The harvesting of river and ocean sand, which are used as fine particulates in the manufacturing of concrete is restricted due to environmental safety concerns, which is why crushed sand is now used instead. However, crushed sand has problems stemming from its large fineness modulus. On the other hand, due to recent changes in social conditions, the ratio of thermal power generation in Japan has increased. Furthermore, for reasons involving the long-term stable supply of resources, it is predicted that the amount of coal-fired thermal power generation will continue to increase, and therefore the amount of fly ash (hereinafter “FA”) generated in the process will also continue to increase. For this reason, in consideration of the environment, measures must be taken to effectively utilize FA.
 One of two possible solutions to the problem mentioned above is to mix FA into the sand (hereinafter “FAS”) when mixing the concrete in order to supplement crushed sand’s insufficient amount of fine particles. We investigated about carbonation property of concrete using FAS by accelerated carbonation test and X-ray diffraction analysis. As a result, the following conclusions were drawn.

 1) When we compared carbonation depth and carbonation rate coefficient of concrete using the FAS and mixed sand, at the same water cement ratio, carbonation depth and carbonation rate coefficient were common to standard curing and atmospheric curing, and there was no pronounced difference.

 2) In 50% of water cement ratios, as a result of having examined the influence that a keeping period of the FAS gave to carbonation property, a keeping period was the comparison of the carbonation rate coefficient of concrete in seven days and 90 days and, as for the remarkable difference, was not admitted.

 3) About concrete after the accelerated carbonation test end as a result of XRD analysis, in the sample of the center, because quantity of Ca(OH)₂ was smaller than concrete using mixed sand, concrete using the FAS was able to confirm consumption of Ca(OH)₂ by the pozzolanic reaction of the FA. In addition, in samples of the surface sections, concrete using FAS had a smaller quantity of CaCO₃ than concrete using mixed sand.

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 In the late 1980's, a national project of super high-rise reinforced concrete buildings using high strength and high quality concrete and reinforcing steel was promoted by the Ministry of Construction of Japan. The project was simply referred to "New RC". This project aimed at producing high strength and high quality concrete of the specified from 30 to 120MPa and high strength and high quality reinforcing steel bars of yield strength from 400 to 1200MPa.
 After that many experimental data and knowledge of high strength concrete were provided by many researchers. In the middle of 1990's, high strength concrete of the specified 60MPa Class had been used for high-rise reinforced concrete buildings. And high strength concrete of the specified 100MPa Class had been used for high-rise reinforced concrete buildings in the late 1990's. However, long term data of high strength concrete that cannot obtain by accelerating tests was not collected sufficiently.
 This paper deals with long term data of high strength concrete. Mechanical properties of 80 to 180MPa class high strength concrete at the age of 20 years were examined. Conclusions are as follows. (1) Long-term strength development ratio of sealed specimen and core specimen of mock up column using high strength concrete are increased when water-binder ratio becomes low.(2) Drying shrinkage ratio of 80 to 180MPa class high strength concrete increases between the age of 10 years and the age of 20 years.(3) Core strength and rebound number of mock up column with 80 to 180MPa class high strength concrete are also increased by increase of the age.(4) Elastic modulus and poisson's ratio of 80 to 180MPa class high strength concrete at the age of 20 years can be estimate by conventional estimate equation.(5) Carbonation has not occurred to surface of mock up column with 80 to 180MPa class high strength concrete at the age of 20 years.

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 It has been reported that strength properties are changed by increasing heat, decreasing to a greater extent as the temperature rises. Since concrete subjected to high temperature heating can suffer strength loss, it can also be prone to cracking. However, there have been few reports on cracking in concrete under the effect of high temperature heating. When investigating the cracking behavior, it is considered important to evaluate not only the crack propagation properties but also crack initiation. Fracture mechanics was therefore employed in this study to investigate the fracture properties related to crack initiation and propagation in concrete. This paper reports on the influence of coarse aggregate types on the fracture properties of concrete subjected to high temperatures up to 800°C.
 The fracture properties were evaluated based on tension-softening curves, determined by polylinear approximation through inverse analysis of load versus crack mouth opening displacement (CMOD) curves. Specifically, the evaluation was carried out using the initial cohesive stress and fracture energy, the meanings of crack initiation and crack propagation.  Four different types of rock, sandstone, granodiorite, limestone and chert, were used as coarse aggregate. Concrete was proportioned with a water-cement ratio, target slump, and target air content of 57%, 18 cm, and 4.5%, respectively. The coarse aggregate content was kept constant at 356 liters/m³, while the slump and air content were adjusted by the admixture dosage. Specimens were demolded 2 days after placing, water-cured at 20°C up to an age of 26 weeks, and then subjected to heating followed by testing.
 Two programmable muffle furnaces (inside W310 by D610 by H310 mm) with heaters on both side walls were used for heating. The target temperatures in the furnace were 100, 200, 300, 400, 500, 600, 700 and 800°C. Unheated (20°C) specimens were also tested for comparison. The heating rate was 0.5°C/min. After attaining the target, the temperature was kept for 168 h and specimens were allowed to cool naturally to the level of outdoor air temperature.
 Notched specimens of size of 100 × 100 × 120 mm were used for the wedge-splitting tests. A servo-hydraulic testing machine of closed-loop type was used. The rate of CMOD at the opening mouth was set to 0.02 mm/min.
 The follow conclusions could be drawn on the basis of this study:
 (1) The fracture surface areas of both concrete and mortar affected by high temperature heating linearly increase as the temperature rises. The fracture surfaces of concrete tend to be larger than those of mortar.
 (2) The maximum load of sandstone on the L-CMOD curve scarcely changes up to 300°C, whereas those of other specimens are highest at 100°C. When comparing the maximum loads at the same heating temperatures, that of mortar is higher and that of limestone is lower than the others.
 (3) The tension softening curves express generally decreasing cohesive stress with the increase in the COD. Amid these trends, the cohesive stress of mortar, whose initial cohesive stress is greater than those of concretes, decreases at a slower rate than those of concretes. As to concrete specimens, the reductions in the cohesive stress of sandstone, granodiorite, and chert take on similar trends, but that of limestone is faster than the other concrete specimens.
 (4) At a heating temperature of 100°C, the initial cohesive stress of mortar significantly increases, while those of sandstone, granodiorite, and chert slightly increase and that of limestone slightly decreases. At higher temperatures, the initial cohesive stress decrease.
 (5) Up to a heating temperature of 300°C, the fracture energy of all specimens increases but then tends to decrease as the heating temperature increases.

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 Flexural elastic modulus of plywood and timber for stud in formwork is affected by moisture content, span and reuse of plywood. The influencing factors were studied experimentally and the reduction factor of flexural elastic modulus in the conventional wall formwork was determined. On the basis of this result, a simplified structural design method of conventional wall formwork taking into account intervals of studs and separators and number of reuse of plywood was proposed. Deformations of formwork constituents according to lateral pressure and allowable stresses were illustrated, which can be used for formwork design as well as construction managements.

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 It is very important to predict the airborne chloride ions to be transported from the sea in order to perform endurance design and maintenance. Furthermore, if it is possible to spatially visualize the distribution of the predicted airborne chloride ions, it is beneficial in helping to assess the chloride attack environment. In the above situation, we have proposed the airborne chloride ions estimation formula that taken into account the distance and altitude from the coast. In addition, the proposed formula takes into account the influence of the attenuation of airborne chloride ions. In the previous study (references 25) and 26)), the proposed formula has been approximated using a square law the relationship between the average wind speed and the generated airborne chloride ions. However, airborne chloride ions of Hashima Island in Nagasaki with special coastal terrain, there was a problem that it is difficult to capture the trend of the measured values in the proposed equation using the square-law.
 In this study, we have proposed the generation airborne chloride ions estimation equation using the exponential law. Also we estimated airborne chloride ions to be transported inland by using proposed equation, compared the estimated results with measured results and it was compared to previous studies. Furthermore, we attempt to construct a simple system that can visualize the spatial distribution of airborne chloride ions.
 First of all, in the study of the relationship between average wind speed and the generated airborne chloride ions, the approximation both the square-law and the exponential law were almost the same in Okinawa. On the other hand, in Hashima Island, the approximation compared exponential law with square law, it is possible to better the exponential law capture the trend of more measured results.
 Secondly, we have examined the attenuation coefficient used in equation (1). As the result, it was confirmed that attenuation coefficient considered the effect of shielding of building, the influence of the wind generated by the special terrain, effect of sedimentation rate of splash particles.
 In the study of airborne chloride ions to be transported to the inland, in Okinawa, the estimated value by the proposed formula and the BMS formula of the present study was to obtain a result in good agreement with the measured values. On the one hand, some of the observation points in Hashima Island, it was confirmed that the measured value and the estimated value does not match. However, the proposed equation in the study (Equation (1)) was able to capture the overall trend of the measured values.
 Finally, we visualized the airborne salt transport situation by using the estimated results of the proposed formula. In the created map of transportation airborne chloride ions, it is possible to take into account the distance from the coast, altitude, the building height. Also, it can be spatially visualized.

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 When extreme large earthquake occurs, a base-isolated building may collide with its surrounding retaining wall. To evaluate precisely the acceleration response of superstructure and the deformation of base isolator, resistance characteristics of a retaining wall with back soil should be made clear. In this study, shaking table tests of model base-isolated building are carried out to investigate the collision with building and retaining wall. We analyze the collisions in detail compared with experiment results and its simulation analysis by 3D-FEM. Furthermore collision responses of an existing base-isolation building are analyzed by 3D-FEM focusing on height and width of retaining wall, rigidity of back soil and nonlinear of retaining wall.
 The obtained results are summarized as follows.
 1) By the shaking table tests of base-isolated model building and its simulation analyses, it is cleared that the height of retaining wall effects to acceleration response of building and its restoring force. The lower height of retaining wall reduces acceleration response of building because of the progression of plasticity of retaining wall and back soil.
 2) Collision analyses of an existing base-isolated building show that stress concentrations occur at the bottom of retaining wall and contact area at the corner of building. In the collision with building, the center part of retaining wall contacts at the bottom of building, however the corner part of that contacts along the building foundation. This is because that flange parts of retaining wall inhibit the deformation of that. Therefore flange parts of retaining wall influence greatly to the deformation mode and the maximum strength of retaining wall.
 3) Parametric analyses considering collision speed, height and width of retaining wall and rigidity of back soil show the following results. The collision speed effects to the increase of yield stress of retaining wall because of the difference of its deformation mode. In comparison with the height of retaining wall, the width of that effects larger to the strength of its restoring force. Rigidity of back soil increases slightly the maximum strength of restoring force of retaining wall.

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 The 1855 Ansei-edo earthquake was estimated to occur beneath Tokyo metropolitan area and the seismic intensity there was 6 upper. There are several studies on the hypocenter, the mechanism and the magnitude of the event, but are still unknown factors. No broadband source models which can simulate the seismic intensity in both the Tokyo metropolitan and regional area were proposed. In this study, we estimate the broadband source model and the strong ground motions including surface waves as well as S-waves by the forward modeling of the seismic intensity scale using the empirical Green's function method.
 The patterns of seismic intensity distribution of the 1855 Ansei-edo earthquake are not concentric due to complex structure under the Kanto district. Therefore we firstly calculate the seismic intensity of M5-6 earthquakes occurred beneath Tokyo metropolitan area using K-NET, KiK-net and JMA95-type strong motion records. The distribution of the seismic intensity of the Mw5.9 earthquake occurred in northwest of Chiba prefecture on July 23, 2005 agrees best with the patterns of seismic intensity distribution of the 1855 Ansei-edo earthquake. Then we estimate the broadband source models composed of strong motion generation areas SMGAs and background using three earthquakes including this earthquake (050723) as element events. We assume Mw7.1 and estimate locations and sizes of two SMGAs with the same stress drop by forward modeling of seismic intensity distribution. The rupture starting point is also estimated. The seismic intensity estimated using 050723 agrees best with the observed seismic intensity from Tokyo metropolitan area to 200 km far beyond Kanto district. In the best model we assume a high-angle reverse fault in northwest of Chiba prefecture as an intraplate earthquake of the Philippine Sea plate based on the F-net CMT solution and the depth distribution of the aftershocks of 050723 (Koketsu and Miyake, 2005). The estimated centroid depth of SMGAs is 60 km. The short period spectral level A is the estimated using three earthquakes as element events are almost the same. We also estimate the broadband source models assuming Mw7.0 and Mw7.2 using 050723. The A estimated assuming Mw of 7.0, 7.1 and 7.2 is almost the same and the seismic intensity distributions are similar to each other. This result means that A is the influential parameter to seismic intensity but Mw is not so much. The A of 6.8×10¹⁹ [Nm/s²] of the 1855 Mw7.0-7.2 Ansei-edo earthquake is larger than A derived from the M0-A relation for interplate earthquakes of the Pacific plate (Satoh, 2010) and is slightly smaller than that for intraplate earthquakes of the Pacific plate (Satoh, 2013). The absolute value of A is comparable to A estimated for 1923 MW7.9 Kanto earthquake (Satoh, 2016).
 Strong motions in the periods of 0.05 to 10 s at the engineering bedrock are calculated by the 1-D linear analysis from the strong motions estimated at the surface from the best broadband source model with Mw7.1 using 050723. The strong motions at the surface are estimated using the revised equivalent linear analysis code DYNEQ by Yoshida. The pseudo velocity response spectra of east-west component at the engineering bedrock at Chiba, Otemachi and Shinjuku are slightly larger than those estimated for the 1923 Kanto earthquake (Satoh, 2016) in the periods of 0.6 to 2 s and the building standard law notification spectrum for the level-2 ground motion in the periods of 1 to 2 s. The peak ground velocities at the engineering bedrock at three stations are comparable to those during the 1923 Kanto earthquake, but the velocity pulses with periods of 1 to 2 s are more predominant than those during the 1923 Kanto earthquake.

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 Simplification of earthquake ground motion using pulse waves has been studied to observe pulse-like ground motion. These simplified pulse waves have been utilized in studies of seismic isolated and tall buildings. Simplification of observed waveforms can also be utilized to identify a source model from a series of observed ground motions. Thus, establishing a simplification method is important. Most existing methods are based on extraction of waveforms by wavelet analysis. However, these methods have two main limitations: (i) they focus on non-stationary components; hence, stationary components are not extracted, and (ii) a wavelet for extraction does not have a well-defined period and amplitude, and does have a constant phase.
 First, the proposed method was formulated. In order to solve problem (i), the method extracts waveforms using multiple wavelets, as opposed to existing methods that use only one wavelet; for solving problem (ii), the wavelet is defined as the product of a sinusoidal waveform and a time-domain filter. The filter passes through a central region to clarify the definition of both period and amplitude. The shape of the filter is defined and can be changed using a non-negative integer, N. The proposed method selects and extracts optimum waveforms that minimize the sum of the squares of error using multiple wavelets that have arbitrary phase α and various N. When N has a small value, and α is a constant, the proposed method coincides with typical wavelet analysis. Then, the method extracts a local and non-stationary waveform. When N asymptotically approaches infinity, the method asymptotically approaches Fourier analysis. Then, the method extracts a repeat-cycled and stationary waveform. The method, therefore, can extract an appropriate waveform depending on the original waveform.
 The proposed method was applied on an acceleration waveform observed at Japan Railway Takatori station during the Kobe earthquake in 1995. Analytical cases 1, 2, and 3 used wavelets with N = 0, 1, and 2, respectively. Analytical case 4 used all wavelets with N less than 30. After extracting the optimum waveform, the remaining waveforms were repeatedly extracted 50 times. Comparison of the synthesized waveforms of the first 10 extracted waveforms for cases 1-4 showed that the original waveform was best reproduced by case 4. Among the proposed wavelets, residual displacement was observed only for N = 0. Only the first of the first 10 waveforms was extracted with N = 0. This implies that residual displacement primarily occurred in the region of the first extracted waveform. The transition of error against the extracted number shows that cases 1 and 2 were better than case 3 initially; however, case 3 was better than cases 1 and 2 when the number exceeded five. Case 4 was the best for any extracted number. The method was also applied to a frequency-swept sinusoidal waveform. The transition of error against the extracted number showed that cases 3, 2, 1 were good, in this order, for numbers less than 35. Wavelets with a small N value could not efficiently extract from a stationary waveform. Again, case 4 was the best for any extracted number. The advantage of case 4 over case 1 was larger for this waveform than that for the above earthquake waveforms. The frequencies of the extracted waveforms agreed well with those of the original waveform.
 The proposed method extracts essential waveforms from earthquake ground motion. Thus, this method can be utilized to resolve a waveform into various waveform components caused by different propagation paths. Moreover, because this method can reproduce a waveform with a small number of parameters, it can be applied as a compression technique for sound and image.

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 We have reported an active seismic response control system by making use of an energy conversion in damping devices³⁾. In this paper, we propose a system where energy conversion and reuse are interacted, we call it ‘interaction system’ here, and evaluate its characteristics through seismic response analyses. In the ‘interaction system’, responses are drastically reduced by the control gain where energy input and output are balanced. In addition, in comparison with an ‘independent system’ shown in Part 1³⁾, the ‘interaction system’ shows the similar response reduction effect by this control gain. The damping force and velocity of the passive devices are about 60% of the ‘independent system’, and the control force and velocity of active devices are equivalent. The ‘interaction system’ shows a possibility that it can construct the total system compactly, compared with the ‘independent system’. The proposed system can realize the active seismic response control system against large earthquakes where its application in the actual stage is supposed to be difficult.

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 A rotary press-in pile with wings has advantages to get large vertical bearing capacity for its pile diameter and to reduce the amount of soil excavated for its installation. On the other hand, it has been concerned that the rotary pile might cause weakening of the soil around the rotary pile. Even in the case of clay, it has not been confirmed that such weakening of the surrounding soil would be caused by peripheral soil displacement during pile installation and/or the passage of pile wings. In this paper, a series of experiments was performed to grasp the behavior of a rotary press-in pile horizontally loaded, and the property changes of surrounding soil by installing a rotary press-in pile with wings. In the experiments, the execution of pile installation was managed with constantly maintaining the ratio of s/p in the range of 1.0±0.1, where s is the penetration length of pile rotated by one revolution and p is the helical pitch of its pile wing.
 The experiments were carried out at two different sites, where one was the site depositing an alluvium clay layer and the other with a diluvial loam layer. In the experiments, in order to investigate the properties of soil around a pile, the measurements of bulk density and water content were conducted for soil samples taken from the vicinity of the pile shaft with specially equipped apparatus. And also, the one dimensional consolidation test, and the tri-axial compression test were performed for samples taken in the vicinity of the pile were performed. The lateral loading tests, apparatus of one of which was directly equipped with pile shaft and the other of which was normal test, were carried out.
 In order to compare the differences in the pile installation methods, the laterally loading tests for the pile installed by rotation method and the buried pile were carried out.

 As a result of this study, the conclusions are as follows.
 1) In the soil around a rotary press-in pile with wings, density increase and stiffness decrease were caused by soil displacement and wing passage.
 2) The range where soil density increases depends on the compressibility of soil.
 3) The stiffness decrease of the soil in the vicinity of pile is more strongly affected by soil displacement than by wing passage.
 4) The installation method of the rotary pile constantly maintaining s/p can provide appropriate installation without the occurrence of void around the wing although there seemed the gap between the pile shaft and the ground in any case.
 5) The coefficient of horizontal subgrade reaction for the rotary pile with wings became 0.54-0.74 times as large as that for the buried pile due to the gap between pile shaft and ground, and the stiffness decrease of the soil in the vicinity of the pile.

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Seismic response of raised lattice shell roofs is known to be complicated due to the coupled vertical response when subjected to horizontal ground motions. The authors have proposed a simple response evaluation method for spherical domes and cylindrical shell roofs using amplification factors and equivalent static actions. However, it has only been verified for a limited number of shapes, which do not include the increasingly popular freeform roof topologies. In this paper, the previously proposed method is expanded to freeform structures generated with optimization methods and numeric form finding. The effect of parameters such as the roof shape, rise/span ratio, and supporting substructure on the seismic response is studied, and the simple evaluation method extended and verified for freeform shapes.

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 In Japan, there are a lot of traditional timber buildings which fit the history, the culture and the environment in each area. In our investigation of traditional timber houses in the important district of groups of historic buildings, mud walls which have various specifications and crosspieces called Nuki and structures which consist of tall hanging walls and beams called Sashigamoi (called large hanging walls in this study) were found. Timber frame structures with hanging walls are very important factor to think of seismic safety of timber buildings because they can lead to collapse of the whole buildings by breakage of columns at joints of the lower end of hanging walls. Although static loading tests and shaking table tests of timber frames with hanging walls have been conducted, the failure behavior and deformation performance have not been analyzed in detail.
 As the current methods of seismic capacity evaluation, “Implementation Guidance for Basic Seismic Assessment of Important Cultural Properties (Buildings)” proposed by Agency for Cultural Affairs and “Seismic Evaluation and Retrofit Methods of Wooden Houses” proposed by the Japan Building Disaster Prevention Association have been used. Although the consistency between the current methods and the test results has been examined, the hanging walls of the specimens are not tall and the analysis is not enough about shear force and deformation performance of the columns, flexural strength of the columns and limit deformation evaluation of the frame structures with hanging walls.
 Therefore, the purpose of this study is demonstrative elucidation of dynamic characteristics of timber frame structures with large hanging walls in order to construct a reasonable and practical seismic evaluation method. First, we conduct static loading tests of timber frame structures with full walls or large hanging walls. The height of the full wall specimens and the large hanging wall specimens is 2.70m and 3.87m, respectively. The span length of the specimens is 1.82m. The height of hanging walls is 1.80m. The specification of walls and the number of spans are experimental variables. Second, we analyze damage states and mechanical characteristics of the specimens and their elements such as mud wall, columns and Sashigamoi. Finally, we reveal the applicability and problems of the current methods based on the test results.
 The major findings obtained from the research are summarized as follows:
 a) Different specifications of Nuki do not make much difference of the hysteresis characteristics of the full wall specimens in spite of the different failure states of walls.
 b) The hysteresis characteristics of the large hanging walls can be calculated using the hysteresis characteristics of the full wall specimens which have the same specification of wall.
 c) Timber frames with hanging walls do not lose the restoring force immediately after breakage of columns because the broken columns have the restoring force. Within this study, rotational angle of the specimens is more than about 1/15 rad when the restoring force decreases to 80% of the maximum value.
 d) Shear force of a column is not depend on only the sum of half of the distances from the column to the adjacent columns on the both sides, because shear force is affected by the sectional performance and Young's modulus of the column, the location of the column against the loading direction and breakage of the surrounding columns. In addition, we indicated that it is need to consider rotational deformation of columns at column-Sashigamoi joints in evaluation of deformation of timber frames with hanging walls. From the above, it is revealed that there is room for improvement on the current methods in seismic performance evaluation of timber frames with large hanging walls.

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 The purpose of this study was to obtain the fundamental values which were required to establish the decisions for the fire resistance verification method in case of localized fire scenario. The species of wood samples tested in this study was limited to Sugi (Cryptomeria japonica) controlled at the moisture content of less than 15%.
 In Chapter 1, the present circumstances of the fire resistance verification method since 2000 when Building Standard Law of Japan had been revised was explained. And the definitions for fire resistive buildings and what kind of values needed for this method were put in order. Then previous studies regarding the ignition, burning and the charring behavior are reviewed and the content of experiments carried out in this study was introduced
 In Chapter 2, the ignitability tests and cone calorimeter tests (CCM) at the incident heat fluxes of less than 20 kW/m² from 20 to 30 minutes were conducted. The lowest radiant heat flux to cause ignition within 30 minutes was found to be from 13 to 15 kW/m² because neither glowing nor flaming was observed at the incident heat fluxes of less than 13 kW/m². And the linear function, which could lead to the time to ignition (tig), based on the date by plotting 1/√tig against incident heat fluxes was proposed. On the other hand, the temperature, which had been quoted as one of the determinants for ignition typically, was not suitable to the criterion to ignite because even if the temperature reached to 260°C or more on the surface of the test samples, ignition didn't occurred or delayed because of the lack of the amount of enough vaporized fuel to cause ignition below 20 kW/m².
 Then even if ignition occurred, each test sample was extinguished automatically at the incident heat fluxes of 15~20 kW/m². And it was found that the char depth could be obtained by the linear regression that were made through the char depth to the product of the given incident heat fluxes by the difference between the experimental period and the time to ignition. But the darkening was observed on the surface of the samples even if not ignited, and the temperature at the depth of 5mm from the bottom of the char layer was also measured more than 180°C. These phenomena could influence to the strength and the toughness of the wood.
 Therefore, in Chapter 3, the static bending test and impact test of small pieces of wood exposed to heating at 120°C, 150°C or 180°C for 20 minutes and stored later in the desiccator at 20°C for several days were performed. And the date from the experiments was compared with the date from the test samples not to be exposed to heating in order to investigate the possibility of deterioration of the structural performance of wood by heating. And by the comparison using statistics, it was not seemed that the strength and the toughness of wood would fall. In addition, the effect of the thermal degradation characteristics of wood on the duration of load was considered by the previous study and the date from the tests conducted in this report. And the heating at below 150°C was unlikely to degrade the structural performance of wood.
 Consequently, we propose the equation for the time to ignition, the equation for the char depth and the effective section size of the beams to check the structural performance as the decision for the fire resistance verification method in case of localized fire scenario for 20 minutes.

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 Timber structures require many joints connecting the structural columns and beams. Unfortunately it is generally difficult that timber structures have rigid joints. Due to external forces, the rate of deformation at the junction of the deformation of structures increases. Therefore the effect of deformation of joints in wooden structure must be taken into consideration.
 The objective of this study is to verify the approximate analysis for the load-slip characteristics of drift-pinned joints of steel plate inserted by beam-model. The approximate analysis model is composed of divided elements of beam model and supports that have wood spring concentrated on each node while using stiffness matrix of beam modeling general stiffness equation.
 The result of linear analysis with drift-pinned elements whose length is less 0.5 d(d: diameter) was almost same as the solutions of elastic foundation beam theory.
 In order to make the comparison with detailed experimental results, a rigid zone section was set on the base end of an analysis model to restrain the deformation of the thickness of the steel plate. We verified the central loading tests by analyzing a beam model with tri-linear rotation springs and thereby confirmed the validity of the nonlinear model of drift-pin.
 Nonlinear analysis with divided elements of beam model that has tri-linear rotation spring, and wooden embedding spring that has characteristics of 3P-exp function was carried out.
 Accuracy of approximate analysis was examined by utilizing both divided elements and displacement analysis step as parameters. To improve upon accuracy of analyses in the yield hinge region, the number of elements divided at the range of the part of the base end of analysis model is increased.
 Experimental results and analyses with embedded strength formulas using wood specific gravity were compared. The results of this experiment were mostly distributed between the upper and lower limits of analysis results with embedding strength formulas. For analysis model to evaluate the experiment results, it is essential to select the standard embedding strength rather than to be accurate analysis by the number of elements divided
 The strain measurement of drift-pin and nonlinear analysis can show the bending yield point of the moment(My).
 On the allowable stress design of timber structures, the damage limits displacement to the short acceptable shear strength(Pa) of joint in earthquake is significantly affected by the relations between strength(Pa) and strength(Pp) that yield hinge(Mp-strength) occurred.

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 It is important to arrange shear walls well-balanced in a plane, in order to keep balanced stiffness on seismic design of wooden houses. Especially, in case of the house with some high strength shear walls, it sometimes cannot show corresponding shear force to wall magnification, because of joint breaking or planner eccentricity. On Technique of Wall Quantity Evaluation, one of simplified seismic design method, we must check the eccentricity of whole house.
 There are some previous studies about eccentricity behavior of the wooden houses; such as the phenomenon caused under horizontal load on the wooden house arranged the walls unbalanced, and so on. But there is not the study about influence on the perpendicular frame by in-plane eccentric wooden wall under horizontal loading.
 Until the present, the wooden walls have been thought to be able to ignore in-plane torsional moment because of flexible structure. However, recently, developing new high strength materials or construction methods, and being possible to design the plane and the elevation freely, the demand of high strength shear walls is growing gradually. Then it is very meaningful to understand the phenomenon by in-plane eccentric wooden wall.
 Based on the above, this paper reports the results of the verification on the out-of-plane force by in-plane torsional moment, to understand the phenomenon impacted on the perpendicular frame by in-plane eccentric wooden wall, as primary subject, based on static loading test for three structural plywood walls.
 Major findings from the research are as follows:
 (1) First, based on torsional theory by Wagner and St.Venant, as an open cross section member given torsional moment, the estimated formula were led on initial stiffness and out-of-plane force from columns. The condition changing out-of-plane force is clarified by parametric study.
 (2) Second, static loading test was conducted on three structural plywood walls; in-plane eccentricity as parameter. The out-of-plane force of the open cross section wall is larger than one of the closed cross section wall. The value of the walls targeted in this paper has about 6% of the horizontal load.
 (3) Finally, the above formula was found to estimate test result extremely precise. It is found that large out-of-plane force occur to some open cross section walls with large eccentric length, even if wall magnification was low. The rate of out-of-plane force for horizontal load is same extent between the open cross section walls of same size, in spite of horizontal force.

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 The AIJ standard and guidelines require checking bond stress around reinforcing bars in R/C beam, which targets are not only cut-off bars but also bars placed through the span and anchored at the both ends of the beam. On the other hand, there are several studies on shear strength of R/C members fail in bond splitting, and shear strength formulas for the bond splitting failure were proposed. One is a practical method which origin is Ohno & Arakawa formula, which was based on experimental studies and proposed in 1960. However, application of the Ohno & Arakawa formula to high strength R/C member is not examined sufficiently. The others are based on shear resistance models those are superposition of arch and truss mechanisms and are solved by the theory of plasticity. The models can be divided into two types, which are called type A and B hereafter, according to assumption of concrete strut angle in the truss mechanism. These types are summarized in “Design Guidelines for Earthquake Resistant Reinforced Concrete Buildings Based on Ultimate Strength Concept” published by AIJ in 1990. In the type A, the concrete strut angle is decided as the solution gives the largest value, and shear strength under a yields mode of bond splitting and yielding of shear reinforcement can be calculated. However, the bond splitting strength and shear strength are evaluated separately in the present design method. It is observed in some experiments that R/C beams fail in bond splitting with shear cracks and yielding of shear reinforcement. If it is verified by test results that considering the yield mode of bond splitting and yielding of shear reinforcement is significant for shear strength, it means necessity of reviewing the present design method.

 In order to investigate significance to consider the yield modes of bond splitting and yielding of shear reinforcement when shear strength is calculated, calculations based on the types A and B models are examined by comparing with test results in the previous studies. The calculations are given by applying the bond splitting strengths to the shear resistance model that consist of arch and truss mechanisms. The bond splitting strengths are simplified by transforming into strengths of shear stress on bond splitting plane. Four yield modes can be represented by adopting the type A, which are states: shear reinforcement yields; bond splitting plane yields; the reinforcement and the splitting plane yield; and the both components don't yield. The type B does not include the state that both the reinforcement and the splitting plane yield. When the type A model is compared with the type B model, the type A model shows better agreement with the test results in the yield modes and the shear strength than the type B. As a result of the comparison, it can be said that effects of increasing shear reinforcement ratio or yield strength of shear reinforcement are different in the yield mode of the bond splitting and the yielding of shear reinforcement. In order to examine the Ohno & Arakawa formula on evaluation of shear reinforcement, calculation result of the formula is compared with the type A model, and these two calculations show good agreement. This result implies that influence of the bond can be evaluated by Ohno & Arakawa formula. Although the yield mode of bond splitting and yielding of shear reinforcement can be expressed by the type A model, there are some problems to evaluate shear strength accurately, for instance: combination of material strength of concrete and reinforcement; influence of cyclic loading and inner supplementary ties; dowel effect of longitudinal bars; and so on.

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 1. Introduction
 It is known that the thin circular steel tube under cyclic torsional moment shows a stable energy absorption capacity. The reason is because its cylindrical shape prevents plate buckling, up to large shear deformation. By taking these advantages, development of the lattice damping wall system has also been carried out. (Fig. 1) In this paper, cyclic loading tests are performed in order to confirm basic mechanical performance of single torsional steel tube for the lattice damping wall system.

 2. Experimental design
 The test parameters are steel grade, diameter-thickness ratio, length-diameter ratio and loading pattern. The standard specimen has 48.6mm diameter, 40mm length, 2.3mm plate thickness, and its steel grade is STK400. The loading patterns are “increasing load” and “increasing load after decreasing load”. Also, specimens without welded-joint are manufactured in order to improve the construction workability. And its damping performance is examined to.

 3. Experimental Results
 The full plastic torsional moment and the initial rotational stiffness of each specimen are almost same as the calculated value. In the case of cyclic increasing load to the torsional rotation angle θ = 1/20, all of the specimens draw stable hysteretic curve of spindle shape. According to the increasing of torsional rotation angle, the value of the torsional moment increases too. Also, compared at each amplitude, as the diameter-thickness ratio and length-diameter ratio becomes small, the strength and energy absorption capacity increases. In the case of monotonic loading, the strength of ST2-8 and SUS1-4 dropped and we can see large buckling displacements on the entire steel tube. In the case of the increasing load after decreasing load, a large difference of the strength between the decreasing load (1 to 8 cycles) and increasing load (9 to 16 cycles) could not be found, so stable hysteretic behavior was confirmed. Moreover, stable hysteretic behaviors in specimens without welded-joint could be confirmed. However, the initial rotational stiffness by experiment was lower than calculated value.

 4. The torsional characteristics of circular steel tube
 The initial rotational stiffness of specimens with welded-joint corresponds well with the calculated value, so it can be evaluated by Equation (2). Therefore, the initial rotational stiffness of the steel tube can be adjusted by diameter, length and thickness. A tendency can be see that strength’s increasing rate increases as the length-diameter ratio is reduced. Also, we can see that strength’s increasing rate increases as the diameter-thickness ratio increases. All plastic rotational angle was less than 0.01 in all of the specimens. The plasticity start time can be adjusted by the length-diameter ratio, diameter-thickness ratio and strength of the steel. It can be seen that cumulative plastic deformation magnification increases as length-diameter ratio is smaller, and the energy absorbing capacity is excellent. In the same degree of length-diameter ratio, the cumulative plastic deformation magnification of LY225 and SUS304 is higher than that STK400.

 5. Conclusion
 The stable history behavior could be found in all specimens with no difference in welded-joint or without welded-joint. It was shown that the yield strength and the initial rotational stiffness of the steel tube correspond well to the calculated value, and the strength and the energy absorbing capacity increase as the diameter-thickness ratio and length-diameter ratio become smaller. However, we found the buckling deformation on the specimen with large diameter-thickness ratio and length-diameter ratio, and the strength of those were decrease.

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 The most widely used beam-to-column connection type in high rise buildings for seismic-resistant frames is the welded flange-bolted web type beam-to-column connection. Most of the studies conducted so far on this connection type have evaluated the maximum bending strength by considering the bearing strength of bolts. This results were reflected in "Recommendation for Design of Connections in Steel Structures" in Japan.
 Recently, it is concerned that long period earthquakes will occur. Under long period earthquake, beam-to-column connection in high-rise building will be subjected a large number of small amplitude cycles of seismic force. Therefore, it is important to investigate the plastic deformation capacity of the beam before engaging the bearing capacity of the bolts. This problem was investigated by several studies using both cyclic loading and shaking table tests for high-rise building structures. However, the effect of the bolts arrangement on the moment transfer of the web was not one of the considered parameters.
 The purpose of this study is to investigate the influence of bolt arrangement and that of the moment transfer efficiency of the beam web on the plastic deformation capacity of beam. For this purpose, a shear plate and the beam flanges are welded to the 50mm thick end plate. Therefore, the out-of-plane deformation of the column plate is not taken into consideration.
 The specimens were tested by cyclic loading. Five types of bolt arrangements were designed by considering the bearing strength and slip critical design strength.
 The conclusions of this test are as follows:
 1) If the out-of-plane deformation of column skin plate can be neglected, the incipient slip critical strength obtained from the relationship between moment transfer of web and the relative rotation angle between the shear plate and web agrees with the calculated values.
 2) The plastic deformation capacity of the welded flange-bolted web type beam-to-column connection under relatively small amplitudes is determined as the minimum value between the slip critical strength and yield strength.
 3) In case with the slip critical strength of friction joint with high strength bolts on web is greater than the yield strength of the shear plate, upper limit of the plastic deformation capacity of the beam was confirmed. These specimens had almost the same number of cycles to failure as a typical shop welded beam-to-column connection.

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 1. Introduction
 The authors have proposed a method to assess the local fracture mechanism of moment frame connections and brace members under cyclic loading directly from global member results, termed the Direct Local Strain Evaluation Method. However, up to now, the accuracy of the proposed method has only been validated under static loading. This research validates the proposed method under dynamic loading with collapse tests.
 2. Test Setup
 A frame composed of a single bay moment frame and a concentric circular hollow section (CHS) brace was assembled for the dynamic collapse test, with LVDT strain gauges installed to monitor fracture of the brace and the beam connections. Initially quasistatic loading tests were carried out to confirm the fundamental mechanical properties of the braced frame specimens. The testing rig included an inertial mass system to simulate PΔ effects large deformation.
 3. Quasistatic and Dyanamic Loading Tests on Braced Frames
 The diameter-thickness ratios of CHS brace of specimens ranged from 42.3 (slender) to 11.8 (compact). In the quasistatic tests, the slender specimens failed by local buckling at the midpoint and ends of the brace member, while local buckling was not observed for the compact specimens. However, when connection fracture governed, the cumulative deformation capacity of the brace was not necessarily determined by just the diameter-to-thickness ratio. In the dynamic loading test, the slender specimens, residual story drift angle was 1/282 rad at initiation of brace fracture, 1/21 rad following fracture of the brace and 1/6 rad once the beam connection fractured.
 4. Numerical Investigation on Simulation of Quasistatic Loading Tests
 A series of FEM analyses were conducted in order to simulate of the quasistatic loading tests, where the member modelled with shell elements. The Direct Local Strain Evaluation Method is largely effective estimating the local strain of the brace member and at the beam connection.
 5. Validity of Direct Local Strain Evaluation Method under Dynamic Loading
 Numerical FEM models were also created to simulate of the dynamic loading test using stick models. The estimated initiation of local buckling was found to be more accurate using truss elements for the brace than by using bending elements. Generally, the post-brace-fracture displacements of a dual brace-moment frame system are much greater than the displacement contribution of local buckling. While local buckling can have a significant effect on the pre-brace fracture displacement, the precise instant that local buckling is initiated has a relatively small effect on the total displacement response of a frame with brace fracture. The proposed method is effectively predicted the braced frame response including the brace fracture under dynamic loading.
 6. Conclusions
 In summary, the following results were obtained:
 1) Local buckling occurred at the midpoint and ends of the brace for slender CHS specimens, while local buckling of compact CHS specimens was not observed in the quasistatic loading tests.
 2) In the dynamic loading test of the slender CHS specimens, the residual story drift angle was 1/282 rad at initiation of brace fracture, 1/21 rad following fracture of the brace and 1/6 rad once the beam connection fractured.
 3) The Direct Local Strain Evaluation Method is effective in estimating the local strain of the brace member and at the beam connection.
 4) The proposed method effectively predicts the braced frame response including the brace fracture under dynamic loading.

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 The non-diaphragm method for joining CHS-column and H-beam simplifies the connection details and facilitates the welding procedures of steel moment frames, while it requires a design method for semi-rigid connection as schemed in Fig. 1. In this study, structural properties of their panel and joint were experimentally investigated.
 Two types of specimen were tested: one is an X-shaped frame whose panel is subjected to shear, and the other is a 3-point bending specimen whose panel is free from shear. The experimental setup and the arrangement of displacement meters are illustrated in Fig. 3 to Fig. 6, and the specimens are listed in Table 1. The steel materials are summarized in Table 2 with their stress-strain curves in Fig. 2.
 The relationships of applied load and overall deformation are shown in Fig. 7 and Fig. 8, and the post-test pictures are shown in Fig. 9 and Fig. 10. It is observed that they are fairly ductile and tough accompanied by ample plastic deformation. The ultimate state of X-frame is governed by joint failure for the non-diaphragm style, while by panel failure partly associated with lateral buckling of beam for the diaphragm style.
 The curves of moment vs. shear angle of the panel in X-frame of the diaphragm type are shown in Fig. 11, from which measured strength and stiffness of the panel are given in Table 3. The method of determining the shear angle of the panel is illustrated in Fig. 12(1). The obtained effective volume of the panel in terms of strength as well as stiffness is found in accordance with the AIJ guideline.
 The curves of moment vs. rotation of the joint in X-frame and 3-point bending specimens of non-diaphragm style are shown in Fig. 13, in that the method of determining the joint rotation are shown in Fig. 12(2). Their joint properties are summarized in Table 4, and compared in Fig. 14. The ratios of strength are around 1.0, which indicates that the joint strength is not influenced by the panel shear. However, the ratio of stiffness is much larger than 1.0, which is attributed to the different actions of beam end moments.
 The strength and stiffness of the joint of the non-diaphragm connection calculated from the formulae proposed by the authors are put in Table 5, and compared with the experimental results. It is found that the predictabilities are satisfactory both for X-frame and 3-ponit bending, which indicates that the formulae are valid irrespective of the existence of shear in the panel.
 The load-carrying capacities of X-frame are shown in Table 6. The max ratio of non-diaphragm to diaphragm is 1.0. This suggests that the shear strength of the panel in non-diaphragm connection is not less than that of the panel in diaphragm connection.
 The shearing stiffness of the panel in non-diaphragm connection in X-frame is compared with that specified in AIJ guideline for diaphragm connection in Table 7. The ratio is close to 1.0, which suggests that the shearing stiffness of the panel in non-diaphragm connection is almost the same as that of diaphragm connection.
 On the assumption that the panel and joint behave independent without any interaction as shown in Fig. 15, the procedure of frame analysis for the cruciform sub-frame of Fig. 16 are extended to the X-frame. The analytical load-deformation curves are well coincident to those of the experiment as shown in Fig. 17.
 Conclusively, the structural behaviors of panel and joint in non-diaphragm CHS to H-beam connection are independent, and then the structural properties of the joint and panel can be calculated by the formulae previously proposed by the authors and the formulae specified in AIJ guideline, respectively.

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Response control retrofit of existing RC buildings with buckling restrained braces (BRBs) assures immediate occupancy performance level after severe seismic events. This method is widely used in Japan and may improve the sub-standard buildings in overseas countries with high building importance factors e.g. school buildings in Turkey. Implementation of BRBs and elastically designed closed-steel frames in seismically deficient such RC frames would provide a much better damage distribution and mitigate the possible residual displacement after an earthquake. This paper describes near full-scale displacement-controlled cyclic testing of five specimens to meet the performance requirements given by the relevant codes in Japan. Special emphasis has been placed on the composite interaction between the RC frame and added elastic frame. Experimental results including hysteretic curves, dissipated energies, crack patterns on the RC elements, and strain histories are promising for the response control retrofit of sub-standard RC buildings located in seismically vulnerable areas.

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 Collisions between vehicles and structures can occur as a result of accidents. Occasionally, fire may break out if the vehicle payload includes oil, fuel or other combustible materials. Low-velocity impacts on reinforced concrete (RC) walls can lead to overall failure in the form of bending fracture or shear fracture, but in order to protect life and property near or inside the structure, collapse isn't acceptable. Moreover, if fire does break out after impact, the fire resistance of the structure must be retained to protect life and property. This means a fire inside or outside the structure mustn't spread to other compartments and spaces nor pass through the walls, and the structure mustn't collapse as a result of fire. Therefore it is necessary to investigate the influence of overall failure on the fire resistance of structures.
 The work of the authors focuses on combined impact and fire. They have carried out an experimental and analytical study on temperatures in concrete plates exposed to fire after high-velocity impact as well as an experimental study on the structural fire behavior of RC walls after high-velocity impact by a hard projectile. The experimental and analytical study reported here is the third step in this research program on impact and fire.
 The study focuses on low-velocity impacts and the structural fire behavior of load-bearing RC walls with short fiber reinforcement exposed to a hydrocarbon fire after such impacts. The study comprises low-velocity impact tests, fire tests on specimens under centrally loaded conditions after low-velocity impacts and numerical analysis of the structural fire behavior of these RC walls.
 The small-scale RC wall specimen was designed not to fail by shear but by bending against the load perpendicular to the wall axis, under the assumption the wall is hit horizontally by a rigid body. Six specimens measuring 300mm in width, 800mm in height and 80mm in thick were made with normal-strength concrete of design strength 24MPa. Deformed steel bars (SD295A) 6mm in diameter were used. Polypropylene short fibers of dimensions 0.05mm in diameter and 10mm in length were mixed into the concrete used for three of the six specimens at a ratio of one percent to the concrete volume.
 Four specimens were subjected to a low-velocity impact. ‘Overall failure’ in this study was defined as the maximum tension strain and residual tension strain of the main reinforcing bars exceeding the yield strain. The impact load was provided using a 150kg weight. In order to find in advance the specific velocity at which overall failure of a specimen occurs, a plain concrete specimen was continuously impacted by the weight at speeds of 0.5, 1.0, 1.5, and 2.0m/s. Based on this, one normal specimen and one short fiber reinforced concrete (FRC) specimen were struck by the weight at 1.5m/s, while one of the FRC specimens was struck by the weight at 2m/s. These low-velocity impact tests clearly demonstrate the advantage of short fiber reinforcement against low-velocity impact.
 Fire tests under long allowable centrally loaded conditions were carried out on five specimens. The two non-damaged specimens, one of plain concrete and the other FRC, exhibited the same fire resistance. Spalling occurred on the plain concrete specimen struck at 1.5m/s, but there was no spalling in the case of the FRC specimen. The fire resistance of the FRC specimen struck at 2.0 m/s was lower than that of 1.5 m/s. These differences in fire resistance among specimens confirmed through the numerical analyses without main re-bars on the heating side of a RC wall. The next stage of the project is to introduce a buckling phenomenon of main re-bar into numerical analysis.

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 When concrete is heated under a sustained load, a large amount of shrinkage occurs to compensate for thermal for expansion. This shrinkage was termed the load-induced thermal strain (LITS), and must be considered when performing a deformation analysis of reinforced concrete structures that are subjected to fire. In the constitutive strain models used in such analyses, the LITS is a function of the concrete temperature. However, the relationship between the LITS and temperature is influenced by the water of the concrete, making it difficult to apply these models to concrete with different water conditions. In the present study, the influence of the curing conditions (air-dried, oven-dried and sealed curing) and water/cement ratios (40%, 50% and 65%) on the LITS was investigated based on results obtained from the transient tests for measuring total thermal strain of concrete specimens. The relationship between the LITS and specimen weight loss was also evaluated in order to develop a comprehensive model for the LITS that is appreciable to concrete with different curing conditions and water/cement ratios.
 In the transient tests for measuring total thermal strain, specimens ware heated at a constant rate of 1.5°C/min. up to 800°C under constant load. The ratio of the constant load to compressive strength of air-dried specimens at room temperature was settled between 0.1 and 0.7. The LITS was calculated by subtracting value of the free thermal strain from the total thermal strain. The heating rate in the transient tests for measuring the weight loss was same as the tests of the total thermal strain.
 The main results obtained from the present study are as follows:
 (1) The influence of the water evaporation on the LITS was evident between 100°C and 200°C.
 (2) The influence of the dehydration and decomposition of the cement hydrate on the LITS was evident above 200°C.
 (3) The LITS due to dehydration and decomposition was larger than that due to water evaporation.
 (4) The relationship between the LITS and load level was seen to be linear, regardless of the curing conditions or water/cement ratio.
 (5) The numerical model for the LITS was proposed as a function of the weight loss of the specimens. And, it was indicated that the proposed model could be appreciable to concrete with different curing conditions and water/cement ratios.

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