The authors have carried out experiments to identify the effects on fluidity, separation resistance, strength, Young's modulus, drying shrinkage and durability of high-strength concrete when sand-total aggregate ratio was varied. In high-strength concrete while water-cement ratio and cement-paste volume was fixed, that is, volumetric ratios of coarse aggregate and fine aggregate were varied.
 Three types of cement, normal portland cement, moderate-heat portland cement and low-heat portland cement, were used. Limestones and sandstones were adopted as coarse aggregate. Water-cement ratio was fixed as 35%. Unit water content was fixed as 170kg/m³.
 Analysis were carried out in concern with properties of fresh concrete, properties of concrete hardening, and tendency of properties of concrete where sand-total aggregate ratio was varied.
 As a result of the experiments, If sand-total aggregate ratio is smaller than general range, impression of state of fresh concrete tends to be somewhat impaired, but even if sand-total aggregate ratio is somewhat larger than general range, impression of state of fresh concrete is it was not compromised. However, when sand-total aggregate ratio is large as addition rate of high-performance AE water-reducing agent is significantly large, impression of state is impaired due to separation of fresh concrete in addition to increase in bleeding and delay of settling-time. In hardened concrete, influence of sand-total aggregate ratio on compressive strength is small, As sand-total aggregate ratio is larger, tendency of young's modulus to slightly decrease, tendency of length change by drying to slightly increase, tendency of carbonation depth to slightly increase.
 Based on the above, high-strength concrete may possibly obtain hardened concrete of required quality even if sand-total aggregate ratio is increased somewhat within range where separation resistance is not impaired in consideration properties of fresh concrete.

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 Large amounts of waste contaminated with radioactive substances were generated, posing an urgent problem of its disposal. Techniques to safely and surely contain radioactive substances have been developed, with specific proposals having been made. However, due to the necessity for temporary storage of radioactive substances until final disposal, research is under way regarding containments for that purpose.
 Meanwhile, the shielding performance of heavyweight concrete has long been known. Heavyweight concrete is a type of concrete made using heavyweight aggregate with an oven-dry density of over 3.5 g/cm³ to increase its density. Research and development for safe containments made of heavyweight concrete to store radioactive contaminants has been in progress due to its excellent shielding performance. Products developed so far have been mostly thin and small to facilitate transportation. However, such containments are rather required to be robust with high structural capacity and resistance to moisture migration so that they would cause no problem when piled up in layers to store a large amount of waste for a long time in a limited area. When assuming an environment contaminated with radioactivity, quick construction of such containments is also necessary. It is therefore essential to produce them as precast concrete products.
 For such precast products, aggregate with an even higher density is used to enhance their shielding performance while keeping a normal member thickness. It is then required to impart segregation resistance to such concrete to prevent segregation during production. It is also preferable to increase the self-compactivity in view of the ease of placing. In consideration of these requirements, the authors developed box culverts made of heavyweight concrete with a high segregation resistance and medium fluidity. These culverts can be made into large-scale containments by jointing multiple units using prestressing steel and waterproofing the joints and internal layers.
 Another requirement as important as shielding performance for a containment is the capability of completely eliminating leakage of contaminated waste to the environment for a long time. However, concrete involves a risk of cracking, and the risk is increased by drying-induced paste shrinkage and temperature-induced volume changes, particularly when the containments are placed on the ground, instead of being embedded, as is often the case with temporary storage containers. Water-resistant coating is applied to the inside of such containments to prevent leakage, but water infiltrating through cracks over a long time can swell the coating film until it breaks. To minimize such a risk, cracks in concrete are repaired by chemical grouting, etc., but from the aspect of shielding radioactive contaminants, such containments should preferably be maintenance-free.
 With this as a background, the authors conducted research on self-healing performance of heavyweight concrete containing an expansive additive, fly ash, and organic fibers based on water permeability testing and SEM analysis with the aim of self-repairing water leakage through cracking. As a result, the following were found within the range of this study: (1) self-healing led to early reduction in the water permeability, but the internal crack width scarcely decreased, with crack closure being observed only in the surface region; (2) the addition of an expansive additive led to self-healing at an early stage presumably due to chemical prestress and ettringite formation to fill fine cracking; and (3) the inclusion of fly ash and organic fibers appear to exert a self-healing effect slowly over a long time.

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 Currently, the construction industry produces significant amount of waste which generates more than 30% of the total industrial waste in many European countries. The large proportion of material waste generated in relation to materials consumed shows how waste has been unsustainably treated today. In general, this poor performance is due to dynamic and diverse characteristics of construction processes that cause inefficiency of resource use. Improvement in this area has been sought through various ways. In this respect, the use of 4D-CAD for efficient resource management and control is an area with great potential that has not been explored extensively. Current applications have shown positive results. For instance, the optimal install timings of building elements in construction can be suggested by connecting the construction process with digital objects to automate project visualization by means of animation. Thus, the potential for identifying inefficient planning solutions increases and improvement can be suggested. In addition, project progress can be monitored and managed through the whole construction process by comparing planning with as-build,
 In this study, 4D-CAD was adopted for demolition project planning. In this respect, process simulation was used as an additional support to decision-making that is often reliant on experience. For that, the volume of generated waste and the optimal timing of resource movement were estimated quantitatively with 4D-CAD. Blender, a free 4D-CAD software, was used to develop an impact simulation tool for demolition projects. Physics and game engines were used to automatically simulate demolition in accordance with physics laws. In addition, Python programming was used in the development of a Graphical User Interphase (GUI). Simulation results for the time-lapsed impact change from two variables; i) machine use and ii) waste generation. Animation recorded in simulation is also useful for better understanding of users as a visual aid.
 The testing of the tool involved the simulated demolition of a five-story building model created through BIM. Variables assessed included machine productivity for different demolition strategies and time-lapse change of waste generated. Time-lapse results of machinery productivity reveal the (in)efficiencies of different demolition processes. Waste generation data is classified by original (material) types and location; Waste distribution and purity levels are displayed on a demolition site map that forms the basis of a multi-factor waste recovery plan (e.g. machine transportation routes, collection order and timing). This process supports the definition of waste collection methods with increase purity levels and waste recovery rates. Limitations of the research includes the use of a simplified demolition method (e.g. single demolition machine and free-fall collapse).
 In summary, the aim of this research is to enhance the recycling levels of demolition waste within construction. For that purpose, a simulation tool was developed to estimate and qualify waste from building demolition using BIM enabled 4D-CAD combined with physics and game engines. The studied variables were machinery impact and waste output within alternative demolition processes. In addition, Waste Distribution Maps (WDM) are generated to support decision-making. This research represents a significant advancement in applied computing for building demolition waste recycling and notably improves the quality of information available in the definition of building demolition strategies. Further steps of the research include to increase the level of precision of the impact analysis, waste distribution and waste purity to levels that support after demolition waste treatment decision-making.

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 Strong ground motion which exceeds 1G was observed at KiK-net Mashiki (KMMH16) site in Mashiki Town, Kumamoto Prefecture, during the 2016 Kumamoto Earthquake. Since such large amplitude ground motion was observed, we discussed effects of soil-structure interaction on damage of a building located near the observation point. For large input ground motion, the interaction phenomenon becomes more complicated because of nonlinearity of soil deposit, soil near foundations, and structures.
 In this paper, our objective is to explain soil-structure interaction of Mashiki Town Office, whose damages of superstructure and piles have been reported. Since strong motion records were obtained at KMMH16 site and first floor of the town office building, we got rare data to evaluate the nonlinear soil-structure interaction of buildings supported by piles during large earthquakes.

 In order to achieve this objective, numerical analyses were conducted. At the beginning, nonlinearity of soil deposit of KMMH16 site was discussed based on one-dimensional nonlinear dynamic analysis. Secondly, the effect of gap between piles and clay soil on horizontal soil resistance of piles was discussed based on horizontal loading analysis for pile group which supports footing of the town office. Finally, using soil-pile-building system model of Mashiki Town Office, the effect of the gap on response at first floor and damage of piles was discussed.

 Results obtained from this study are summarized as follow:
 1) In the analysis at KMMH16 site, we assumed to decrease shear wave velocity in order to consider nonlinearity of deep soil for large input ground motions. As a result, calculated ground motion at the surface was good agreement with observed one.
 2) We calculated ground motions at Mashiki Town Office (MTO) site in order to obtain input ground motions for the interaction analysis. At this site, seismic motion amplification at soft volcanic clay layer was larger than that of KMMH16 site. While calculated shear strain of KMMH16 site ground was less than 1%, that of MTO site ground exceeded 2%.
 3) For cyclic loading on piles in the clay layer, the hysteresis of subgrade reaction-displacement curve had slip behavior because of the gap between piles and soil.
 4) In the analysis of the pile-building system of Mashiki Town Office, calculated acceleration response of the first floor was good agreement with observed one. From the result of the analysis considering slip behavior, it is suggested that the gap between piles and soil and continuous strong motions influenced response at the first floor and damage of piles because of decrease of horizontal soil resistance.

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 1. Many authors have been occupied with the development of elements for rectangular cylindrical shells. Sabir⁴⁾ proposed a new procedure using strain compatibility equations to make displacement fields of cylindrical shells. His element enables get considerably precise solutions of both static and dynamic problems of cylindrical shells. Here we adopt the strain stress function^10,11) of a cylindrical shell to get the displacement fields of the shell. The strain stress function is a single partial differential equation reduced the three equilibrium equations for the shell. Applying algebraic terms to the function enables us to get not only displacement vectors of the shell that satisfy the strain compatibility equations but also rigid motions and large displacement modes with small strains. An approach using the function is employed to develop new rectangular cylindrical shell elements that apply to the analyses of frequencies and a typical benchmark example of cylindrical shells.

 2. Basic Equations of Cylindrical Shell and the Strain Stress Equation
 Three homogeneous equations of equilibrium is expressed by Eq.(3), of which coefficients are constant values with the coordinate parameter ξ and η. The strain stress equation of the shell is expressed by Eq.(5). Applying algebraic terms on Pascal’s triangle to Eq.(5) let obtain displacement vectors , where e2 = 0. For example, applying G = ξⁿη^m to Eq.(5) yield a displacement vector u_nm. When introducing the vectors in Eqs.(A9), we get expressions where rigid motions are defined by power series of displacement vectors u_nm.

 3. Construction of Rectangular Element of the Cylindrical Shell
 3.1 Small Strain and Large Displacement Vectors
 Four rigid motions expressed by power series of displacement vectors unm, make no strains but some curvature and torsion, which are displacement vectors for large deformations with small strain energy.
 3.2 In-plane Displacement Vectors, 3.4 Approximate Expressions of Rigid Body Motions
 Instead of strict rigid body motion vectors, we set vectors Eq.(19) that approximate them. The displacement vectors with underlines are adopted in precedent sections 3.1, and 3.2. Eventually, this approximation gives only slight different results compared to the strict rigid motion.
 4. Numerical Analyses
 4.1, 4.2 Frequencies Analyses of Cylindrical Tank with Strict Rigid Motion and with Approximate Rigid Motion
 4.3 A Typical Pinched Cylinder, 4.4 Shape Functions derived by Basing upon the Approximate Rigid Motion

 5. Conclusion
 1. We utilize displacement mode vectors of the cylindrical shell element in which applying algebraic terms of two-dimensional coordinates to the strain stress function. The method is the first attempt to the knowledge of the authors.
 2. The rigid body motion of the element was expressed with a series of the displacement mode vectors.
 3. Some examples of cylindrical shell tank and pinched cylinder were analyzed. Obtained solutions are compared with the solutions obtained from the representative solution method of the past.
 4. Displacement vectors of u_Re5 and u_Im5 were introduced to the second order terms of the in-plane displacements. The main reason for realizing high-precision analyses is that the second-order terms of in-plane displacement are improved.
 5. By adopting software for mathematical expression processing, it is possible to explicitly express the shape function of the method that adopts approximate rigid body motions. This shape function for the cylindrical shell elements enables to apply not only to static linear analyses but also geometrical nonlinear problems and elastic-plastic analyses.

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 1. Introduction
 In applying vibration control techniques to buildings, if control systems are designed based on different dynamic parameters from real buildings, a decline of control effects is expected. Therefore, an accurate grasp of dynamic parameters of the buildings is important in order to control effectively. Current researches on an active vibration control based on estimated dynamic parameters usually focus on tower type buildings. On the other hand, few researches have been reported on shell and spatial structures that have complicate dynamic parameters. We attempt to apply the active vibration control based on the estimated dynamic parameters to a cylindrical lattice shell roof as an example of the shell and spatial structures. First, using control systems based on the dynamic parameters estimated by system identification, the control effects of the active vibration control are demonstrated. Moreover, by numerical analyses, effects of sensor arrangements for control on control stability are revealed, and then are demonstrated in horizontal uni-axial vibration tests.
 2. Outline of vibration tests
 A specimen of the vibration tests is a cylindrical lattice shell roof with its edge span of 1500 mm. Voice coil motors are used as actuators. Modal control and optimum control theory are used to calculate control force. Moreover, a design method for the active vibration control based on system identification is explained.
 3. Effects of sensor arrangements on control stability
 By the numerical analyses, effects of the sensor arrangements for control on the control stability are analyzed. First, a method to evaluate the control stability is explained. Next, the control stability of all sensor arrangement patterns of the number of the sensors for control is evaluated, and characteristics of the sensor arrangements that enable stable control are showed.
 4. Estimation of dynamic parameters specimen has by system identification
 The dynamic parameters the specimen has are estimated by system identification. Natural frequencies, damping ratios and eigen-mode vectors estimated by system identification are almost same as estimated values by other estimate methods and results of eigen analysis. But, factors against actuators are estimated less than the results of eigen analysis. This may be caused by friction.
 5. Analyses of control effects in vibration tests
 Applying the active vibration control based on the dynamic parameters obtained in chapter 4, results of the vibration tests are analyzed. Seismic responses are reduced by 40% by the active vibration control, without amplifying responses of all modes. Moreover, a demonstration of differences of the control effects between the sensor arrangements, that is, an experimental validation of the numerical analyses in chapter 3 is carried out.
 6. Conclusions
 As a conclusion, the following results are obtained.
 1) By the numerical analyses for all sensor arrangement patterns of the number of sensors for control, when measurement data include less a part of control modes compared to a part of modes except for control modes, it becomes easy to select the sensor arrangements which enable the stable control.
 2) The plural dynamic parameters the cylindrical lattice shell roofs have can be estimated accurately by system identification from the responses on the same position as the sensor arrangements for control. Moreover, using the control systems based on the results of system identification, the seismic responses was reduced in the vibration tests.
 3) When the sensors are arranged to the positions that enable the stable control, the seismic response of the cylindrical lattice shell roofs can be reduced by 40% by the active vibration control, without amplifying the responses of all modes.

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Spatial structures are used as evacuation facilities and aid stations when a large earthquake occurs. In order to ensure sufficient seismic performances. Therefore, there are studies on free vibration characteristics of existing structures and effects of roofing members on damping factors. However, the effects of differences of flexural rigidity of roofing members and coefficients of friction between roofing members and lattice members on free vibration characteristics have not been sufficiently investigated. From these backgrounds, these effects on free vibration characteristics and seismic response behavior of cylindrical lattice shell roofs under horizontal motions are investigated by shaking table tests.

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 Large-span steel moment frames are used as the main structure in many gymnasiums. Several studies pointed out that significant deflection in such moment frames was caused by inelastic seismic response for horizontal earthquake ground motion. This paper explains how horizontal excitation causes large accumulated deflection, and theoretically formulates the relations between vertical deflection and inelastic deformation. The moment frames made of H-shaped steel is considered herein, where shear yield of panel zones occur in advance to forming flexural yield hinges.
 Since gymnasiums are used as shelters in earthquake disaster, we need a method to evaluate the structural damage quantitatively, by inspecting and measuring the deformed gymnasium. By measuring the deflection after earthquake, we might be able to estimate the plastic deformation. In this paper, the possibility is discussed using FE dynamic response analysis.
 The mechanism how horizontal deformation causes accumulated deflection is summarized as follows. In elastic behavior, the moment distribution in the beam for horizontal load is antisymmetric. After forming two yield hinges at two ends of the beam, the moment distribution does not change and is also antisymmetric. In the both cases, the deflection does not increase. However, when only one yield hinge is formed at the leeward side, the deflection increases with the horizontal load due to the change of moment distribution until two hinges are formed. In this paper, bi-linear constitutive relation between the shear strain and moment acting on the panel zone is assumed and theoretical solution on the behavior is derived. The theoretical solution was verified by pushover FE analysis and good agreement was observed.
 By applying the derived theoretical formulas, ductility factor on the both panels can be estimated from the deflection. Dynamic response analysis was also performed to verify the estimation. This could be a useful method to estimate structural damage in the moment frame after earthquake.

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 The past inland crustal earthquakes, such as the 1rr5 Hyogo-ken Nambu earthquake, the 2007 Nigata-ken Chuetsu-oki earthquake and the 2016 Kumamoto earthquake, destroyed many wooden structures in Japan. It is desirable to conduct appropriate seismic reinforcement in order to prevent inland crustal earthquakes occurring often in recent years from pushing down wooden buildings.
 Authors have been doing research on seismic reinforcement for traditional town houses, machiya, in Kyoto¹⁾. The findings obtained from the research are as follows: machiya's joints are not strong enough to resist to horizontal member's pulling out in particular, and severe damage in a specific story caused by the unbalance of yield strength and stiffness in each story or plane structure lowers the deformability. In other words, for conducting rational seismic reinforcement, it is preferable that we can design with reinforcing elements which allow us to control elements' mechanical characteristics in accordance with features of structures.
 Wooden grid wall^2)-6) and ladder-type frame^7)-9) are suggested as reinforcing elements for wooden structures. In both of them, wood's embedment at joints resists seismic force. However, as well as the experiments in reference1), these reinforcing elements may be ineffective if their position or strength is improper.
 Therefore, authors propose a new reinforcing element, called Amida-shaped frame, composed of columns and horizontal members. Amida-shaped frame can be controlled its strength and deformability by changing the number and the size of columns and horizontal members. By using Amida-shaped frame which has such characteristic, we aim to establish seismic reinforcement method which is applicable to various structures.
 From the above, first, we conduct static loading tests of Amida-shaped frames for comprehending their mechanical characteristics. Then, we simulate the static loading tests with analysis models to confirm the mechanical characteristics which can't be identified at experiments. This paper is original in proposing that it is important to consider horizontal member's bending deformation, breakage, axial force and to say nothing of embedment when we design Amida-shaped frame.
 The major findings obtained from the research are summarized as follows:
 a) The maximum horizontal force of Amida-shaped frames rises in proportion to the total number of horizontal members. The particular damage is breakage of horizontal members at the columns' surface. When the horizontal member breaks, the horizontal force drops rapidly.
 b) When the height of horizontal members is bigger, the rotational angle when the horizontal member breaks and the maximum horizontal force are larger. The bigger the height of horizontal members is, the less the ratio of the maximum bending moment to the flexural capacity is.
 c) In case the height of horizontal members is small, we are capable of overstimulating the rigidity if we don't consider the bending deformation of horizontal members.
 d) If we don't consider the axial force of horizontal members appropriately which derives from embedment at joints of columns and horizontal members, it is difficult to evaluate the bending moment distribution of columns.

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 The seismic retrofitting of old constructions is important in earthquake-prone countries. There are areas in Tokyo, Japan with Densely Built-up Wooden House Areas. These regions face the serious task of building seismic resistance and/or fireproof properties in the buildings in the entire area. Thus, studies related to ensuring the soundness and stability of the city and its buildings, are necessary, not only for disaster prevention but also for urban planning and community revitalization.
 Early Showa period billboard architectures, named by Prof. T. Fujimori, constructed in downtown Tokyo after Great Kanto earthquake of 1923. They are a type of residential housing with an integrated store. They are wooden residences with a mortar wall or sheet copper, which combined billboard, located only at the front of the building. They may have two problems. The first problem centers on the assumption that the stiffness of the billboard wall is higher than that of the remaining wooden frames. Thus, the eccentricity of the entire building may be greater than that of a typical wooden structure because of maldistribution of the earthquake-resistant elements. Secondly, it is feared that there are fewer earthquake-resistant columns and walls on the ground floor behind the billboard wall because the ground floor is a store. It is very important to understand their seismic behavior, aiming to preserve the old townscape along old shopping streets and to utilize the billboard architectures.
 In this paper, we research on seismic behavior of the billboard architectures in Chuo-3, Ota City with Densely Built-up Wooden House Areas. First, we conducted an exhaustive survey of 809 buildings and roads, and microtremor measurements on the ground at 25 points in the area. Next, measuring the dimensions of the billboard architectures, standard analysis models were constructed. We conducted seismic response analysis to evaluate response characteristics. Lastly, eigenvalue analysis to evaluate their respective vibrational properties, such as the natural frequency and vibrational mode. After that, sensitivity analyses were conducted on the floor rigidity or materials of the walls.
 The major findings from this study are summarized as follows: (a) The buildings in the area divided into geographic sections were densely packed. There were early Showa period billboard buildings along the local traditional shopping street. Nearly 80% of all billboard buildings were located 1 m or less from the frontal road. (b) H/V spectrum on ground changed gradually from the west to the east. The peak of the natural frequencies can be specifically determined in the west side, but the peak value gradually disappears toward the east. (c) The first story exhibited the maximum story deformation angle along the frontal plane of the billboard. Additionally, the story deformation angle of the first story significantly differed from that of the second story. This is because there are fewer earthquake-resistant elements built into the first story and because the second story has a thick billboard wall. The amplitude differed between wooden structures and the billboard. This is because the eccentricity of the entire building may be larger than that of the typical wooden structure. (d) Supposing repair work, sensitivity analyses were conducted on the structural model to evaluate the vibrational properties of billboard architecture. Within the limits of our research, balance is good when stiffness is designed in close value between floor above and below.

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 The calculation method for pull-out performance on lagscrewbolt (LSB) joint embedded in parallel to the grain of glued laminated timber is proposed in this paper. The shear stress distribution of the boundary zone between LSB and timber along LSB and material properties are separately considered in the formulae.
 These formulae are derived by using the axial stress distribution along LSB which is calculated from the shear stress distribution function of the boundary zone along the LSB proposed in the past studies. These formulae are practical because they do not require any experimental efforts but only uses the given values such as specified design strength of materials that is defined in the notifications of MLIT.
 The mechanisms of the yielding strength and the maximum strength of LSB joints are theoretically elucidated. The formulae to predict the yielding strength and the maximum strength which are derived based on these mechanisms are verified by numerical analyses.
 It was found that the ductility of the boundary zone is strongly related to the ratio of the yielding strength to the maximum strength. When the ductility of the boundary zone is poor, the yielding strength is equal to the maximum strength. When the ductility is sufficient, the maximum strength is reached when the boundary zone in all area yields. These tendencies were confirmed by numerical analysis.
 In the past studies, the pull-out elastic stiffness obtained from experiments disagreed with the calculation results because of different definitions of the pull-out displacement of LSB joint between the experiment and calculation.
 In this paper, the relative displacement between the position of the timber at the tip of LSB and the position of the root of LSB is defined as the pull-out displacement of the LSB joints. According to this definition, it is confirmed by numerical analyses that the pull-out elastic deformation of the LSB joint is the total value of the elongation along LSB and the shear deformation of the boundary zone at the position of the tip of LSB.
 The formulae derived here were verified by the pull-out test which was conducted under different types of LSB, wood species and embedment lengths.

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 The moment carrying capacity of beam-to-column joint (Sashigamoi) on a large size column has sufficient strength property in structural designing the traditional timber buildings. The load carrying capacity of traditional timber joints such as Sashigamoi joint is based on timber-to-timber interlocking resistance. In general their complicated composition of members makes it difficult to estimate the structural performance. This paper reports the evaluation of rotational performance of one of the traditional timber joint with spline member connected by inclined shear-key (Shachi-sen).
 At first we conducted a strength test of the joint with varying dimensional and loading conditions. From the moment-angle relationship of the test result and observation of failure mode, a different resistance mechanisms of symmetric and asymmetric bending situation was suggested. The one mechanism is horizontal resistance depending on tensile force of shear-key joint and bearing force on beam against column which is so called tensile bolt effect. The other working mechanism is bracket effect induced by vertical couple of force resistance applied at the tip of the spline and the tenon.
 Then formulas based on mechanical models which are able to estimate not only stiffness and yield strength but also a large deformation behavior until final failure were proposed based on the above mentioned mechanism and experimental phenomena by considering the equilibrium of force and compatibility condition of the displacement. The working mechanism of tensile bolt effect was modeled in the tri-linear curve on which first yield is decided by compression yield and then followed by ultimate state caused by tensile strength of spline key joint, while the mechanism of bracket effect was modeled in bi-linear relationship.
 Finally an additional series of experiment was carried out to verify the formula. The moment-rotation angle relationship of joints estimated by the proposed formula with inputting size parameter, material constant and tensile strength parameter of unit Shachi-sen joint which was obtained by the mechanical model proposed in the pre-reported paper. The results were in good agreement with the test results, which confirmed the certainty of the model.

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 Seismic retrofitting has recently become crucial for buildings designed under old seismic codes. Post-installed anchors or disk-type shear keys are generally applied to joints of seismic retrofitting structures, which are further anchored to the existing members by applying epoxy adhesives. Although epoxy adhesives have been studied extensively, few studies exist on cement-based adhesives. Therefore, we conducted a pull-out test, a shear loading test, and a two-dimensional (2D) FEM analysis to investigate the adaptability of cement-based adhesives to disk-type shear keys.
 In Chapter 2, the test plans for the pull-out and shear loading tests are detailed. Nine specimens were prepared for each test. The parameters of the pull-out test include the concrete compressive strength σ_B (10-30 N/mm²), adhesive type (epoxy or cement-based adhesive), and anchor bolt type (fully threaded bolt or round steel bar). The parameters of the shear loading test are σ_B and adhesive type.
 In Chapter 3, the FEM analysis is outlined. In this analysis, the concrete and the steel are considered as a plane stress element, the stud bolts as a beam element, and reinforced bars as a truss element. A concrete thickness of 135 mm (=1.5R_d, where R_d is the diameter of the steel disk) is considered as the damage area of the disk-type shear key. The analytical parameters are the concrete compressive strength σ_B and the adhesive type. In adhesive type, the case of “unbonded” is also added as a parameter.
 Chapter 4 describes the test results. According to the results of the pull-out test, use of the cement-based adhesive with a fully threaded bar resulted in the same maximum bond stress as with epoxy adhesives. However, the maximum bond strength was 0.2-0.3 times the bond strength in case of a round steel bar. The shear loading test results indicated that the shear forces of the cement-based adhesive were slightly smaller than those when the epoxy adhesive was used.
 Chapter 5 describes the analytical results. First, the bond-slip behavior of adhesives was modeled from the results of the pull-out test. The analytical outcomes of the nine cases were calculated. The Q–δ curves obtained from the analysis and the experiment were similar. Moreover, the shear forces in the unbonded case were smaller than those in case of epoxy and cement-based adhesives because the bearing resistance area was smaller because of the pulling out of the anchor bolt.
 Chapter 6 presents the conclusions of the study, which are summarized as follows:
 1) The results of the pull-out test using an epoxy adhesive and a round steel bar show a safety ratio exceeding 1.0, but with a higher standard deviation.
 2) The pull-out test results indicate that the combination of a cement-based adhesive and a fully threaded bar resulted in the maximum bond stress same as that in case the when an epoxy adhesive was used. However, a round steel bar exhibited the maximum bond strength that was 0.2-0.3 times the bond strength.
 3) The shear loading test results show that the maximum shear force of the specimens using cement-based adhesives was approximately 10% smaller than that of the specimens using epoxy adhesives. These maximum shear forces were, however, higher than the calculated shear strength in most specimens.
 4) The shear behavior could be reproduced by the 2D FEM analysis by setting the concrete element thickness to 1.5 R_d.
 5) The bond strength and the vertical displacement of the anchor bolt obtained by the analysis were smaller and larger, respectively, compared with the experimental results.
 6) From these investigations, it was concluded that cement-based adhesives can be applied to disk type shear keys.

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 Damage to non-structural walls has been considered as one of problematic damages to reinforced concrete members since 1990's. Damage to non-structural walls is not critical to save buildings from collapse but its impact on the building function is nearly as critical as damage to structural members. The cost to repair, to compensate downtime, and to recover credibility differs dramatically for buildings with and without non-structural wall damage. This paper demonstrates superb quick recovery performance of unbonded post-tensioned precast rocking wall from both experimental and numerical view points in order to alleviate the impact of non-structural wall damage and to take advantage of its self-centering capability.

 Firstly, quick recovery performance of two unbonded post-tensioned precast concrete (UPT-PC) walls was reviewed. Two UPT-PC walls, tested in Tokyo Institute of Technology in 2015, were 1800mm tall with cross sections of 200 x 1100mm (NSW6A) and 200 x 450mm (NSW7A). The test was carried out under cyclic static lateral loading with constant axial load. Both specimens showed excellent quick recovery performance with negligible residual drift and cracks. The damage level of specimens was evaluated using four limit states listed in the 2015 AIJ draft for structural design and construction of prestressed concrete buildings on performance evaluation concept guidelines. The determining factor for each limit state was mostly governed by compressive damage of concrete. It was found that the compressive damage of concrete occurred when the average compressive strain of concrete reached much higher than that based on the existing theories; for example, strain was 0.4% for compressive crack, 0.78% for cover spalling, and 1.13% for crushing of cover concrete for NSW7A.

 Secondly, the behavior of walls was numerically simulated with a multi-spring model. Assuming the damage length in compression is half of the wall length, the multi-spring model accurately simulated hysteresis loops of load-drift relation and tendon force － drift relation for both specimens, leading to relatively precise simulation of residual drift and equivalent damping ratio. The numerical model was able to evaluate the timing and determining factors of each limit state. As a result, detailed damage levels of analyzed walls were successfully classified to have a good agreement with experimental results.

 The results of numerical analysis, in addition to the experimental results, demonstrated the superb quick recovery performance of the unbonded post-tensioned precast rocking wall.

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 1. Introduction
 It is important for structural design practice to comprehend plastic deformation demand of members in steel frames under large earthquakes. The authors proposed a method of prediction of maximum story drift angle of single-story steel frames with braces, which modifies a method supposed by Ref. 17, however it is complex and difficult to use. Then, in this paper we propose a simple and valuable method to predict maximum story drift angle and dissipated energy demand of single-story steel frames with braces, based on the energy equilibrium.
 2. Examination of the analysis model of the braces
 In order to verify the analysis model which can agree well with real behavior of braces, three kinds of analysis models are picked up, and analysis results compare with past test results, whose cross section shape are rectangle, H-shape, circular tube. One of the analysis models is generalized plastic hinge model (Ref. 23), the second is a single spring model by Kato & Akiyama (Ref. 24), and the other is a single spring model by Shibata & Wakabayashi (Ref. 25). Analysis results of Kato & Akiyama’s model don’t agree well with test results of rectangle section braces with varying slenderness ratio. On the other hand, the analysis results both generalized plastic hinge model and Shibata & Wakabayashi’s model are almost agree with test results. It is notable that only slenderness ratio affects on the hysteresis characteristics of braces regardless of cross sectional shape if local buckling doesn't occur.
 3. Modeling idealized hysteresis characteristics of braces
 An idealized hysteresis characteristics of brace is proposed based on result of static incremental analysis by using the generalized plastic hinge model. It is the most progressive point of this hysteresis characteristics from past researches that the strength of brace during slip behavior is modified based on the averaged response under target input level.
 4. Prediction method of plastic deformation demand of single-story steel frame with braces
 A method to predict maximum story drift angle and dissipated energy demand of single-story steel frames with braces is proposed, based on the energy equilibrium. The method is categorized by yielding situation of main frames, and considers with ratio of input energy in half cycle to total input energy (r_cycle). Derived equations for prediction are continuous explicit functions at the point of the main frames just yielding.
 5. Verification by time history response analysis
 Time history response analyses are conducted to confirm validity of the proposed prediction method. Braces are modeled by elastic bars with generalized plastic hing models, and are linked to the mass point. Main frame is modeled by shear spring and linked to the mass point. The parameters of steel frame with braces are slenderness ratio of braces, horizontal resistance sharing ratio of braces, structural characteristics factor, ratio of the yield story drift angle of the brace to the frame. As maximum story drift angle, dissipated energy of braces and frames are compared between analysis and prediction, it is clarified that prediction method is valid and useful for all analysis cases.
 6. Conclusion
 The main findings are summarized as follows.
 1) The prediction in case of r_cycle=0.4 agrees well with the upper limit of dissipated energy of frame and maximum story drift angle of single-story steel frames with braces.
 2) The prediction in case of r_cycle=0.1 almostly agree with the upper limit of dissipated energy of braces of single-story steel frames with braces.
 3) Strength degradation of braces caused by overall buckling does not depend on the cross-sectional shape and affects on only slenderness ratio.

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 The reuse system is one of methods to reduce environmental burden in the structural field. In the pre-demolition survey, information such as building design documents and steel material standard certificates are collected to confirm. After demolition of target buildings, based on the results obtained by destructive-test or non-destructive test, the degree of damage for reuse is evaluated. Design method of building steel structures for reuse consists of three types which are elastic design method, elasto-plastic design method, and design method considering damages of structural members, and they are used in accordance with structural performances.
 In this paper, the authors propose design method of building steel structures considering damage of structural members for reuse introducing reduction ratio. Seismic performance of braces in the longitudinal direction introducing reduction ratio of structural members is estimated. Between a dynamic ductility index of structure and reduction ratio of structural members are discussed by seismic response analysis. Seismic performances such as the ultimate displacement, the yield base shear force coefficient and initial natural period are investigated.
 The following findings are obtained from the results of our analyses.
 1) The concept of seismic performance evaluation introducing the reduction ratio of structural members by strength and rigidity for reuse is shown.
 2) Dynamic Ductility Index of each model with reduction ratio is proportional to the strength reduction ratio β_s. Dynamic Ductility Index is approximately evaluated by index when the critical displacement decreases by the rigidity reduction ratio β_D.
 3) Dynamic Ductility Index of each model with reduction ratio increases in accordance with increasing average ductile coefficient. On the other hand, Dynamic Ductility Index of each model does not change in accordance with increasing a yield base shear coefficient. Dynamic Ductility Index is mainly affected by initial natural periods.
 4) Required the yield base shear coefficient can be shown by Contour of Dynamic Seismic Performance Index using the reduction ratio of structural members.

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H-shaped steel beams in moment frames are restricted in axial deformation by columns, other beams and floor slab. Although it is considered that deteriorating behavior of beam is affected by such axial deformation restriction, there are previous studies about deteriorating behavior of beams after occurring only lateral-torsional buckling. In this paper, cyclic loading test and finite element analysis (FEA) were carried out to reveal effect of axial deformation restriction on deteriorating behavior of beams when local buckling or fracture occurs. Based on FEA results, a method to verify criterion where axial deformation restriction should be considered is proposed.

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