著者
辛 殷美 讃岐 将嗣 青木 ゆい 藤田 香織
出版者
日本建築学会
雑誌
日本建築学会構造系論文集 (ISSN:13404202)
巻号頁・発行日
vol.80, no.711, pp.757-766, 2015 (Released:2015-06-24)
参考文献数
22
被引用文献数
3 3

This study aims to clarify the structural performance of two typical Japanese traditional timber joints used in Kenchoji-temple in Kamakura, Japan. The frame consisting of column and penetrating beam is one of the most important structural elements of traditional wooden structures. More often, there is a connecting joint of the beam, which penetrates through the column. Therefore the shape of the joint is hidden inside the column, not visibly apparent. For this reason, we operated X-ray inspection of the column and penetrating beam, on-site. Through this result we were able to estimate the shape of joint. Bending test of the joint was performed on models of the joints. The results of the bending tests of the connecting joints were compared with those without connecting joint inside the column. Consequently, it was possible to understand the difference between the strength of the each joint by the above results.
著者
岡本 肇 田中 享二
出版者
日本建築学会
雑誌
日本建築学会構造系論文集 (ISSN:13404202)
巻号頁・発行日
vol.76, no.667, pp.1569-1576, 2011-09-30 (Released:2012-01-13)
参考文献数
10

This paper reports the evaluation method of the waterproofing system for underground structure applied on earth retaining walls prior to concrete casting. The most important part for evaluating waterproofing properties of this system is a penetrated part through waterproofing, or a damaged part of waterproofing. For the penetrated part, the specimen of this system should be made of concrete casting vertically. For the damaged part, the specimen should be made of concrete using tall frame and casting vertically, or using small frame and rotating to accelerate bleeding. Then waterproofing property of this system is evaluated by pressurizing permeability test.
著者
小槻 祥江 磯田 和彦 清成 心 半澤 徹也
出版者
日本建築学会
雑誌
日本建築学会構造系論文集 (ISSN:13404202)
巻号頁・発行日
vol.86, no.786, pp.1156-1167, 2021-08-30 (Released:2021-08-30)
参考文献数
14

It has been reported that the vibration generated in a live hall located in an urban area during a live performance causes unpleasant vibration to surrounding buildings. This is because the vertical motion performed by a large number of audiences in accordance with a song and music. This vertical motion works as an excitation force to generate vibration and the vibration propagates to surrounding buildings through the ground. As a countermeasure against this vibration problem, we have developed a vibration-proof floor system using inertial mass devices. The feature of this vibration-proof floor system is that the forces of the spring supporting the floor and the inertial mass device arranged in parallel with the spring cancel each other out in opposite phases. Due to this feature, the force transmitted to the ground within a certain frequency range can be greatly reduced. In this paper, first, we show the response characteristics of the vibration-proof floor system in the frequency domain. From this response characteristics, it is confirmed that this vibration-proof floor system is effective countermeasure for the vibration problem caused by vertical motion of audiences in a live hall. Next, an excitation test of the principle model of the vibration-proof floor system is reported. Four disc spring units support weight of the model and an inertial mass device composed of a ball screw and a rotational weight is arranged in parallel. In this test, the model was excited with a sinusoidal wave using an excitation device. As a result of this excitation test, it is confirmed that the expected response characteristics for sinusoidal excitation can be realized. In addition, since the disc spring units and the inertial mass device have a slight hysteresis, it is necessary to evaluate this hysteresis damping in order to determine the performance of the vibration-proof floor system. The vibration-proof floor system is installed in an actual live hall with standing seats of 1,600. The specifications of the hall, the device configuration and the design performance of the vibration-proof floor system are shown. An excitation test was conducted in which the vibration-proof floor was excited by vertical motion of 1025 people. In this test, the verticals motions to the tempo of 2.0, 2.5 and 3.0 Hz and free verticals motions to the actual song were performed. From the measurement value obtained by the test, the vibration-proof floor behavior at the time of vertical motion was almost as designed. The reaction force response magnification of the vibration-proof floor system applied to the actual hall during the excitation test is obtained through a simulation analysis of the test. In this analysis, the device characteristics are evaluated using bilinear model that expresses friction of devices. The excitation wave used in this analysis is created as a combination of a sinusoidal wave of excitation frequency and twice and three times frequency of that. As a result of this analysis, it was confirmed that the reaction force reduction effect of proposed vibration-proof system is higher than that of the vibration-proof floor without inertial mass device. Through this paper, it is proved that the proposed vibration-proof floor system is very effective for the vibration problem caused by vertical motion of audiences during live performance.
著者
福田 隆介 福澤 栄治 小鹿 紀英 森川 博司
出版者
日本建築学会
雑誌
日本建築学会構造系論文集 (ISSN:13404202)
巻号頁・発行日
vol.68, no.570, pp.77-84, 2003-08-30 (Released:2017-02-08)
参考文献数
6
被引用文献数
2 1

At the September 11, 2001, terrorist attacks on WTC1 and 2, extensive structural damage, including localized collapse, occurred at the several floor levels directly impacted by the aircraft. Despite this massive localized damage, each structure remained standing for approximately one hour or one hour and a half. Although the damage of the beams and columns in outer framed tube of each tower are clarified at the published FEMA/ASCE report, the damage of the floor system and inner core columns are not estimated. The purpose of this study is to know the reason why the buildings remained standing at the impact through the several analytical studies, such as the impact analyses using the simplified model, that estimates the overall damage, and the rigorous finite element model, that estimates the local damage, and stress analyses after some structural members are lost.
著者
浅井 竜也 松川 和人 崔 琥 中埜 良昭
出版者
日本建築学会
雑誌
日本建築学会構造系論文集 (ISSN:13404202)
巻号頁・発行日
vol.87, no.795, pp.413-423, 2022-05-01 (Released:2022-05-01)
参考文献数
38
被引用文献数
1

In this paper, ship tracks during the huge tsunami in the 2011 Great East Japan Earthquake are extensively investigated based on Automatic Identification System data and others and ships smaller than 500 GT were identified more likely to be carried inland, resulting in potential impact load sources to buildings. Case studies are further made to compute required capacity of buildings against the combination of tsunami wave and impact loads due to tsunami-driven ships. It is then found buildings designed against tsunami wave and seismic loads will not sustain critical damages against ship impact when ship is smaller than 500 GT.
著者
肥田 剛典 永野 正行
出版者
日本建築学会
雑誌
日本建築学会構造系論文集 (ISSN:13404202)
巻号頁・発行日
vol.79, no.701, pp.923-932, 2014-07-30 (Released:2014-09-30)
参考文献数
25
被引用文献数
9 13

As the structural health monitoring tools, three subspace-based system identification methods, the ordinary MOESP, the N4SID and the PO-MOESP, were investigated to discuss the identification accuracy of natural frequency and damping factor of buildings. Fundamental case studies using SDOF response data revealed that the identification accuracy of the N4SID was lower than those of the ordinary MOESP and the PO-MOESP. This was because the 2-norm of the matrix applied to the noise in the N4SID was larger than the other methods. Finally, the difference in identification accuracy between three methods was verified by using the strong motion records of an RC super high-rise residential building during the 2011 off the Pacific coast of Tohoku Earthquake.
著者
戸塚 真里奈 早川 潤 青木 謙治 稲山 正弘
出版者
日本建築学会
雑誌
日本建築学会構造系論文集 (ISSN:13404202)
巻号頁・発行日
vol.87, no.798, pp.770-779, 2022-08-01 (Released:2022-08-01)
参考文献数
12
被引用文献数
2

In this paper, assuming that the embedding deformations under steel plates and dowels were almost equal to the deformations of damage zone in these joints, the evaluation methods of stiffness of tensile-bolted joints and dowel-types joints based on Strongest link model were proposed. To inspect the proposed methods, we compared and verified experimental and calculated results. The experimental and calculated values by the proposed methods were in good agreement and the effectiveness of the proposed methods was shown.
著者
丸山 一平 五十嵐 豪
出版者
日本建築学会
雑誌
日本建築学会構造系論文集 (ISSN:13404202)
巻号頁・発行日
vol.77, no.673, pp.323-332, 2012-03-30 (Released:2012-07-02)
参考文献数
55
被引用文献数
2 3

Prediction system for compressive concrete strength in aged structural member is proposed. This system is composed of models of rate of hydration, cement paste phase composition, heat production, specific heat, compressive strength, vapor desorption isotherm, coupled heat and moisture transfer. Each model is verified through experimental data. This system is aiming for the structural member which can not be accessed or can not be evaluated by the core sample test. Using non-destructive data or quality control sample's data, this system might illustrate the distribution and development of concrete strength in structural member properly. From the calculation results for a concrete member exposed to high temperature condition, strength development as well as distribution is quite sensitive to the boundary condition, and this concludes that the evaluation of structural member under such special condition needs precise boundary conditions.
著者
貞末 和史 北野 敦則
出版者
日本建築学会
雑誌
日本建築学会構造系論文集 (ISSN:13404202)
巻号頁・発行日
vol.84, no.761, pp.1001-1010, 2019 (Released:2019-07-30)
参考文献数
10
被引用文献数
1 1

As a new structural system with the structural characteristic same as steel reinforced concrete (SRC) and concrete filled steel tubular (CFT) structures, we are working on the development of steel concrete column-steel beam composite structures which filled concrete only in cross type steel. Over the past few years, we confirmed the mechanical behavior of column members and exposed type column bases in this new structural system, and by appropriate design it is possible to provide good seismic performance. Moreover, we proposed the simulation model of the restoring force characteristics of a column and an exposed type column base. Next, for practical application of this new structural system, it is necessary to examine the structural performance for beam-column connections, and propose the design method. In this paper, we confirmed the mechanical behavior of interior beam-column connections for steel concrete column-steel beam structures through the structural tests under the constant axial compression force and the cyclic horizontal load. The experimental parameters were selected reinforcement method of beam-column connection, the following reinforcement type were selected: (a) external diaphragms type, (b) inside stiffener type and (c) combination type which used external diaphragms together with inside stiffener. All test specimens were designed so that the failure of panel zone happened earlier than the failure of column and beam. Main discussion is concentrated on the failure state, ultimate strength and hysteresis characteristics. The test results indicated that the partial frame including beam-column connection had the stable hysteresis behavior until story drift angle of 3.0-4.0% radian, and the failure was concentrated in panel zone. Moreover, it was found that ultimate strength and ductility of the beam-column connection with large size external diaphragm were excellent, in comparison with the inside stiffener type beam-column connection. In the external diaphragms type, the tensile stress to transmit from the flange of beam to the orthogonal flange of panel zone increase. Moreover, the concrete of panel zone surrounded by external diaphragm, vertical stiffeners and steel flange can sustain large strain because of the confining action. This is the reason why the beam-column connection with external diaphragm showed advantageous structural characteristics. According to the AIJ design standard for SRC structures, the calculation value of ultimate strength of beam-column connection is calculated to the sum of the strength of the steel web plus the strength of the concrete in the panel zone. It was shown that the ultimate strength of beam-column connection could be evaluated on the safety side by a method based on the AIJ design standard. In addition, we confirmed that it was reasonably evaluate by added the strength of the orthogonal flange to the method based on the AIJ design standard. Three-dimensional nonlinear finite element analysis were conducted using ‘‘FINAL’’. The analytical values well predicts the experimental results until the attainment of the ultimate strength of the beam-column connection, and the maximum principal stress of steel was examined. It was confirmed that the tensile stress was transmitted to the orthogonal flange through the vertical stiffener.
著者
佐藤 智美 佐藤 俊明 川瀬 博 植竹 富一
出版者
日本建築学会
雑誌
日本建築学会構造系論文集 (ISSN:13404202)
巻号頁・発行日
vol.63, no.506, pp.83-92, 1998-04-30 (Released:2017-02-02)
参考文献数
32
被引用文献数
2 2

Using more than two hundred JMA-87 type strong-motion records we show that pseudo-velocity response spectra are noticeably different from Fourier acceleration spectra in several occasions because response spectra are sensitive to other frequency components or attenuation due to dispersion but insensitive to duration. Therefore, regression coefficients such as magnitude coefficients, attenuation coefficient, and site amplification factors for response spectra and Fourier spectra show clear differences. We conclude that physical characteristics of strong motion cannot always be represented by the regression coefficients for response spectra.
著者
松崎 伸一 久田 嘉章 福島 美光
出版者
日本建築学会
雑誌
日本建築学会構造系論文集 (ISSN:13404202)
巻号頁・発行日
vol.71, no.604, pp.201-208, 2006-06-30 (Released:2017-02-17)
参考文献数
48
被引用文献数
6 8

Using about 28,000 records from over 500 events up to August 2005, we determined an attenuation relation of JMA (Japan Meteorological Agency) seismic intensity, which is applicable to near source region. The determined attenuation relation was verified by comparing with data of recent earthquakes: the 2003 Off Tokachi, Off Miyagi and 2004 Chuetsu earthquakes of inter-plate, slab and crustal events respectively. Fairly agreement can be seen in these comparisons at close distance to the source. Iso-seismic intensity area by our relation is well corresponding to results of previous studies.
著者
松島 信一 川瀬 博
出版者
日本建築学会
雑誌
日本建築学会構造系論文集 (ISSN:13404202)
巻号頁・発行日
vol.65, no.534, pp.33-40, 2000-08-30 (Released:2017-02-03)
参考文献数
19
被引用文献数
9 12

We simulate strong motions in Kobe during the Hyogo-ken Nanbu (Kobe) earthquake of 1995 using a multiple asperity source model and a three-dimensional (3-D) basin structure. We derive a relatively simple rupture process, which consists of four asperities, using theoretical synthetics so that it matches the deconvolved bedrock motion at JMA Kobe. A realistic 3-D basin structure is constructed based on the exploration data. A 3-D finite difference method with fourth ordered staggered-grid scheme developed by Graves (1996) is used. The results show that with the combination of a relatively simple four asperity model and a 3-D basin structure, it is possible to reproduce strong ground motions in a wide area quite accurately. Peak velocity distribution is very similar to the JMA intensity distribution. From these results we confirm that we can reproduce strong ground motion in Kobe quite quantitatively by using a relatively simple source model that efficiently generate 1 second velocity pulses, together with a realistic 3-D basin structure.
著者
塩原 等
出版者
日本建築学会
雑誌
日本建築学会構造系論文集 (ISSN:13404202)
巻号頁・発行日
vol.73, no.631, pp.1641-1648, 2008-09-30 (Released:2009-09-30)
参考文献数
10
被引用文献数
12 8

This paper proposes a series of simple mathematical expressions which govern the ultimate behavior of two-dimensional reinforced concrete beam-column joints based on an observation of a failure crack pattern, and its compatible kinematic field, overlooked by the past researchers. The kinematic model is named nine DOF model in this report and combined with non-linear biaxial constitutive relation of concrete and steel to bear simple algebraic expressions for the ultimate moment capacity and moment at balanced failure, applicable to symmetric interior beam-column joints subjected four symmetric moments transmitted among the four ajacent members. The ultimate moment capacity is defined at which tensile yielding of longitudinal bars passing through the joint in the joint causes the expansion of diagonal cracks in the joint as well as local rotation of concrete panel and local crushing of concrete. The balanced failure of beam-column joint is defined at which tensile yielding of longitudinal bars passing through the joint and crushing of concrete start simultaneously. Simple equations for the upper bound value for the amount of reinforcement precluding the joint failure before yielding of longitudinal reinforcement are also brought.
著者
野田 賢 木村 俊明
出版者
日本建築学会
雑誌
日本建築学会構造系論文集 (ISSN:13404202)
巻号頁・発行日
vol.87, no.793, pp.285-294, 2022-03-01 (Released:2022-03-01)
参考文献数
22

This paper presents an optimization method of the joint arrangement for shell structures composed of CLT panels. The joining system is modeled as link elements with multidirectional stiffness. Their stiffnesses are calculated by multiplying the weight parameters defined as the design variables to the original stiffnesses. Furthermore, the joint arrangement is controlled by multiplying a power-law function to design variables. An optimization problem is formulated to minimize the strain energy. The effectiveness of the proposed method is shown through numerical examples. It is confirmed that the joint arrangement in each direction is optimized corresponding to the stress state.
著者
大塚 悠里 五十田 博 平石 久廣
出版者
日本建築学会
雑誌
日本建築学会構造系論文集 (ISSN:13404202)
巻号頁・発行日
vol.86, no.790, pp.1664-1673, 2021-12-01 (Released:2021-12-01)
参考文献数
14

The response analysis was conducted considering the site amplification effect on Japanese conventional wooden houses in metropolitan area in this paper. Then, the general tendency of seismic response of the Japanese conventional wooden houses was investigated from the analytical results. Finally, the wooden houses damage estimation map in the metropolitan area was shown for a disaster prevention material. The major findings obtained in this paper were as follows. 1) If the base shear coefficient was 0.1, the first story's maximum drift angle exceeded the drift angle of 1/20, judged as collapse at all analytical sites in the metropolitan area. If the base shear coefficient was 0.4, response drift angles showed values below the safety drift angle (1/30(rad.)) judged as severe damage in most sites.2) Even if the base shear coefficient was 0.6, the maximum response drift angle was larger than the safety limit drift angles (1/30(rad.)) at some sites in Site class 2 and Site class 3.3) In the Site class 3, it might be possibly less than acceptable drift angle even for houses whose base shear coefficient is not so high, if the site acceleration response spectrum is small within the shorter period less than about 1 second.4) It was not easy for wooden houses to reduce their response at the sites in Site class 2, and the sites judged as Site class 3 closer to Site class 2. 5) The phenomenal above mentioned in items 1)~4) were possibly understood from the acceleration response spectrum considering the site amplification effect.6) From the damage estimation map presented in this paper, it may be understood that the maximum response drift angle was large near Tokyo Bay and Chiba's coast and that the sites where the maximum response drift angle was relatively small were the northern Kanto region, such as western Saitama, southern Ibaraki, Tochigi, and Gunma.
著者
吉冨 信太 山川 誠 上谷 宏二
出版者
日本建築学会
雑誌
日本建築学会構造系論文集 (ISSN:13404202)
巻号頁・発行日
vol.69, no.586, pp.95-100, 2004
参考文献数
11
被引用文献数
2 11

A method is proposed for selecting optimum discrete sections of steel frames using a two-step relaxation method. At the first step, the discrete optimization problem is approximately solved by using a continuous optimization problem wherein approximate expressions are applied to the standard sections. At the second step, the near optimal set of discrete sections is selected using the solution of the relaxation problem whose design space is limited to the neighborhood of the optimal solution obtained in the first step. Through the numerical example of a 6-story 5-bay plane frame under elastic constraints, it is demonstrated that a discrete solution can be obtained whose rate of increase in total steel volume from the continuous optimum design is only 1.8%. This approach is general enoueh to be applied to the problems under elastic-plastic constraints and those with any type of standard section lists.
著者
柴山 淳 西山 峰広
出版者
日本建築学会
雑誌
日本建築学会構造系論文集 (ISSN:13404202)
巻号頁・発行日
vol.86, no.786, pp.1202-1212, 2021-08-30 (Released:2021-08-30)
参考文献数
24
被引用文献数
4

Geopolymer concrete has the potential to be an eco-friendly alternative to cement concrete because CO2 emissions in its production process can be reduced and industrial by-products such as fly-ash can be used effectively. The present study investigates flexural behavior of fly-ash based geopolymer concrete beams before yielding and its applicability as a flexural member. Eight beams consisting of four fly-ash based geopolymer concrete beams and four ordinary Portland cement concrete beams were cast and tested under four-point flexural loading. The experimental variables are combinations of reinforcing bar diameter and number of reinforcing bars, compressive strength and concrete types. In addition, non-linear three-dimensional finite element analyses were carried out. Bending moment-deflection behavior, crack width, crack space and number of cracks were examined. The experimental results were compared with the proposed equations provided by the AIJ design standard for reinforced concrete. The deflection and maximum crack width of the fly-ash based geopolymer concrete beams subjected to bending moment based on long/short-term allowable stress were similar to those of ordinary Portland cement concrete beams, and, therefore, they have an applicability as flexural members. The flexural behavior of fly-ash based geopolymer concrete beams prior to flexural yielding, except for the yielding deflection, could be predicted using the AIJ design standard. Making modifications to the coefficients related to the Young’s modulus ratio improved the accuracy of the prediction of yielding deflection. Although Young’s modulus of fly-ash based geopolymer concrete was lower than that of ordinary Portland cement concrete, the post-cracking stiffness of fly-ash based geopolymer concrete beams were not largely different from that of ordinary Portland cement concrete beams. The results suggested that the effect of tensile strength on the flexural behavior of the beams was greater than that of Young’s modulus of concrete. In addition, the crack width of the fly-ash based geopolymer concrete beams was similar to that of the ordinary Portland cement concrete beams, and could be predicted by the AIJ design standard for reinforced concrete.
著者
木村 祥裕
出版者
日本建築学会
雑誌
日本建築学会構造系論文集 (ISSN:13404202)
巻号頁・発行日
vol.76, no.664, pp.1143-1151, 2011-06-30 (Released:2011-11-16)
参考文献数
34
被引用文献数
10 15

In general, the seismic capacity of H-shaped beams with the local bucking is estimated by the two main structural factors. One of them is the plastic deformation capacity in the skeleton curve, and the other is the cumulative hesteresis energy in cumulative hesteresis loops. Their correlation has not been shown even though each one has been individually used as the seismic capacity of the beams. In this paper, the correlation between the cumulative hesteresis energy and the plastic deformation capacity of H-shaped beams are experimentally investigated in 11 test series and the empirical equations based on the previous experimental results are suggested.
著者
木下 拓也 大崎 純
出版者
日本建築学会
雑誌
日本建築学会構造系論文集 (ISSN:13404202)
巻号頁・発行日
vol.75, no.647, pp.113-119, 2010-01-30 (Released:2010-04-02)
参考文献数
17
被引用文献数
2 3

A new concept is presented for seismic isolation system using a compliant mechanism. Optimization approach is utilized for generating a truss structure that has specified equilibrium path, which can be achieved utilizing elastic deformation of a structure and geometrical nonlinearity. The truss structure can be used as a base-isolation system by assigning a path with gradually increasing load with respect to the displacement. Weighted sum of the error of the equilibrium path from the target path is minimized through optimization procedure. The compliant truss mechanism obtained from optimization is designed as the isolator model for the building frame. The effectiveness of our model of isolation system is validated by the result of time history analysis using recorded seismic motions.
著者
サエーンソイ ワラーンカナー 名和 豊春 トウーンカチョーンキット ピパット
出版者
日本建築学会
雑誌
日本建築学会構造系論文集 (ISSN:13404202)
巻号頁・発行日
vol.73, no.631, pp.1433-1441, 2008-09-30 (Released:2009-09-30)
参考文献数
16
被引用文献数
10 22

This study is aimed to elucidate the influence of ambient relative humidity on the compressive strength of fly ash cement paste. The ambient relative humidity has an influence on both the internal relative humidity and the hydration reaction, and further influences the compressive strength development. The experiment results revealed that the compressive strength of paste decreases with a reduction in ambient relative humidity. The same tendency can be found on the internal relative humidity and the hydration reaction as well. The detriment of strength development at low ambient relative humidity is affected by the retardation of the hydration reaction of C2S and C4AF. Moreover, the internal relative humidity at the time of test also has an influence on the compressive strength. The compressive strength decreased with the reduction in the relative humidity below the relative humidity lower than 95%. In addition, the compressive strength can be expressed as a function of the internal relative humidity and the hydrated gel volume derived from the degree of hydration of cement and the degree of pozzolanic reaction of fly ash.