Language：Japanese   Publisher：Architectural Institute of Japan  

In this paper, we first conduct experiments on the prestressed column-beam joints to confirm the differences in historical characteristics and damage properties with and without LSB. Next, the strains acting on the compression edges are compared, and the effect of the LSB reinforcement on the embedment of the column face is confirmed. Finally, static push-over analysis is performed on the column-beam joints to confirm the process of damage in the column-beam joints with and without LSBs.

DOI： 10.3130/aijt.30.662

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Language：Japanese   Publisher：Architectural Institute of Japan  

Uplift load tests were carried out using two types of unit test specimens that reproduced timber roof frame. From the test using the unit test specimen of the rafter joint, it was confirmed that the method based on the simple beam model in the usual design gives the same result as this result. From the test using unit test specimens that reflect the part of roof frame, the authors tried to understand the damage process progress of the entire roof frame and to calculate the strength of the roof frame, and then compared it with the wind load.

DOI： 10.3130/aijt.30.29

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In this paper, the bearing strength, embedment stiffness, joint strength, and joint stiffness are confirmed through experiments on load angles in the fiber direction, perpendicular to the fiber direction, and in the brace direction, and a mechanical model that takes into account load angles applicable to the joint between braces and columns is validated.

DOI： 10.3130/aijt.30.124

DOI： 10.3130/aijs.89.1274_references_DOI_RsXlfHsXy5JU7oCkL7XJuelf4n8

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This paper proposes a new type of brace with elastoplasticity in tension. The brace is made of laminated wood with a hole in the center and a steel bar through the hole. Prestress force is applied to the brace. The brace absorbs earthquake energy in tension and maintain rigidity in compression in the case of large earthquake. And, the brace avoids brittle failure against tensile force. We confirmed the hysteresis characteristics of the brace by experiments, decided material, size and detail. And then we discuss the mechanics of buckling and compensating effects.

DOI： 10.3130/aijt.29.1290

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Displacement mode including torsion when subjected to major earthquake is clearly related to strength balance of each frame while elastic torsional vibration is characterized by stiffness balance. In the previous research, we presented a displacement mode prediction method especially focusing on single-story timber structure having large strength eccentricity. The method is improved by taking the effect of plasticity of transverse walls and bi-axial input motion into account. Finally, necessary additional strength for seismic design of torsionally coupled structure is calculated and is related to eccentricity index. The accuracy of the evaluation method is demonstrated via numerous time history analyses.

DOI： 10.3130/aijs.88.974

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Language：Japanese   Publisher：Architectural Institute of Japan  

In order to realize high-rise wood building, structural design of column base joint is one of the most difficult issues. Generally, failure of timber member, which brittlely fractures, should be prevented. M-N interaction relation is a useful tool to understand the structural characteristic in a practical design. In this paper, M-N interaction relation of base joint of glulam column and CLT wall was investigated by conducting full-scale experiment and numerical analysis using multiple-spring model. It was found that bearing strength of timber is a key parameter to determine the accuracy of the simulation under high intensity of compression force.

DOI： 10.3130/aijt.28.161

DOI： 10.3130/aijs.89.1397_references_DOI_WLIOxfWZ88tN9EDevhCp4b2yE4Q

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Fatigue behavior of glulam moment resisting joint subjected to repeated cyclic loading has not been well clarified. In addition, the accuracy of conventional design formulae for rotational stiffness and yield/ultimate moment should be discussed especially related to the method to obtain material properties. In this research, repeated cyclic loading tests were conducted for drift pined joints with insert-steel gusset plate and tensile-bolted joint. Deterioration of strength and energy dissipation is focused on. The dependency of the performance on the material properties is also investigated through sensitivity analysis.

DOI： 10.3130/aijt.28.167

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This study focuses on the effect of hanging wall and transverse wall associated with CLT shear wall on the mechanical behavior. While structural analysis model for CLT constructions is introduced in the current design manual, how the above members contribute to the shear capacity is not well-understood. In this paper, static lateral loading tests for single-story frame structure with hanging wall and single-wall connected to transverse wall were conducted. The test results were analyzed using simplified model, and the effect of the stiffness/strength balance of each member was discussed.

DOI： 10.3130/aijjse.68b.0_9

DOI： 10.3130/aijs.88.1665_references_DOI_DKEjEnzbIlXMQDYxYiIqL4Hz6MJ

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It is difficult to construct a rigid frame structure without seismic walls and bracing because of the difficulty in ensuring the strength and rigidity of the joints. In the previous paper, dog bone timber-steel hybrid connections, which consist of a dog bone part and a timber-steel hybrid connection that transfers the bending moment of the laminated timber beam to the steel, is proposed. The proposed connection has enabled the realization of a structure with sufficient strength, stiffness and toughness, but the deformation capacity of the connection has not been studied for another cross-sectional dimensions. In this study, based on the previous evaluation equations, an analytical method to derive the history of the M-q relationship by increasing the angle q of the core of the laminated wood to the H-shaped steel of the wood-steel joint, taking the shear force and a single neutral axis calculation were performed to obtain the rotational stiffness Kw, the yielding bending moment My, and the ultimate bending moment Mu of the timber-steel hybrid connection. The validity of the shear force evaluation method and the effect of shear force on the hysteresis properties of the timber-steel hybrid connection are discussed. Four different test specimens (MD600, MD360, CD360 and MS360) are fabricated for the proposed connection with both flanges fixed by lag screws to increase the stiffness and strength of the wood-steel joints. The MD600 is 600 mm height of glued wood and has two bodies with monotonic loading, and the MD360 is 360 mm height of glued wood and has two bodies with monotonic loading. The CD360 is 360 mm height of glued wood and has three bodies with cyclic loading. The MS360 is strength tests of timber-steel hybrid connections, which is 360 mm height in glued wood and has three bodies with monotonic loading. From the joint bending tests, the hysteresis properties and plastic deformation capacity of the proposed connections with dog bone are verified, while the stiffness and holding strength of the timber-steel hybrid connection are verified. As results, the following conclusions are obtained:

1) In the joint bending tests, it was confirmed that the dog-bone part plasticized while wood part is in elastic range for all the test specimens with dog-bones (MD600, MD360, CD360), and that the dog-bone portion was stable and had an excellent plastic deformation capacity exceeding the plasticity ratio of 5. In the MS360 test case, the strength of the wood joint was superior to that of the dog-bone in both stiffness and flexural strength.

2) A new evaluation method that takes into account the shear forces on the wooden joints is proposed and it is confirmed that the proposed method can roughly reproduce the hysteresis properties of the joints. It was confirmed that the proposed method was able to simulate the historical properties of the joints in general, although the effect of shear forces was not so great and the flexural strength of the joints could be reduced by shear forces.

DOI： 10.3130/aijs.86.1224

DOI： 10.3130/aijs.87.1059_references_DOI_KwOd4MGrtinfrfccOWS0ezmKoMj

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In order to investigate the structural performance of the CLT-S hybrid structure with several types of CLT-S connections to improve the hysteresis behavior, experiments of CLT-S hybrid structure frame were conducted. In the new CLT-S connections, the reduced section parts of inserted steel plate restrained for buckling provide improved behavior against cyclic axial forces due to bending moment in CLT panels. From the experiment result, it was found that the new CLT-S connections improve hysteretic property of the frame and energy dissipation efficiency compared to the existing connections.

DOI： 10.3130/aijt.27.213

DOI： 10.3130/aijs.86.1430_references_DOI_5Vs2k5tVuPmqzOCDi7fEXIR6Nb6

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Seismic performance of timber shear walls is generally confirmed through experiment which is provided in the standard. However, the strength and deformation capacities are clearly related to the loading protocol, and such a fatigue behavior is not well-understood so far. In this paper, plywood sheathing wall having 12mm thickness of plywood is tested, and the fatigue behaviors coming up on force-deformation relation and equivalent damping ratio are evaluated.

DOI： 10.3130/aijt.27.202

DOI： 10.3130/aijt.28.167_references_DOI_HgNsgXkshFOa8xzIHyqMvf8eZpF

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Publishing type：Research paper (scientific journal)   Publisher：Wiley  

DOI： 10.1002/2475-8876.12178

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In recent years, utilization of timber-based materials for low-rise non-residential buildings has been actively promoted for environmental considerations, advances in timber design, and the development and support of new laws. However, compared with other structural materials, it is difficult to secure the rigidity and strength of joints in timber-based structures, so additional seismic elements such as shear walls and braces are typically required. Therefore, in this study, a moment frame without the need for such seismic elements was developed. The proposed frame is a hybrid structure that uses steel for the columns and wood materials for the beams, whilst ensuring good overall toughness. A timber-steel hybrid joint (where the timber and H-shaped steel are connected by lag screws and a steel dog bone) is used. The dog bone at the ends of the beam bends at an early stage to avoid damage to the timber. This is expected to improve seismic energy absorption performance comparable to that of a steel rigid joint at the beam ends.

 The fracture behavior and mechanical properties were verified through cyclic bending tests of 1:2 scale partial specimens of the proposed joint. Subsequently, equations for evaluating the rotational stiffness and strength of the joint were proposed. The results of the experiment were reproduced using the obtained values from the equations. Finally, detailed example of a timber-steel frame model and a steel frame model were designed by using the joint rotational stiffness obtained from the experiments. Nonlinear response history analysis was undertaken based on the Ai distribution and artificially generated seismic waves (BCJ-L1 and L2). The seismic performance comparison of the two models was performed using time-history analysis, and the feasibility of the timber-steel hybrid structure building was verified.

 The following shows the findings and results obtained in this study:

 1) In the testing of the proposed timber-steel hybrid beam-to-column joint specimens, the dog bones yielded before the laminated timber joint in all tests, and a stable elasto-plastic bending moment-rotation angle relationship was obtained. While, it was confirmed that slip failure may occur depending on the lap length and the presence or absence of wedges.

 2) The proposed equations for evaluating the rotational stiffness of bonded timber joints and dog bones gives an error of 20% compared to the experimental values. The behavior of the non-linear rotating spring-loaded wire rod model with the estimated value of rotational stiffness showed reasonable agreement with the experimental results.

 3) In the test specimen with a wedge and a wrap length, the theoretical maximum strength of the steel lap was higher than the experimental maximum strength of the dog bone. The experimental results showed that the laminated timber was almost intact, and the validity of the yield strength evaluation formula was confirmed.

 4) It was confirmed that the timber-steel frame model can be designed with a smaller floor weight and stiffness in earthquake design than the steel frame model, and the timber-steel frame model could suppress the maximum response inter-story drift angle in the time history response analysis than the steel frame model.

DOI： 10.3130/aijs.85.945

DOI： 10.3130/aijs.86.1224_references_DOI_PbNPwdPAaaT9uK3gpYPDJigDhnw

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Techniques for large wooden constructions are actively developed for the purpose of reduction of environmental load. One of the solutions for fire and seismic resistance is composite structure, which utilizes different structures like steel or concrete. Wooden structure laterally connected to different structure is discussed, which is called "wooden horizontal hybrid structure". Since it involves stiff cores, most of seismic force acting on wooden parts is sustained by the cores, and wide open space with less shear walls is realized. However, such force transmission complicates the displacement mode as well as the stress distribution in the structure. The authors have proposed dynamics continuous model of horizontal hybrid structure assuming that core part is infinitely-rigid. Although the model can simulate displacement mode of horizontal hybrid structure having various arrangement of shear walls, the structure is assumed to be linearly elastic. While allowable strength design is conducted using elastic model, wooden structures generally have non-linearity even in small deformation. The equivalent stiffness is required to be determined depending on the target deformation. Horizontal hybrid structure, however, shows complicated displacement mode, and it makes it difficult to define deformation and the corresponding equivalent stiffness of each element. Therefore applicability of equivalent linear model is discussed by comparison of analysis result with test result, and simplified evaluation of member force is addressed.

 In this research, prediction by the proposed method is compared to test results conducted by the authors⁹⁾. The referred shake table test on one third scaled model of wooden horizontal hybrid structure is introduced. One side of the specimen is laterally connected to steel jig which represents stiff core. The specimen is 3-story 3-span wooden frame with shear walls. Uni-directional input motions with various intensity are applied to the specimen. Three specimens were tested and the parameters were wall arrangement and nail interval of floor diaphragm which characterizes the stiffness and the strength. The followings are findings of this research.

 1) The prediction method of displacement mode which the authors had proposed was applied to the specimens. Since non-uniform stiffness balance of each element was observed, the balance could be idealized to fit the assumption of the dynamics model. It showed close agreement with test result.

 2) Although stiffness balance of each element was changed according to earthquake intensity, displacement mode and the corresponding equivalent mass ratio were relatively stable. It insists that the existence of core is likely to prevent concentration of deformation on particular element.

 3) 30 to 50% of seismic force acting on wooden part was transmitted to core part through floor diaphragm. No. 2 having stiffer floor diaphragm showed the higher ratio compared to the other specimens. They corresponded to predicted values with acceptable accuracy.

 4) Connection moment between wooden part and core part could be conservatively evaluated using tensile force of bolt and assumed stress condition.

 5) The ratios of connection moment to connection shear force, which represents equivalent floor length, could be conservatively evaluated by assuming triangular distribution.

 6) Based on findings 3), 4) and 5), connection moment between wooden part and core part which is obtained as connection shear force multiplied by equivalent floor length gives tensile force of bolt with some safety margin.

DOI： 10.3130/aijs.85.241

DOI： 10.3130/aijt.28.1195_references_DOI_3cO0cBU1gLUMUwlTaPbJclwsaEe

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Publishing type：Research paper (scientific journal)  

DOI： 10.1016/j.engstruct.2020.110491

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DOI： 10.1016/j.engstruct.2018.12.085

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In our previous paper, the rotational stiffness and the flexural strength of the timber-steel hybrid connections for the lattice shell roofs were clarified by static experiments and the effects on the buckling behavior of the entire roof were revealed. In this paper, we examine the influence of the rotational stiffness at connections on natural oscillation characteristics and earthquake response characteristics of the roofs with supporting substructures. Also, the accuracy of the response spectrum evaluation using CQC method and the evaluation with the equivalent static earthquake load are verified, followed by the simplified evaluation method proposal for the effect of rotational stiffness at connections.<br> As in the past researches, we study with the steps using roof models without supporting substructures then models with substructures. The roofs are categorized as single-layered lattice roofs and double-layered lattice roofs with depth-span ratio being 1/60, where the rotational springs obtained in the previous experiment were incorporated at the both ends. First, we investigate the influence of connection stiffness on the seismic response characteristics of the roof model, comparing the response spectrum method with the time history response analysis to verify the accuracy of the response spectrum method. Here, the applicability of the equivalent static load using response amplification factors proposed by the past researches are also verified. Next, a model with a supporting substructures were set and the earthquake response characteristics were verified. The influence of the rigidity of the supporting frame on the earthquake response was analyzed, and accuracy of the equivalent static load was verified. Here, we also analyze the influence of the rotational stiffness of the connections as well as the roof model. From these investigations, it was confirmed that there was no significant influence of the connection stiffness on earthquake response characteristics were observed, if the natural periods of principal modes are correctly evaluated. Therefore, it was considered that the influence of the rotational stiffness at the connections on the earthquake response can be represented by the natural period ratio R_T. It was also found that the natural period of the antisymmetric mode including connection stiffness can be expresses as the function of normalized rotational stiffness κ, and easily evaluated from the eigenvalue analysis with rigid connections.<br> From above studies the following knowledge was obtained.<br> 1) In the roof models with the rotational stiffness at connections, the influence of the rotational stiffness on the vibration characteristic is not significant where normalized rotational stiffness κ >7..<br> 2) Seismic response of a lattice shell roofs with the connection of normalized rotational stiffness κ = 3 ~ ∞ (rigid) is can be well evaluated if the correct roof natural period with the rotational stiffness at connections are obtained and used. It was confirmed that the accuracies of the equivalent static loads with amplification factors are almost the same as the those with rigid connections.<br> 3) The effects of connection rotational stiffness on the principal natural period of the roofs can be expressed as a function of κ. Therefore, the natural period including the connection stiffness for equivalent load estimation can be easily obtained by multiplying the proposed formula to the natural period of the roof model with rigid connections. The accuracy of the proposed method is verified, and confirmed to provide equivalent accuracies.

DOI： 10.3130/aijs.84.51

DOI： 10.3130/aijs.87.1059_references_DOI_DFzkPtQ3raJtEUobvUlqVtniRFh

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Conventional test program for timber shear walls in Japan uses a loading protocol consisting of monotonic loading following reverse cyclic loading up to 1/50rad. While repeated cyclic loading is thought to decrease force and deformation capacity due to the fatigue behavior, specimens based on the conventional test program might not sustain enough cycles at large deformation range. Although timber shear walls had better have large deformation capacity, it is not always empirically confirmed. Recently, buildings are required to protect not only the safety but the property after a major earthquake, and passive control techniques for timber structures have been developed in order to enhance the seismic performance. Therefore, evaluation of timber shear walls' fatigue behavior have become an important issue.

 Several experiment-based studies on timber shear walls' fatigue behavior can be found, and some of them have proposed hysteresis model for time history analysis. However, time history analysis are rarely used for seismic design of timber detached houses owing to time and effort. Response spectrum method, which is approximated calculation method for maximum earthquake response, is alternate seismic design rule in order to specify the performance. In response spectrum method, characteristic of building is determined by two parameters: equivalent stiffness and equivalent damping ratio. Fatigue behavior should be taken into account as deterioration of the two parameters.

 In this study, the final goal is to develop a response spectrum method considering fatigue behavior of timber shear walls. Part 1 deals with evaluation of strength and energy dissipation of two typical timber shear walls subjected to various deformation history. Chapter 2 introduces static loading tests. Various loading protocol were applied. Chapter 3 introduces shaking table tests. Two types of earthquake motions having same spectrum shape and different duration time were applied. Chapter 4 introduces evaluation formulae for strength and equivalent damping ratio. The followings are findings of this research.

 1) Envelope curve of force-deformation angle relation has dependency on loading protocol. The envelope curve in monotonic loading is the upper limit, and the others go down as the number of cycles becomes large.

 2) Plywood type shear walls are vulnerable to repeated loading rather than brace type shear walls, which is likely to be related to the failure mode. As for plywood type shear walls, when the number of cycles was small like monotonic loading, failure mode of nail joint was punching out. However, when the number of cycles was large, nail joint was fractured by bending.

 3) When two earthquakes having the same response spectrum shape and different duration time were repeatedly applied, the one having longer duration time rapidly brought deformation increase. It is likely to be related to fatigue behavior owing to repeated loading similar to the above finding 1).

 4) Both brace type and plywood type specimens kept seismic performance against repeated earthquake motions if the maximum deformation response was less than one third of the ultimate deformation.

 5) Evaluation formulae for strength and equivalent damping ratio considering fatigue behavior were proposed. The formula for strength has a unique parameter controlling damage effect when the deformation amplitude is expanded. The formula for equivalent damping ratio is empirically derived based on the fact that equivalent damping ratio has strong dependency on the already experienced maximum deformation rather than the number of cycles. They showed acceptable agreement with results of static random loading tests and shaking table tests.

DOI： 10.3130/aijs.84.1443

DOI： 10.1002/2475-8876.12178

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Wooden roof frame is required to have angle braces and intertruss bracings based on the current specification code. In the past natural disasters except for strong wind by typhoons, wooden roof frames have rarely suffered severe damages. The current code has been thought to work well. However, traditional-type wooden roof frame does not satisfy the current code. In addition, the roof frame is boarding diaphragm consisting of narrow boards fastened by nails, which is thought to have low shear stiffness and strength unlike plywood sheathing floor diaphragm.

 A roof frame works as horizontal diaphragm transmitting lateral force to shear walls. In the current allowable stress design, stress distribution of a floor diaphragm is calculated using continuous shear beam. The allowable strength is determined by referring to test results of elements such as roof frame covered by wooden boards and beam frame with angle braces. Since the design method is originally applied to modern wooden roof frame, the applicability to traditional-type wooden roof frame should be investigated.

 In this paper, shear performance of gable roof, which is one of the typical roof systems, subjected to lateral force in the longitudinal direction is discussed. Although previous studies often consider pure shear condition, equally distributed forces with two specific boundary conditions are applied to roof frame in order to simulate earthquake force or wind force. Following the full-scale experiment, the behavior is simulated by two-dimensional framing analysis model whose characteristics is determined by referring to results of element tests. Parameter study with various specifications of each element is also conducted, and the effect of the stiffness balance on the shear behavior of roof frame is investigated. Finally, the framing model is converted to simplified model which is capable of expressing mathematical relation of each parameter.

 The followings are findings of this research.

 1) In cantilevered roof frame, shear force-deformation angle relations of roof frame and beam frame could be simply added.

 2) In roof frame specimen, shear force was sustained by roof frame while moment was sustained by beam frame. It is likely to be assured by rotational resistance of transverse walls.

 3) Average shear stress along the span controls the behavior of roof frame, and it is reasonable to suppose that the average shear stress should be checked in each half span divided by ridge beam. Actually, flexural resistance of beam frame had an effect of making shear deformation in the roof frame more equal. However, it is difficult to be assured when connections exist in the tie beams.

 4) Two-dimensional framing analysis model was constructed based on results of element tests, and it gave close agreement with test results.

 5) Parameter studies of framing analyses showed that replacement of nuki with brace in vertical frame had little effect on performance of roof frame due to relatively large contribution of moment resistance by tenon connections.

 6) Simplified model derived from framing model could give mathematical relation of each parameter. It can provide simple formulae of whole behavior with less effort.

 Although the effect of in-plane shear stiffness on dynamic behavior of a building is not mentioned in this paper, the above 3) insists that 2-span dynamic model, which has been proposed by the authors^14)-16), can be utilized. It will be discussed in the future.

DOI： 10.3130/aijs.84.1453

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The authors have proposed effective steel connections achieving high bending stiffness and strength for timber grid-shell structures in the previous research. They are composed of joints with T-section or H-section brackets connected to glued laminated timber section members through lag-screw bolts at flanges, their bending stiffness and strength have proved to be much higher than the ones of conventional connections. However, their performance against negative out-of-plane and in-plane directions which affect the shell buckling strength are not clear yet. In this research, the bending performance of the proposed connections against negative out-of-plane and in-plane directions are confirmed through real-size mock-up tests. They are compared to the performance against positive out-of-plane. Formulas for evaluating the stiffness and strength of the connections against these directions are proposed, and their validity are verified by comparing with the test results.

 First, detailed analysis methods evaluating negative out-of-plane and in-plane stiffness and strength are constructed based on equilibrium of forces between steel bracket and timber beam and their compatibility condition. Next, approximating the process of neutral axis iteration, simplified formulas are demonstrated. Also, assuming the neutral axis at the center of the connections, further simplified equations for stiffness and strength are proposed. Then, real-sized mock-up specimens for the proposed connections are constructed, and simple bending tests in negative out-of-plane and in-plane directions are carried out. Their bending moment – rotational angle relationships are compared with the proposed formulas and their validity is confirmed.

 As results, the following conclusions are obtained.

 1) TB300 (T-section bracket with 300mm length) exhibited higher bending stiffness and strength in negative out-of-plane direction than those in positive direction. TB400 (T-section with 400mm length) exhibited lower bending stiffness but higher strength in negative out-of-plane direction.

 2) For in-plane bending tests, all specimens showed much lower rotational stiffness and strength than those in out-of-plane directions. Those of TB440 and HB (H-section bracket) exhibited nearly twice than those of TB300, which is caused by the effects of shear resistance of lag-screw bolts.

 3) Comparing with the test results, the proposed detailed analysis methods well evaluate bending moment – rotational angle relationship, while the ultimate strengths are a little overestimated. In addition, proposed simple formulas estimate the test results in safer sides, and considered as valid for practical use.

 4) TB300 has higher rotational stiffness and strength in negative out-of-plane direction than the ones in positive out-of-plane direction. However, TB440 has lower rotational stiffness and higher strength in negative out-of-plane direction than the ones in positive out-of-plane direction. As for in-plane rotational stiffness and strength, they are lower than the ones in out-of-plane direction. Therefore, the difference of rotational stiffness in out-of-plane/in-plane directions has to be considered when evaluating buckling strength of timber grid-shell structures.

DOI： 10.3130/aijs.84.831

DOI： 10.3130/aijs.86.1224_references_DOI_G6axmuVYv9vNxrpdLzDWB1QC92h

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The authors have proposed effective steel connections achieving high bending stiffness and strength for timber grid-shell structures, and confirmed their performances through real size mock-up tests. In this research, reflecting the test results, the buckling strength of 24m-span timber grid-shell with and without diagonal bracing roofs are discussed. Their theoretical buckling strength including the rotational stiffness at connections are derived using continuum shell analogy, and compared with the results of discrete FEM analyses. Finally, the reduction factor equations of buckling strength as the functions of in-plane / out-of-plane bending stiffness ratio and two directional rotational stiffness are proposed, followed by confirming their validity.

 Dimensions of the studied single-layer timber latticed grid-shell are assumed to be 24 m × 24 m. The discrete FEM analysis models as Fig. 3, 4 are constructed using the fiber models with two-directional rotational springs at connections. The results of the real size mock-up bending tests are reproduced with the constructed FEM model. They showed good agreement and the validity of the FEM models are confirmed. Using the constructed FEM model, the grid-shell roof with and without diagonal bracings, with various proportions of timber sections, and various in-plane / out-of-plane rotational stiffness are constructed and their elastic buckling strength including geometrical nonlinearity are investigated. Generally, the bending stiffness of timber members and rotational stiffness of the connections are lower in in-plane directions (along z-axis) than in out-plane directions (along x-axis) in the test results. As the results of analyses, the buckling strength of the roof decreases along the stiffness of in-plane stiffness of the timber member (I_z) decreases, and also the rotational stiffness of the connections along in-plane (K_θz) and out-of-plane (K_θy) direction decreases. Therefore, estimating the effects of these stiffness is essential for evaluating the buckling strength of the grid-shell roof.

 To derive the equations for estimating the effects of these stiffness, continuum shell analogy is applied. The classic shell buckling theories are developed including the effects of the in-plane member bending stiffness and in-plane / out-of-plane rotational stiffness of the connections. The derived equations are simplified and the reduction factor equations of buckling strength are proposed as the functions of I_z / I_y and K_θz / K_θy. The obtained conclusions are summarized as follows.

 (1) The buckling strength derived from the continuum shell analogy gives values agreeing well with FEM analyses in grid-shell roofs without diagonal bracing. While those with diagonal bracing gives higher values than FEM analyses. This is because the shear stiffness of the roof panels is underestimated for neglecting axial deformations of timber chords.

 (2) The proposed reduction factor equations are confirmed to give reasonable values for grid-shell roofs without diagonal bracing and low-rise grid-shell roofs with diagonal bracing.

DOI： 10.3130/aijs.84.1081

DOI： 10.3130/aijs.87.1059_references_DOI_IVCZcUwtb2iqwHIA2vQbfG183Vi

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DOI： 10.1016/j.engstruct.2018.02.061

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Language：Japanese   Publisher：Architectural Institute of Japan  

Construction of wooden buildings utilizing CLT has become active in Japan. Although a design manual for CLT buildings was published in 2016, it does not cover a connection using drift pins and insert-steel gusset plate which are one of the frequently used connection types. Nakashima et al. showed that the performance of the connection could be simulated by conducting nonlinear analysis of rigid-body-spring model representing a drift pin on CLT. However, simple formulae to calculate shear stiffness and shear strength of the connection is required in practical design. In this paper, the connection with different strength grade and layer constitution of CLT were tested. In addition, the effect of the location of un-bonded edge-jointing, grain direction and the number of drift pins and their layout were also discussed. Finally, calculation formulae of shear stiffness and shear strength of the connection were proposed.<br> Chapter2 introduces the connection tests and the test results. A steel plate was inserted into CLT and they were jointed with drift pins. The connection was subjected to static monotonic loading. Parameters of specimens were strength grade and layer constitution of CLT, the location of un-bonded edge-jointing, grain direction and the number of drift pins and their layout. Total forty types were tested, each of which had six specimens. The variability of the shear stiffness was large while the one of the shear strength was small. The effect of the location of un-bonded edge-jointing on the shear stiffness and the shear strength was not significant. 3-layer 3-ply specimens using two drift pins tended to fracture by split failure between the two drift pins as compared with 5-layer 5-ply specimens. In addition, the shear stiffness and the shear strength of some specimens having two drift pins did not reach twice of the ones having one drift pin. It was more significant in the shear stiffness, and the corresponding coefficient of variations were also increased.<br> Chapter3 introduces evaluation of shear stiffness of the connection based on theory of a beam on elastic foundation. In order to obtain the strict solution, different deflection curves have to be defined at each lamina and they are combined based on the boundary conditions because the foundation constants are different at each lamina. Therefore simplified mechanical model are proposed, which gives practical formula of shear stiffness, instead of solving complicated strict model.<br> Chapter4 introduces evaluation of shear strength of the connection based on European yield theory. Since a lot of yield modes can be assumed, the candidates of the yield modes are reduced by considering possible range of parameters and the corresponding formula is simplified.<br> Chapter5 introduces comparison between test results and calculation results. Yield strength and ultimate strength were evaluated by Nakashima's method as well as by proposed method. The proposed method could predict test results with good accuracy.

DOI： 10.3130/aijs.83.1811

DOI： 10.3130/aijt.30.106_references_DOI_HRIrDxv6EwS7jbDOsJO6g4KxMmd

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In recent years, timber structures are popularly applied for lattice shell roofs to create a long span space due to lightweight and aesthetics. This research proposes several types of steel connections for timber lattice shells improving structural performance and architectural appearance. The out-of-plane flexural strength and rotational stiffness of the proposed connections are examined by full-scale experiments. Based on the experimental results, the seismic performance of timber lattice shell roofs using proposed connections is investigated.<br> Dimensions of a single-layer timber lattice shell are assumed to be 24 m × 24 m × 3.2 m. The five types of connections are proposed for this single layer lattice shell as shown in Fig. 2. Rectangular laminated timber members are fixed to tee or wide flange section with lag screws. These connections basically resist to out-of-plane bending moment by the pull-out force of lag screws and bearing force between the timber members and steel connections as shown in Fig. 3. Tests on three specimens for each type of connection were carried out to confirm the rotational stiffness, flexural strength and fracture mode with respect to out-of-plane bending.<br> Numerical simulations of a single-layered timber lattice shells illustrated in Figs. 7 and 8 using proposed five types of connections were conducted to investigate their buckling loads. The strength reduction factor for elastic buckling load against linear buckling load α₀ was estimated approximately as 0.9. Fig. 10 shows that the strength reduction factor due to connection stiffness β(κ), stipulated in AIJ Recommendation for Design of Latticed Shell Roof Structures (AIJ Rec for Shell), and found to be less than the calculated values in numerical simulations with evaluated connection stiffness in the tests. The effect of timber shear stiffness on the strength reduction factor was also investigated. At last, elastic buckling load of timber lattice shells could be estimated multiplying reduction factors α₀ and β(κ) to linear buckling load. The findings are summarized as follows.<br> (1) The maximum flexural strength of the proposed connections ranges 0.34 to 0.87 times the laminated material bending strength M_b, and the normalized rotational stiffness ratio κ (Eq. (56)) ranges from 7.5 to 22. This rotational stiffness ratio values indicate that the proposed connections are categorized as medium stiffness for single layer timber lattice shells.<br> (2) In tee flange connections, the rotational stiffness and flexural strength increase as the wrap length elongates. The wide flange connections exhibited maximum flexural strength, though the rotational stiffness is smaller than other connections with equivalent wrap length,<br> (3) Evaluation formulas to calculate the rotational stiffness and the flexural strength for the proposed connections are provided. The values calculated by the formulas generally correspond to the test results with a safety margin.<br> (4) The knockdown factor β(κ) for the buckling load of timber lattice shells in of each connections range from 0.74 to 0.87, which is applicable for practical design of single-layered timber lattice shell roofs.<br> (5) The elastic buckling load of timber lattice shell roofs with the proposed connections can be evaluated multiplying the reduction factor γ_t , the knockdown factor β(κ) f and the reduction coefficient α₀ which can be assumed 0.9 to the linear buckling load.

DOI： 10.3130/aijs.83.577

DOI： 10.3130/aijs.85.945_references_DOI_PUNxbkMVI9F7Rdzhl1LZ1u0fCZL

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Language：Japanese   Publishing type：Research paper (scientific journal)   Publisher：日本建築学会  

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Other Link： https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-15H02990/

Language：Japanese   Publisher：Architectural Institute of Japan  

Traditional-type boarding floor diaphragm of wooden structures consists of narrow boards fastened by nails and has low shear stiffness unlike plywood sheathing floor diaphragm. It is incapable of achieving so-called rigid floor assumption which is generally assumed in the current seismic design standard. In practical design and seismic diagnosis, when the structure has flexible floor diaphragm, three dimensional framing analysis is required. Therefore, the flexible floor diaphragm is believed to make the dynamic behavior quite complicated and to make the simulation difficult.<br> In this paper, simplified evaluation method of basic dynamic properties such as natural circular frequency and mode shape for single-story wooden structures is proposed. A theory of 2x2-span flexible floor dynamics model which the authors has proposed is developed, and useful indexes indicating the effect on the dynamic properties are derived in the process. Although eigen value analysis requires matrix operation and numerical solver to obtain natural circular frequency and mode shape, the proposed method can provide them only with the four arithmetic operations of the indexes. The accuracy of the method is confirmed by comparison with numerical analysis solutions. In addition, applicability of conventional method such as sparsely discretized model (i.e. lumped mass model) and static pushover analysis is also investigated.<br> The followings are findings of this research.<br> 1) Dynamic properties such as natural circular frequency and mode shape were estimated using the ones of simplified models with smaller number of degrees of freedom: reverse symmetric shear model and symmetric shear model. Regarding mode shape, another model might be included, and the accuracy was improved in particular cases.<br> 2) Dynamic properties of the simplified models stated above could be calculated using a controlling index.<br> 3) Lumped mass model was likely to give smaller natural circular frequency compared to strict solutions due to neglect of flexural stiffness of floor diaphragm and to sparsely discretized mass.<br> 4) Accuracy of static analysis for natural circular frequency(i.e. initial stiffness) was variable. Mode shape was well predicted except for particular cases.<br> 5) Natural circular frequency and mode shape of whole structure could be determined by the two controlling indexes, and the contours were drawn. If the criteria of dynamic properties are set, the acceptable range of the two indexes is clearly found out from the contours.<br> By considering mode shape given by the proposed method as acceleration distribution, it can be applied to static force distribution in horizontal direction when static push-over analysis is conducted. As a future plan, two-story structures and inelastic behavior derived from plasticity of shear walls will be addressed.

DOI： 10.3130/aijs.83.1833

DOI： 10.3130/aijt.27.1261_references_DOI_Hix2kNdKVMKyU81TQMoBpnMbIB8

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Eccentric arrangement of shear walls leads to torsional vibration, which is one of the reasons for collapses or severe damages of huge number of wooden houses in the past earthquakes. Therefore eccentricity ratio R_e is defined in Japanese Building Standard Law to confirm the adequacy of shear walls' arrangement. Although R_e is calculated in each story and in each direction, it does not consider interaction between different stories. For example, even though a story does not have any eccentricity, torsional response can be excited by another story with eccentricity. Such a phenomenon is not simulated by R_e.<br> Most of Japanese wooden houses are two-story, and some of them have setback. In addition, the lower story typically has larger eccentricity and the upper story has less eccentricity. The torsional interaction as stated above is likely to affect the displacement mode of wooden houses.<br> In this paper, prediction method of displacement mode for two-story wooden structure with eccentricity is proposed, and the applicability is discussed. When a single-story structure is considered, dynamic displacement mode including torsional response is approximated by our previous method⁷⁾ instead of solving eigen value equation. Therefore displacement mode in each story without interaction is firstly evaluated, and the interaction effect is added to it. The key idea is based on "Force-Dependent Ritz Vector" which gives simple formulae of practical use.<br> The structure is assumed to be linearly elastic and to have uni-axial eccentricity and infinitely-rigid floor diaphragm. Uni-directional earthquake input is considered. The followings are findings of this paper.<br> 1) Prediction method of torsional displacement mode considering interaction between upper and lower stories was proposed, and the accuracy was confirmed by comparison with numerical analyses.<br> 2) While torsion in lower story is not so affected by upper story, the one in upper story is clearly affected by lower story.<br> 3) A story with eccentricity apparently has less lateral story stiffness compared to the one without eccentricity, resulting in large story drift.<br> 4) If a deference of eccentricity ratios in upper and lower stories exceeds 0.15, an interaction of torsion between upper and lower stories should be considered. If not, it is negligible.<br> In this research, two-story wooden house was focused on as a representative of multi-story building having different length of eccentricities in each story. However, a base isolated building whose superstructure has eccentricity has the same problem, and the proposed method can be applied to such structures.<br> Since this research considers linearly elastic structures with uni-axial eccentricity, issues like non-linearity and bi-axial eccentricity will be investigated in the future research.

DOI： 10.3130/aijs.83.467

DOI： 10.3130/aijs.83.1833_references_DOI_WSYww4fw6gfnrNaqIzjbzwLCeC8

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Publishing type：Research paper (scientific journal)  

DOI： 10.1155/2018/1940706

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DOI： 10.1061/(ASCE)ST.1943-541X.0002115

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Language：Japanese   Publishing type：Research paper (scientific journal)   Publisher：日本建築学会  

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Language：Japanese   Publisher：Architectural Institute of Japan  

Horizontal hybrid structure which involves stiff cores to enhance the seismic and fire resistance is sometimes employed as a
solution of large wood buildings. However, it makes it difficult to evaluate the three-dimensional vibration mode and the
connection force between the two different structures. The authors have proposed dynamics model of horizontal hybrid
structure considering continuous body based on an assumption that shear walls are equally distributed in the plan. In this paper,
the former model is developed to consider various arrangements of shear walls, and new method to predict maximum
displacement mode and member forces is proposed. The accuracy is demonstrated by comparison with numerical analyses, and
they give close agreement.

DOI： 10.3130/aijs.82.555

DOI： 10.3130/aijt.27.1261_references_DOI_9EMPyBCtYMIwEA0GQCKL9bw55Hb

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Small detached wooden houses typically have eccentric arrangement of shear walls, which results in torsional vibration when subjected to earthquake. In addition, flexible floor diaphragm of wooden structures complicates the dynamic behavior. Since eccentricity ratio, which is originally defined in Japanese Building Standard Law, is a simple index to confirm adequacy of arrangement of shear walls, such a complicated behavior is not accurately simulated.<br> In this paper, index of torsion taking dynamic effect and flexibility of floor diaphragm into account is proposed based on dynamics model. In chapter2, structural model and the precondition in this study is stated. Translational behavior is assumed to be dominant rather than rotational behavior. In chapter3, 1x1-span flexible floor model is considered, and the dynamic properties are derived. The particular solution for rigid floor model is also dealt with as a kind of the general solutions for flexible floor model. In chapter4, 2x2-span flexible floor model is considered, and the dynamic properties are derived. In chapter5, eccentricity ratio is developed to address dynamic effect and flexibility of floor diaphragm. The range of application of the method is discussed in appendix.<br> The followings are findings of this research.<br> 1) Modal shape of infinitely-rigid floor model is expressed by a parameter which is defined as "dynamic torsion index". It is the same as the one proposed by Ohami¹²⁾ et al. when the structure has infinitely rigid floor diaphragm. In addition, it is nearly the same as the one proposed by Fujii¹³⁾ when the structure suffers small torsion.<br> 2) The index is theoretically related to modal shape of 1st mode obtained by eigen value analysis. The corresponding natural circular frequency is also estimated with acceptable accuracy.<br> 3) Conventional static analysis, which generally considers mass-proportional lateral load, gives smaller torsion compared to 1st mode shape obtained by eigen value analysis due to so-called dynamic effect.<br> 4) When a floor diaphragm is quite flexible, the structure is modeled by 2DOF system and defined as perfectly-flexible floor model. Dynamic torsion index for perfectly-flexible floor model is also defined similar to the infinitely-rigid floor model.<br> 5) Dynamic properties of general 1x1-span flexible floor model, which is 3DOF system, is obtained by interpolation by the ones of infinitely-rigid floor model and perfectly-flexible floor model.<br> 6) Dynamic properties of 2x2-span flexible floor model, which is 4DOF system, is obtained by interpolation by the ones of reverse symmetric shear model(reduced 2DOF) and symmetric shear model(2DOF). It insists that the effect of flexible floor diaphragm can be separated into the ones related/non-related to torsion.<br> 7) The tendency of the dynamic behavior is compared to eccentricity ratio, and the key parameters to control torsional coupling is pointed out. The dynamic effect is reflected by the radius of gyration in the equivalent elastic radius.<br> As a future plan, inelastic torsional behavior derived from plasticity of shear walls will be addressed.

DOI： 10.3130/aijs.82.1413

DOI： 10.3130/aijs.83.1833_references_DOI_Ou3snjHt3hZtkpV9KH20FKQZkCY

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In the current design code, verification of eccentricity ratio R_e is required, which represents appropriate distribution of shear walls. The limitation of R_e contributes to prevention of torsional vibration. However, damping performance is affected by distribution of dampers in the plan because the energy dissipation of each damper is clearly related to deformation mode of the structure. In this paper, the verification method of appropriate distribution of energy dissipation walls to wooden house is proposed. The accuracy of the method is confirmed by numerical simulations considering various kind of parameters with wide range.

DOI： 10.3130/aijt.22.495

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DOI： 10.3130/aijs.81.291

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DOI： 10.1061/(ASCE)ST.1943-541X.0001405

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DOI： 10.3130/aijs.80.457

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Application of passive dampers to timber structures is increasing with the aim of reducing seismic response including translation and torsion. The structure in such a case possesses the so-called non-proportional damping. In this paper, new system identification method considering non-proportional damping is proposed. Modal shapes including phase differences of each point are evaluated using special technique, which makes real-valued expression possible. Accuracy of the method is confirmed by comparison with shaking table test. It showed close agreement.

DOI： 10.3130/aijt.20.515

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DOI： 10.3130/aijs.79.103

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Other Link： https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-12J09350/

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In this paper, tensile behavior of split wedge joint is examined. Tensile tests for split wedge joint are conducted. Fifty-four specimens are tested, and their parameters are dimension of post, beam, tenon, notch line and wedge and tree species of members. The tensile properties are shown from the experimental results. In addition, evaluation rule for tensile behavior of split wedge joint considering initial bearing stress by wedge is proposed. It is based on the result of embedment test of wooden materials.

DOI： 10.3130/aijt.19.903

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Publishing type：Research paper (scientific journal)  

DOI： 10.3130/aijs.78.1459

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DOI： 10.3130/aijs.78.471

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DOI： 10.3130/aijs.78.2163

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DOI： 10.3130/aijs.78.959

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Publishing type：Research paper (scientific journal)  

DOI： 10.3130/aijs.77.555

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DOI： 10.3130/aijs.77.927

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DOI： 10.3130/aijs.77.45

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DOI： 10.3130/aijs.76.959

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DOI： 10.3130/aijs.76.1109

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DOI： 10.3130/aijs.75.1691

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Seismic response of one-story structure with the significant stiffness eccentricity, developing a torsional mode, is studied in this paper. Viscous damping is added to reduce both the translational and torsional vibration of the structure. The structure in such a case possesses the so-called non-proportional damping, which makes the conventional modal analysis using undamped vibration mode more inaccurate. On the other hand, more accurate method using the complex-valued mode is not easy for practical analysis, and is not very effective to understand dynamic response characteristies of the structure. Hence, this paper proposes a new modal analysis which uses the real-valued mode and yet treats the non-proportional damping effect with a unique correction process. Many cases of non-proportional damping are examined, and the reasonable accuracy of the proposed method is demonstrated through comparison with the other existing methods.

DOI： 10.3130/aijs.74.225

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Language：Japanese   Publisher：日本建築学会  

CiNii Research

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Language：Japanese   Publisher：日本建築学会  

CiNii Research

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Language：Japanese   Publisher：日本建築学会  

CiNii Research

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Language：Japanese   Publisher：日本建築学会  

CiNii Research

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Language：Japanese   Publisher：日本建築学会  

CiNii Research

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Language：Japanese   Publisher：日本建築学会  

CiNii Research

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Language：Japanese   Publisher：日本建築学会  

CiNii Research

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Language：Japanese   Publisher：日本建築学会  

CiNii Research

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Language：Japanese   Publisher：東京 : 旭硝子財団  

CiNii Books

CiNii Research

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Other Link： https://ndlsearch.ndl.go.jp/books/R000000004-I028579872

Language：Japanese   Publisher：日本地震工学会  

identifier:oai:t2r2.star.titech.ac.jp:50338484

CiNii Research

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Language：Japanese   Publisher：日本建築学会  

CiNii Research

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Language：Japanese   Publisher：日本建築学会  

CiNii Research

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Language：Japanese   Publisher：日本建築学会  

CiNii Research

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Language：Japanese   Publisher：日本建築学会  

CiNii Research

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Language：Japanese   Publisher：日本建築学会  

CiNii Research

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Language：Japanese   Publisher：日本建築学会  

CiNii Research

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Language：Japanese   Publisher：日本建築学会  

CiNii Research

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Language：Japanese   Publisher：日本建築学会  

CiNii Research

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Language：Japanese   Publisher：日本建築学会  

CiNii Research

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Language：Japanese   Publisher：東京 : 日本住宅・木材技術センター  

CiNii Books

CiNii Research

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Other Link： https://ndlsearch.ndl.go.jp/books/R000000004-I027198363

Language：Japanese   Publisher：Architectural Institute of Japan  

CiNii Research

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Language：Japanese   Publisher：Architectural Institute of Japan  

CiNii Research

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Language：Japanese   Publisher：Architectural Institute of Japan  

CiNii Research

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Language：Japanese   Publisher：Architectural Institute of Japan  

CiNii Research

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Language：Japanese   Publisher：Architectural Institute of Japan  

CiNii Research

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Language：Japanese   Publisher：Architectural Institute of Japan  

CiNii Research

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Language：Japanese   Publisher：Architectural Institute of Japan  

CiNii Research

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Language：Japanese   Publisher：Architectural Institute of Japan  

CiNii Research

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Language：Japanese   Publisher：日本建築学会  

CiNii Books

CiNii Research

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Language：Japanese   Publisher：日本建築学会  

CiNii Books

CiNii Research

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Language：Japanese   Publisher：Architectural Institute of Japan  

CiNii Research

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Language：Japanese   Publisher：Architectural Institute of Japan  

CiNii Research

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Language：Japanese   Publisher：Architectural Institute of Japan  

CiNii Research

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Language：Japanese   Publisher：Architectural Institute of Japan  

CiNii Research

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Language：Japanese   Publisher：Architectural Institute of Japan  

CiNii Research

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Language：Japanese   Publisher：Architectural Institute of Japan  

CiNii Research

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Language：Japanese   Publisher：日本建築学会  

CiNii Books

CiNii Research

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Language：Japanese   Publisher：日本建築学会  

CiNii Books

CiNii Research

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Language：Japanese  

identifier:oai:t2r2.star.titech.ac.jp:50231623

CiNii Research

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Language：Japanese   Publisher：Architectural Institute of Japan  

CiNii Research

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Language：Japanese   Publisher：Architectural Institute of Japan  

CiNii Research

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Language：Japanese   Publisher：Architectural Institute of Japan  

CiNii Research

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Language：Japanese   Publisher：Architectural Institute of Japan  

CiNii Research

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Language：Japanese   Publisher：日本建築学会  

CiNii Books

CiNii Research

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Language：Japanese   Publisher：日本建築学会  

CiNii Books

CiNii Research

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Language：Japanese  

identifier:oai:t2r2.star.titech.ac.jp:50197159

CiNii Research

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Language：Japanese   Publisher：Architectural Institute of Japan  

CiNii Research

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Language：Japanese   Publisher：Architectural Institute of Japan  

CiNii Research

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Language：Japanese   Publisher：Architectural Institute of Japan  

CiNii Research

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Language：Japanese   Publisher：日本建築学会  

CiNii Books

CiNii Research

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Language：Japanese  

identifier:oai:t2r2.star.titech.ac.jp:50161393

CiNii Research

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Language：Japanese   Publisher：Architectural Institute of Japan  

CiNii Books

CiNii Research

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Language：Japanese   Publisher：Architectural Institute of Japan  

CiNii Books

CiNii Research

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Language：Japanese   Publisher：Architectural Institute of Japan  

CiNii Books

CiNii Research

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Language：Japanese   Publisher：Architectural Institute of Japan  

CiNii Books

CiNii Research

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Language：Japanese   Publisher：Architectural Institute of Japan  

CiNii Books

CiNii Research

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Language：Japanese   Publisher：日本建築学会  

CiNii Books

CiNii Research

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Language：Japanese  

identifier:oai:t2r2.star.titech.ac.jp:50124477

CiNii Research

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Language：Japanese   Publisher：Architectural Institute of Japan  

CiNii Books

CiNii Research

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Language：Japanese   Publisher：Architectural Institute of Japan  

CiNii Books

CiNii Research

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Language：Japanese   Publisher：Architectural Institute of Japan  

CiNii Books

CiNii Research

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Language：Japanese   Publisher：Architectural Institute of Japan  

CiNii Books

CiNii Research

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Language：Japanese  

identifier:oai:t2r2.star.titech.ac.jp:50094581

CiNii Research

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Language：Japanese   Publisher：Architectural Institute of Japan  

CiNii Books

CiNii Research

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Language：Japanese   Publisher：Architectural Institute of Japan  

CiNii Books

CiNii Research

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Language：Japanese   Publisher：Architectural Institute of Japan  

CiNii Books

CiNii Research

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Language：Japanese   Publisher：Architectural Institute of Japan  

CiNii Books

CiNii Research

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Language：Japanese   Publisher：Architectural Institute of Japan  

CiNii Books

CiNii Research

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Language：Japanese   Publisher：Architectural Institute of Japan  

CiNii Books

CiNii Research

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Award type：Award from Japanese society, conference, symposium, etc. 

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Award type：Award from publisher, newspaper, foundation, etc. 

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Award type：Award from Japanese society, conference, symposium, etc. 

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環境負荷低減した大規模木造建築を実現する平面異種混構造の耐震設計法の開発

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Award type：Award from Japanese society, conference, symposium, etc. 

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Award type：Award from international society, conference, symposium, etc. 

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Award type：Award from Japanese society, conference, symposium, etc. 

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