Original concrete, the source of supply for manufacturing recycled aggregate is generally composed of different types of original aggregate and different strengths of original mortar The properties of recycled aggregate exhibit a considerable variation due to the properties of original concrete. Therefore, at the time of mix lesign of recycled aggregate concrete, it is important to evaluate the use of recycled asrsrresrate concrete based on the quality of the recycled aggregate after having grasped the correlation between original concrete and recycled aggregate. From this point of view, this paper presents a series of experiments and subsequent analysis on recycled aggregate and recycled aggregate concrete as given below. 1. Using three types of original coarse aggregate and in a determined water-cement ratio, 12 types of original concrete were produced. Also. 12 types of recycled coarse aggregate were Droduced using with these original concrete. 2. Properties of the 12 types of recycled coarse aggregate were evaluated, and the correlation between the properties of original and recycled coarse aggregate was obtained. 3. 36 types of recycled aggregate concrete were produced, the properties of these concrete were tested, and recycled coarse aggregate was obtained. Much valuable information regarding useful results on the mix design of recycled aggrregate concrete was obtained through the experiments described above.

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The appearance of building materials changes with their moisture conditions of their faces. The wetting-color-tile, of which glazed surface is sandblasted, was developed. Following findings were obtained from the limited number of psychological and physical test. l)The tile with high lightness of color shows a little change in color by wetting. 2)The color difference dE* of wetting-color-tile is twice as great as that of non-elazed tile, by wetting. 3)The wetting-color-tile shows a more pleasant image than the non-glazed tile, by wetting.

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The stress transfer orooerties on the joining interface between concrete and GRC oanel used for parmanent form were studied. The compressing-peeling test was used in the expriment to examine the strain on the concrete and GRC panel of the test specimen. The compliance which was the delivative of strain defferentiated by stress, was proposed as a parameter to make clear the stress transfer mechanism on the joining interface. It was considered that the compressive load at which the slip and the peeling occured on the joining interface of the test specimen, could be evaluated by the behaviour of the compliance.

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For tall buildings and for buildings in which response control systems by hysteretic damping of steel are installed, it is important to understand inelastic response characteristics of buildings under wind loading. Inelastic response characteristics and response prediction method under across-wind loading were reoorted in the previous paper, Part 1. But, from the nature of across-wind loading, it was not confirmed how the mean wind loading and the low frequency component in wind force have an effect on the inelastic response. In this paper, inelastic response characteristics, e.g. the transition of the mean displacement, the distribution of the fluctuating displacement, the maximum fluctuating displacement, the absorbed energy and so on, under along-wind loading are investigated through time history response analyses by using a single-degree-of-freedom system. And, a stochastic method of estimating the inelastic response under along-wind loading, by extending the method for across-wind vibration, is proposed.

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Horizontal responses of tall buildings to wind are generally a narrow-band random process caused by the light damping of structures. The fundamental natural frequencies of structures are dominant in the time histories of responses. The traces of response are elliptical in shape. It is necessary to evaluate human perception of motion under conditions as similar as possible to those that exist in tall buildings. Although investigations have been conducted on the human perception of horizontal vibration in existing tall buildings, the relationship between the perceotion of random and sinusoidal motion has not been established. The authors first studied the human perception thresholds of uniaxial, elliptical and circular sinusoidal motions to discuss the effect of the two-dimensional motion. Secondly, we studied the perception thresholds of a narrow-band random process to investigate the effect of random motion. In this paper, the human perception thresholds of a narrow-band random process at predominant frequencies of 0.125Hz to 0.315Hz are examined and compared with those of sinusoidal motion. Statistical analyses were performed using the experiment data to propose probabilistic criteria for the perception thresholds.

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In recent years, elastic-plastic seismic responses of local stresses and defornations of individual structural members of tall and complicated framed structures have been analyzed. However, discussion on modal property of such detailed responses has not been presented before. This paper first presents a nodal method of analysis, which uses the mass condensation method, applicable to structures having numerous degrees of freedom and performing severe nonlinear behaviors. Secondly, this method is applied to examples of 2-15 storied framed structures. As a result, it is shown that for structures of about 10 stories and below the lst mode solutions are good approximations of overall responses, such as horizontal displacements of the top of the structures, and that for these same structures local responses, such as rotation angles of plastic hinges, can also be roughly estimated by the 1st mode solutions.

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This paper studies the damage reduction effect due to the basemat uplift of buildings which are subject to strong ground motions. First, I demonstrate a simulation analysis result of a slightly damaged building during 1995 Hyogo-Ken Nanbu earthquake, while it is located in Chuo-Ward and its surrounding buildings were heavily damaged. Drastic damage reduction was caused by the nonlinear soil-structure interaction effect due to the soil nonlinearity, neighbouring structures and the basemat uplift. Among those reasons, basemat uplift effects are studied by varing the shear wave velocity of the soil, the dimension, shape, and strengh of buildings, and the kind and intensity of input motions. In conclusions, the damage reduction would have been drastic for slender buildings whose foundation size is less than 15m, number of story is less than 15 during 1995 Hyogo-Ken Nanbu earthquake. However, the reduction extent is completely different due to the strength of building, the kind and intensity of input motions.

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Long-period microtremors were observed at 63 ooints in Kobe urban area after the 1995 Hyogo-ken Nanbu Earthquake. The purpose of the observation was to clarify the depth distribution of the base rock under the area. Using the observed records, horizontal-to-vertical soectral ratios were evaluated from cross-spectra of horizontal and vertical components and power spectra of vertical components. 0n the other hand, horizontal-to-vertical spectral ratios for the fundamental mode of Rayleigh wave were calculated from subsurface structure models with a different depth of the base rock. Comparing the two groups of spectral ratios, it was inferred that the base rock depth increases very sharply to about 1km on the south of the Rokko Mts. but the inclination becomes very gentle under Kobe urban area.

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Steel structure improvement method focusing on lateral drift using unit load method is presented. The concept of displacement participation factor which should be distinguished from sensitivity analysis is obtained from unit load method. Using the factor, the presented algorithm minimize the frame weight being satisfied with the deflection constrain and stress constrain simultaneously. With the method, this paper shows some example for high rise building, and the analysis result mention that the algorithm can be very useful for structural scheme.

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The present work discusses a formulation for geometrically non-linear control of axial forces of stings in beam string structures. A tensegrity or cable net, which is stabilized by prestressing, is usually very deformable, and the governing eauations for these structures become highly geometrically nonlinear. In this paper, a method to determine the prestresses to be introduced in the stings is proposed based on Update Lagrangian Formulation for the prestressing to satisfy the conditions of constrains. Moreover, controllability of the non-linear control is discussed based on the controllability gramian matrix such as linear control. The determinant of the erramian matrix as performance criteria takes a minimum value when the matrix is singular. When the gramian matrix is non-singular, the system is controllable and the forces of actuators are determined by using minimum norm solutions of general simultaneous linear eauations. The availability of the present method is illustrated by the numerical study.

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Distribution models and specified values of Young's Moduli of the structural timbers used for conventional construction were analyzed and reliability levels were obtained at serviceability limit states. And based on the current Working Stress Design, reliability levels were also obtained at ultimate and serviceability limit states. The results are summarized as folows: (l)Same safety levels as steel structures and 2×4 wood frame structures were gotten at serviceability limit states. (2)The current allowable unit stress in Building Law Enforcement Orders seem to be a little small from the point of view of the reliability level comparing to those of steel structures and 2×4 wood frame structures. (3)The values of Young's Moduli recommended by The Architectural Institute of Japan also seem to be a little small from the point of view of the reliability level. (4)Size effect couldn't be seen in the structural timbers used for conventional construction.

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This retort describes the process by which the authors derived an ultimate load bearing capacity formula based on yield line theory for various kinds of floor slabs with unidirectional slab bands. The authors conducted tests on slabs with two unidirectional slab bands as samples to verify their formula. Furthermore, a few model floor slabs were compared with the samples on the basis of elasto-plastic analysis. Slab thickness, width, number of rows, and the span ratio of the slab bands were varied as the load bearing characteristics of the floor slabs with slab bands were compared and studied in various ways.

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Equations to evaluate nonlinear Possion's effect of concrete are proposed, and those are incorporated into the orthotropic constitutive model. The Poisson's ratio of concrete becomes large with increase in comoressive strain. The tendency is remarkable for high strength concrete or under low confining stress conditions. Strains corresponding to the nonlinear Poisson's effect are atpplied as initial strains in order to avoid numerical difficulties. The applicability of the proposed method is examined through finite element analyses of triaxial coirroression tests with differences in the concrete strength and the amount of lateral pressure.

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The optimum elastic and plastic design methods of plane rigid frames have been proposed in many previous studies. But, they have not dealt with the ootimum design problem considering elastic constraints and plastic constraints simultaneously. In this paper, first, the limit analysis method is presented considering the axial force-bending moment interaction vield condition. Next, the optimum design method is suggested, in which the minimum weight design of a structure is obtained under the simultaneous constraints of elastic stresses, elastic story drift angles, plastic faqilure load factors and the strength ratios of column-to-beam. And, solving the optimum plastic design problem of a portal frame and the optimum elastic and plastic design problem of a 12 story frame, It is confirmed that this method gives the optimum design solution.

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Ths present paper investigates the effect of surface roughness of high strength bolt factional joints on slip resistance, as well as the relationship between surface rouehness and the slip coefficient. The main results are as follows: 1. Sufficient surface rouehness can be achieved without rust on the frictional surface using Shot or Grit Blast Process. However, adequate rust on the frictional surface is required for the grinder process. 2. The effect of surface roughness on relaxation is slight 3. A sufficient slip coefficient can be achieved without rust on the frictional surface by using the Shot or Grit Blast Process. 4. If no rust is present on the frictional surface, the surface roughness and slip coe伍dent correlate. However, if rust is present on the frictional surface, both the surface roughness and slip coefficient are limited.

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First, tension tests of 590N/mm^2 strength steels were carried out in order to examine effects of the vield ratio. Test pieces were exnerienced previously the large strain. And these results are comparison with results of ordinary test pieces. Secondly, effects of the yield ratio on hysteretic characteristics of high strength steel beams were examined under the incremental and the constant amplitude load. These results lead to the conclusion that these is no difference in the practical skeleton curve and the practical energy absorbing capacity of high strength steel beams, in spite of the difference of the vield ratio.

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The stochastic response of a large floating island for seaquakes induced by horizontally traveing seismic wave on sea bed is formulated, taking account of structural flexibility and fluidstructure interaction. The floating island is idealized as an elastic circular plate with or without tension-legs. Hydrodynamic pressure acting on the floating island is obtained in closed form on the basis of a linear potential flow theory. The response quantities are evaluated by a wet-mode superposition approach and stationary random vibration theory. Numerical examples are presented to discuss the difference in the response behaviors of the floating island against horizontally traveling and vertically incident waves.

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This paper presents the formal representation of seismic risk assessment (SRA) problems based on object-oriented analysis. SRA problems are divided into two parts; one related to the representation of SRA and the other which should be encaosulated in objects. Introducing objects and message sending concepts in object-oriented approaches, we propose an ontology of SRA reoresentation problems. We refer to it as an object-oriented ontology (OOO).Basic properties and risk structures with duality in SRA problems are explained in terms of OO0. Through the research, it is pointed out that polymorphism properties due to the duality hidden in SRA and the mixture of the above two parts become the cause of complexities in SRA.

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