Traditional Wooden Frames Research Articles

Diversity and Variation in China's Yao Ancient Wood Frame Structures Through Genetic Algorithms

This study, focusing on the China's Yao minority community, investigates the feasibility to create a generative computational method to replicate the diversity of the existing Yao traditional wood buildings, addressing the critical issues currently facing computational design methods, in the attempt to adapt genetic-generative algorithms to the study of local ancient architecture. The project develops a computational tool to generate a network of three-dimensional prototypes, or building structures, derived from traditional wood frame village houses. It studies possible housing structures that illustrate some of the key working methods available in digital systems such as ‘generating' and ‘compositing' taking as a starting point computational strategies oriented towards geometry and where a set of local variables play a decisive role: available local technologies, use of raw materials, and the dimensioning of timber components based on data collected from Yao architecture.

Lateral loading performance of end narrow panel reinforced light wood frame shear walls

PurposeThe sheathing panels of traditional light wood frame shear walls mainly use oriented strand board (OSB) panels, and the damage of the traditional walls is mainly caused by the tear failure at the bottom corner of the OSB panel. In order to improve the lateral performance of the traditional light wood frame shear wall, a new type of end narrow panels reinforced light wood frame shear wall is proposed.Design/methodology/approachThe monotonic loading tests and finite element analysis of nine groups of walls, with different types of end narrow panel, types of fasteners used on the end narrow panels and the end narrow panels edge fastener spacing, are carried out. The effects of different characters on lateral performance of light wood frame shear walls are reported and discussed.FindingsThe failure modes of the wall reinforced by parallel strand bamboo narrow panels with 150 mm edge nails spacing are similar to the traditional wall. Conversely, the failure modes of other groups of walls reinforced by end narrow panels are the tears of the bottom narrow panel or the bottom beam. The end narrow panel reinforced light wood frame shear wall can make full use of the material property of sheathing panels. Compared with the lateral performance of traditional walls, the new-type end narrow panels reinforced walls have better lateral performance.Originality/valueA new type of end narrow panels reinforced light wood frame shear wall is proposed, which can enhance the lateral performance of the traditional light wood frame shear wall. The new-type walls have advantages of convenient operation, manufacture cost saving and important value of engineering application.

Seismic performance of Chinese traditional timber frames

Chinese traditional timber frames are known for their mortise-tenon joints and wooden planks shear walls. To investigate the seismic behavior of the structural system, three full-scale timber frames were subjected to in-plane quasi-static loading. The hysteresis characteristics, lateral load-carrying capacities, lateral stiffnesses, and energy dissipation capacities of the timber frames were investigated. The results showed that the hysteretic loops of all specimens exhibited pinching, and the column and beam components were nearly intact after the test. The traditional wooden frames had large deformability. The installation of the infilled timber shear wall brought great improvements in lateral resistance and energy dissipation to the bare frames. The initial stiffness of the timber frame infilled with timber shear wall was 0.113 kN/mm, which was 56.9% and 11.9% greater than those of the bare frame specimen F1 and specimen F2, respectively. The results from the experimental analyses can serve as a technical basis for the development of seismic design methods and strengthening designs of such structures in practical engineering.

A Critical Investigation of the Wood Frame System: The Case for the Neil Astle House

The traditional wood framed house has been a mainstay of the building industry and a dominant force on the American cultural landscape. With rare exceptions, its enormous effectiveness has seldom led to a serious questioning and challenging of what it means ‘to build’. The act of building should be a reflective act, one that recognizes repercussions and limitations. One architect whose methodology challenged the residential construction paradigms and questioned how we build is Nebraska architect Neil Astle, who reenvisioned an alternative to traditional wood frame construction in the design of his house using small wood scantling.

大断面横架材を有する2スパン伝統木造軸組の耐震要素配置と力学特性

In seismic evaluation methods based on limit strength calculation, a shear force with a one-to-one correspondence with a load-bearing element is defined, and the shear force of construction only adds the restoring forces of the element. However, the specifications of traditional joints and element position may vary, and the calculation method does not depend on these specifications. Some previous studies have considered the specifications of traditional joints such as column-to-beam (Sashigamoi) joints based on element experiments and simulation analysis. However, the influence of element position on the structural properties and the behavior of traditional wooden frames with large section beams (Sashigamoi) based on multi-span frame experiments has been addressed in few studies. Japan has experienced numerous earthquakes, and there are many reports of traditional wooden structures collapsing because of earthquakes. However, many traditional wooden structures remain sound and unaffected and are extremely interesting. Evaluation of the seismic performance of such traditional wooden buildings may be significant in preventing damage to buildings and ensuring safety. Against this background, this paper presents the results of static cyclic loading tests and simulation analysis for four traditional wooden frames in order to understand the seismic performance of frames with uneven large section beams (Sashigamoi) and to clarify the influence of the beams and shapes of fitting-type joints on the behavior of the whole frame. Major findings of the present work are as follows: (1) First, static cyclic loading tests were conducted on four traditional wooden frames; the number of frame spans, the presence or absence of large section beams (Sashigamoi), and the position of beams were considered as the parameters. Two-span frames underwent column splitting or column breaking more readily and with smaller deformation than in the case of one-span frames. In addition, the shear forces exhibited directional dependence, which is attributed to the asymmetry of the frames or the shapes of the column-beam joints. (2) Second, a method for modeling traditional fitting-type joints was developed. This method can be used to analyze traditional wooden frames with large section beams (Sashigamoi). Simulation analysis results were in good agreement with the test results. (3) Finally, a parameter study about the aspect ratio of the frame, large section beam position, and beam height distance was carried out, and the restoring force was verified. The smaller the beam height distance, the smaller was the difference in the restoring force with the loading direction.

NONLINEAR ANALYSIS OF JAPANESE TRADITIONAL WOODEN FRAMES WITH FITTING-TYPE JOINT

This paper reports our research project on the seismic performance of traditional wooden frames with large-section beams. First, based on past cyclic loading tests on four frames, a simple analysis model of a fitting-type joint was constructed using beam elements. Next, past experimental results were simulated by the model. Finally, a sensitivity analysis was performed to study about the effect of height arrangement of beams on the performance of the whole frame. The major findings of this study are as follows: (a) Some material tests are conducted for wooden test pieces cut down from all column of specimens. The compressive spring properties are decided. (b) Analysis models are constructed, and the restoring forces of frame specimens are simulated precisely. (c) The relation between height arranging beams and the change in restoring force is considered by sensitivity analysis.

Seismic Evaluation of Structural Insulated Panels in Comparison with Wood-Frame Panels

Structural Insulated Panel (SIP) wall systems have been used in residential and light commercial buildings for the past sixty years. Lack of sufficient published research on racking load performance and limited understanding of the influence of fastener types on seismic response has been a deterrent in widespread use of the wall system in seismically active areas. This paper presents the results of a study involving a total of twenty one 2.4 m × 2.4 m shear walls tested under monotonic and cyclic loading. Four different 114 mm thick SIP panel configurations and one traditional wood frame wall were tested under monotonic loading according to ASTM E 564-06; and thirteen 114 mm thick SIP panels and three wood frame walls were tested under the CUREE loading protocol according to ASTM E 2126-11. Parameters such as fastener type; spline design; hold-down anchor location; and sheathing bearing were adjusted throughout the testing in order to determine their effects on the SIP’s performance. Performance parameters such as peak load and displacement; energy dissipation; allowable drift load capacity and seismic compatibility were determined for all of the specimens. Such parameters were then used to demonstrate the SIP walls’ compatibility with the wood frame walls and to determine the efficiency of the different SIP wall configuration and spline systems employed.

Vapour retarders in wood frame walls and their effect on the drying capability

Wood frame walls typically need a vapour barrier at the warm side to avoid interstitial condensation due to vapour diffusion and air leakages from the interior. A more vapour open material than the traditional vapour barriers, here called vapour retarder, could allow condensed moisture, built-in-moisture or moisture from minor leakages to dry to the interior in addition to the outward drying. The application of permeable vapour retarders in wood frame walls have been investigated in this study by the use of a hygrothermal simulation tool. A traditional wood frame wall usually has good drying possibilities to the exterior. If a vapour retarder should have an effect on the total drying, it must not be too vapour tight. The purpose of this study was to find some threshold value for the maximum vapour resistance of a vapour retarder—when a requirement is that it should have a relatively large effect of the total drying of the wall. The increased risk for condensation as the vapour resistance decreases has however not been investigated in this study. In general it was found that permeable vapour barriers have relatively little effect on the total drying of ordinary wood frame walls in a Nordic climate.

FULL-SCALE SHAKING TABLE TESTS OF TRADITIONAL WOODEN FRAME

In order to evaluate the dynamic characteristics (natural period, equivalent viscous damping ratio, etc.) of traditional wooden frames, full-scale shaking table tests were performed. In these tests, the following types of specimens were included; 1) frame with hanging wall, 2) frame used non-slipping-out wedge, 3) frame installed Zn-Al dampers.Zn-Al damper and Non-slipping-out wedge were developed by the authors. As a result, horizontal displacement became from 27 to 37% smaller and equivalent viscous damping ratio became from 57 to 162% larger by using Zn-Al damper.Finally, seismic response analyses were conducted. Based on the static loading test, the hysteresis model of the joint part was made for analysis.

Hysteretic Behavior of Korean Traditional Wooden Frames

The objective of this paper is to provide basic information on structural behavior of Korea traditional wooden frames under earthquake loading. One of prototype wooden frames for this study was chosen from a designated national treasure in Korea. A series of experimental work were prepared to investigate the behavior and hysteresis characteristics of traditional wooden frames under cyclic lateral loading. Three test specimens of a full scale were performed for cyclic hysteretic behaviors based on one static test specimen as a pilot test. The experimental observation showed stiffness degradations and slips after experiencing initial yield point and the first cycle at a new larger displacement due to inherent gaps in connections between columns and connection parts of beams and a gradual indentation of interfaces under pull and push. Addition of structural components such as an upper beam and clay-filled wall to the basic beam and columns increased the initial stiffness, strength and energy dissipation than those of basic frames. The behaviors of the wooden frames were simulated by DRAIN-2DX program for the dynamic analysis of an entire wooden frame system. Comparison between analysis models and the experimental behaviors showed that the behavior of wooden frames under consideration could be represented by a combination of link and truss elements. The maximum response of a wooden frame system under three earthquakes showed a safe behavior for a potential earthquake.

Performance of Wood-Frame Wall with Thin ECC Shear Panel

The study evaluates an alternative to traditional wood-framed shear wall construction, an innovative use of a water and seismic damage resistant, wood-concrete-composite (WCC). The WCC design consisted of a thin layer of engineered cementitious composite (ECC) cast in a traditional wood frame. Structural performance and damage sustained during lateral loading and cost were evaluated, and compared to a traditional wood frame with OSB sheathing. Monotonic tests of WCC walls show that the average maximum load was 47.5 kN (10,700 lb) , average elastic shear stiffness was 1.78 kN∕mm (10,200 lb∕in.) and average energy absorbed was 4,810 J (42,600 lb-in.) . Tests show WCC is comparable with or superior to the OSB wall in shear strength and stiffness, energy absorption and ductility. During lateral loading the WCC appeared to sustain less damage than the OSB wall. Panelized construction of the WCC may increase cost but yield benefits such as decreased construction time and greater durability. WCC appears to be a ...

PROPOSAL FOR INSULATOR INFILLED COMPOSITE MUD WALL HOUSES IN MILD CLIMATE REGION AND VERIFICATION REGARDING THERMAL AND MOISTURE PROPERTY

Mud Wall is external wall filling dry mud between structural materials. Mud Wall has been employed as one of the major building components of traditional wood frame houses in Japan. The Mud Wall has proper performances in terms of heat and moisture capacity and fireproof, whereas thermal insulating performance is inferior to general thermal insulation materials such as glass wool, XPS and so on. In this paper, construction method filling an insulation material outside the mud wall layer is proposed for the mud wall houses in mild climate region. The hygrothermal performance of this method was studied by laboratory experiments and numerical simulations in terms of internal condensation issue. Additionally, impacts of the installation of insulation materials on energy conservation and indoor environments were discussed by heat load simulations. The results are as follows; 1) When construction method filling an insulation material in the cavity is adopted, the concealed condensation dose not occur. 2) The annual heating and cooling load of the mud wall house, of which wall is insulated is considerably lower than the existing mud wall house, but improvement of envelope airtightness is necessary to comply with the Japanese next generation energy saving standard.

高減衰型粘弾性ダンパーを用いた梯子状梁による耐震補強効果

In this paper, a laddery beam with high damping viscoelastic dampers is proposed to enhance seismic capacity of traditional timber structures. To make clear the effect of the reinforcement member, shaking table tests were conducted in the Disaster Prevention Research Institute, Kyoto University. As a result, a laddery beam with high damping viscoelastic dampers increased damping ratio and reduced response, compared with those without dampers. The laddery beam with viscoelastic dampers tested was proven to have effectiveness in enhancing seismic performance of traditional wooden frames during earthquakes.

On the thermal and ventilation performance of composite walls

Thermal and ventilation performance is studied in composite walls of traditional wood frame single houses. Equations for heat transfer by conduction, natural convection and radiation are solved using analytical–numerical method. For a standard composite wall, parameters controlling thermal and ventilation performance of composite walls, i.e. the channel width and its surface emissivities are varied and their effect on the overall performance is evaluated. It is found that both the channel width and the emissivity of its surfaces play important roles. There is no optimum width to minimize the heat transfer or to maximize the humidity transport. Compared to standard practice, increased width and employing low emissivity films on channel surfaces may improve thermal performance and humidity evacuation capacity of composite walls.

Structural mechanism of traditional wooden frames by dynamic and static tests

This paper deals with the structural mechanism of traditional wood frames to evaluate the seismic performance of wooden buildings like Japanese temples. The outline of shaking table tests and static tests using several scale models is described and typical experimental results are discussed. From experiments, it is found that the horizontal restoring force of wooden frame without walls depends mainly on the bending moment resistance from tie beams and the restoring force due to column rocking. The equilibrium relationship between the total restoring force and all the bending moments involved is established and verified. Using this equilibrium relationship, it is possible to evaluate the restoring force due to column rocking. The restoring force due to column rocking is the major part of the total restoring force when the frame deformation is small. The bending moments from tie beams become dominant as the deformation increases. The traditional wooden frame has the large flexibility and deformability. It is essential to take advantage of the structural mechanisms found from this study in the seismic and enhancement design of traditional wooden buildings. Copyright © 2005 John Wiley & Sons, Ltd.

Joint characteristics of traditional Chinese wooden frames

The wooden frames of the remains of traditional Chinese architecture were built up using plug-slot type of beam-to-column connections without using any metal nails or bolts. One type of these connections commonly found in primary frames has been studied. Three different types of artificially degraded connections that imitate those deteriorated conditions naturally were investigated experimentally. The behaviour of these connections is found to be semirigid. They can be simulated by a three-parameter connection model. The effects of semirigid connections on frames were also studied through tests and the second-order elastic analysis by the Newton-Raphson method. It is shown that the behaviour of the frame is dominated by the characteristics of the connections. The proposed numerical method can accurately predict the response of the partially restrained wooden frame.