The apparatus with electromagnetic waves of frequency 2.45GHz, such as microwave ovens, are mass-produced, therefore producing a magnetron for the electromagnetic wave of frequency 2.45GHz has become inexpensive. We study heating mortar blocks using magnetron of frequency 2.45GHz for melting snow to convert an electromagnetic wave into heat. The heating mortar block can melt snow in a shorter time than systems with electric heating wires for melting snow. But the heating mortar blocks need electromagnetic shielding material to prevent electromagnetic waves from leaking out of the blocks. Steel fibers as the electromagnetic shielding material is adopted to improve construction efficiency. The quantity to shield an electromagnetic wave are more than 20dB in frequency 2.45GHz.
 The characteristic of the electromagnetic shielding materials is confirmed by the shield box device. The shield box device has double rigid horn antennas. The measurement is carried out by S parameter. The quantity of electromagnetic shielding is measured by installing the sample which arranged steel fibers between the horn antennas. The measurement is performed two times: when the steel fibers are arranged vertically in the direction of electric field and when it is arranged parallel.
 The following things were discovered. First, when the steel fibers are arranged vertically in the direction of electric field, the steel fibers can shield almost none of the electromagnetic wave energy. When the steel fibers are arranged parallel to the direction of electric field, the arranged steel fibers can shield the electromagnetic wave energy. But there is the frequency where a lot of the electromagnetic wave energy is shielded. We call the frequency where a lot of electromagnetic wave energy is shielded "peak frequency".
 Second, the influence on characteristics of the electromagnetic shielding by the length of the steel fibers were checked. The longer the steel fiber becomes, the lower the peak frequency becomes.
 Third, the influence on characteristics of the electromagnetic shielding by the distance of the arranged steel fibers were checked. The bigger vertical distance in the direction of electric field grows, the lower the peak frequency becomes. If the distance of the parallel direction in the direction of electric field becomes more than 40mm, the performance of the electromagnetic shielding becomes low. If the length of the steel fiber and a radius of the steel fiber are known, the inductance of the sample can be calculated. The capacitance of the sample can be estimated by the measurement and the inductance of the sample. The relationship between the vertical distance to the direction of electric field and the peak frequency can be calculated by the inductance and the capacitance of the sample.
 Fourth, the characteristics of the electromagnetic shielding when the steel fibers were arranged in mortar were checked. When the steel fibers are arranged in mortar, capacitance increases under the influence of mortar. Therefore, the peak frequency becomes low.
 Fifth, the arranged steel fiber which was made by cutting wire netting to improve efficiency of the construction, was made. The cut wire netting has better electromagnetic shielding performance than normal wire netting.
 Finally, the heating mortar blocks using mortar which includes cut wire netting was made. This heating mortar blocks shielded the electromagnetic wave energy with more than target quantity in frequency 2.45GHz.

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 It is important to develop an information traceability system on the process of concrete production. One method is to record an identification number or the information about the concrete production with wireless IC tag, and to put it into the concrete that has not yet hardened. This method has a characteristic to keep the information inside the concrete itself. On the other hand, this method requires communication performance between IC tag inside the reinforced concrete member and the IC reader/writer outside the concrete member. This paper investigates the communication performance of IC tag embedded in the actual reinforced concrete floor slab.
 Firstly, we have developed a new communication performance index to evaluate the possibility of wireless communication of the IC tags embedded inside concrete slabs. The index has been calculated through the experiments on various molding conditions such as relative locations of reader/writer and reinforcing bars (6 standards), relative direction of IC tags against reader/writer (24 standards), and various depth from concrete surface.
 Secondary, the index is measured and calculated in actual slab concreting works, in order to investigate the applicability of the index. The calculated index values were larger than the measured values, although only one construction site is available for this comparison.
 Lastly, the least number of IC tags to make a product traceable has been investigated through the above experimental results and analysis.

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 Surface qualities of concrete ground works influence performance of floors mightily. The flatness is one of the qualities which are required to concrete ground works. Flatness of concrete ground works reflects the flatness of floor finishing. In particular, this tendency is prominently in coating floors and sheeting floors which are carried out by putting finishing materials on the concrete ground works directly.
 The purpose of this study is presentation of an evaluation method about the flatness of concrete ground works from a viewpoint of feeling by foot touch while stepping. In addition, we present construction management index for establishing target values of the flatness depending on requirement qualities while constructing concrete ground works.
 Method of this study is following.
 1) Some sample floors simulating real concrete ground works are constructed to make real flatness.
 2) Sensory tests about feeling by foot touch are carried out using the samples. Psychological scales about the flatness are constructed base on results of the tests.
 3) Flatness of the samples is measured.
 4) Performance value corresponding to the scales is established by considering relationships between the results of 2) and 3). And the evaluation method based on the performance value was presented.
 5) The performance value is calculated from many results of flatness of concrete ground works which the authors have.
 From these results, management value is also calculated which is used to manage the flatness in construction sites.
 Finally, we present construction management index by considering relationships between the performance value and the management value.
 Conclusion of this study by above method is following.
 1) Asperity on front-back direction and slope on crosswise direction in the area of touching sole are quite influence evaluation of the flatness. The degrees of influence of asperity and slope are variable by actions, hardness of sole and deformation properties of finishing materials.
 2) The performance value corresponding to the psychological scales was established from the asperity and slope measured by using straight edge. In addition, the method of collating the performance value to the relationship diagrams was presented as the evaluation method about the flatness.
 3) The performance value established by this study and the management value established by Japan Research Conference of Floor Construction Technology were calculated from much data of concrete ground works. Finally, the construction management index was presented by replacing the performance value to the management value based on the relationships between each other.

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 In the Great East Japan Earthquake, a large number of buildings collapsed and the strength of ceiling boards using plaster finishing was occurred as serious problems as a possible problem. That is why, since the Great East Japan Earthquake, the owners of old buildings are concerned about the deterioration of the building components. Therefore the number of owners seeking to strengthen their building's components have been increasing day by day. Moreover, in addition to preserving these historical buildings, it is also necessary to secure the safety from the standpoint of cultural and historical values. Therefore, we focused on these wooden lath and plaster ceiling that's used as a target of evaluation for saving the historical building. In this study, an experimental study of inspection of an existing wooden lath and plaster ceilings, we evaluate the strength and other properties of plaster, and finally conduct the objectives to prolong the duration of life with safety conditions.
 Plaster materials have been frequently used in old building's ceilings and walls. In general, the role of plaster ceilings are to transfer stress buffering between the lath and plaster. Therefore, it is important for the lath and plaster to be strongly adhered. This portion has been called Plaster Key in general and its role is to evaluate the mechanical properties of the plaster ceiling and wall. In Japan, this type of ceiling using plaster and mortar has been used from the early 1900s, and over a century has passed since the lath and plaster ceilings were developed, and at the same time the plaster has been frequently damaged in earthquakes.
 Stress transmission of lath and plaster are into the four patterns. The shear resistance is a stress. Shear is a stress that caught the lath. The tensile resistance is a stress that support the load of plaster. The bending resistance is a stress against the deformation of the plaster. The adhesive resistance is the stress of the adhesive surface of the plaster and lath. The lath and plaster ceiling specimens could be evaluated to measure the strength conditions of the ceiling member. This specimen was made in suspending conditions of same environment of the ceiling. The tensile testing instrument was attached to the surface of the finishing plaster after curing. The tensile strength test was enforced to pull plaster against the lath and record the peeling resistance in maximum load, the plaster deformation, and destruction pattern of plaster key.
 The results of strength examination of the plaster containing fiber, the maximum stress of the plaster was increased, and the fracture energy was increased. The case of including small fibers was effective at increasing the shear stress, stress in a similar function as reinforced concrete rebar. Then, as for the plaster containing sand, the maximum stress was not increased. As for the flexural strength, the plaster including the maximum amount of fiber was increased by increasing fiber contents, and the fracture energy of the sand was reduced.
 The results of strength examination by the lathing plaster specimen, the breaking load was correlated with the width of the wooden lath clearance. As the length between wooden lath and the plaster is closer, the length between the lath and plaster, the plaster key would expect strong mechanical interlocking conditions. However, if the amount of sand is too large, the positive effectiveness was eliminated, the strength would be decreased.

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 Experiments using a reservoir discharge type flume with an orifice are conducted to investigate the dynamic characteristics of finite width wall structures attached to a flexible cantilever support subjected to surge forces. The surge acts as a step-like force with finite rise time in which the response is governed by the structure's vibrational properties. A structure vibrating under a single mode can be modeled as a single-degree-of-freedom(SDOF) system. When the structure is subjected to a surge, parts of its surface are submerged in water, giving rise to added intertial and hydrodynamic damping forces, which can be expressed as added masses and hydrodynamic damping coefficients. The focus of this research is to investigate and model the added mass and hydrodynamic damping coefficient for wall like structures subjected to surge forces. From potential theory, the added mass depends on the water density, inundation height, width of the structure, and their ratio. Assuming that the hydrodynamic damping has a form similar to aerodynamic damping, the hydrodynamic damping coefficient depends on the water density, water velocity, inundation height, width of the structure, and the ratio between inundation height and width of the structure.
 In order to investigate the added mass and hydrodynamic damping coefficient, finite width walls mounted on a flexible support are selected as the structural system. Three different materials and two different widths are selected as parameters for the wall. The first fundamental mode is translational in the direction of the flume. Two types of experiments are conducted. One in which the added mass and hydrodynamic damping coefficient is extracted from the system submerged in various inundation depths of still water, and the other in which they are extracted from the system subjected to surges resulting from 4 different initial reservoir heights. The former is conducted to obtain the ideal properties of the system when both sides of the plate are submerged in water as opposed to the latter which is to obtain actual properties of the system when only a single side is submerged. The time history of the measured response shear force of the structural system is decomposed into the quasi-static average force corresponding to the applied surge force and the oscillating dynamic force corresponding to the vibration of the structure, from which the added mass and hydrodynamic damping coefficient is obtained.
 From the stillwater experiments, a monotonic increase in added mass with respect to an increase in inundation depth was observed. By incorporating the mode of vibration and reduction of added mass due to the free water surface, the added mass can be modeled using the wall width, inundation height, and aspect ratio. From the surge experiments, a positive correlation between the added mass and inundation height is also observed, from which an added mass model similar to that for the stillwater case can be developed. The relationship between the total damping coefficient (material damping coeff. + hydrodynamic damping coeff.) and inundation depth obtained is dispersed but has a trend similar to the hydrodynamic damping model based on aerodynamic damping.
 Time history analysis is conducted, using the surge force, inundation height, and velocity time histories obtained from the experiments as input into the SDOF system with proposed added mass and hydrodynamic damping models. By using the proposed model, the decrease in fundamental frequency as well as the increase in damping observed in the experiments is adequately modeled. Though the damping is slightly overestimated for surges with smaller initial reservoir heights.

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 The purpose of this study is to understand the effects of the external pressures and internal pressures on the wind loads to use in wind-resistant design for the cladding of high-rise buildings. In order to measure the external pressures acting on the assumed high-rise building, a wind tunnel experiment using the reduced scale model of 1/250 was conducted. This assumed building is a high-rise building with an eaves-height of 45m having a rectangular plane width of 40m and a depth of 25m. The wind tunnel facility used in the experiment was the closed-circuit type boundary-layer wind tunnel having a testing section length of 20m, height of 2.5m and width of 3.6m. The characteristics of the boundary-layer flow used in the experiment were to match the nominal flow of the flat terrain of neutral stability conditions. The external pressures on the scale model of the assumed high-rise building were measured using the multi channel simultaneous measuring system (MCSMS). Details of the wind tunnel experiment are discussed in Chapter 2. The numerical simulation used both a leakage flow model and the external pressure was conducted to estimate the internal pressures in the assumed building induced by the wind. The leakage flow model has been constructed by applying Poiseuille's law. Details of the numerical simulation are discussed in Chapter 3. The net pressure was evaluated by subtracting the internal pressure from the external pressure. In Chapter 4 the properties of the net pressure coefficient, the external pressure coefficient, the internal pressure coefficient, and the power spectrum density distribution and probability density distribution are discussed. In Chapter 5 the correlation properties of between the external pressures and the internal pressures are discussed. In Chapter 6 the properties of the peak values (maximum and minimum) of the essential net pressure coefficients to the wind-resistant design of the cladding are discussed. Both of the largest peak net pressure coefficients and the largest peak external pressure coefficients (worst value in any wind direction) are compared with the recommendations values (2015) of AIJ in this Chapter. In Chapter 7 the method of approximating the peak net pressure using the mean internal pressure and the peak external pressure is discussed. Furthermore, in this Chapter the method approximating the peak net pressure using the peak external pressure and the peak internal pressure is also discussed.
 From the above results, the following findings were obtained.
 1) The effects on the net pressure fluctuations of the external pressure fluctuations are more dominant than the internal pressure fluctuations.
 2) The effects on the net pressures of the partitions are remarkable in case of a low airtight.
 3) The probability distribution of the net pressure can be approximated by a Gamma distribution or Gauss distribution based on the skewness, the same as external and internal pressure.
 4) The correlation coefficients between the external pressures and internal pressures on the cladding are almost positive values.
 5) The largest (worst) maximum net pressure coefficient for any wind direction on the cladding of the assumed high-rise building of a high airtight almost agreed with the recommendation values (2015) of AIJ.
 6) The tightness effects on the largest minimum net pressure coefficient are small.
 7) In case of the building with a high airtight, the peak net pressure on the cladding can be approximated using the mean internal pressure and the peak external pressure.
 8) The peak net pressure on the cladding obtained from the peak value of the external pressure and internal pressure is evaluated on the safety side, in case of independent.

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 We have reported an active seismic response control system by making use of an energy conversion in damping devices. This system changes the vibrational energy of the structure by large earthquake with a damper, and accumulates it. Then, it reuses this energy, and drives an actuator as vibration control device. This study suggests an active absolute seismic response control by utilizing energy conversions in dampers, and reports the analysis of proposed system characteristics for the base isolation structures.
 (1)From the seismically response analysis results, we can reduce the maximum acceleration response within 3-25cm/s2 for the proposed system, showing the drastic response reduction effect compared with the common base isolation system.
 (2)An added energy (E) becomes large and an absorbed E becomes small in the energy of the actuators in accordance with the increase of the damping factor for passive dampers, depending on earthquake characteristics. The amount of energies becomes small in accordance with the period of base isolation structures.
 (3)The input and output of energy balance (Passive E exceeds added E.) is ineffective for earthquakes with large displacements compared with velocities. In addition, the energy conversion of passive dampers is created by adding powers of actuators.
 (4)Through the feature of the active absolute seismic response control, we show that the various energy can be evaluated using the structural characteristics of base isolations and earthquake’s characteristics without seismic response analyses.
 (5)For the setting conditions, we assume the input and output energy balance is formed by decreasing the displacement gain Gd, and the acceleration response of the base isolation story can be reduced to 1/5 of common base isolation structures. This setting condition tends to be formed in accordance with the increase of the damping factor and the period of base isolation structures.
 (6)Proposed system, i.e. the absolute response control forming the input and output of energy balance, can reduce the control force and the acceleration response of the base isolation story compared to the absolute velocity feedback control.
 We have presented the realization possibility of the seismic response control system showing the drastic response reduction effect without the energy supply, being equivalent to the active absolute seismic response control, through the characteristics analyses of the active absolute seismic response control by utilizing energy conversions in dampers.

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 Since seismic isolation systems have high seismic performance, the number of the general commercial construction of base-isolated buildings has been increasing recently. For Nuclear Power Plants (NPPs), on the other hand, even though there have been a lot of researches to apply seismic isolation systems, the base-isolated plant has not been built in Japan. Recent seismic regulation requires to evaluate seismic safety including ultimate behavior for NPPs generally, therefore, ultimate behavior of NPPs adopted the seismic isolation system must be also considered in the seismic residual risks: e.g., the hardening or the breaking of seismic isolators in the horizontal deformation.
 In this research, the energy balance-based seismic response prediction methods and its design method will be treated as the seismic safety evaluation in the large horizontal deflection region. In the paper, especially, a scheme of a mechanical energy balance evaluation is proposed for investigating ultimate behavior in the large deflection region, where one can estimate mechanical energy transition from experimental records of relations restoring force and shear deflection on a isolation-layer of a base-isolated system or on a sole isolator. In the scheme, the restoring force is modeled by dividing a conservative force and a non-conservative force, and the conservative force is modeled as the Duffing-typed model, in order to completely identify the response characteristics of hardening of a seismic isolator.
 To show the effectiveness of the proposed scheme, numerical examples of the energy transition are demonstrated for applying to a series of the E-defense shaking table tests on a large-scaled base-isolated specimen, when some of lead rubber bearings (LRBs) behave in the response of hardening or breaking under large horizontal deflection. To clarify the feature of the Duffing model-based scheme proposed here, the conventional Equivalent linear model-based scheme is also examined, and the both results are compared in the energy transitions of strain and absorption components. Further, changes in the mechanical energy balance before and after breaking of LRBs are discussed in the energy balance.
 The main results in the paper are summarized as follows:
 1) The Duffing model-based scheme proposed here gives the continuous energy transition of the seismic isolation system toward time-axis even when hardening response is appeared in some of LRBs, whereas in such non-linear regions the Equivalent linear model-based scheme gives accurate estimates only at the final of every half loop of the response.
 2) As compared the both energy transitions of the broken and the unbroken LRBs, it is confirmed that the elastic strain energy of the breaking LRBs related with the conservative forces becomes smaller, and the energy absorption due to hysteresis damping of the breaking LRBs related with the non-conservative forces becomes larger, when some of the LRBs are breaking. These results are considered that the elastic strain energy, that can be transmitted to the next loop if the breaking phenomena are not occurred, is changed into the energy absorption, and as the results the deflection in the next loop becomes smaller than the one in the assumption that the LRBs were not broken. Further, we observed the elastic strain energy of the damaged LRBs is decreased clearly after the breaking. The fact indicates that the storage capacity of the elastic strain energy is reduced by the breaking of LRBs.
 3) According to the results mentioned above, it will be expected the scope of energy balance-based seismic response prediction methods and its design method are extended to non-linear region when hardening or breaking is occurred in some of LRBs.

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 This paper discusses the seismic performance of concrete frame structures in which the upper stories are subtracted for seismic rehabilitation. Existing reinforced concrete buildings and steel reinforced concrete buildings are considered in this study. Most of structural engineers seemingly assume that the seismic performance of such a retrofitted building is improved due to decrement of the total inertial mass. Accordingly, this retrofitting technique has been implemented in old buildings which are insufficient to meet the current building standards law in Japan. This study clarifies how the seismic performance is changed by removing the upper stories through both theoretical approach and nonlinear time history analyses.
 Mid-to-high-rise buildings having seven-to-fourteen stories are employed. It is assumed that these buildings are designed in the current building standards law in Japan. A shear spring model with multi degree of freedom is employed in order to directly assess the distribution of the stiffness and strength of the stories along the height. Both a trilinear envelope curve and a degrading hysteresis rule are considered in each story. The variation of the seismic performance is evaluated in terms of maximum inter-story drift angles (IDA).
 Firstly, fundamental natural periods and corresponding vibration modes are discussed in elastic range. The distribution of the story stiffness is varied in accordance with the increasing of the number of the subtracted upper stories. As a result, eigenvalue analyses show that the approximately triangle shaped vibration mode is changed into a quarter sinusoidal shape after the several mass are removed from the top of the analysis model. This phenomenon is linked to an increase of the IDA in the lower stories in elastic range. Time history analyses also demonstrate that the IDA slightly increases at the bottom story if the natural period of the retrofitted building belongs to the range where spectral velocity is constant.
 Secondary, an evaluation method of IDA without time history analysis is proposed within the framework of the response spectrum method. This proposed method clarifies the relation between amplification factors of the bottom IDA and the number of the subtracted stories. Subsequently, the method is developed with the deviation coefficients of elastic story response and a yield drift angle for each story. Variation of ductility factors are summarized in terms of the number of the subtracted stories.
 Finally, both the proposed method and nonlinear time history analysis conclude that the bottom IDA increases by two times at most in comparison with the original building. The reason is that the ductility factor is spatially concentrated due to subtraction of the upper stories contrary to expectations. In other words, the subtractions of the upper stories possibly deteriorate the seismic performance.

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 Biomimetic technology (biomimetics) has recently attracted a great deal of attention in engineering field. Also, in architecture field, as represented by shell structure, biomimetics has been used for a long time. In recent years, the buildings which floors are supported by the structure such as trees or seaweeds have been built (Tod's Omotesando Building, Sendai Mediatheque). On the other hand, it is conceivable that the topology optimization can be used for biomimetics in architecture field, because it has been observed that the shape obtained by the topology optimization is relatively close to the natural form. Therefore, in this paper, several numerical examples of computational morphogenesis of building structures using IESO (Improved Evolutionary Structural Optimization) method³⁾ are shown in order to verify the application possibility of the proposed method to the biomimetics.
 In IESO method, the design domain is divided in same eight-node brick elements (voxels), and in the optimization process, for solid element, it will be removed if the sensitivity number¹⁰⁾ is less than the threshold value. This threshold value is obtained from the equation proposed in extended ESO^12,13). This equation consists of the mean value of sensitivity number and the average deviation of sensitivity number with a control parameter. In the proposed method, the evolutionary volume ratio (reduction ratio) is given as an input data, and this control parameter is determined automatically in the program so as to satisfy the given reduction ratio approximately. Furthermore, in this paper, finishing algorithm is added to IESO. In this algorithm, first, the converged solution obtained by IESO is input, and then, the elements about 5% of the total elements of design domain are added according to the rule of CA method. Specifically, in order from the element which the sensitivity number is the greatest, the elements of the von Neumann neighborhood are added, and if the number of additional elements is greater than 5% of the total elements of design domain, this program is ended. Finally, the calculation of IESO is executed again with the smaller reduction ratio than the initial analysis (about 1/5～1/10).
 Several numerical examples have been shown in order to demonstrate the effectiveness of the proposed method, and the effectiveness for the application to the biomimetics. By the numerical example which is used for design competition for a new train station for Florence (Fig. 3), it is shown that natural and simple topology can be obtained by IESO (Fig. 4), and it is also shown that if the finishing algorithm is added to IESO, the compliance of the solution obtained by IESO is less than CA-ESO (Fig. 5～8). (It was shown in the previous paper³⁾ that the compliance of the solution obtained by SIMP is greater than CA-ESO.) In the next numerical examples, the structural morphologies which support the single or multi flat slab from various base support points is generated using IESO (Fig. 9～18). From these examples, it is shown that the structural morphologies like natural trees can be generated by IESO.
 It is concluded from these examples that IESO is one method which can be used for applying biomimetics to the building design.

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 Removing formworks early is in great demand for economic reasons, because removed formworks can be reused for upper stories and construction period can be shortened. Many researches on this topic have been done in both material and structural fields. However, the bridges between the two fields are rare.
 In this research, five specimens of reinforced concrete (RC) slab are tested applying sustained bending moment in summer. The specimens are sprinkled with water in the morning after the concrete casting and demolded after three days. The upper surfaces of the specimens are exposed to sunlight and rain for 138 days while loading. The test parameter is the magnitude of the bending moment: zero, -0.5M_c', -1.0M_c', -1.5M_c and +1.5M_c', where M_c is the moment at flexural crack and “–” or “+” indicate the upper surface is subjected to tension or to compression, respectively. Figure 2 shows the reinforcement. Figures 3 and 4 show the loading setup. After the exposure of five months, one of the specimens is cut as shown in Figure 5 to investigate the stress-strain relationship of the concrete near the top and the bottom of the specimen. The following findings are obtained from the results of the experiment. In the following discussion, the computed values are obtained using AIJ Guidelines and assuming that the concrete of each specimen is homogeneous and that the humidity at the upper and lower surfaces of each specimen is same as that of the open air.

 (1) At the age of 194 days, the compressive strength of the concrete of the upper part of the specimen was about 50% of that of the lower part (Figure 8). Young's modulus of the upper part was about 60% of that of the lower part (Figure 8).
 (2) The shrinkage strain of the lower part of the specimen without bending moment agreed with the computation, whereas that of the upper part was negligible (Figure 19a). As a result, the specimen warped to upwardly convex.
 (3) The compressive strains of the lower part of the specimens with negative bending moment less than cracking moment agreed with the computation, whereas the tensile strains of the upper part were larger (Figures 12b and 12c). As a result, the curvatures of the specimens were approximately twice of the computed values (Figure 13a). The differences between the observed curvatures and the computed ones were much larger than those between the computed values assuming the demolding at the age of three days and those at 28 days.
 (4) In the case of the specimen where upper part was cracked in tension, the bond stress between the concrete and the top bar was 2 N/mm² after applying load, which decreased to almost zero after four months (Figures 17 and 18). On the other hand, the bond stress of the bottom bar was 6 N/mm² even after four months (Figure 17). As a result, the curvature and the crack widths of the specimen under negative moment were 1.5 times of those of the specimen under positive moment.
 (5) The third and fourth conclusions stated above indicate that the effect of the curing condition at the upper or lower surface is larger than that of the age of demolding (3 or 28 days).
 (6) The curvatures of all the specimens after 30 years were estimated extrapolating the observed curvatures. The estimated curvatures were between six and twelve times the computed elastic ones as shown in Figure 18. These ratios agreed with the previous researches.
 (7) The rainfall of 30 mm caused the decrease of the shrinkage strains both at upper and lower surfaces of the specimens (Figure 19). The rainfall did not affect the tensile strains of the cracked concrete. As a result, the curvatures of the cracked specimens decreased after the rainfall.

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 1. Introduction
 The long period and long duration ground motions of the 2011 Tohoku Earthquake caused large deformations in tall (> 80 m) braced steel moment frames. Many engineers and researchers have claimed the damage observed at the beam-ends in these high-rise buildings. Thus, one of urgent tasks is to develop a simple method for screening vulnerability of the beam-ends in braced steel moment frames. Some researchers have proposed several evaluation methods to capture damages at the beam-ends. In this paper, the validity of those methods is investigated, considering fracture of braces, and a simple is proposed that does not require time consuming time history response analysis.
 2. Response of Braced Steel Moment Frames under Long Period and Long Duration Ground Motion
 First, an approximately 85 m height building model is created to examine the accuracy of the proposed method for evaluation of the beam-end damage considering the brace fracture. 10 long period and long duration artificial ground motions, scaled to 3 kinds of velocity spectrums: 160,120,80 cm/s, and 2 observed ground motions, scaled to the velocity spectrum of Building Code in Japan, are adopted as input ground motions. This analysis suggests that the damage distribution of the beam-ends is similar to the story drift distribution. Observation of previous analysis shows that damage of the beam-ends with a weld access hole is frequently larger than those with no hole.
 3. Accuracy of Proposed Damage Evaluation Method by Previous Researcher
 The accuracy of a damage evaluation method using Manson-Coffin rule previously proposed by a researcher (Manson-Coffin method) is investigated. Miner's rule is used for the evaluation of the beam-end damage in the method, which is largely consistent with static testing results. Another evaluation method using local strain at a beam-end proposed by the authors is fitted to the Manson-Coffin method to improve the accuracy.
 4. Reference Ductility Ratio for Damage Evaluation
 The number of cycles at each ductility ratio is required to evaluate the damage of the beam-ends using the Miner's rule. This method involves running a time history analysis program. Several ductility ratios are introduced as a reference to reduce calculation time for the damage evaluation of the beam-end. Damage values of the beam-end calculated by one of the reference ductility ratios are consistent with those by the time history response results within a margin of error of plus or minus 30%.
 5. Index for Screening Vulnerability of Beam-ends in Braced Steel Moment Frames
 The energy ratio is introduced, defined as the earthquake energy spectrum VE to the maximum velocity spectrum S_v. For R_E = 2.0 - 3.5 and a maximum velocity is close to 160 cm/s, the beam-end fracture is likely. R_E is promising an index to determine the damage of the beam-end.
 6. Conclusions
 This research investigated the damage evaluation of beam-ends in braced steel moment frames during a long period and long duration motion. The results are summarized as follows.
 1) The damage distribution of the beam-ends is likely to be similar to the story drift distribution. The damage of the beam-end with a weld access hole is frequently larger than that with no hole.
 2) Damage values of the beam-ends calculated by one of the reference ductility ratios are consistent with those by the time history response results with a margin of error of plus or minus 30%.
 3) When the maximum velocity is close to 160 cm/s and the R_E ranges from 2.0 to 3.5, the beam-ends are likely fracture.

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 Square hollow section members such as square steel tube members and box section members are commonly used as columns in structural steel buildings. Their structural performance during earthquakes significantly affects the seismic capacities of the buildings. The square hollow section members used as columns are subjected to bending shear force during earthquakes. Local buckling determines their large deformation behavior, except for fracture. Therefore, it is necessary to investigate the large deformation behavior of the members under bending shear force governed by local buckling for an accurate evaluation of the seismic capacities of the buildings. Although numerous studies have been conducted on the local buckling of the members under bending shear force, the local buckling determinant is not sufficiently understood. Various factors affect the large deformation behavior of the members. The effect of member shapes and loading conditions and the effect of material and geometric imperfections on the large deformation behavior under bending shear force have not been sufficiently investigated. Consequently, the ultimate strength and plastic deformation capacity of the members under bending shear force have not been systematically evaluated as a function of member shapes and loading conditions.
 Given this background, this study aimed to investigate the large deformation behavior of the square hollow section members under bending shear force governed by local buckling and evaluate the ultimate strength and plastic deformation capacity as a function of member shapes and loading conditions.
 First, for the evaluation of the ultimate strength and plastic deformation capacity of the members, the elastic local buckling strength under bending shear force was shown. A new normalized width-thickness ratio S_H based on the elastic local buckling strength and full plastic strength was proposed.
 Then, after understanding the elastic local buckling behavior purely determined by member shapes and loading conditions, the large deformation behavior of the members under monotonic bending shear force was examined using numerical analysis and structural testing. The effect of initial imperfections and the effect of loading conditions on the large deformation behavior were shown. The ultimate strength and plastic deformation capacity were evaluated using the normalized width-thickness ratio S_H based on the elastic local buckling strength. The evaluation expressions derived from this study enable the reasonable prediction of the ultimate strength and plastic deformation capacity under bending shear force as a function of member shapes and loading conditions.
 Finally, after examining the large deformation behavior under monotonic bending shear force, the large deformation behavior of the members under cyclic bending shear force was examined using structural testing. Cyclic loading decreases the plastic deformation capacity under bending shear force. However, most of the ultimate strength and plastic deformation capacity under cyclic bending shear force can be evaluated using the evaluation expressions derived from this study. The expressions were derived via the conservative analysis where initial deflections by buckling mode were used as the most unfavorable initial imperfections.

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 The shear strength of multistory shear walls with openings is affected by the opening arrangement in each story because the shear transferring mechanism changes depending on the location of openings in the upper and lower stories. In this study, static loading test and Three-dimensional (3D) FEM analysis for multistory concrete encased steel (CES) shear walls with openings were conducted to investigate the effect of the opening arrangement in two continuous stories on the shear transferring mechanism. Outlines and results of the test and analysis are described in this paper. The validity of the modified strut model proposed by the authors to estimate the shear strength of CES shear walls with openings is also examined using the experimental and analytical results.
 Three CES shear walls of two stories which were about one-third scale were tested. The variable investigated was the opening arrangement. Specimen CWO2 had an opening arranged in the center of wall panel in each story, Specimen CWO3 had an opening eccentrically arranged in the one side of the wall panel in each story, and Specimen CWO4 had an opening in each story which is diagonally arranged between the upper and lower stories.
 The compressive failure of wall panel around an opening in each story occurred in Specimen CWO2. On the other hand, the shear failures of wall panel in the first story occurred in Specimens CWO3 and CWO4. The maximum strength of Specimen CWO4 with diagonally arranged openings was higher than that of Specimen CWO3 with eccentrically arranged openings, when the boundary column adjacent to the opening in the first story was subjected to tension. The shear strengths of CES shear walls with openings calculated by the modified strut model almost agree with the test results. Since the modified strut model cannot take into account the difference of opening location in the upper story, calculated results between Specimen CWO3 with eccentrically arranged openings and Specimen CWO4 diagonally arranged openings were the same.
 3D FEM analyses for CES shear walls with openings were conducted to simulate the experimental behavior and to examine the shear transferring mechanism. The analytical results of shear force versus drift angle relationships and stress transitions at steel flange in boundary beam showed good agreements with experimental results until the maximum strength in all specimens. The analytical result showed that the concrete compressive struts were formed through the wall panels of the second story to that of the first story in Specimen CWO4 with diagonal arranged openings, when the boundary column adjacent to the opening in the first story was subjected to compression. The results also showed that the concrete compressive struts were individually formed in the wall panel of each story due to the effect of tension in a boundary beam in Specimen CWO3 with eccentrically arranged openings and in case that the boundary column adjacent to the opening in the first story was subjected to tension in Specimen CWO4. Thus, the formation of concrete compressive struts obtained from the analytical results almost agreed with that assumed in the modified strut model. Therefore, it is considered that the modified strut model is appropriate as an evaluation method of the shear strength of CES shear walls with openings.

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 To estimate collapse temperature of a steel fame subjected to fire, collapse mechanisms of heated members in the fire compartment room must be clarified. It is well known that there is a possibility that column buckling at elevated temperature triggers overall frame collapse, which must be avoided at fire resistant design. In accordance with the past studies using fire response analyses for the overall frames, an axial load that the buckled column in the fire compartment room has sustained can be redistributed to the peripheral members at the ambient temperature, through shear force of the beams arraigned at upper stories than the fire compartment room. The load redistribution capacity for the overall frame at the fire is defined as 'the fire redundancy', and the redundant frame can avoid the overall frame collapse even if the heated column loses resistant strength. On the other hand, developments of the collapse mechanisms are influence on variations of steel strength of the members, it is, for the reason, possible that unexpected overall frame collapse is triggered, because of changes of the member collapse mechanisms.
 The main purpose of this study is to quantify the variations in the collapse temperatures and probability of occurrence on the collapse modes for the overall steel frames in case of considering the variations in the steel strength. In particular, relationships between the fire redundancy, which is given by a ratio of the shear strengths of the beams at the upper stories to the axial forces of the heated columns, and the probability of occurrence on the overall frame collapse are clarified, by numerical analyses using Monte Carlo (referred to as MC) method. In the MC analyses, the steel strength samples including characteristics of the past coupon test results at the elevated temperature are used. They has been proposed by the previous study (Ozaki et. al., 2015).
 From minute investigations on the MC analytical results, the following 1)～3) were clarified.
 1) The overall frame collapse occurs at the same time that the heated column at the fire compartment room buckles in case of the small redundant frames. By increasing the fire redundancy, the collapse mode changes to the heated beam collapse, which is the member collapse localized in the fire compartment room. The variation of the collapse temperature for the large redundant frame is equal to that for the beam.
 2) The full redundant frame, which is the stable frame after the buckled columns lost their resistant strengths at the high temperature, is developed in the case of the large fire redundant frame. The probability of occurrence depends on the variation in the steel strength of the beams at the upper stories than the fire compartment room.
 3) It is possible that the collapse modes of the heated members in the fire compartment room are changed by the degree of variation of steel strength at high temperature. Controlling those collapse modes at the fire resistant design is difficult, particularly, in the case when the collapse temperatures among the heated members are close. On the other hand, by increasing the fire redundancy, the probability of occurrence of the overall frame collapse becomes small, and the controlling collapse mode design to avoid the overall frame collapse becomes easy.

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