Wooden Buildings Research Articles

Fire safety study of a perlite concrete chimney and wooden ceilings used in buildings based on experimental tests and CFD analysis

The operation of fuel-burning heating equipment results in soot build-up in the flues. Its ignition poses a significant fire risk to the building, as the flue temperature can reach 1000°C. Wooden structural elements located near the chimney (ceilings and roof penetrations) are particularly vulnerable. To date, research has focused on the fire safety of wooden ceiling elements. This is where, due to heat radiation from the chimney, wooden elements significantly increase their temperature and become the location of fire initiation in the buildings. The task of chimney designers is to limit the temperatures of heated wooden building components near these structures. The present work analysed a ceramic and concrete chimney with air space with an innovative perlite concrete casing with a dual-function (load-bearing and thermal insulation). Computational Fluid Dynamics (CFD) analyses verified by a full-scale experiment were conducted to evaluate the fire safety of wooden building ceilings. The tests showed that a high level of safety characterised the chimney under study. The maximum temperature of the casing when testing the soot fire reached 38°C, and the wooden elements simulating the ceiling reached 28°C - this result is almost four times better than the chimney standard requirement. Furthermore, a developed CFD model exhibited high accuracy compared to the experimental results and can be used for designing this type of chimney and other research and expert work, such as that performed after fires in buildings originating from the chimney. Practical Application The article describes CFD analyses and tests of an innovative chimney in a perlite-concrete casing. The described research showed the high safety of such a chimney during soot fires. The results obtained can be used to develop changes in standards to improve the safety of chimneys and design safer and more efficient ones. The author’s chimney model and CFD analysis make it possible to determine the temperatures in the chimney during a soot fire. This CFD model allows you to assess the fire safety of the chimney and the building elements located in its vicinity.

MATERIAL INVENTORY INFORMATION SYSTEM AT UD. ALAM RAYA WEB-BASED USING THE WATERFALL METHOD

UD. Alam Raya is a trading business engaged in the sale of building materials. UD. Alam Raya provides various types of building materials such as wood, nails, cement, iron, electrical tools, pipes, glue, and other building materials. In processing inventory and finances are still not computerized. Recording of sales transactions and purchases of goods is still done manually on notes and large sheets of paper grouped by transaction date. Recording on paper media is less effective because when the paper is exposed to water, the writing on it also fades, hindering the process of making financial reports. Based on these problems, a computerized building material inventory information system is needed in order to facilitate sales and purchase data processing as well as financial reports at UD. universe. This study uses qualitative research methods and the waterfall software development method, as well as the PHP (Hypertext Preprocessor) programming language using the CodeIgniter framework. This research succeeded in designing and creating a building material inventory information system at UD. universe. The benefit of this building material inventory information system is that it makes it easier to make purchase reports, sales reports, and financial reports at UD. universe

Evaluating the environmental performance of 45 real-life wooden buildings: A comprehensive analysis of low-impact construction practices

Buildings are responsible for 37 % of global Greenhouse Gas (GHG) emissions. Subsequently, stakeholders in this sector have introduced different strategies to reduce the environmental impact of buildings. One strategy focuses on increasing the use of wood in buildings as a low-impact material with the potential to act as a carbon sink. Although research shows a tendency towards lower GHG emissions from wood structures compared to conventional constructions, the existing literature is typically challenged by methodological inconsistencies and only assesses a limited number of building projects at a time. As a result, uncertainties are introduced about comparisons between them, how their background and modeling assumptions may vary, as well as the integrity of the assessed solutions. Hence, this study analyses 45 cases of buildings applying the same methodology to enable a comprehensive understanding of the environmental performance of wooden buildings, identifying common trends, challenges, and best practices. This study finds that the embodied impacts contribute highly to the environmental impact and thus remain essential to consider. However, there is a very weak correlation between the quantities of wood used in the buildings and the environmental impact for wooden buildings, but a strong correlation between the quantities of insulation, plastics, composites, and POCP, ODP, ODP and EP, respectively. Therefore, the use of these materials should be optimized to further reduce the environmental impact of wood buildings.

Hygrothermal performance of hempcrete in a multi-layer wall envelope

Hempcrete is a promising self-bearing thermal insulation material, as it has low thermal conductivity and a minor to negative CO2 footprint. It is also believed to be applicable not only in building construction, but also for renovation or additional insulation, since hempcrete hygrothermal properties are compatible with wooden structural elements. To utilize it efficiently, it must be possible to make predictions regarding hempcrete hygrothermal performance and whether it is up to the modern standards — this requires a verified material model for use in numerical simulations. Previously, we have shown that hempcrete by itself performs well as insulation for building wall envelopes, and we have validated a material mode for hempcrete. This study assesses, both experimentally numerically, if hempcrete is suitable for use in multi-layer envelopes. A multi-layered wall envelope of a wooden multi-story building was insulated from the inside with hempcrete blocks. Relative humidity and temperature within the wall, as well as heat flow, were monitored over ∼2 years. The wall envelope was modeled numerically using WUFI. Temperature and humidity dynamics predicted numerically are in good enough agreement with experimental observations. In addition, the mold risk forecast derived from simulation and experiment results agree rather well with actual observations — no mold risk was predicted, and no mold was observed upon inspection. All of this suggests that hempcrete could indeed be used as a part of multi-layer building insulation envelopes, at least for climate conditions sufficiently similar to Latvian.

Architectural Heritage Preservation for Rural Revitalization: Typical Case of Traditional Village Retrofitting in China

With the massive urbanization and industrialization in China, the paradox between fast modernization and cultural preservation arouses challenges on new insight into green construction and sustainable development strategies throughout the nation. Particularly, how to strike a balanced cultural–modern rural revitalization has become a research priority, especially for cultural and historical villages in relatively under developed western regions. In this paper, taking Gaotunzi Village, a traditional ethnic village in western high-altitude plateau as an illustrative example, the typical green design manner and optimization strategy are proposed for cultural and architectural heritage preservation. The detailed architecture and structure design is conducted for both old temple retrofitting and new museum construction, with consideration for retaining traditional building colors, styles, and materials. Moreover, land use planning is demonstrated for local public space and services upgrading. The overall design strategy has been taken into practice for the local renovation construction program. The preliminary results indicate that this green retrofitting idea and approach are quite locally feasible for sustainable rural revitalization with local heritage conservation, including traditional wooden buildings, Buddhism belief, Tibetan icons, and ethnic symbolic culture preservation and promotion. This work can provide a typical design reference and application prototype for rural construction and modernization with local heritage preservation considerations, especially for those traditional villages in developing countries.

Ritual Practice at Late Iron-Age and Viking-Age Cemeteries in Norway: The Mortuary Houses From Skeiet, Vinjeøra

THREE PROPOSED LATE IRON- AND VIKING-AGE MORTUARY HOUSES were recently excavated in Central Norway. Excavations and geoarchaeological investigations imply underground wooden buildings resembling domestic houses with doors. Radiocarbon dating indicates three succeeding buildings dating c AD 500–950. The finds included animal and food sacrifices. With their funerary context, the buildings provided an opportunity to frequently visit and interact with mortuary remains, as part of the rituals practised at cemeteries. They provided a ritualised space between the living and their dead relations.

The Effect of Wooden Building Materials on the Indoor Air Quality of Houses

This work focuses on researching wood as a low-emitting building material. Many studies showed that by regulating the emission of adverse chemicals from pressed wood products, they could be recycled as low-emitting materials. The presented case study, shows the measurements of the indoor air quality in a passive, low-energy, wooden, light frame house. Concentrations of Volatile Organic Compounds (VOC) and formaldehyde were measured and compared with data from other case studies made in this subject and with the current Hungarian and international regulations of adverse chemicals. The main VOC materials which concentrations were significant in all measurements were terpenes (limonene, alpha-pinene, 3-carene), aliphatic-hydrocarbons and aldehydes (acetic acid, 2-Methoxy-1-ethylmethyl acetate). The comparison showed that the concentrations of benzene, toluene, naphthalene, formaldehyde, and styrene were not deviant from the average values measured by other case studies. The observations showed that the main influencing factors of indoor air quality were the changes in indoor temperature, relative humidity, air exchange rate, and human activities. The conclusion is that the wooden materials applied in the house are low-emitting materials and do not pose a health risk for people.

Макроэкономические тенденции развития Дальнего Востока России в первой половине 2024 г.

Based on operational statistical, analytical and expert information, an analysis of the economic and social situation in the Far Eastern Federal District in the first half of 2024 is carried out in comparison with 2022–2023. It is shown that while instability and contradictory development trends in certain sectors of the economy persist, a sharp decline in the macroeconomic context is not observed. The output index of basic economic activities shows positive dynamics, but the active growth rate has slowed down. This does not currently allow us to talk about a stable phase of economic growth. The formation of growth rates in the industry of the Far Eastern Federal District was positively influenced by an increase in mining production for the main raw materials, an increase in the production of aviation and engineering products, certain types of non-metallic mineral products, and prefabricated wooden building structures. The positive dynamics and growth of investments in fixed assets were associated with the implementation of large investment projects in the field of railway and port infrastructure, mining, and manufacturing. There is a high level of inflation despite tight monetary policy. Consumer demand continues to expand in certain categories due to the growth of real incomes of the population

History and Prospects of Development of Low-Rise Wooden Buildings in Cities of the North of Russia

Low-rise timber buildings are an important part of Arctic cities. This is due to a number of factors: the traditions of using wood in construction, accessibility and simplicity, mastery of the technology of processing wood as a building material, the ability to quickly construct buildings from ready-made elements, high thermal qualities of wood. The modern emergency low-rise wooden building fund has discredited itself, which has led to an increase in the construction of capital multi- apartment buildings using technologies from cities in central Russia. Currently, economics, ecology, and the development of modern technologies dictate the need to revive low-rise wooden residential buildings at a new qualitative level, including the development of a new typology of residential buildings that meet the diverse modern requirements of the population of Arctic cities.

Acoustic performance analysis of wooden structure building wall by integrating BIM technology and impedance tube method.

With the increasing demand for building acoustic performance, accurately evaluating the acoustic performance of building walls has become an important research topic. However, existing research has mostly focused on general building materials such as concrete, iron and steel, and glass. For wooden structure wall, due to the sound absorption performance of the materials themselves and the complexity of structural design, the analysis of their acoustic performance is still relatively weak. Moreover, there is a lack of quantitative description of their spectral characteristics and acoustic impedance. To analyze the acoustic performance of wooden structure building walls, Building Information Model (BIM) and impedance tube method were integrated to construct a building wall performance testing system with BIM technology. The impedance tube method was applied and testing functions for sound absorption and insulation performance were designed. The outcomes indicated that in the error test, the error range between the experimental group and the control group was [0.01, 0.18], indicating a high reliability of the experimental results. In the calculation of sound insulation of different specimens at different sound frequencies, when the frequency was 1600Hz, the sound insulation of the control group and experimental group was 65.30dB and 70.14dB, proving the effectiveness of the design method. The above results demonstrate the practicality of integrating BIM technology and impedance tube method in the acoustic performance analysis of wooden structure building walls. This study provides strong technical support for reducing the indoor environment of wooden buildings and improving the comfort of people's living environment.

RETRACTED ARTICLE: Application of wireless sensors and deep learning algorithms in comfort analysis of wooden structures

In many buildings with wooden structures, the service life and comfort of the floor will be affected by the walking load of the human body. The vibration effect generated by the human walking on the floor will affect the comfort that the floor brings to people. This article primarily focuses on the study of the correlation between floor vibration and human walking load in wooden buildings. It provides an analysis and summary of research findings from both domestic and international sources. Furthermore, the data collected is utilized to establish a model for estimating human walking load. The advent of information technology has witnessed significant transformative changes spurred by shifts in societal needs. Notably, the establishment of wireless sensor networks stands as a significant milestone within the field of information technology, highlighting advancements in science and technology. The evolution of wireless sensor networks has proven instrumental in various sectors within China, including but not limited to the military, environmental monitoring, biological research and medical systems, disaster monitoring, and energy allocation. This paper uses deep learning algorithms to analyze the node deployment problems of wireless sensor networks, summarizes a reasonable node deployment plan through specific research and practice, and uses collaborative deep learning methods to improve the operating efficiency of the network. In addition, this article also tested the vibration effect of wood structure buildings, analyzed different influencing factors, and provided a good reference point for the formulation of wood structure comfort standards.

Model for Determining Follow-up Actions in Slum Areas in North Sumatra: Case Study in Tebing Tinggi City

Even in various cities, inadequately habitable residential areas tend to become slums and no longer meet the standards of a healthy residential environment. This study utilizes descriptive analysis and multiple linear regression analysis with a total of 100 respondents. The Slum Environment Follow-up Determination Model shows the results of the settlement conditions in Tebing Tinggi City, where many people live in unsuitable places, with damaged or inadequate building structures, high housing density, and wooden buildings. As a result, they are vulnerable to fire hazards. Additionally, there is a lack of clean water services, drainage facilities, household waste disposal, waste management, and poor environmental road quality (many roads lack upper pavement or are dirt roads), as well as inadequate street lighting. The low levels of education and income indicate a low socioeconomic status in the slum areas of Tebing Tinggi City. Factors such as Building Density Level (BDL), Environmental Drainage, income, and education collectively significantly influence people's decisions to live in slum environments. However, factors such as Building Density Level (BDL), Environmental Drainage, income, and education partially influence people's decisions to live in slum environments. The pattern of community participation in tackling slum areas remains the same, with an average of 57% not participating in decision-making, implementation, achievement, and program result evaluation.

Half-scale shaking table tests of two brick and wood buildings: Effect of the engineered cementitious composites strips retrofit system

In order to study the feasibility of using the retrofit system of engineered cementitious composites (ECC) strips for strengthening Chinese rural brick and wood structures. Two half-scale buildings, one was the unreinforced building and the other was reinforced by ECC strips, were placed on the shaking table to apply various levels of seismic excitations. The comparisons between the unreinforced building and the retrofit building were analyzed regarding the natural frequency, maximum responses of acceleration and displacement, as well as the dynamic characteristics, torsion effect, global hysteresis response, and seismic behavior evaluations. Test results demonstrated that the ECC strips retrofit system significantly enhanced the stiffness, ductility, damage tolerance, and reduced the seismic displacement response of the structure. Meanwhile, the retrofit building was able to dissipate more energy with increasing magnitudes of earthquake excitation. Such an in-depth analysis provides a reference for the application of ECC strips to retrofit brick and wood structures.

Wood Building Construction: Trends and Opportunities in Structural and Envelope Systems

Wood Building Construction: Trends and Opportunities in Structural and Envelope Systems

Time demands of traditional hand-hewing techniques for sustainable repair of wooden heritage structures: A comparative study

The hand-hewing of timber has been a fundamental skill for carpenters throughout history. Inevitably though, the majority of wood used in construction at the present time is processed with the use of machines. Repairing heritage objects with machined wood however, as opposed to working replacement timber using similar craft methods and tools as those used in the original, is often in conflict with the principles set forth in the Venice Charter for the Conservation and Restoration of Monuments and Sites. Ultimately, relying on mechanization is a missed opportunity to contribute to the preservation of valued intangible cultural heritage.Whereas the sustainability of traditional woodworking techniques and technologies can be promoted by applying them in the conservation of historical wooden buildings, the labor-intensive and time-consuming nature of manual woodworking makes feasibility questionable. In order to provide valuable insight for planners and monument care workers, the paper presents a study on the time demands associated with processing hand-hewn beams intended for use in the structural repair of wooden heritage objects.A series of experiments was conducted wherein a total of 94 beams 18×22 cm in profile and 2.5 m in length were hewn from spruce logs of various diameters. The relationship between initial log diameter and required processing time is presented as a linear function. The relative proportions of the individual steps to the hewing process as a whole were also documented and showed a clear dependency on the total amount of material removal required. The overall processing time was significantly reduced in the case of timber that was soaked for several months before being hewn into beams, and the low-work hewing technique was shown to be more efficient in comparison to high work on trestles.This paper has been published in memory of Petr Růžička, the great pioneer of forgotten carpentry techniques whose work opened a window to our past for future generations.

Shake Table Testing and Modeling of New Zealand Light-Frame Wood Buildings

Shake Table Testing and Modeling of New Zealand Light-Frame Wood Buildings

Experimental study on reduction of floor impact sound in wooden buildings

In recent years, wooden buildings have been attracting attention from the viewpoint of promoting sustainable construction through the use of wood. In Japan, laws promoting the use of wood have been enacted and the number of wooden apartment buildings is increasing. However, the structural members used in wooden buildings are lighter and less rigid than those in reinforced concrete buildings, so sound insulation performance is generally poor. In particular, it is difficult to achieve good insulation performance against heavy floor impacts. In this paper, we describe a study that was conducted for the purpose of reducing floor impact sound in wooden buildings. The ability of two damping materials developed by the authors to reduce floor impact sound was tested. One is a damping material for floors that acts like tuned mass dampers (TMDs) to reduce floor vibrations. The other is a damping material for ceilings that is inserted above the ceiling panels to increase ceiling damping and attenuate vibration. These countermeasures were experimentally tested in a building constructed using the wooden frame wall method (two-by-four system) and their ability to reduce floor impact sound was confirmed.

Performances of low frequency impact sound in wooden buildings

Since 1999 Sweden has required an extended frequency range for sound insulation in residential buildings, using 50 Hz as the lower limit. This regulation update has driven the design and development of multi storey residential building systems with wooden structures in a positive direction. Already in the mid 1980'ies there existed scientific proof that it the perceived impact sound will improve if the frequency range was extended below the lower standard limit 100 Hz at that time. Lately, researchers have indicated that the perceived impact sound can be even further improved if the frequency range is extended below current lower standardized limit of 50 Hz. Assume that the frequency range for impact sound requirement will be further extended to include frequencies from 25 Hz, what would that mean for modern wooden apartment buildings? Acouwood and Kuster & Partner AG are collecting data from 20 Hz, no matter if the standard measurement procedure cannot be applied below 50 Hz. It gives a good overview of potential annoyance risk but also of acoustic performances of modern sustainable multifamily buildings and how they can be improved. This paper summarizes measurement results of impact sound from 20 Hz in several wooden buildings.

Current Performance of Floor Impact Sound Insulation in Wooden Apartment Buildings in Hokkaido

In Hokkaido, Japan, technological developments have been introduced to improve the floor impact sound insulation performance in wooden apartment buildings. However, such technological developments are not widely used, especially in rental properties. To effectively disseminate the required technology, it is vital to report examples of implementation. Therefore, we measured the performance of five types of wooden apartment buildings with high sound insulation performance and analyzed the results. The main results are listed below. (1) A relatively high performance was obtained by installing a floating floor and an independent ceiling. (2) For heavy weight floor impact sound insulation of a car tire source, a floating floor with a surface density of 60 kg/m2 or higher could achieve a performance of Li,Fmax,r,H(1)-60 or higher. However, in the case of a rubber ball source, vibration radiation noise from the wall surface of the lower floor is large, so it is necessary to consider vibration countermeasures. (3) For light weight floor impact sound insulation, sufficient performance cannot be obtained even with a floating floor. Therefore, carpet or wooden soundproof flooring should be used. (4) The light weight floor impact sound pressure level is high when the floor area of the sound receiving room is small.

A literature review of floor impact noise characteristics in wooden apartment buildings using cross-laminated timber slab

In this study, the floor impact noise characteristics of wooden apartment buildings made of cross-laminated timber (CLT) slabs were analyzed through a literature review. Data on heavy-weight impact noise performance was gathered, including information on floor components such as floor topping materials and ceiling finishes. The collected data was primarily analyzed in terms of CLT slab thickness. The results showed that 150 mm-thick bare CLT slabs had a single number rating of 70 to 77 dB when tested with a rubber ball, but this decreased to 64 dB for a 210 mm-thick bare slab. The addition of lower ceiling finishes and floor-topping materials could reduce the heavy-weight impact noise level to around 50 dB. However, results using a bang machine indicated 5 dB higher levels than those obtained with the rubber ball. The floor impact noise characteristics of CLT structures were also compared to those of concrete structures. The paper concludes by discussing directions for improving the floor impact noise isolation performance of CLT buildings.