In recent years, it becomes necessary to estimate the workability and consistency with good accuracy. Main purpose of this study is to establish a rheological model of fresh concrete that can consider the properties of dilatancy. Fundamental experiments using coaxial cylindrical rotation rheometer were carried out on the behavior of fresh mortar. From the visualized experiment on the inside of fresh mortar, it was clarified that there is some complicated deformation in the fresh mortar. Also, from the measurement of shear stress, it was demonstrated that rheological properties of fresh mortar are greatly influenced by the change of shear stress which is thought to be caused by the dilatancy. Further, a strong relationship was clarified between the amounts of change in shear strain rate and shear stress.

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This study focused newly developed artificial high strength light-weight aggregates consisting of coal ashes and shale fine powders which enable us effectively to consum a large amount of the former in concrete.This research involves an experimental examination of strength characteristic and durability of concrete incorpotating the developed aggregates.As a result, the compressive strength of concrete with water to cement ratio of 30% showed an excellent strength characteristic of 84.6-89.4N/mm² at the 91day age. The compressive strength of the concrete air-cured in 20°C•60% humidity condition form three day age following sealed curing showed almost the same value as the strength in water cured. This appears the developed aggregates enhanced long term cement hydration due to those absorbed water. Futhermore, drying shrinkage and carbonation depth of the concrete showed smaller than normal concrete. Freezing-thawing resistance of the concrete was also improved by dry curing before this test.

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Compressive strength development of concrete is essential for cold weather concreting. It is well known that strength development of concrete under the freezing point is much delayed. But the evaluation method has not been shown clearly yet. Therefore when average outside air temperature is under the freezing point planning method of cold weather concreting is not clear. We focus on the concept of equivalent maturity method proposed by Sudo, attempted to propose a time-temperature function representing the strength development of concrete under sub-zero temperature. As a result, we have proposed a function to calculate the maturity under sub-zero temperature. The proposed function could explain the strength development of the concrete exposure in winter.

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The purpose of this research is to develop the design support system that can select the material composes the exterior wall of the building optimally based on the demand performance. Various performances like safety, durability, and livability, etc. are demanded from architects, builders and users for the exterior wall. The trade-off relation such as a superior one in a certain evaluation index is judged inferior in another index occur under multiple evaluation indices. In this research, the exterior wall of the building is described as a planar stratified that is composed of combination of board materials. As a result, the material selection system applied Genetic Algorithm (GA) can derive the appropriate solution with plural performance criteria.

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Recently, rooftop gardens, wall greening and greening around buildings have increased especially on buildings and infrastructures in urban areas. When we plant contiguously building structures it is necessary to make sure that these are not damaged by the plants, because roots can be a serious external force for building materials. The roots penetrate spaces or weak portions in building materials and then subsequently become enlarged in them. To prevent such damages, it is necessary to know the behavior such as the extent of possible enlargement and the expected enlargement force. An apparatus was therefore developed to characterize the extent of enlargement and the enlargement force of the root. We measured those of the root of the cherry tree in this study. It was found that the root enlarged 0.17 mm in diameter in two months observation and the enlargement force increased to approximately 270 N in three months observation of summer. In addition, it was found that the enlargement force tended to decrease from sunrise to approximately mid-day and increase after mid-day to mid-night because of plant transpiration. In winter the enlargement and enlargement force were slight.

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Urban landscape is composed of the continuous accumulation of exterior finishing materials used for buildings. In the design of the buildings, the exterior finishing materials are selected in consideration of the “performance value” peculiar to the materials, the “space value” determined by economic consideration of building locations and the “environment value” based on regional weather conditions and atmospheric environmental conditions. From the investigation results, the tendency for selection of the typical floor's exterior wall finishing materials in Japan and the similarity by agreement degree between both areas are made clear.

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Vulnerability functions for wooden buildings are proposed, which employ a probability distribution model of seismic performance. An acceleration response spectrum is used as input to the functions. The probability distribution model is formulated based on two indices of seismic diagnosis data: stiffness and resistance force, and it is clarified that the bivariate normal distribution is a reliable model. Regarding estimation accuracy, the proposed functions are compared with experience-based vulnerability functions in past literature for three earthquake disasters. The proposed functions indicate fairly good accuracy when proper parameters of stiffness increase and resistance force increase due to non-structural walls are used.

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An evaluation method of the response of a pile due to an earthquake for the seismic design of medium-rise buildings is investigated based on the analysis with a three dimensional frame model considering soil-structure interaction. The effect of embedment of a structure on a story shear forces, the seismic coefficient for the foundation and the pile response are examined first. The effect of inertial and kinematic interactions on the pile stresses is then evaluated by the so-called seismic deformation method that is frequently used to estimate the response of piles in the practical design. Finally, the effective method for superposing pile response due to inertial and kinematic interaction are discussed.

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A tuned mass damper (TMD) using a rotational inertia mass has been developed to reduce vertical vibrations of beams and slabs subjected to walking excitations and earthquake motions. The newly developed TMD is composed of a spring and a ball screw mechanism with a fly wheel. Vibration tests of a beam structure were carried out to show the effectiveness of the TMD using a rotational inertia mass and compare the test results with those of simulation analyses using a theoretical model.

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Dynamic behavior of buildings allowed to uplift is investigated by means of classical modal analysis of a uniform shear-beam model on a rigid ground. The equations of motion are derived and eigenproblem is solved to investigate the modal properties during uplift. Free vibration under gravity during the first excursion of uplift is analyzed to show the responses of transient uplift behavior. In addition to the confirmation of significant reduction effect, it is pointed out from the results that the relatively complicated uplift responses at a glance can be recognized as natural consequences of higher modes' properties and their behaviors.

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Recently, various kinds of viscoelastic dampers are used for the vibration control of buildings. Some materials have complex properties concerning temperature, frequency, and strain dependency. Although many constitutive models of them have been proposed, most of the models treated these dependencies independently. Models that can consider these dependencies accurately are very limited, because it is very difficult to develop these accurate models since high mathematical knowledge and heavy studies are essential. In this paper, a simple and practical method to calculate the constitutive model considering these dependencies for the time history analysis was proposed, using the interpolation method of experimental data and the transform method of frequency dependent data to the time domain. The efficiency of the method was confirmed by the comparison with both the experiment results and more accurate model results.

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A set of reduced models of structures and wind loads is proposed for a high-rise building under time-dependent wind loading. A reduced structural model is constructed first based on an inverse problem formulation in terms of fundamental eigenfrequency and eigenmode. Then a reduced model of time-dependent wind loads is proposed by requiring the equivalence of displacements at representative nodes in the frame model and the reduced model without inertial and damping terms. These reduced models are applied to both the bare frame and the frame with high hardness rubber dampers. The validity of the proposed reduced models is investigated by the comparison with the results by the time-history analysis for an original full model.

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Recently, the environmental impact has been required to be explicitly taken into account in a life cycle design of building structures besides the initial economical efficiency, which has been ordinarily required up to the present days. Consequently, it is important not only to design the building structures so as to be safe as well as economical at the initial stage of completion of the building but also to pay attention and take into account the total behaviors of the designed and constructed building structures during all stages of their life cycles. The former paper by the authors has proposed the way to deal with the life cycle design of building structures with consideration of a hierarchy according to the ranks of building construction systems by using genetic algorithms as the optimization scheme with respect to both ecology and economy for evaluations. However, there is various uncertenties in a life cycle of building structures, therefore it is necessary to expand it to the life cycle evaluation that considered those uncertenties. In particular, the effect caused by earthquakes which occurs during the evaluation period should be investigated. Present paper proposes the way to realize the life cycle evaluation of building structures with consideration of seismic hazard, and investigation of possible necessity of its effect is carried out through numerical examples.

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The scheme of computational morphogenesis for the shell structures with free curved surface is proposed, where shape and distribution of thickness can be simultaneously optimized. Generally, when nodal coordinates and shell thicknesses of finite element are adopted as design variables in structural optimization problem, computational cost generally becomes very large. In the proposed scheme, distribution of thickness is discretized according to the nodal points, and NURBS (Non Uniform Rational B-Spline) is utilized by which the number of unknowns can be controlled while the high degree of freedom for expression of the shape of the curved surface as well as the distribution of thickness are maintained. Consequently, the problem in question has been mathematically formulated as strain energy minimization problem where coordinates of NURBS control points with respect to both the shape of the curved surface and the distribution of thickness are adopted as design variables and numerical examples are presented where the effectiveness of the proposed scheme is investigated.

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We, in this article, propose a manual strength calculation method of single bolted timber joint for end member joint loaded perpendicular to the grain. The strength calculation method takes into account the edge distance, the end distance, and the slenderness ratio as the parameters. The validity of the proposed calculation method was confirmed by the experimental results, edge distance of 1d · 2d · 4d · 6d · 7d, end distance of 1d · 2.5d · 4d · 7d · 10d, slenderness ratio of 3.75d · 7.5d · 10d.

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It is important that dynamic performance of bearing walls is elucidated for aseismic capacity of timber structures. Therefore resistance of bearing walls becomes important. I report this article about Influence of pullback loading by constant speed on shear properties of nailed wooden bearing walls. And I paid my attention to resistance of bearing walls in small defomation and based on experimental result I evaluated six phenomenon.

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This paper introduces a new structural identification technique using Variable Pendulum Sensor (VPS) for seismic evaluation of existing wooden house. Shifting the swinging cycle of the pendulum duplicates the equations of motion of the structural system including VPS, and makes it possible to directly estimate physical dynamical parameters such as mass, stiffness, and damping coefficient of the structure. To evaluate the performance of VPS, a series of numerical analyses are conducted. Result of the analysis shows that VPS can successfully estimate the physical dynamical parameters of multi degree of freedom structural system.

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The article was mainly composed of the three approaches- stress distribution by the finite element method, mechanical model based on fracture mechanics and basic beam theory, and the experiment whose parameters were size effect, the ratio of bending moment and shear force, hole size, and the arrangement of the hole. We, in this article, propose a manual strength calculation method of the timber with..circular hole taken into account the size effect, hole size, and the ratio of the bending moment and shear force as the parameters. The validity of the proposed calculation method was confirmed by the experimental results.

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The pile cap is the very important member connected with column, footing beams and pile. As vertical members, these are two kinds of member, column and pile, in a pile cap. So, the seismic behavior of pile cap is much complicated than the beam column joint. The experiments on the reinforced concrete interior pile cap which were composed of one column, two footing beams and one pile were carried out under cyclic loadings.
In this paper, the effects of the axial force of column and the volume of pile cap on the seismic behavior, e. g., the process of damages, failure mechanism and the ultimate strength of pile cap, are described.

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This research leads the theoretical solution of crack width in reinforced concrete members based on the equilibrium of axial forces and compatibility conditions between concrete and reinforcement and the condition of crack occurrence. In the case of bi-linear bond stress - slippage relationship model, the theoretical solution of crack width is led as the relationship between loaded end strain of reinforcement and crack width. The pullout bond test and tensile bond test is conducted to investigate the adaptability of proposed method for deformed steel bar and AFRP reinforcement. The calculated relationship between reinforcement strain and crack width shows a good agreement with the experimental result.

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Nine-Parameter Model predicting ultimate strength of reinforced concrete beam-column joints proposed by the auther is applied to establish a new seismic design method of beam-column joints in moment resisting frames designed by the weak beams-strong columns concept. The objectives of the seismic design are (a) to gurantee flexural capacity of the beams derived from flexural theory and (b) to preclude premature failure of the joint due to crushing of concrete. A set of design equations is proposed which includes requirements for the upper limit for the amount of longitudinal reinforcement as well as required amount of auxiliary reinforcement. The prediction of the design equations are compared with the prediction by the current design provisions derived empirically based on joint shear failure capacity. The current design methods are criticized with respect to their scope and the reliability.

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This paper presents the result of full-scale test of site welding beam-to-column joints with the method of drilled flange and threedimentional elastic-plastic finite element analysis. Based on the test result, the method of drilled flanges have large deformation capacity as compared with common site welding beam-to-column joints. In stress ratio is over 1.05, deformation capacity of the specimen which was used the method of drilled flange improved over two times larger than that wasn't used the method of drilled flange. Based on the analysis result, in case that the hole position is too near to column face, the method of drilled flange can't decrease stress concentration of the scallop part. So we should plan hole position is 0.75 times as long as flange width.

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No actual data based on observations is available for high-rise buildings subjected to long-period ground motions. A series of shaking table tests on a high-rise building are conducted in order to acquire realistic data on the damage. A proposed test specimen consists of a lower part represented by four-story steel frame structure and an upper part simplified by substitute layers made of concrete mass and rubber bearings. From preliminary vibration tests, the equivalence between the test specimen and a prototype building is verified in terms of the first three mode periods and corresponding mode shapes. The test specimen when subjected to a long-period ground motion exhibits cumulative inelastic deformations more than four times that expected in the seismic design, while the maximum story drifts remain nearly the same as that considered in the design.

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Aluminum extruded inlaid panels were researched as structural wall elements. Basic unit panels consists of six extruded box section parts that inlaid in together. Both side of the basic panel can be united with another unit panels in direction of width. Structural rigidity and strength on walls using this system were investigated experimentally. As a result, the following conclusions were obtained. Strength and rigidity of the unit panel were able to evaluate as sum of an individual extruded parts performance, but rigidity was estimated considerably low. Effect of connecting unit panels in the direction of width for the rigidity was accepted, but it was not recognized for the strength. When adhesive bonding was used together, the rigidity of panels become near the panels that are integral, but static strength of the panels depends only on bonding strength.

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A sustainable building steel structure system, which is kind of damage-controlled structure, consists of columns, beams and newly developed connections with buckling-restrained braces like knee brace. The columns and beams are connected with special long steel bars alone, facilitating demolition of the structure and able to be reused the members. Since the connections of beam-to-column are semi-rigid, the columns and beams suffer no damage. The buckling-restrained knee braces only absorb seismic energy. In the past studies, full-scale tests of the connection were carried out. Based on these results, structural models, which modeled the connection were analyzed and a mechanical model for the sustainable building structure system was established. In this paper, a structural design method is proposed on the previous experimental and analytical studies. The detail design method for the newly developed connections with buckling-restrained braces is established. A trial design is conducted where applicability of the design method is shown.

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