to improve the robustness of mass-timber building. [ABSTRACT FROM AUTHOR]

This study aims to tackle the drawback of non-abrasion-resistance of wood flooring with paint finish. A new method for preparing wood flooring with super-abrasion-resistant coatings by adding nano silicon carbide (SiC) particles to the paint was developed. As indicated by the results, the best mass fraction of nano SiC powder added in ultraviolet (UV) paint is 2.0%, the suspension liquid is stable when the mass concentration of sodium hexametaphosphate added is 2.5%, and it is better for the site humidity to remain below 75% when the nano SiC paint coating is applied. During the preparation of wood flooring with super-abrasion-resistant coating finish, the dosage of finish applied each time should not exceed 30 g/m2. During the sanding process, the sanding speed needs to be increased by about 2 m/s compared with that for the ordinary UV nano SiC primer in production. The test results of the performance of finished products indicate that the prepared wood flooring has better film abrasion resistance, adhesion of paint film, and film hardness. Meanwhile, because the paint film is durable and weather resistant, the service life of flooring is effectively extended, avoiding a significant waste of the product's use value and broadening the product's application range. [ABSTRACT FROM AUTHOR]

Timber floors are prone to vibration due to the reduced modulus of elasticity of the material. Composite floors represent the most convenient solution to achieve acceptable performances and at the same time to save material and cost. In determining the natural frequency of a composite floor, the stiffness of the connection between the joined structural member is crucial. Inclined screws connections are characterized by the highest slip modulus among the mechanical fastener connections. However, the determination of the optimal inclination angle of the screws for vibration and deflection reduction remains an unexplored issue. The optimization problem is faced by means of an analytical model of beam on foundation. [ABSTRACT FROM AUTHOR]