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Article type: Cover
1978 Volume 266 Pages
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Published: April 30, 1978
Released on J-STAGE: August 22, 2017
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Article type: Cover
1978 Volume 266 Pages
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Published: April 30, 1978
Released on J-STAGE: August 22, 2017
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Article type: Appendix
1978 Volume 266 Pages
App1-
Published: April 30, 1978
Released on J-STAGE: August 22, 2017
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Article type: Index
1978 Volume 266 Pages
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Published: April 30, 1978
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Article type: Appendix
1978 Volume 266 Pages
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Published: April 30, 1978
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MOOHAN KIM, TAKASI YOKOYAMA, MASAYUKI TABATA, YOSHIRO KOH, EIJI KAMADA
Article type: Article
1978 Volume 266 Pages
1-9
Published: April 30, 1978
Released on J-STAGE: August 22, 2017
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It is the aim of this study to undertake to provide comprehensive laboratory data on air entrainment which influence to early frost resistance of artificial lightweight aggregate concrete, and present the qualitative and quantitative entraining air which is valid and necessary to prevent the early frost damage of artificial lightweight aggregate concrete by comparing and investigating air content with the other factors influencing to frost damage of concrete at early ages. On the basis of these test conditions, the following observation and conclusions seem warrant and appropriate ; 1. The use of intentionally entrained air by air entraining agents and air entraining water reducing agents results in as an excellent effect in early frost resistance of artificial lightweight aggregate concrete as normal weight aggregate concrete. In case of artificial lightweight aggregate concrete, the adequate amount of intentionally entrained air was found to be 5 percent or more of nominal air content in placing concrete, which is enough capable to get the inferential strength ratio of 80 percent or more after 5 cycles of freezing and thawing, and it is very clear that there is a correlation between air content and early frost resistance of artificial lightweight aggregate concrete. 2. The water cement ratio gives comparatively a corresponding influence in early frost resistance of artificial lightweight aggregate concrete. 3. The influence of water content and kind and moisture content of aggregate are not to be compared with intentionally entrained air in the effect in early frost resistance of artificial lightweight aggregate concrete.
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SATORU KAZAME
Article type: Article
1978 Volume 266 Pages
11-18
Published: April 30, 1978
Released on J-STAGE: August 22, 2017
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The study reported was made experimentally on the damping of building, considering mainly the effect of the pile foundation and the surface layer upon the building vibration. In the experment, were used the models of single-story building and piles both made of steel, and a rubber sheet for the surface layer. The models were subjected to the free, force and randam vibrations in the following cases, 1) Building fixed at foundation (B), 2) Suface Layer only (S.L.), 3) Combined system (F+S.L.) of, that is of pile fouudation (F) and surface layer, and 4) Combined system (B+F+S.L.), that is of building and pile foundation with surface layer, and cases of 2), 3) and 4), in which the surrounding of surface layer was treated in both ways such as restrained and free. From the results of experiment, the following facts have been proved. In the case of the surface layer of which surounding is restrained, the damping of combined system (B+F+S.L.) is much influeced by the swaying, and it approaches that of (F+S.L.) as the swaying becomes larger. A similer tendency can be seen in the period of vibration. In the case of the surface layer with a free boundary, the mode of vibration of combined system (B+F+S.L.) is much dominated by the vibration mode of surface layer (S.L.) or by that pile-foundation building (B+F), and the damping of (B+F+S.L.) approaches that of S.L. or of (B+F), as similarly to the tendency which we have seen in the mode of vibration of models.
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BEN KATO, RYOICHI SHOHARA
Article type: Article
1978 Volume 266 Pages
19-29
Published: April 30, 1978
Released on J-STAGE: August 22, 2017
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Hithertofore, the flexural and shear strengths of Steel-Reinforced Members have been evaluated indipendently, although the change of the bending moment along the length of a member should balance to the shearing stress in the cross section. This paper submits a model which has the consistency between the bending moment and shearing stress and evaluates the flexural and shear strengths of Steel-Reinforced Concrete Members on a unified basis. In this analysis, the equilibrium conditions of forces are assured, though the compativilities of the strains and deformations are disregarded and the stresses of composing materials do not exceed their ultimate value throughout the entire member body. Therefore the predicted strength shows the lower bound strength of the member. The stress-strain relationship of the steel is assumed to be elastic perfectly plastic and the concrete is assumed to have enough ductility against compression keeping its ultimate strength. According to this analysis the occurence of shear bond cracks is not always followed by the failure of the member. A series of tests consist of 50 specimens was carried out. The correlation between these test results and this theoretical prediction was satisfactory.
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MASAKAZU OZAKI, YOSHIKAZU KITAGAWA, SADAIKU HATTORI
Article type: Article
1978 Volume 266 Pages
31-40
Published: April 30, 1978
Released on J-STAGE: August 22, 2017
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It is one of the most important problems in earthquake engineering to predict the intensity of future earthquakes statistically from the past available earthquake recording data, as precise earthquake forecast is difficult in the present stage. In the process of the prediction, the selection of the past earthquake recording data and statistical method of analysis are the most important, because the available earthquake recording data are not sufficient. Many researches and investigation have been carried out in this field in Japan. However, there is no research on the prediction of the intensity of future earthquakes based on the theory of extremes developed by E. J. Gumbel. This paper deals with the expected values of the intensity of future earthquakes on base rock mainly. This paper is summarized as follows; (1) Taking into account of the results of reexamination for the data and method of analysis which have been used by many researchers in this field (see Table 1), the following data and method are used; (i) the carthquake data in the vicinity of Japan for the period of 1644〜1972 (329 years), (ii) Dr. Kanai formulate wich give a maximum intensity at the base rock and on the surface of the ground, (iii) Gumbel's Second Asymptotic Distribution in statistics of extremes. Especially about the data before 1926, the treatments with characteristics of velocity at the base rock are applied as follows; (i) the major earthquakes having 2.5cm/sec or more at the base rock are estimated from the destructive earthquakes in the Science Calender, (ii) considering the annual magnitude and energy distribution curves in Figs. 1, 2, 3 and 4, it is aasumed for the small or middle earthquakes less than 2.5cm/sec. at the base rock that the frequency of earthquake occurrence is same as that after 1926 year. (2) The expected maximum velocity at the base rock with standard deviation vs. return period are predicted at the center of Tokyo (35.7°N, 139.8°E) in Fig.6. The expected maximum acceleration, velocity and displacement on the surface of the ground are also listed in Table 4. In addition, the calculated maximum velocity values at the base rock for each year are listed in Tables 2 and 3. (3) Regional distributions of the expected maximum velocity at the base rock are estimated for the return period 50, 100 and 200 years in the vicinity of Japan. As seen in Figs. 7, 8 and 9, the areas where the earthquake danger is considered to be high are generally as follows; (i) the coast area on the Pasific Ocean side from the Hokkaido to Tohoku and Kwanto districts, (ii) the area from west part of the Chubu district to all parts of the Kinki district, (iii) the area from the west part of the Shikoku to the east part of the Kyushu district. (4) For the practical seismic design purpose, the regional seismic zoning map is proposed as reflecting the past seismicity. As seen in Fig.10, Japan is divided into three divisiins by the criterion of seismic activity relatively as follows; A) high seismisity region, B) middle seismisity region and C) low seismisity region.
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YOSHIZO DOBASHI, TAKESHI UCHIYAMA, MASAIKI UEDA
Article type: Article
1978 Volume 266 Pages
41-49
Published: April 30, 1978
Released on J-STAGE: August 22, 2017
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The prediction of a sequence of gradual actions of a plate as it is subjected to incremental loading is among the most interesting structural problems. The report describes elasto-plastic large deflection analysis of so-called laminated plates comprising anisotropic laminae or thin layers each of which may have any prescribed set of mechanical properties. The method proposed enables the pursuit of extension of plastic regions within a plate in the transverse direction as well as the demonstration of its behaviors during elastic-to-plastic transitional deformation. Circular and rectangular cases are equally analyzed as examples and the results prove in fairly good agreement with the corresponding ones of past experiments.
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SUKENOBU TANI, YASUO KATAOKA
Article type: Article
1978 Volume 266 Pages
51-61
Published: April 30, 1978
Released on J-STAGE: August 22, 2017
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In recent years, folded plate analysis are mostly based on finite element method, finite segment method and finite strip method, and they are useful for solving the problems of folded plate structure. The object of the present investigation is to develop least square-point matching technique to analyse continuous folded triangular plates, Fig.1, based on elasticity theory. In this method, compatibility and equilibrium conditions are strictly satisfied in the considered region, and boundary conditions for continuous ridge and side of plate are satisfied at selected points. For the solution of a structure subjected to uniform load, the procedure is to derive first all equations of stress and displacement components in the bending of plates and two dimensional problems, and then to expand these equations in trigonometrical series. The derivation of these equations is described in section 2. The terms higher than N will be omitted, and the problem is then to find eight kinds of coefficients by least square point matching technique. This is done by satisfying the boundary conditions at selected points of ridge that are obtained by function of point matching. These procedures are described in sections 4. In section 4, considerations of convergence and error of boundary condition are discussed for solving the problems of folded triangular plate. The boundary conditions for continuous ridge and examples using this method are presented in section 5.
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HISHASHI SHIMODAIRA
Article type: Article
1978 Volume 266 Pages
63-71
Published: April 30, 1978
Released on J-STAGE: August 22, 2017
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In this paper, some considerations on eight node isoparametric shell elements are described. A formulation of the element stiffness matrix and a calculation procedure which reduce computation are presented. The effects reducing the order of integration of the element stiffness matrix are verified by some numerical examples. The limit of the application of the element to thin shell analysis is investigated by numerical examples and some criteria for the usage of the element are discussed. A calculation method of nodal stresses which is consistent with reducing the order of integration of the element stiffness matrix is presented. The presented method, the method which uses the conventional strain matrix and Hinton's method are investigated by some numerical examples.
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GENGO MATSUI, HITOSHI SEYA
Article type: Article
1978 Volume 266 Pages
73-85
Published: April 30, 1978
Released on J-STAGE: August 22, 2017
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YUKIO TAMURA
Article type: Article
1978 Volume 266 Pages
87-95
Published: April 30, 1978
Released on J-STAGE: August 22, 2017
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To simulate the vortex-induced vibration of a circular cylinder, a wake oscillator the length of which flactuated was proposed in this paper. In addition, the effects of the discharged vortices from the wake oscillator were represented by a negative viscous damping of equivalence. The motion of the wake oscillator was expressed by a nonlinear differential equation called "Van der Pol's equation". The equation of motion of the wake oscillator when the cylinder was excited externally, was analized approximately, and examined into the synchronization of frequencies of the lift coefficient and the cylinder motion. The theoretical region of synchronization was compared with some experimental results, and it became clear that the theoretical value agreed fairly with the experimental values. To know the wake behavior on the circular cylinder excited externally over the wide range of wind speed, the nonlinear equation was analized numerically by a digital computer. The numerical results, which were the relation between wind speed and the amplitudes of lift coefficients, the frequencies of cylinder motion and lift coefficients, and the phase shifts of them, proved that the proposed nonlinear wake oscillator would be able to become good model which represented the wake of cylinder vibrated by vortices.
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MASAMICHI ENAI, NOBORU ARATANI
Article type: Article
1978 Volume 266 Pages
97-103
Published: April 30, 1978
Released on J-STAGE: August 22, 2017
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In this report, the authors discussed the temperature difference between mean room air temperature θ^^-_<im> and mean outdoor temperature θ^^-_0 in a day, the controlled room air temperature θ^^-_<is> and the amount of the week's consumed fuel W in the partially and intermittently heated houses. Annual consumption of fuel can be obtained by the degree-days method with the following results. 1) ⊿W/⊿(θ^^-_<im>-θ^^-_0)=const. 2) When the ratio k can be obtained, θ^^-_<is> can be calculated by the next equation. θ^^-_<is>=θ^^・_<is>+a・θ^^-_0, θ^^・_<is>=θ^^-_<is> (θ^^-_0=0). 3) If the temperature difference⊿θ_n from the free heat can be assumed by the measured results, the required fuel w in a day shall be inferred by the next equations. p=(θ^^-_<im>-θ^^-_0-⊿θ_n)/(θ^^-_<is>-θ^^-_0-⊿θ_n), w=p(θ^^-_<is>-θ^^-_0-⊿θ_n)⊿W/⊿(θ^^-_<im>-θ^^-_0). The annual consumption of fuel in the partially and intermittently heated houses is sometimes bigger than that of the entirly and continuously heated houses, mostly because of the insufficient insulation. The thermal living condition in such houses is not very good. But if extra heat is slightly supplied at night, the strong radiation from a stove will be reduced and the thermal living condition in the daytime will be better than that in the case of the intermittent heating. In any case, the thermal living condition or the amount of consumed fuel is not only affected by the thickness of thermal insulation but also by the type of heating system and the heating custom. And the thicker the thermal insulation gets, the better the thermal living condition will be. The common interest in the room temperature will change from the mere warmth around a stove to the thermal living condition of the whole house in the future.
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TATSUO OKA
Article type: Article
1978 Volume 266 Pages
105-114
Published: April 30, 1978
Released on J-STAGE: August 22, 2017
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This part is intended to investigate the structure of thermal diffusion in a wind tunnel and to compare measured temperature distribution with numerical solutions by the method which has been described previously. For this experiment, roughness elements (zh=2.8cm) were used in a wind tunnel. A part of it is heat produce area (60×60cm) which can be controlled from 0 to 2kw. Summary of results obtained may be as follows. 1. The structure of air flow when the model is not heated up. Wind profiles can be given by log-law up to 10cm in height above the model. Prandtl's mixing length is expressed as l_z=0.11Z, as Reynolds stress is approximately constant in the boundary layer. Vertical eddy diffusivities are proportional to height and horizontal eddy diffusivities decrease with increase of height. 2. Thermal diffusion experiment. Air flow over the model was observed using emitted smoke, which shows that upward wind velocity due to temperature gradient tends to increase with increase of quantity of heat from the model and decrease of wind velocity in the wind tunnel. The same result is obtained from measured temperature distributions in sectional figure. 3. Comparisons between measured and calculated temperature. The KEYPS formula which is expressed by mixing length and Richardson number (Eq.4-9) was used to estimate the eddy diffusivities in unstable conditions, in which the constantγ_z=100 was used in calculation. Calculated results were in good agreement with measured results in comparison of isotherms, where the correlation coefficients between measured and calculated temperature were from 0.95 to 0.97.
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YOSHITSUGU AOKI
Article type: Article
1978 Volume 266 Pages
115-121
Published: April 30, 1978
Released on J-STAGE: August 22, 2017
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The aim of this study is to develop a method of optimization of importance factor. We assume that building system is determined by three aspects, that is, physical, economical and social aspect. From a physical aspect, building system is denoted by physical variables; load effect S, strength R and magnifying factor of strengthθwhich is called importance factor. From an economical aspect, construction cost is a variable indicating a building system. From a social aspect, the social utilities of building system are represented fundamentally by an expected value of total utility during design life span of building under the failure probabilities determined by importance factor. Under the above formulation, we determine the value ofθcorresponding to the maximum total social utility. This problem is denoted by equation (9)〜(18). This system of equations follows equation (19). This equation means a principle at maximization of utility from a safety point of view.
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TETSUO SEGUCHI
Article type: Article
1978 Volume 266 Pages
123-132
Published: April 30, 1978
Released on J-STAGE: August 22, 2017
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The relation between languages using in design process and design process is important. Design processes are composed of the process of concept and the process of form. Each process has languages suitable for that process. The design word is languages of the process of concept. The design word is a mirror of the concept. So the design word is equal to the concept. There are three stages of the concept on design processes. Namely they are the stage of finding and researching a new concept, the stage of fixing that consept, and the stage of applying and reproducing that concept. Those stages explain the use patterns on design processes. And they will compose a process model of design. Design process model and design tool should be reconsider from a new viewpoint. Its viewpoint is a degree of relations between designers and them. There are some subjects after this. We should study not only design words but pictures and drawings etc.
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SHINGO TAMAKI, HIROSHI SUZUKI, NAOFUMI ODA
Article type: Article
1978 Volume 266 Pages
133-142
Published: April 30, 1978
Released on J-STAGE: August 22, 2017
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This report has two purposes, one of which is to analyze the statistics on the actual situation of "Rebuilt" and to make clear the difference of "Rebuilt" activities on the different regions. The second purpose is to find the main factors among the conditions which generate "Rebuilt" on each regions. Main findings obtained from analysis are as follows, (1) From the viewpoint of housing construction activities, 'Rebuilt' is very important situation on local regions. (2) In recent years, the ratio of "Rebuilt" has incresed all over the country, the activities of it on the East Japan is more active than it on the West Japan. (3) The ratio of "Rebuilt" has directly no relation to the stock of dilapidated houses on each regions. (4) The ratio of dilapidated houses is inversely related to the stage of urbanization on the each regions. (5) The ratio of "Rebuilt" to "destruction" varies among the regions. That figures are between 40% and 80% It means that the respectable housing lots after "destruction" are utilized for nothing or another uses except owned houses. (6) The differences of "Rebuilt" activities are dominated by the housing situation, especially the size of the housing lot on each regions.
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TETSUO TAMAI
Article type: Article
1978 Volume 266 Pages
143-150
Published: April 30, 1978
Released on J-STAGE: August 22, 2017
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5-3 Movements of Inhabitants in Machiyashiki 5-4 Factor of Inhabitants' Movements in Machiyashiki
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SHIGERU MARUYAMA
Article type: Article
1978 Volume 266 Pages
151-157
Published: April 30, 1978
Released on J-STAGE: August 22, 2017
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C. Itoh was one of the most famous "architects" in early modern ages of Japan. In this paper I picked out his view of architecture in his early architectural essays, and considered the start of his own "science" and "architecture" into "Japan". Contents, 1. Two contrary opinions on Nikko mausoleum by C. Itoh 2. His swift change from modernism to nationalism 3. C. Itoh as an active man of "Japanese beauty" of architecture 4. A fall of his view by his "Science"
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[in Japanese], [in Japanese]
Article type: Article
1978 Volume 266 Pages
159-
Published: April 30, 1978
Released on J-STAGE: August 22, 2017
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[in Japanese], [in Japanese]
Article type: Article
1978 Volume 266 Pages
160-162
Published: April 30, 1978
Released on J-STAGE: August 22, 2017
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