著者
松下 哲郎 平尾 宙 丸山 一平 野口 貴文
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.623, pp.1-8, 2008-01-30 (Released:2008-10-31)
参考文献数
51
被引用文献数
8 2

In this study, Powder X-ray diffraction (XRD)/Rietveld analysis, which has been utilized in recent years as a technique for quantifying the crystal mineral phase of cement and cement paste, was applied to quantify the reaction rate of cement minerals and the proportions of hydration products. Its accuracy and availability was verified by comparing with the following properties, reaction rate of minerals by internal standard methods of XRD quantitative analysis, rate of heat liberation of cement by conduction calorimeter and amount of combined water of cement paste. Experimental factors were three types of cements, three levels of W/C, three levels of mixing/curing temperatures. The results showed that XRD/Rietveld analysis can quantify the hydration rates and products of cement paste with high accuracy.
著者
河合 真梨子 福和 伸夫 護 雅史 飛田 潤
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.74, no.636, pp.409-416, 2009-02-28 (Released:2009-11-02)
参考文献数
13
被引用文献数
3

This paper proposes a new place-name classification table considering geographical features and soil characteristics, which helps interpretation of seismic hazard maps. This table is classified into two soil groups (stiff soil and soft soil) based on the origin of their Chinese characters. We select bus-stop name from many kinds of place-name. This reason is the following two points. Distribution density of bus-stop is almost evenly in the city, bus-stop name mostly remain past place-name. The validity of the new place-name classification table and bus-stop name is clarified through case studies on the three major metropolitan areas of Japan.
著者
村上 雅英 田原 賢 藤田 宜紀 三澤 文子
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.61, no.481, pp.71-80, 1996
被引用文献数
10 4

About 2000 wooden structures were surveyed through 81. 6 ha, the seismic intensity was over 7, in Higashi Nada ward in Kobe-city where had been seriously damaged by the Hyogo-ken-Nanbu earthquake on Jan. 17th '95. The problems of the traditional Japanese post and beam wooden structures houses of two stories or less are not only pointed out, but also the cause of mechanism of collapses were determined according to the close investigation of 185 units through the seismic destruction area. It is recognised that quite numbers of the small and narrow houses with dry-wall exterior finish collapsed among many other Japanese traditional wooden structures with mud-wall exterior finish. The primary cause of collapses of these houses was that the structural planning was ignored on their floor planning.
著者
圓 幸史朗 河野 允宏
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.66, no.550, pp.47-55, 2001
参考文献数
35

Stochastic properties of broadband strong motions are investigated using the fractal source model. The model is described by the limited dynamic data reflecting uncertainty and heterogeneity on the fault plane. The soil ground model for source-site path is presented by the theoretical Green's function of the multi-layered half space. The simultaneous simulation test has been tried for the recorded ground motions at some sites in the 1994 Northridge earthquake and the 2000 Western Tottori prefecture earthquake. The average spectra and the duration time of the synthetics correspond well with those of the observed within 20 kilometers from the fault region.
著者
桑村 仁 松本 由香 武谷 政國
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.62, no.494, pp.129-136, 1997-04-30 (Released:2017-02-02)
参考文献数
21
被引用文献数
2 3

It has been pointed out in this decade that the currently used thick cold-formed box-section columns in building frames may fail in the mode of brittle fracture instead of local buckling, and that their ductility preceding brittle fracture may not be enough to resist a severe earthquake. In order to solve this problem, hot-rolled box-columns have been recently developed, in that the forming is done at high temperature to avoid cold working. In this study, the ultimate behaviors of the box-columns having through diaphragms, which is the current practice in building steel construction, were experimentally investigated. It was found that the newly developed hot-rolled box-columns exhibit much higher ductility than the conventional cold-rolled box-columns when the ultimate state is governed by brittle fracture as well as by local buckling.
著者
吉敷 祥一 山田 哲 竹内 徹 鈴木 一弁 岡田 健 和田 章
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.575, pp.113-120, 2004
被引用文献数
10 5

Many steel structures suffered damage at beam-to-column connections under the Northridge and Hyogo-ken Nanbu Earthquakes more than 8 years ago. After these earthquakes, a remarkable number of studies have been made on beam-to-column connections in U.S. and Japan. Nevertheless, in those studies, little attention has been paid to the point of repairing. The purpose of this study is to propose new ductile steel structure frame system, which realizes not only structural performances but also easy repairing after heavy earthquake. This system is based on bolted connections with split-tee. Main feature of this system is to limit plastic deformation to the splittee at bottom flange. To the contrary, the split-tee at top flange can be kept in elastic, because the center of rotation stays at the top flange of beam end.Consequently, when the structure using this system suffers compulsory deformation under the earthquake, the deformation concentrates on the split-tee at bottom flange. Finally, two series of static tests were conducted. First series are axial loading tests of the weak-web-split-tee elements, and second series are bending tests of beam-to-column connections having weak-web-split-tee. From the result of these tests, we verified that this system had efficient deformation capacity. In addition, the damaged part of this system would.be easy to repair or change to new one.
著者
林 康裕 宮腰 淳一 田村 和夫
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.62, no.502, pp.61-68, 1997
参考文献数
26
被引用文献数
14 3

We have revised the distribution of the peak ground velocities (PGV) in the Hanshin area during the 1995 Hyogo-ken Nanbu earthquake. The original PGV distribution was based on only the damage of residential houses, but the damage of the other types of buildings is also considered in the revision. In addition, we have refined the resolution of PGV in many cho whose area is broad. Evaluated PGV distribution has good correspondence with observed records and evaluated ground motions in the main shock except for the liquefied area like reclaimed land or the cho in which the PGV level drastically changes. On the other hand, the PGV in Nishinomiya city is not less than 60% of that in the Kobe city.
著者
米澤 健次 諏訪 好英 小野 佳之 長沼 一洋
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.601, pp.151-158, 2006
被引用文献数
1 1

Hydrogen explosion tests were conducted to grasp nonlinear response and to get its fundamental data for reinforced concrete walls subjected to hydrogen explosive load. In the tests, an explosive source (37m^3 -volume) that contained 30% hydrogen and 70% air was detonated, and the responses of the walls close to the source were measured. Two preliminary and three main tests were conducted for a variety of wall types with different thickness, heights, and steel reinforcements. The walls were instrumented with pressure sensors, displacement sensors, strain gauges, accelerometers and thermocouple. Wide varieties of experimental data were obtained in damage ranging from elasticity to complete failure. It was also confirmed that the wall nonlinear response depends on the blast wave duration and initial natural period. With increasing the initial natural period, the higher vibration modes were appeared on the response of the walls. Furthermore effects of strain rate were quantitatively investigated on the basis of the test results.
著者
今岡 克也 桜井 秀浩
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.64, no.519, pp.47-54, 1999
被引用文献数
1 1

The 1997 Aichiken-Tobu Earthquake (M5.8) occured in 39 km depth beneath Mikawa region. By questionnaire survey method seismic intensitiy distribution was investigated to about 250 elementary schools in Mikawa region. And microtremor measurement have been carried out at the same schools. The purpose of this study is to interpretate the seismic intensity distribution from microtremor characteristics and souce effects. Seismic intensity increment is defined to be difference of seismic intensity of equivalent hypocentral distance in which source effects are excluded. In conclusion the period of peak horizontal-to-vertical spectral ratio of short-period microtremors is found to be in good agreement with seismic intensity increase. And the average of horizontal-to-vertical amplitude ratio of microtremors is better agreement with seismic intensity increase.
著者
磯部 大吾郎 レ ティタイタン
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.1659-1664, 2011-09-30 (Released:2012-01-13)
参考文献数
8
被引用文献数
1

Fire-induced collapse behaviors of a high-rise building with an outrigger truss system were verified using the ASI-Gauss technique. The effects of fire patterns and structural parameters on the redundant strengths were surveyed by observing the collapse initiation time: the duration from the beginning of the fire until collapse initiation. From the numerical results, it is confirmed that collapse initiation times are significantly affected by the member joint strengths if the axial force ratio is small on the condition that the fire pattern is nearly symmetrical, and the load paths to and from the outrigger truss system are sufficiently protected.
著者
平石 久廣 吉益 幸寛 露木 裕史 喜々津 仁密
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.672, pp.259-264, 2012-02-29 (Released:2012-03-07)
参考文献数
6

This paper studies seismic performance of reinforced concrete buildings under the effect of high wind. Three types of structures of earthquake-resistant construction, damper construction and base isolation construction, two types of seismic force of moderate earthquake and severe earthquake, and three different levels of wind load are investigated.Following items were found through this study; in the case that buildings form plastic hinge mechanism, they deform into one-way and show poor energy consumption, so, their deformation remarkably increases, and this increase is controlled if the damper with the same strength as the wind load is installed in the building.
著者
大森 博司 崔 昌禹
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.67, no.552, pp.109-116, 2002-02-28 (Released:2017-02-04)
参考文献数
18
被引用文献数
2 4

Evolutionary Structural Optimization (ESO) method is one of the most powerful and promising technique for pursuing the optimal structural form among the other methods as the homogenization design technique and the bubble method. Although it is easy to carry out the calculation of ESO, there have been remained some weak points in its evolutionary process, by which inefficiency of calculation is caused or unreasonable solutions are concluded. A new method through the usage of the contour lines is proposed in order to remove such defects of the usual ESO as well as to enable the structures to not only be scraped off but also grow up toward the final optimal structures. Numerical examples on the structural form creation for plane structures subjected to multiple loadings as well as shell structures are demonstrated so as to show the potential ability of the present method toward effective structural design tools.
著者
エスコバール・S ホセ・アルベルト ロペス・バティス オスカル 菅原 まりも
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.508, pp.93-100, 1998
被引用文献数
9 3

A methodology to locate and assess structural damage in reinforced concrete structures from the known modes and natural frequencies of the structures is presented. The damage is defined as the stiffness loss of the structures. Using the perturbation method, the dynamical characteristic changes and the corresponding structural properties such as the stiffness changes are related so that the damaged floors of a structure are located. With the use of the Baruch and Bar Itzhack equations, the perturbed stiffness matrix is adjusted. Comparing the non-damaged stiffness matrix with the obtained perturbed stiffness matrix, the structural elements' damage is located and assessed. The sensitivity matrix that defines the lateral stiffness' sensitivity to the elemental stiffness changes is introduced.
著者
山田 義智 東舟道 裕亮 上原 義己 崎原 康平
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.756, pp.139-148, 2019
被引用文献数
2

&nbsp;In order to conduct flow analysis of cement paste, mortar and concrete, it is important to obtain rheological constants representing the flow characteristics of the material. In this study, we measured cement paste's rheological constants by using rotational viscometer. Here, it was measured in consideration of flow history on cement paste. Furthermore, in this study, we derived the flow constitutive equation of the cement paste and proposed a marker particle visco-plastic finite element method. Using this marker particle visco-plastic finite element method, simulation of flow test of cement paste was attempted.<br>&nbsp;The results obtained from the experimental study and analytical study of this research can be summarized as follows.<br>&nbsp;Using a rotational viscometer, the flow curve of cement paste was measured for various shear conditions. It was confirmed that the flow curves of all cement paste samples can be approximated by the Bingham model under all shear conditions. And the obtained flow curve was approximated by the Bingham model, and the rheological constants (yield value and plastic viscosity) of the paste sample was determined. Thixotropy was confirmed in the flow characteristics of the cement paste sample from the obtained flow curves and rheological constants.<br>&nbsp;The cement paste was regarded as a visco-plastic fluid and derived the flow constitutive equation of visco-plastic fluid using overstress theory. The obtained flow constitutive equation considers non-Bingham characteristic, flow history, and pressure dependency of yield value. It was confirmed that the flow curves of cement pastes differing depending on shear conditions can be expressed by the proposed flow constitutive equation.<br>&nbsp;Marker particle visco-plastic finite element method was used to analyze the flow test of cement pastes. The results obtained by the analysis agreed well with the experimental results. Therefore, the marker particle visco-plastic finite element method and the rheological constants are effective.
著者
薫田 匡史 栗田 光樹夫 大森 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.77, no.676, pp.899-904, 2012-06-30 (Released:2012-07-27)
参考文献数
9

Recently, the construction of the large astronomical telescope has been planned for better astronomical observation. In this project, it is necessary to design the structure of the telescope economically as well as easy to construct. Additionally homogeneous deformation of the supporting structure of the telescope is desirable to realize the stable supporting system of the main system of the telescope. However it is not so easy to design such structure, because the various tilt angle caused by the rotation of telescope for astronomical observation result in the large amount of the change in the external load. In this paper, the scheme of multi-objective optimal design for truss structures supporting large telescope are proposed and demonstrated in an actually constructed 3.8 m telescope. Using SPEA2 as multi-objective optimal method, where standard deviation of nodal displacements is adopted to evaluate homologous deformation, simultaneously satisfies the requirement of both weight minimization and homologous deformation.
著者
李 暁赫 杉山 央 小野 克也 藤本 郷史
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.703, pp.1215-1225, 2014-09-30 (Released:2014-09-30)
参考文献数
18

Curing condition of concrete in early ages has a significant influence on the durability of reinforced concrete structures. The influence of curing condition in early ages on the carbonation of concrete was studied in this paper. Following results were obtained; 1) The accelerated carbonation depth of concrete depends on the strength at the age of 28 days. 2) Evaporation rate is a useful indicator of earlyage curing with respect to concrete carbonation.
著者
倉本 洋 勅使川原 正臣 小鹿 紀英 五十田 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.66, no.546, pp.79-85, 2001
被引用文献数
25 10

This paper shows a method of converting a multi-story building into the equivalent single degree of freedom (SDOF) system, which can be applied to performance-based seismic evaluation methods such as the Capacity Spectrum Method. The feature of the converting method is to use information obtained from non-linear push-over analysis. The validity and applicable scope of the converting method were examined through the earthquake response analyses for several regular and irregular shaped buildings in which the responses of the equivalent SDOF system and the multi degree of freedom system were compared. The analytical results showed that the earthquake responses of not only regular shaped buildings but also irregular ones can be predicted by using SDOF system converted by the proposed method. For relatively high-rise buildings, however, the higher mode effect should appropriately be considered to the response of SDOF system.
著者
山本 剛 井上 正文
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.81, no.724, pp.959-969, 2016 (Released:2016-06-30)
参考文献数
18

An eruption of Mt. Ontake on September 27, 2014, which was small scale stream eruption with about 500,000 ton volcanic products, caused 47 deaths and 6 missing. Though volcanoes take on serious aspect in actively in Japan, the concern with the effect of falling of volcanic ash in huge eruption to buildings has been growing. A large volume of ash fall can destroy a building or lead to a catastrophe causing tragic loss of human life. It is important to understand of a characteristic of sliding of volcanic ash depositing on the roof to estimate an amount of accumulation of volcanic ash on the roof. The aim of the present work is to observe behavior of volcanic ash on pitched roof and to understand the basic characteristics of the sliding of volcanic ash on the roof using a model testing. The model testing was carried out using a roof model consisted of two components: one was a roof and another was a supporting structure that held up the roof. These two components were jointed each other with a pin-connected which allowed the roof rotate and replace the roof to another type of roofs; an opposite side of the joint was connected to a crane attached on a ceiling in a laboratory. Four types of roof were prepared to investigate an effect of surface roughness of roof materials and shape of a surface of the roofs on the sliding. The types of roof covers were cement tile, plane Galvalume steel plate, plane Galvalume steel plate with straight line roofing and Galvalume steel plate with seven steel plates substituted for snow steps. The sliding of volcanic ash on the roof could be occurred when the crane pulled a free end of the roof upward. The pitch of the roof was increased until the falling of volcanic ash depositing on the roof was observed and a drop amount of the volcanic ash from a roof and a pitch of a roof were measured when the sliding of the volcanic ash stopped. Two kinds of volcanic ash which were spouted from Mt. Sakurajima in 2014 and from Mt. Shinmoedake in 2011 were accumulated on the roofs. Each roof had a unique characteristic of sliding of volcanic ash when a drop amount of the volcanic ash from the roof reached to same value. This result suggested that the sliding of volcanic ash on the roof depended on surface roughness of roof material and shape of a surface of the roof. A trapezoid model which approximated to a cross-section shape of volcanic ash on the roof was developed to calculate an angle of a slope φ of the volcanic ash which was a value of the angle of slope when the sliding was over. The angle of a slope φ was closed to an angle of internal friction when the pitch of roof was small; it gradually decreased close to 70% of an initial value. A pitch of the roof θMAX which was maximal angle that the volcanic ash could accumulate was calculated by extrapolation of the angle of a slope φ. The values were in the range of 21° to 26°. This result suggested that sliding would occur and could cause serious damage to buildings in huge eruption. These results indicated that the sliding of the volcanic ash would be one of issues in volcanic disaster prevention in Japan and the angle of a slope φ could be main factor to understand the sliding. Further research on angle of a slope φ was needed to clarify the characteristics of the sliding.
著者
小山 智幸 松藤 泰典 小山田 英弘 山口 謙太郎
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.600, pp.17-21, 2006
参考文献数
17
被引用文献数
3 2

In this paper, the tendency of labor accident affected by hot weather ambience were analyzed and discussed. At first, severity of construction works was evaluated in relative metabolic rate (RMR), and temperature limit of works was shown as some index, such as the wet bulb glove temperature (WBGT). The frequency of heat attack occurrence correlated with the number of the days when the maximum temperature became higher than 30℃. Because many processes were executed over the temperature limit, labor accident tended to occur in hot season, and particularly the fall accident from 10 a.m. to 3 p.m. due to high temperature.
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
被引用文献数
15 7

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.