著者

花島 晃 平野 富之

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.496, pp.53-58, 1997-06-30 (Released:2017-02-02)

参考文献数

3

---

In constructing a 256-m-high skyscraper on a reclaimed land, there are two problems awaiting solution; one is negative friction of piles due to consolidation settlement of alluvial clay layer under the reclaimed soil layer and settlement of diluvial clay layer locating deeper than the bearing stratum of the building. These were handled in conducting subsurface exploration, foundation design, study on construction methods and construction work at the site controlled by measurements. Land settlement due to construction of a building should be estimated not only by evaluating increase in load and volume compressibility but also by considering 1) changes with time in ground-water table during excavation work and 2) load re-distribution effect due to rigidity of superstructure as a whole

著者

金子 治 中井 正一

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.79, no.695, pp.83-91, 2014-01-30 (Released:2014-07-10)

参考文献数

23

被引用文献数

3 4

---

There were several cases reported where buildings had to stop functioning normally because of the damage to foundations during the 2011 Great East Japan earthquake. The authors carried out static analyses using a foundation structure model in order to investigate the cause of damage to pile foundations by focusing on three typical buildings. Lateral load at pile head and differential movement of soils were estimated based on a seismic response analysis by using recorded ground motions of the 2011 Great East Japan earthquake and by looking into the soil profiles and structural characteristics of buildings. Load-deformation characteristics of pile elements and soil springs were formulated so that the model can incorporate nonlinear behaviors. Results obtained from the analysis explain fairly well the actual damage of pile foundations. It was confirmed that a controlling factor causing damage to pile foundations is the existence of soft soils and the variation of surface soil layers. The proposed procedure can be considered as a practical seismic design method of foundations that ensures a required performance for large earthquakes.

著者

在永 末徳 乗政 全成 寺尾 直樹 行平 信義 尾池 哲郎

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.70, no.589, pp.23-28, 2005-03-30 (Released:2017-02-11)

参考文献数

8

被引用文献数

2 2

---

The casting calcium carbonate, which is made by pressed lime, acquires the compressive strength on two stages. The behaviors of compressive strength of the casting calcium carbonate on these stages are investigated by examining the compressive strength and the rate of water absorption. At the first stage the casting calcium carbonate, in the form of the lime, gets the compressive strength by the cast pressure. We find the compressive strength can be expressed by the equation associated with the rate of water absorption. At the second stage it acquires the compressive strength as the carbonation proceeds. We find the relation between the rate of water absorption and the rate of carbonation is linear. We then conclude the compressive strength of the casting calcium carbonate can be expressed by the rate of carbonation.

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

松塚 展門 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.88, no.814, pp.1655-1664, 2023-12-01 (Released:2023-12-01)

参考文献数

10

---

The Kintaikyo in Iwakuni-City, which spans the Nishiki-River in Yamaguchi Prefecture, was built in 1673. The design of the arch of this bridge was studied. It was assumed that the arch of this bridge were designed in arch coordinates with multiple catenary. As a result, the design theory of this bridge was derived for the first time. The multiple catenary was identified from the Kintaikyo in Heisei, and The new Kintaikyo drawing for KAKEKAE was created that is harmony and orderly. Based on this drawing, it was proved that a harmony and orderly bridge can be realized by 3D-CG.

著者

磯部 大吾郎 江口 正史 今西 健介 佐々木 嗣音

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.72, no.612, pp.73-78, 2007-02-28 (Released:2017-02-25)

参考文献数

15

被引用文献数

3 2

---

A controlled explosion technique using high explosives has been developed in recent years. Although the blast demolition technique increases work efficiency, it poses a high risk of damaging neighboring buildings, especially in urban areas. It also requires high levels of knowledge and experience, which are very difficult for general engineers to master. To familiarize the demolition technique among engineers, numerical assumptions using computational analysis in devising the blast demolition have become essential in ensuring the success of this technique. One of the objectives of this study is to perform some blast demolition analyses of framed structures using a dynamic finite element code, whose validity against impact collapse problems of large-scale structures has recently been developed and verified. Another objective of this study is to develop a mimic demolition experimental system that uses magnetic devices to express member fracture caused by explosion. The magnetic field of the devices is controlled by a blast interval controller and power switches, which control the binding of each connection in the framed structure. The experimental system does not use explosives or any such dangerous substances, and multicycle use is possible. An experiment is carried out to compare quantitatively with the numerical result.

著者

田中 英之 田村 幸雄 大竹 和夫 中井 政義 金 容 徹

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.678, pp.1211-1218, 2012-08-30 (Released:2012-10-15)

参考文献数

17

被引用文献数

1 3

---

Tall buildings have been traditionally designed to be symmetric rectangular, triangular or circular in plan, but recent tall building design has been released from the spell of compulsory symmetric shape design, and free-style design is increasing. One important advantage for this trend is that rather complicated sectional/structural shapes are good with regard to aerodynamic properties for across-wind responses, which is a key issue in tall building wind-resistant design. A series of wind tunnel tests have been carried out to determine wind forces and wind pressures acting on the large number of tall buildings with various configurations. The results of these tests have led to comprehensive understanding of the aerodynamic characteristics of various tall building configurations.

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

井澤 保一 小林 正人

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.88, no.807, pp.746-757, 2023-05-01 (Released:2023-05-01)

参考文献数

20

被引用文献数

1

---

The occurrence of earthquake ground motions exceeding the assumed design level may lead to plasticization of the superstructure of seismically isolated buildings. It is known that the plasticization of the superstructure is accompanied by a rapid development of deformation (quasi-brittle). In this paper, the relationship between the Ds value and the ductility factor is determined using incremental dynamic analysis, and the nature of quasi-brittle is quantified by formulating this relationship. Furthermore, seismic safety evaluation method for the limit state of seismic isolation layer and superstructure in seismically isolated buildings is proposed using this relationship.

著者

谷地畝 和夫 鈴木 彰 齋藤 雄太 得能 将紀 小林 正人

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.781, pp.381-391, 2021 (Released:2021-03-30)

参考文献数

17

---

In recent years, there is concern about the occurrence of extreme ground motions that greatly exceed the amplitude levels and durations expected in conventional design level. Therefore, seismically isolated buildings are required to secure the seismic isolation performance for small earthquakes and to suppress the excessive displacement of the seismic isolation layer for extreme ground motions. As one of the effective means to meet the above requirements, in addition to an electromagnetic switching semi-active seismic isolation system, a cheaper and more reliable passive damper is being developed. Meanwhile, the authors have proposed a dead zone mechanism that is an accessory device connected to the existing oil damper. When the relative displacement of seismic isolation layer is smaller than the set amplitude (medium and small earthquakes level), the dead zone mechanism only slides and no damping force is generated in the oil damper, and when the amplitude is larger than the set amplitude (extreme ground motions), this mechanism generates damping force and suppresses excessive displacement. Furthermore, one of the features of this mechanism is that it has a mechanism that automatically returns the rod to the original position after the earthquake. In this paper, we analyze the seismic response of seismically isolated buildings using the dead zone mechanism to understand the response characteristics.  1) When the publicly announced wave and pulse ground motions are used as input earthquakes, an oil damper with a dead zone mechanism is used in the seismic isolation building to ensure seismic isolation performance for small and medium earthquakes, while suppressing excessive displacement of the seismic isolation layer for extreme ground motions. It was confirmed that the desires effect of doing was obtained. In this analysis case, the most effective performance was shown when the dead zone width was set to 15cm. 2) When the long period ground motions is used as the input ground motions, the acceleration response of the GAP model is larger than that of the OD model, but the acceleration is small at about 100~200cm/s2, which is considered to be within the allowable range for seismic isolation. 3) It was confirmed that the automatic return spring in the dead zone mechanism automatically returns the rod in the mechanism to the neutral position at the end of the earthquake. Therefore, by automatically returning the dead zone mechanism to the automatic return spring in the dead zone mechanism, it is possible to maintain the structural performance assumed at the time of design even when multiple earthquakes occur in a short period of time. 4) In all earthquakes, when the seismic isolation layer displacement reaches the dead zone width, the absolute acceleration increase in the lower layer. The cause is considered to be a reaction force due to the elements of the dead zone mechanism contacting each other. The 1/3 octave band analysis was applied to the time history waveform of the absolute response acceleration above the seismic isolation layer of each model. It was confirmed that the value was sufficiently smaller than the judgment value of the rank with the lowest anxiety level, compared with the evaluation curve in the anxiety level evaluation by Takahashi et al. Therefore, it was confirmed that the increase in acceleration response when the elements in the dead zone mechanism were in contact had little effect on the habitability.

著者

伊藤 洋介 河辺 伸二 大羽 慧

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.82, no.739, pp.1321-1327, 2017 (Released:2017-09-30)

参考文献数

12

被引用文献数

1 2

---

It is expected that elderly people can't remove snow on their own, and have a trouble going out. There are some ways to remove snow which do not require physical effort, but each conventional way has problems. Therefore, the authors have attempted to invent the “heating mortar block system” to remove snow. In this system, electromagnetic waves are generated by the oscillator, and then irradiated mortar blocks with. A heating mortar block is composed of 3 layers; 1. electromagnetic absorption material 2. base material (without electromagnetic absorption ability) 3. electromagnetic shielding material. Electromagnetic absorption material placed near the surface absorbs electromagnetic waves and converts it into heat. This system uses this heat to melt snow on the blocks. Electromagnetic absorption material is mortar mixed with electric arc furnace oxidizing slag as aggregate (hereinafter, called “the slag mortar”), and base material is a mortar mixed with sand as aggregate (hereinafter, called “the sand mortar”). According to preceding research, there is a correlation between abilities of electromagnetic absorption and heating. But, the characteristics of electromagnetic absorption and heating about electromagnetic absorption material composed of the slag mortar and the sand mortar has not been studied enough. So, the purpose of this study is to clarify these things and develop the base theory to design heating mortar blocks absorbing the electromagnetic waves and heating well. Ability of electromagnetic absorption is evaluated with return loss calculated by S-parameter method. Within the measuring range, following things were clarified. (1) When the sand mortar is superposed under the slag mortar, the thickness of which the sand mortar causes the prominent absorption of electromagnetic waves at specific frequency (hereinafter, called “peak”), has a period. And, it is possible to choose a thickness from some thickness by considering this period. (2) When the sand mortar is superposed under the slag mortar, it is possible to determine the thickness, by specifying the thinnest thickness through the experiment and using the equation produced in this study. (3) It is possible to adjust the temperature rises of the heating mortar block without changing the thickness of the slag mortar which is the electromagnetic absorption material, by just changing the thickness of the sand mortar. (4) When the thickness of sand mortar superposed under the slag mortar is 30mm, 62mm or 93mm and it is irradiated with electromagnetic waves of frequency 2.45GHz, the temperature rises 20.6 °C, 17.3 °C or 19.2 °C each. In these thickness, return loss also rise as a peak. (5) When the sand mortar is superposed under the slag mortar, it is possible to evaluate the heating ability by return loss.

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 4

---

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 10

---

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 5

---

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

池田 雄一 矢吹 信喜

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.88, no.805, pp.347-355, 2023-03-01 (Released:2023-03-01)

参考文献数

28

---

During the building construction, contractors are required to measure the completed form and calculate the quantity and are increasingly employing point cloud data for this purpose. Using point cloud data is expected to perform higher productivity than the conventional manual measurement and taking pictures. This paper proposes a new pile center measurement method using point cloud data obtained by Structure from Motion (SfM) and Building Information Modeling (BIM). The efficiency, cost, and accuracy of the proposed a pproach were investigated compared to the conventional surveying method.

著者

松沢 晃一 橘高 義典

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.707, pp.1-7, 2015-01-30 (Released:2015-03-30)

参考文献数

31

被引用文献数

1

---

This paper reports on the influence of coarse aggregate on the fracture properties of concrete subjected to high temperatures up to 800℃. The fracture properties were evaluated based on tension-softening curves which were determined by polylinear approximation through inverse analysis of load versus crack mouth opening displacement (CMOD) curves, obtained from wedge-splitting tests using a dedicated analysis program. The follow conclusions were found in this study: The initial cohesive stress of mortar was higher than that of concrete. And the fracture energy of concrete was higher than that of mortar.

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.