Strength difference of high strength concrete between the strength in structures and the strength of standard cured specimens was investigated from the results of field experiments. Mock-up columns were fabricated in the field experiments with a cross-section of from 750 by 750 mm to 1000 by 1000 mm, and the compressive strength of cores drilled from mock-up column were compared with the strength of standard cured specimens. To confirm the influence of materials, 3 types of binders and 5 types of aggregates were examined. The water- binder ratios were varied from 0.20 to 0.45. It was found that the difference between compressive strength of specimens and that in structures was influenced by the kind of binder, the maximum temperature of the columns, and the water-binder ratio.

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The effect of kind of structural members and construction seasons on distribution of compressive strength and strength development of concrete in structures made with high-strength concrete were investigated based on many data from full-scale experiments which were carried out for past about 15 years. The results are summarized as follows: (1) The strength development of concrete in structure from 28 days to 91 days in summer is smaller than that in winter. (2) The ratio of compressive strength of 91 days core specimen to 28 days standard-cured specimens is nearly equal in columns and column-beams joints, but about 96% in beams and about 90% in slabs.

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It has been pointed out that bisphenol A has possibility to be one of the endocrine disruptors. It is considered that bisphenol A is included in epoxy resin minutely; therefore, it is essentially important to know how much amount of bisphenol A is eluted from epoxy resin adhesives for construction works. In this context, quantitative analysis of bisphenol A eluted from two brands of commercial epoxy resin adhesives for construction was conducted in the study. The results obtained can be summarized as follows; 1) 0.1x10^<-6>grams and 11x10^<-6>grams of bisphenol A were eluted with acetonitrile from 1 gram of the two brands of uncured epoxy resin adhesives, respectively. 2) 0.030x10^<-6>grams and 0.017x10^<-6>grams of bisphenol A were eluted from 1 gram of the two brands of cured epoxy resin adhesives with 60℃ water. 0.077x10^<-6> grams and 0.064x10^<-6>grams of bisphenol A were eluted from 1 gram of the same cured epoxy resin adhesives with 60℃ alkaline water.

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The slipperiness of inclined floors is very important performance item for human from a viewpoint of safety in every movement. In former report, anthers presented the method to evaluate the slipperiness of inclined floors in going up and down and changing direction. In this report, anther present the method to evaluate the slipperiness of inclined floors in going across, dealing with the coefficient of slip resistance, C.S.R・Li, detected by slip meter named "O-Y・Pull Slip Meter" developed by auther et. al. Finely, auther present the method to evaluate the slipperiness of various inclined floors generally in every movement such as going up and down, going across, changing direction and in every factors such as sex, age, shoes.

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The author has proposed Rocking Center Designated (RCD) Mechanism and RCD structure to control the vibration modes of building structures. As a practical example, displacement distributed structural system and its use in structure design is discussed in this paper. The proposed system is simplified as a SDOF model that can also represent the main characteristics of ordinary structures including base isolation. The benefits of the new structure system are a more easily increase of the predominated period, a rational displacement distribution satisfying the performance needs, and a more economical energy absorption scheme at the first story using hysteric dampers. The new structure system is also expected to be a new strategy for eliminating earthquake damages of soft first story buildings.

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In seismic isolated buildings with laminated rubber bearings and elastic sliding bearings, the former plays the role of isolators and the latter the role of dampers As the bearings that support the weight of superstructures are the mixture of isolators and dampers, lateral stiffness of the isolators varies due to the variation of yield strength of the dampers First, a method to predict the response of this type of structures based on the energy balance theory is introduced in this paper Then, time-history response analyses are carried out to verify the method Next, the optimum characteristic values of the isolation system are calculated using the method It is intended to evaluate the influences of various characteristic values on the response and to show the essences of design methods for this type of seismic isolation system.

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The closed form equations for equivalent linearization method are presented. In velocity response spectrum constant region, the response ductility is the function of yielding strength, yielding deformation angle and height of structure. But in acceleration response spectrum constant region, yielding deformation angle and height of structure is irrelevant to response ductility. And in deformation response spectrum constant region, yielding strength is irrelevant to response ductility. It is shown that these characteristics are essential by the discussion based on energy balance of stationary random vibration. The evaluation method for probability of failure during design lifetime, which is examined by deformation capacity is also presented. The closed form equations, for equivalent linearization method are utilized in above equation. The influence of variation of deformation capacity is considered in correction coefficient.

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Laterally loading test is developed in which horizontal forces are applied to a pile at depths below the ground surface. Field tests are conducted on steel pipe piles to compare the proposed method with the conventional one in which horizontal force is applied to the pile head. The proposed method is proven to be effective for estimating p-y relation below the ground surface. Based on the test results, a p-y model is presented. A static analysis using the proposed p-y model can well simulate the distribution of bending moment and displacement resulting from both tests conducted in the field.

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This paper describes mainly below; 1)Evaluation methods of the rigidity and the strength of the wall which is made of the steel plate reinforced concrete structure(SC) subjected in-plane shear was proposed. 2)Experimental study of the steel plate reinforced concrete structure (SC) was carried out. And the evaluation - methods were proved to be good applicable to the SC wall.

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The present paper studies the effects of the intermediate loads along members on the ultimate strength, that is, elasto-plastic buckling strength of single layer lattice domes and proposes an effective method to evaluate the buckling strength based on column buckling strength for members which is used to size the member sections. The method is based fundamentally on a concept of column buckling strength in terms of generalized slenderness that includes the effects of shell-like buckling with nonlinear effects before ultimate loads. The results presented in the paper confirm that the proposed method works well for the estimation.

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This paper presents the fundamental earthquake response characteristics of 2D wooden-framed house models with eccentric shear walls. The effect of increase of the wall ratio, of which the wall is perpendicular to the eccentric direction, on the torsional vibration control is examined. When the house models are subjected to earthquake input motions, the damage levels, which are prescribed by the ductility factors in advance, are also presented as parameters of the eccentric ratio and wall ratio of the models. It is found from the results that it may be seen almost 50% contribution of the tortional vibration to the total response quantity. When the eccentric ratio is larger than 0.2 or 0.3, the ductility factor responses remarkably increase. In case of the model with one axial eccentricity, the ratio Re≦0.5, if the wall ratio of the model has twice as much as the wall of the other eccentric direction, then the damage level will be almost the same to the one of the non-eccentric model.

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Since the Great Hanshin Earthquake, the demands of people who own buildings have changed: they want to use the buildings again with small repair cost. This requires good reparability of RC members. A beam with diagonal reinforcements is very ductile, however, the diagonal reinforcements yield on the tension side only because concrete struts will work with them on the compression side. When the diagonal reinforcements yield under tension, tension stress is applied to the concrete along the whole length by bond stress. This increases the number of concrete cracks. The results of this experimental investigation demonstrated that debonded diagonal reinforcements are an effective means to reduce damage to short beams and have the same energy dissipation ability as bonded ones.

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The objective of this paper is to examine the relation between the change of mechanical characteristics of structural frame due to an earthquake and the damage level of structural members. A part of the reinforced concrete frame is considered, and the story shear-relative displacement relation is analyzed in association with the damage level. The correlation between the story-stiffness and the relative displacement under lateral loading is clarified. Furthermore, it is pointed out that the rotation angle of column-base is highly correlated with the relative displacement. Based on the numerical analysis, the methodology of the reliable structural health monitoring system is indicated.

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When reinforced concrete members are subjected to bending moment, rotational deformation occurs in their ends. That deformation is generally considered to result from a slip of longitudinal bars, and some methods to estimate the rotational angle have been proposed. On the other hand, although a phenomenon that the members subside into the beam-column joints is observed, it has not been investigated. In this paper, it is insisted that the deformation results from a reciprocal action of the subsidence and the slip. A model to estimate the rotational angle considering the subsidence is proposed, and it gives good agreement with test results.

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This paper proposes a method to estimate the maximum displacement response of reinforced concrete buildings in an earthquake using the response spectrum. Nonlinear earthquake response calculations of 12,600 systems were carried out for 20 ground motions. The results were classified by using the dimensionless parameters based on properties of the system and the frequency characteristics of the ground motion, and plotted in the relation of the dimensionless parameters, strength ratio SR and displacement ratio DR. This relation was fitted by the hyperbolic curve for each plotted figure and the estimation equations (3) and (8) were proposed. This estimation showed satisfactory results in safety side.

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The objective of this paper is to study the shear softening characteristics of reinforced concrete deep beams. A mechanical model for the macroscopic shear failure is developed, focusing on the entire load-displacement relation. The method makes use of rotating smeared crack model and truss model, combined in a simple model. The analysis employs the development of multiple diagonal cracks and macroscopic shear crack propagation. The model is found in good agreement with experiments. The analytical results point out that the shear softening behavior strongly depends on the size of specimens, the shear-span ratio, the transverse reinforcement and the confinement.

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A macro model is devised and equations are derived to estimate load-deformation relations of cantilever pre-cast PC beams assembled by pre-stressmg to columns with deformed tendons, under assumptions of compatibility conditions between compressive concrete deformation and tensile PC tendon deformation composed of slips out of column stubs and elongation in plastic ranges of the beams The analytical load-deformation relation and the plastic region of PC tendon on the basis of the proposed model predict closely experimental ones obtained previously. Furthermore investigations, however, on deformation compatibility conditions, bond stress-slip relations of PC tendons and stress-strain characteristics of compressive concrete of PC beams, etc are needed.

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Many beam-to-column connections sustained brittle fractures in the 1995 Hyogoken Nanbu earthquake.This paper assesses the minimum criteria for which beam-to-column connections can be sufficiently transferring beam webs bending moment to column flanges for through diaphragm. Local buckling of haunched and non-uniform section beam-to-column connections have been analyzed to evaluate the collapse mechanism, Then a classification and a flowchart for designing on the basis of tests results obtained after the earthqauke.

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The experiments in this report are planned to clear the elasto-plastic behavior and establish the estimating equations on the ultimate strength of exposed-type column base with variable axial force Consideration is done on hysteresis charactenstics and strain states of experimental results As the result of consideration, the elasto-plastic behavior and the estimating equations on the ultimate strength of exposed-type column base with variable axial force are proposed The proposed method can explain the experimental results.

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This system truss has the mechanism to induce the high bolt clamping force Thus, the initial clamping force reduces the stress range in the bolt under applied cyclic loads and so improves the fatigue life Moreover, to improve the fatigue properties of space trusses, this paper describes the fatigue tests of the single-bolt joints of system trusses conducted on actual connection models The test variables are the size (M30, M42), the manufacturing process (rolling and machining) and the stress ratio of the joining bolt And, for practical applications, the results are presented the S-N diagrams described by the stress range and the fatigue limit diagram As a result of the tests, the bolt produced by thread rolling after the heat treatment has the better safety against fatigue than that produced by thread rolling before the heat treatment, thread machining and so on There is remarkable difference in the fatigue limit by the stress ratio of the joining bolt produced by thread rolling after the heat treatment And the fatigue design formula can be led from the lower bound by which the 95% confidence level was shown.

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Structural control has paid much attention to seismic design to relieve the damage of moment frames even against strong ground motion. As one of the passive structural control system, hysteretic dampers are widely used recently in Japan. This paper proposes the formulation of modeling of the multistory planar moment resistant frame with hysteretic damper system to fishbone-shaped frame without numerical analysis such as push-over and so on. This model can predict the earthquake response such as story drift, cumulative plastic deformation of member for the seismic response analysis of the passive structural control system. It is important to estimate strength and stiffness of damper system for the modeling of moment frames with hysteretic damper, because the earthquake response of the moment frames with hysteretic damper is largely affected by the strength ratio and stiffness ratio of the damper system to the moment frames. And the propriety of the modeling is presented by numerical examples.

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This is a study on the cumulative damage of steel members caused by seismic response. Miner's law is accurately applicable to the seismic response of the steel members which this study covers. Generally maximum amplitude law is convenient and practical, however it is too biased to the safer side to apply to the seismic response of small amplitude. The ratio of the cumulative damage value by the Miner's law and that by the maximum amplitude law is very related to the time passed of earthquake ground motion. This study corrects the maximum amplitude law by experiments and analyses.

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To develop a rational stability design method for a rigid multi-bay multi-story frame with slender columns, inelastic buckling load of unbraced frame dominated by single buckling of column is studied. We proposed the method for a single buckling of the column elastically restrained by other members is derived for simplified models by the previous paper. In this paper, we applies the proposed method for the elastic frames to the inelastic frames. Through analytical and numerical studies carried out, the condition that the column buckles prior to the frame instability is investigated. Applicability of the proposed method is also demonstrated and discussed.

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Development of performance based design in US and Japan during the last decade was reviewed, from which it was ascertained that performance based design relies on common knowledge between designers and customers on building quality associated with cost by means of comprehensive description for performance levels The performance description is required to be meaningful for users, identifiable with damage, and quantifiable on limit states This paper attempted to propose such performance description satisfying the three requirements for steel structural buildings Performance was categorized into five levels, i e, functional, undamaged, reparable, life safe, and collapse Each level was visually illustrated for the sake of easy understanding for building users

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In the H-shaped steel girder filled with concrete in its both concave sides (CFH), the additional filled concrete weight raises the total steel amount of the building structure But in Europe, CFH beams have been applied with concrete reinforced as RC structural member The reason is considered that the following merits' weight is great, fireproofing protection is unnecessary, sub-beams are unnecessary, environmental vibration performance has advantage, etc The object of this study is the CFH beam filled with concrete including only studs and weld-steel-mesh In this paper, the evaluation method for the stiffness and strength of the CFH beam is proposed, based on the experimental results

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