Thermal Behavior of a Light Timber-Frame Wall vs. a Theoretical Simulation with Various Insulation Materials

The objective of this paper is to compare the thermal behavior of a light frame timber wall by measuring 15 test samples with various insulation materials versus a theoretical simulation with the use of a software. This work establishes the variance between the two different methods to measure the thermal transmittance coefficient of timber walls. It is verified that the mean percentage alteration between the two methods is 4.25%. Furthermore, this approach proved that with the use of a simulation software, additional readings (humidity, vapor flux, heat flux, and vapor pressure) can also be considered and measured, enhancing the overall development of a timber wall. This can provide additional information regarding to the characteristics of the masonry’s elements assisting in an improved design of a timber wall with upgraded performance.

A Mobile System for the On-Site Assembly of Timber Frame Components: The Development of an Agile, Low-Cost Alternative to Offsite Prefabrication

Prefabricated timber component-based systems are the most prevalent industrialised system used to build housing. Along with many other countries, the UK has invested in different types of factory-based prefabrication systems as a means of increasing productivity and enhancing quality. In more recent decades, prefabrication has become part of a series of ‘modern methods of construction’ employed for, and aimed at, delivering sustainable and efficient construction. However, certain pragmatic issues remain. The industry is cyclical, and during periods of declining resources, skills and technical development can be lost. Additionally, factory-based prefabrication requires substantial initial investment and an appropriate local workforce. To help address these issues, this paper presents the concept of an alternative method of production and assembly that takes a different approach to traditional industrialised systems that involve large investments and fixed-location factories. The proposition presented in this paper is that it is possible to design and develop a small, low cost, portable micro-factory that can be taken to a temporary location or construction site, where it can then be used to construct prefabricated closed panels. We describe the development of a working prototype, effectively a micro-factory, along with its potential advantages over a fixed facility.

Research on seismic performance of traditional Chinese hall-style timber buildings in the Song and Yuan dynasties (960–1368 AD): a case study of the main hall of Baoguo Temple

The hall-style timber frame built in the Song and Yuan dynasties (960–1368 AD) is one of the most important structural prototypes of the traditional timber architecture in East Asia. The current research, through a typical case of the main hall of Baoguo Temple in Ningbo, China, aims to present an accurate and effective seismic performance evaluation method applicable to hall-style timber structures without time–cost expenditure. To obtain more realistic seismic response of hall-style timber frame, a simplified numerical model of the main hall of Baoguo Temple is established based on in situ measurements and low-cycle reversed loading tests results of mortise–tenon joints, moreover, nonlinear static pushover analysis has been performed to quantify the seismic performance levels under five loading conditions. The generalized force–deformation relationship of the timber plastic hinges is modified regarding to the moment–rotation curves of four special mortise–tenon joints. The seismic behaviour of global hall-style timber frame is evaluated through capacity spectrum method and verified by time history analysis, local failure mechanisms are evaluated by the occurrence sequence of plastic hinges. Finally, a performance-based assessment method adequate for the traditional hall-style timber architectures has been proposed with comparison to the current codes. The results have shown that the structural stiffness of the width-direction is less than that of the depth direction due to the asymmetrical configuration of the timber frame, and the building can maintain a stable state under large lateral displacement before collapsing. The inter-storey drift angles of the building under peak ground accelerations of 0.1 g, 0.2 g, and 0.3 g are less than the suggested ultimate values in the current local codes, however, the main hall represents to be more vulnerable to damage when suffer seismic action along the width-direction. This research can provide a reference for seismic performance evaluation and preventive conservation of ancient hall-style timber architectural heritage.

The structural reuse of Pinus Radiata in New Zealand

<p>Masses of used Copper chromium arsenic (CCA) treated timber is deposited into landfill from light timber framed building deconstruction every year. This research explores the structural integrity of CCA treated timber and the feasibility of its re-use within the construction industry. To answer this question an appropriate methodology has been designed to achieve quality results. The first part of the methodology was to identify the profit margin for pinus radiata through communicating with individuals in the current market. This market all works around the concept that to reuse there needs to be a significant buying community as it needs to generate MONEY. Through doing this it was identified that only a few companies in New Zealand reuse CCA treated timber and the ways of which it is re-used varies greatly between companies. Some firms pull the nails out due to health and safety reasons, while others leave them in due to the overall cost of the sale. This gives a good understanding on what everyone is doing across the country and allows for the sale market to be set at $2.00 a meter, which if done correctly comes in at around $0.16 a meter of profit. The next part of the methodology required a physical assessment of material itself in order to establish its structural integrity and identify other potential barriers to its reuse. This section covered all other possibilities to pinus radiata focusing on the different timber which have the same properties, and focus on separate treatments which will also conduct the same issues as CCA. This all found that there is much research to consider, which placed New Zealand in an area of profit, as any of these documents could be the focus point and all could eventually relieve CCA from the industry. Existing research identifies how the use of CCA treated timber can be prevented, but does not consider the diversion of existing treated timber being deposited into landfill. The lack of research into the re-use of CCA treated timber is the main barrier found in this thesis. This required the series of events which occur between building deconstruction and deposition into landfill to be clearly defined, before they could be changed. The changes to how CCA treated timber is processed after deconstruction has the potential to divert the material from landfill for re-use. The primary addition to this process was an assessment of the strength which it holds. To accomplish this a three point bending test was carried out on each member, finding the alternate strength and the modulus of elasticity (MOE). These two figures could then be directly compared to NZS 3603:1993 timber structural standards allowing their long term history of testing to be the comparative point (New Zealand Government, 1993). With the two figures it was found that all of this material strength was 91% above the minimum strength grading of SG6, and 55% above the next area of SG8, which is the most commonly used framing timber. Although through doing this there was hope for the material to present themselves with a way of finding the general strength with minimal tools, this is not present in the research. The most important finding of this research is that CCA treated timber is strong enough to be placed straight back into the construction industry and re-used for light timber frame construction. Future research is needed into the additional education required of builders in order for them to confidently re-use the timber in construction.</p>

The structural reuse of Pinus Radiata in New Zealand

<p>Masses of used Copper chromium arsenic (CCA) treated timber is deposited into landfill from light timber framed building deconstruction every year. This research explores the structural integrity of CCA treated timber and the feasibility of its re-use within the construction industry. To answer this question an appropriate methodology has been designed to achieve quality results. The first part of the methodology was to identify the profit margin for pinus radiata through communicating with individuals in the current market. This market all works around the concept that to reuse there needs to be a significant buying community as it needs to generate MONEY. Through doing this it was identified that only a few companies in New Zealand reuse CCA treated timber and the ways of which it is re-used varies greatly between companies. Some firms pull the nails out due to health and safety reasons, while others leave them in due to the overall cost of the sale. This gives a good understanding on what everyone is doing across the country and allows for the sale market to be set at $2.00 a meter, which if done correctly comes in at around $0.16 a meter of profit. The next part of the methodology required a physical assessment of material itself in order to establish its structural integrity and identify other potential barriers to its reuse. This section covered all other possibilities to pinus radiata focusing on the different timber which have the same properties, and focus on separate treatments which will also conduct the same issues as CCA. This all found that there is much research to consider, which placed New Zealand in an area of profit, as any of these documents could be the focus point and all could eventually relieve CCA from the industry. Existing research identifies how the use of CCA treated timber can be prevented, but does not consider the diversion of existing treated timber being deposited into landfill. The lack of research into the re-use of CCA treated timber is the main barrier found in this thesis. This required the series of events which occur between building deconstruction and deposition into landfill to be clearly defined, before they could be changed. The changes to how CCA treated timber is processed after deconstruction has the potential to divert the material from landfill for re-use. The primary addition to this process was an assessment of the strength which it holds. To accomplish this a three point bending test was carried out on each member, finding the alternate strength and the modulus of elasticity (MOE). These two figures could then be directly compared to NZS 3603:1993 timber structural standards allowing their long term history of testing to be the comparative point (New Zealand Government, 1993). With the two figures it was found that all of this material strength was 91% above the minimum strength grading of SG6, and 55% above the next area of SG8, which is the most commonly used framing timber. Although through doing this there was hope for the material to present themselves with a way of finding the general strength with minimal tools, this is not present in the research. The most important finding of this research is that CCA treated timber is strong enough to be placed straight back into the construction industry and re-used for light timber frame construction. Future research is needed into the additional education required of builders in order for them to confidently re-use the timber in construction.</p>

Rotational Stiffness and Carrying Capacity of Timber Frame Corners with Dowel Type Connections

With the development of wooden structures and buildings, there is a need to research physical and numerical tests of wood-based structures. The presented research is focused on construction and computational approaches for new types of joints to use in wooden structures, particularly glued lamella elements made of wood and wood-based composites. This article focuses on improving the frame connection of a wooden post and a beam with the use of fasteners to ensure better load-bearing capacity and stiffness of the structure. In common practice, bolts or a combination of bolts and pins are used for this type of connection. The aim is to replace these commonly used fasteners with modern ones, namely full thread screws. The aim is also to shorten and simplify the assembly time in order to improve the load-bearing capacity and rigidity of this type of frame connection. Two variations of the experimental test were tested in this research. The first contained bolts and pins as connecting means and the second contained the connecting means of a full threaded screw. Each experiment contained a total of two tests. For a detailed study of the problem, we used a 2D or 3D computational model that models individual components, including fasteners.

Seismic Resistance of Timber Frames with Mud and Stone Infill Walls in a Chinese Traditional Village Dwelling

Traditional Chinese wood residences consist of timber frames with masonry infill walls or other types of infill, representing valuable heritage. A field investigation of traditional village dwellings in northern China consisting of timber frames with mud and stone infill walls was conducted. Their construction characteristics are reported, and static cyclic tests were performed on two full-size wood-stone hybrid walls with different configurations (exterior transverse wall and internal transverse wall) and no openings (doors or windows). Their failure mechanics and seismic capacity, i.e., the strength, stiffness, ductility, and energy dissipation, were investigated. The results are compared with a previous experimental study of two full-size timber frames with the same traditional structure but no infill to determine the effect of the mud and stone infill on the lateral resistance. The experimental results indicate that the stone infill has a critical influence on the lateral performance of traditional village buildings, resulting in a high lateral stiffness, high strength (>20 kN), and a high ductility ratio (>10). An increase in the vertical load leads to an increase in the lateral resistance of the timber frame with infill walls, larger for the internal transverse wall than the external gable wall. The incompatibility of the deformation between the timber frame and stone infill is the main failure reason, resulting in falling stones and collapse with undamaged timber frames. Suggestions are provided for the protection and repair of traditional wood residences in northern China.

Earthquake Damage Reduction in Timber Frame Houses Using Small-Size Fluid Damper

Timber frame structures are common traditional methods of housing construction, which use squared-off timber beams, columns, and walls as lateral load-bearing members. The seismic performance of timber frame houses can be secured by the load-bearing capacity of erected braces and walls; however, past major earthquakes have caused severe damage to earthquake-resistant timber frame houses. This study investigates the effect of small-size fluid dampers on the earthquake damage reduction in a timber frame house through earthquake response analyses. A detailed analytical model was generated based on an actual two-story timber frame house, which was designed for the highest seismic grade using the latest Japanese standards. Time-history response analyses were carried out for the analytical model subjected to the 2016 Kumamoto earthquake with and without small-size fluid dampers. The small-size fluid damper is equipped with a relief mechanism for the damping force, and its damping property can be expressed using the Maxwell model. Four or seven fluid dampers were installed in the first story of the model to investigate their effect on the earthquake damage reduction. The results of the earthquake response analyses show that the four and seven fluid dampers can reduce the maximum first-story drift angle by approximately one-third and half, respectively. The dampers suppress the residual deformation, control the elongation of the fundamental period during the response, and restrain the amplitude growth. A small-size fluid damper has an equivalent quake resistance to a conventional structural wall with a wall ratio of 3 plus.