Floors in residential buildings require performance assessment with respect to daily safety and comfortableness. This is especially important for floors in Japanese houses which are used without shoes, retirement facilities and rehabilitation facilities. For these aforementioned floors, the following performances are required:
 ·Floor stiffness during walking
 ·Titubation during walking
 ·Floor stiffness during activities where soles are not in contact with no-shoe-floors such as sitting and lying down
 ·Floor stiffness during collision when a subject falls down
  The following performances are standard for no-shoes-floors:
 ·Lightweight floor impact sound insulation property
 ·Walking floor impact sound insulation property
 In addition, with the aging society in Japan, the runnability of castor or a wheelchair is also becoming an important performance requirement.
 These performances are influenced by the deformation characteristics of the floor in the vertical direction. However, the degree of influence is not clear as it varies depending on the material of the floor and the construction methods. This needs to be quantified in order to appropriately specify floor coverings for new buildings.
 This research focused on identifying the extent of influence of certain floor materials and construction methods on the performance of floors. In addition, an investigation of the relationship between various performances and deformation characteristics was performed. The scope of the research involves floor coverings on concrete groundwork commonly used in Japanese residences including wooden floor, tatami mat, PVC sheeting and tiles and carpet.
 The methodology of investigation involved two stages. Firstly, 63 floor coverings with varying deformation characteristics were selected and sample floors were made by gluing these onto a rigid concrete groundwork. The performance value of each sample was compared to the evaluation of building users which was measured via methods including those established in past research and specified in the Japan Industrial Standards. The second stage involved the development of a device which can measure deformation characteristics via static loading. This device was used to measure the deformation characteristics of the samples and thus, relationships between these results and performance values were evaluated.
 In summary, it was found that the deformation of a specific point within a particular load region on the floor covering influences the performance of the floor in regards to daily safety and comfortableness. The relationship between various floor performances and the deformation characteristics of each floor covering was quantified. The results of this research can be effectively used by developers to appropriately specify floors which satisfy a range of floor performances.

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 Blind panels are often attached to the rooftop of a building along its perimeter to keep outdoor equipment from sight. Permeable materials are generally used in order to cool the equipment by winds. Furthermore, it is expected that the wind loads on such panels are smaller than those on solid panels. Previous studies of wind loads on blind panels mainly focused on solid panels. Few studies have been made of permeable panels.
The present paper investigates the wind force coefficients on solid and permeable blind panels installed on the rooftop of a high-rise building based on a wind tunnel experiment and a CFD simulation with LES, in which the porosity is changed from 0 to 80 %.
In Chapter 1, the background and objective of the present study are first described. Then, the previous studies of wind loads on blind panels are reviewed.
Chapter 2 briefly explains the wind tunnel experiment on the wind loads on blind panels attached to the rooftop of a high-rise building. In the experiment, perforated thin panels with porosity of 0, 20, 50 and 80 % are used for the blind panels. Considering the difficulties in model making and pressure measurements on permeable panels, the wind pressure coefficients on the rooftop near the panel are used for those on the panel's interior surface for evaluating the net wind force coefficients on the blind panel.
Chapter 3 describes the CFD simulation technique with LES applied to the wind tunnel experiments, in which the wind loads on and the flow field around the blind panels with porosity of 0, 20 and 50 % are investigated.
In Chapter 4, the CFD simulation technique is first verified by comparing the results with those of the wind tunnel experiment. A relatively good agreement between CFD and wind tunnel experiment is obtained.
In Chapter 5, the relation between the wind pressure coefficient on the rooftop near the blind panel and the panel's interior surface is investigated based on the CFD. Regarding the solid panels, large negative pressure coefficients are induced on the upper part of the corner. In such a case, the above-mentioned wind tunnel experiment may underestimate the design wind loads on the blind panels. On the other hand, the vertical distribution of wind pressure coefficients on the panel's interior surface is almost uniform in the permeable panel case, which validates the wind tunnel technique.
In Chapter 6, the wind force coefficients on the blind panels are investigated in more detail. The peak wind force coefficients on the panel ranges approximately +4 to -4 regardless the porosity. The results indicate that the wind pressure coefficients on the rooftop near the blind panel can be used for estimating the net wind forces on the panel except for the solid panel case. In addition, the mechanism producing large positive pressure coefficients on the interior surface of solid blind panel is discussed based on the visualization of the local flow around the blind panel.
Chapter 7 summarizes the main conclusions obtained from the present study.

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 A two degree-of-freedom (2-DOF) model is employed for mid-story isolation buildings or a tuned mass damper mounted on buildings in practical design. These systems are classified into a primary-secondary structural system. A seismic response analysis using this model is an empirical evaluation method in design practice. However, the accuracy of the peak response distribution computed by the 2-DOF model has not been clarified.
 The objective of this study is to investigate the error in the inter-story drift calculated by the 2-DOF model. The employed 2-DOF model is derived from its original multi-degree of freedom system (MDOF) based on dynamic reduction technique. Parameters of interest are a tuning ratio and mass ratio. The tuning ratio is a frequency ratio to secondary to the primary system. The mass ratio is a ratio of the secondary mass to the effective mass of the primary system. The mass ratio is set within the parameter of 0.02 to 0.5. The inter-story drifts in primary system are recovered from generalized displacements (modal displacements) of the 2-DOF model and classical modal vectors with respect to the primary system.
 A stochastic vibration analysis is conducted in both original MDOF model and corresponding the 2-DOF model. RMS responses are obtained by solving a Lyapunov equation governing the stochastic process. The displacement responses of the MDOF model are decomposed into coupled and decoupled components. The decoupled components are the higher modal responses. The coupled component is the remaining response and corresponds to a controlled response. The controlled mode is limited to the fundamental mode in this study. The response of the controlled mode is compared to the one from the 2-DOF model. The analysis reveals that the 2-DOF model estimates accurate floor displacements. The relative errors are ten percent at most. However, the 2-DOF model underestimates inter-story drifts in the upper story of the primary system. As the mass ratio becomes larger, the error becomes large.
 A convenient modal superposition technique is proposed to improve the accuracy of inter-story drift obtained by the 2-DOF model. The method is as follows. The CQC modal combination is applied with modal damping factors evaluated by classical modal vectors. Then, amplitude of the response is slightly corrected to be consistent with the one obtained from the MDOF model. It is confirmed that reasonable accuracy is obtained by the proposed method.

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 Recently, research and development on structural health monitoring (SHM) technology has been advanced for the purpose of proper maintenance and rapid diagnosis of disaster. In order to disseminate this technology, it is necessary to reduce the price of the whole system including installation and maintenance costs. One solution is to promote wirelessization of a system that makes it unnecessary to lay cables to each part of the building. In this case, there is a problem of how to secure the simultaneity of the data recorded with multiple vibrometers.
 In this paper, a simple method is proposed for synchronous correction of input / output waveforms recorded asynchronously in structural health monitoring. The main feature of this method is that by identifying the transfer function of the target building from the acceleration record and converting either the input or the output waveform by the transfer function, the accuracy of correlation evaluation (detection of synchronous deviation) between waveforms.
 In this study, applicability of the proposed method was verified by using multiple numerical examples in which pseudo synchronization deviation and noise were added, for two-story housing. Two estimation models of the transfer function were proposed, one with using 2 mass system model with the same degree of freedom as the target building and the other using 1 mass system model easy to handle, and compared the estimation accuracy. The noise of the input / output waveform was taken into account by adding independently generated band limited white noise to each waveform. The noise level (the ratio of RMS value of noise waveform to that of original waveform) was varied from 0 to 100%. The main results of this study are as follows.
 (1) Transfer functions of 1 and 2 mass system model were expressed explicitly with the variables of natural frequency and damping constant.
 (2) In the estimation of the transfer function, it was confirmed that the transfer function without synchronization deviation can be accurately estimated by identifying the parameter that minimizes the error with the above model with the amplitude ratio of the input / output waveform as the target. This is based on the fact that when there is a synchronization deviation between the input and output waveforms, the phase difference is greatly disturbed, while the influence on the amplitude ratio is small.
 (3) By estimating the transfer function using 1 mass system model, it was confirmed that it is possible to estimate the synchronization deviation stably and accurately even if there is noise in the recorded waveform.
 In addition, it was confirmed that synchronization deviation can be estimated with practical enough accuracy even by using seismic observation records of two-story real housing.

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 Recently, response control dampers are used to improve seismic response of high-rise building for long-period ground motion. In general, it is required to arrange the dampers efficiently with small number on the pane of high-rise building structure. However, it is not easy to obtain the optimum placement of the dampers on the plane of structure, because the damper's performance depend on the dynamic behavior of the building. Therefore, in this paper, a method to obtain an optimal placement of the response control dampers on the plane of high-rise building structure is proposed.
 In section 2, the proposed method is shown. In the present method, first, the dampers are placed on all possible places in the frame structure (ground structure) of the building (Fig. 1a), and then the dampers are gradually removed by evolutionary structural optimization (ESO) method (Fig. 1b～Fig. 1f). The accumulated damping energy of the damper in the dynamic analysis is used to determine the removal order. In the dynamic analysis, finite element method with numerical time integration method (mean acceleration method) is used. The dampers are modeled in dash-pot (Fig. 2 and Fig. 3), and the accumulated damping energy is shown in Eq.(3).
 In section 3, the effectiveness of the present method is shown. In the numerical example of the building with 3 layers and 3 spans (Fig. 4), it is shown that the optimum solutions can be obtained by the present method (Fig. 5～Fig. 8). In the numerical example of the high-rise building (Fig. 10), it is shown that the effective solutions are obtained compared with general placement plans (Fig. 11～Fig. 16, Table 1). Also, it is shown that the optimum placement obtained by the present method is changed by the types of seismic waves (Fig. 17). Therefore, it is necessary to use long-period ground motion for the analysis in order to obtain the optimum placement of dampers in high-rise buildings.
 It is concluded from these examples that the present method is useful for determining the placement of response control dampers on the plane of high-rise building structure at the structural planning stage.

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 Appropriate evaluation of the structural characteristics of joints is necessary in order to understand their horizontal resistance characteristics of traditional timber frames. For this purpose, it is important to create a simple joint model that takes into account hysteresis when the joint is subjected to cyclic loading, and to establish a suitable analysis method.
 We have developed a spring model that considers compressive strain inclined to the grain in addition to the friction characteristics of the wood in a joint, and we have proposed an incremental displacement analysis method based on that model. The model considers resistive components at contact surfaces inside the joint by decomposing them into directions perpendicular and parallel to the contact surface. We represented the resistance perpendicular to the contact surface using compression springs and assumed a slip-bilinear constitutive law. We represented the resistance parallel to the contact surface using shear elastic springs and Coulomb's sliders. When the joint deforms, the spring force due to compressive strain inclined to the grain changes, and so the maximum friction force also changes. The shear springs must also satisfy the constitutive law with respect to the changing spring force due to compressive strain inclined to the grain. In the past, we introduced the concept of an apparent shear stiffness with regard to the shear springs. Using this method, we found that the apparent shear stiffness does not depend on the shear elastic spring stiffness. This method required an iterative calculation in order to derive the apparent shear stiffness. Consequently, there is a problem when dealing with complicated joint shapes in that there is an increase in the number of contact surfaces and spring models, so that the number of iterations required for the calculation to converge also increases.
 In the present article, to solve this problem, we introduce a method of incorporating the constitutive law of Coulomb's friction for the shear spring directly into the stiffness equation. Fundamentally, the spring force rate for the shear spring depends on the elastic spring stiffness. If the shear spring continues to satisfy the constitutive law of Coulomb's friction as the joint deforms, the spring force rate for the shear spring must continue to satisfy the maximum friction force. Incorporating these relationships directly into the stiffness equation and solving the equation makes it possible to obtain the rate of change of various state variables. If the shear spring continues to satisfy the constitutive law of Coulomb's friction, the symmetry of the stiffness equation is lost and the degree of indeterminacy decreases.
 We conducted a cyclic loading experiment on a joint with a dowel in a construction comprising a column and a penetrating tie beam. The loading method was displacement-controlled repeated and reversed cyclic loading using a digital jack. The experimental results revealed restoring force characteristics, with slip-type hysteresis specific to wooden joints.
 We carried out an incremental displacement analysis based on the proposed method, and performed a simulation of the results of a loading experiment on a penetrating tie beam joint with a dowel and a mortise-tenon joint with a dowel. We compared the experimental and analysis results, and confirmed that the shapes of the hysteresis loops for strength and stiffness were generally consistent. When we compared the results of the present analysis with those obtained using the previous analysis method, they were the same. However, the number of calculations was drastically reduced using the proposed analysis method. These findings confirm the high validity and efficiency of the analysis method proposed in this article.

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 Pneumatic structure resists external force by increasing internal air-pressure. In particular, lenticular pneumatic structure are strongly sealed. With this structure it is expected that stress suddenly changes with volume change. For this reason, the supposition of internal air-pressure uniformity may lead to an unsafe situation. In addition, the setting method of internal air-pressure on the basis of structural behavior of lenticular pneumatic structure has not been established.
 This paper examined the parameters as aspect ratios of rectangular panels. Firstly, dynamic data was collected through wind tunnel tests using both a rigid and a flexible model for the purpose of understanding the wind pressure coefficient under strong winds and the dynamic behavior of fluctuating internal air-pressure. Next, a time-history wind response analysis was performed to evaluate the fluctuating internal air-pressure under strong winds, and then compared with the results of flexible model by the wind tunnel test. Finally, a methodology for setting the internal air-pressure was proposed based on the data obtained from the static and the dynamic numerical analysis.
 The results of these studies revealed the following. The wind tunnel test using the rigid model showed mostly suction pressure over the entire surface in all parameters. In addition, when the turbulence intensity of air flows increased, the average absolute value of the coefficient of wind force became small. In the wind tunnel test using the soft elastic model, volumes increased and internal air-pressure decreased because the entire surface experienced suction pressure. It was compared to the numerical analysis data using a potential-based fluid and the results of the wind tunnel test using soft elastic model. The numerical analysis value corresponded with the experimental value. Through method of setting internal air-pressure in the case of aspect ratio of 1, it indicated that setting internal air-pressure is possible by accounting for internal air-pressure and membrane stress under uniformly distributed load.

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 In this paper, a prerequisite for “Reuse System” is that building materials finish the design of the reuse part before production. This use is temporary space, indoor exhibitions, the store in commercial facilities. The characteristic of existing reuse systems are “lightness”, “rapidity” and “simplicity”, but existing reuse systems is not combined “The kind of the use material is minimized” with “The use material is convert to a wide variety of structural shape”.
 To solve this problem, I propose Crescent System. Crescent System is the structure that Crescent Parts were connected by the arms. The joint of Crescent System combines “Mobile joint with the arms” and “Unbonding joint with Crescent Parts”. Crescent Part is Aluminum extrusions, this basic shape is crescent-shape that was made in Major arc and Minor arc. This change of basic shape affects the small dimensions of Crescent System. I made the miniature. As a result of this, a wide variety of shape was able to formed by the arms and Crescent Parts only. This Crescent System was stable by the installation of the strings. This stable structure is String Crescent Structure (SCS). I did an experiment and analysis to study structure behavior of SCS. As a result of this study, the knowledges were shown below.

 *Shear transfer mechanism between Crescent Parts:
 (Non-separating) The tensions of the strings does not occur, and the bearing stress occur.
 (After separating) The tensions of two strings reduce the separating between two Crescent Parts, and bearing stress increase.
 *Bearing moment transfer mechanism between Crescent Parts:
 (Non-slackness) Compression force occurs to one string, and tension force to the other string. Bearing stress between two Crescent Parts is small.
 (After slackness) Slackness occurs to one string, and tension force of the other string increase. Bearing stress between two Crescent Parts increase too.
 *The change of Crescent part-shape influences compared rigidity, compression stress of the string and Crescent Part.
 *The selection of the hollow structure for Crescent Part influences the rigidity of SCS.
 *A mechanical role of arms contact to the bolts is only the reduction of deformation.
 *A mechanical role of the prestress of the strings is prevention of deformation by slide, stabilization of structural behavior and the increment of the rigidity and the load for the slackness of the strings.

 The direct joining between Crescent Parts is "Unbonding joint" to permit siding and separating. As a result, I expected that SCS shows the structure behavior different from the elastic continuum, and put the case that the experimental value is different from the analysis value. However, the experimental value accorded with the analysis value in “Load-displacement” and “Load-tension of the string”.
 The challenges for the future are as follows. When SCS is applied into a an arched form, the two material axes of Crescent Parts are not aligned in a straight line. This geometric problem may influence rigid reduction, the increase of the stress. To prepare for this, I examine the appropriate value of the rigid ratio of each material for Crescent Part. The change of the prestress installation process influences the position and the size of friction and the contact in "Unbonding joint". This phenomenon may make the prestress control difficult. To prepare for this, It is necessary to study the prestress installation process and joint detail of the string. These problem solution is the condition of the utility improvement of Crescent System.

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 Evaluating the degree of damage and the remaining strength of structures after an earthquake is an extremely important task. Finite element method (FEM) is useful for simulating the nonlinear behavior of concrete structures up to their maximum strength. Actually, FEM provides much information, even on a microscopic level, for phenomena such as stress, strain, and cracks in concrete. However, evaluating the degree of damage in concrete structures from various responses of respective elements obtained from FEM is not easy. A damage index that represents the degree of damage of the target structure derived from analysis results would be extremely useful for evaluating the remaining strength of the structure on a macroscopic level.
 Earthquake-induced damage to concrete structures is roughly classifiable into cracking of concrete, compressive deterioration of concrete, and yielding of steel. This study proposes two indices for the damage evaluation of concrete structures. They are defined using element responses obtained from a nonlinear finite element analysis. One is a weighted damage index that reflects the condition of concrete in compression. The index is calculated based on the plastic strain energy of each concrete element normalized by the absorbed plastic strain energy at the point of compressive strength of concrete. The index of each concrete element is weighted by its minimum principal strain and volume of the element. Then the indices of all concrete elements are averaged to obtain a unique damage index that represents the degree of damage to concrete in compression. The other index reflects the yielding and plasticization of steel. In the same manner as that for concrete, the index is calculated based on the plastic strain energy of each steel element normalized by the absorbed plastic strain energy at the point where the equivalent plastic strain becomes 0.01. The index of each steel element is weighted by its second deviatoric strain and the volume of the element. Then those indices are averaged to obtain a unique damage index representing the degree of steel damage. Each index represents no damage with a value of 0.0 and severe damage with a value of 1.0 or greater.
 To investigate the applicability of the proposed damage indices, nonlinear finite element analyses were conducted for a steel-embedded concrete column specimen and reinforced concrete test specimens of several types. Plane stress analysis and three-dimensional analysis are applied for reinforced concrete walls, columns and beams subjected to monotonic or reversed cyclic loading. These two indices, which represent the degree of damage to concrete and steel, increase along with the applied load. Results show that the damage index of steel is almost 1.0 when the specimen reaches its yielding load and the damage index of concrete is almost 1.0 when the specimen reaches its maximum load or temporary load drop point. Failure processes and failure modes can be evaluated from the growth tendencies of the concrete and steel damage indices.

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 A perfobond strip is a shear connector comprising a flat steel plate with a number of holes punched through it. Concrete flows through the holes forming dowels that act as shear keys, providing resistance in both vertical and horizontal directions. This connector was proposed by Leonhardt in Germany, and the composite effect of steel and concrete is very high due to the shearing resistance of the concrete in the holes. In addition, it is recognized as having high fatigue strength. It is widely used as a validated shear connector in various steel-concrete hybrid civil engineering structures, since it has high shear resistance and fatigue strength, and it has better constructability than other types of shear connectors such as headed stud shear connectors. Strength evaluation formulas for the design of these shear connectors have been proposed by various investigators around the world. A design formula was specified in the JSCE (Japan Society of Civil Engineers) Standard Specification for Hybrid Structures in 2009. In view of their excellent features, they are expected to be increasingly applied to connections in building structures. However, these connections are much smaller than those in civil engineering structures, so there is a need for a strength formula that accurately evaluates their force transfer mechanism, such as their restraint stress.
 This paper proposes a modified formulation for ultimate shear strength considering the restraint stress of concrete in these connections, based on the new author's proposed formulations for ultimate and residual stresses under restraint stress to the contact surface under friction and the bonding behaviors of various contact surfaces between steel and concrete. This formulation provides ultimate shear strength by multiplying shear cracking strength by the ratio of ultimate shear strength to shear cracking strength, considering the effect of restraining concrete around the steel plate hole by reinforced concrete cover and penetrating rebar. This formulation includes a new effective area of restraint part and an effective width of RC-cover part. Predictions from the proposed formulation almost agree with test results.

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