In Architectural Institute of Japan, design technique of concrete used for reinforced concrete structure subject to exogenous type salt attack is provided. It is desired that required penetration resistance of chloride ion to concrete is decided based on the actual environment at that design technique. However, it is difficult that preparation of technical data is not enough in current condition. It is one of those reasons that an accelerated test method of chloride ion penetration is not established. Accordingly, the past researchers conducted the experiment with original test methods of various conditions. Therefore, this paper presents the results of the accelerated tests and the exposure tests on the penetration and diffusion property of chloride ion in concrete from literature survey. Literatures are selected by some requirements, accordingly accelerated test reports are 18 and exposure test reports in coastal area are 7. These accelerated test reports were classified into alternating immersion and immersing in salt water.
 In general, it is said that penetration and diffusion properties of chloride ion in concrete follow the diffusion equation. Moreover, this equation is prescribed by two characteristic values which are chloride ion content of concrete surface and diffusion coefficient. At the results of arrangement and examination of literatures data, the characteristic values showed the tendency to change with passing period, and then converge to the constant value at the exposure test. At the accelerated test, immersing in salt water showed that characteristic values change similar with exposure test. Moreover, these tendencies can be expressed with model formulas. At alternating immersion of accelerate test, however, characteristic values were constant from initial stage of test. Furthermore, influences of water cement ratio on characteristic values were little in each test method.
 Relationship of diffusion coefficient with water cement ratio is shown in each specification of Architectural Institute of Japan and Japan Society of Civil Engineers as the relation expressions. In these expressions, diffusion coefficient increases with water cement ratio, and the same tendency was shown in the each test method from this examination. And then, diffusion coefficients of exposure test were distributed near these expressions. At the accelerated test, on the other hand, diffusion coefficients were distributed approximately 10 times of exposure test at the same water cement ratio. Nevertheless, difference of diffusion coefficient by water cement ratio was exceedingly smaller than the dispersion of experimental values.
 In the accelerated test, the method of immersing in salt water is the most simple and showed similar tendency with the exposure test in this examination. Accordingly, in this paper, the studies were conducted under the test conditions of the immersing in salt water of accelerated test, to estimate the penetration and diffusion properties of chloride ion in concrete. Consequently, chloride ion content of concrete surface was influenced by NaCl concentration of salt water immersed, however diffusion coefficient was not influenced by it. Moreover, there is little difference of characteristic values between the test results of 182 days and those of 365 days, and the test term of 182 days was shown as the safe side for the estimation of durability.

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 This study deals with air-permeability of finished cover concrete and its relation to carbonation progress of concrete. Recently, there is a trend to evaluate the carbonation rate of concrete by air permeability test in Japan. However most of reinforced concrete members are covered with finishing materials. It is difficult to evaluate carbonation rate of finished concrete only by air permeability of concrete itself. Hence, authors adopted Torrent permeability double chamber tester to evaluate the air permeability of both finishing material and concrete
 In chapter 2, test specimens of exposed concrete and finished concrete were prepared to verify evaluation area of Torrent permeability double chamber tester measuring inner pressure distribution of concrete. It was found that the air pressure of concrete was strongly affected by the quality of finishing materials.
 In chapter 3, relationship between accelerated carbonation rate and air permeability was verified. Based on the test results, prediction formula to evaluate the concrete carbonation with air permeability resistance and finishing thickness.
 In chapter 4, prediction formula was applied to an existing concrete structures and verification was investigated.

 Following conclusions were obtained throughout the researches.
 1) The inner pressure distribution of concrete was non-linear during the measurements with Torrent permeability double chamber tester.
 2) It was found that air permeability coefficient with torrent method was significantly affected by the quality of finishing materials.
 3) Authors proposed air-permeability resistance considering air permeability of concretes and finishing materials, and thickness of finishing. A good agreement could be obtained between the air-permeability resistance and carbonation rate of concrete. Especially the air-permeability resistance notably well evaluated the carbonation rate of concrete with porous finishing material such as mortar.
 4) The evaluation index of air permeability resistance well evaluated carbonation progress of existing concrete structures. This might provide a good perspective for evaluating carbonation progress based on the air permeability of the concrete in new and existing structures

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 Recently, energy-efficient technologies are employed to buildings in terms of reduction of environmental burdens. Vertical fins on walls of tall building are environmentally-friendly components as sunshade louver. As these components are exposed to outer air, wind loads should be evaluated for wind resistant design of cladding. However, the fluctuating wind pressures or forces acting on vertical fins are generally difficult to predict with accuracy because of the reproducibility in wind tunnel experiments which require geometrically-accurate models and installations of measurement system.
 On the other hand, recent development of techniques on computational fluid dynamics (CFD) has enabled us to simulate the complicated flow such as the wind around buildings. Large Eddy Simulation (LES) is expected to be adopted as an effective tool to evaluate wind load for wind-resistant design of buildings. As numerical computations can overcome the difficulties of experimental prediction for complicated models of cladding and components, wind loads of vertical fins are thought to be evaluated accurately by LES. For numerical prediction of pressure fields around vertical fins by LES, unstructured grid systems are effective in terms of flexibility in generating the computational model. Present authors previously discussed the applicability of unstructured LES for prediction of the fluctuating wind pressures on building models (isolated square cylinder, two square cylinders and actual building model in a real urban district) by comparison with experiments.
 In this paper, the fluctuating wind forces acting on the vertical fins on walls of tall building are examined using unstructured LES. Especially, focusing on the size effects of fins, the pressure fluctuations and the flow fields are studied to evaluate wind loads for practical wind resistant design.
 First, the applicability of unstructured LES for wind force estimation of fins is validated by comparison with wind tunnel experiments. Here, the computation is carried out using the same geometry as the experimental model which has relatively larger fins than actual situation. Strong wind forces act on the fins placed at the corners of building and the computed force distributions coincide with experiments with accuracy.
 Next, the wind forces acting on the downscaled fins are computed to simulate the real situation. The flow fields and the wind force fluctuations are quite different from those of experimental (large-scaled fin) model. For the case of downscaled fins, the pressure fields around fins are dominantly influenced by the turbulence structures formed by the building scale. The scale effects on the wind load evaluation of cladding components, which can be examined by only numerical simulations, is clarified.
 Moreover, some cases for practical investigation are also computed (corner geometry and wind direction). As the overall trend, the maximum forces of fins at lower height become larger than other heights. In order to elucidate these phenomena, flow fields at the upwind region are visualized. The vertical flow promoted by the configuration of fins intensifies the horseshoe vortex in upwind region and the secondary vortex appears near the upwind wall on the ground level.
 As a conclusion of this study, for evaluation of design wind load of cladding components such as vertical fins, the scale effects should be considered for accurate prediction of pressure fluctuation. Unstructured LES is available to evaluate the wind loads of vertical fins on walls of buildings and effective to elucidate the flow mechanism on the complicated surfaces of buildings.

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 The authors have been carrying out numerical studies on the effect of a passive nonlinear absorber system containing a strongly nonlinear stiffness and a large virtual mass (NLVM). In this paper, the performance of this proposed absorber system when used for a base isolated building against harmonic ground motion and impulsive excitation is presented. The NLVM system has the following characteristics.
 (1) A large virtual mass ratio reduces response acceleration.
 (2) A strongly nonlinear stiffness avoids a resonance phenomenon and reduces response displacement.
 We have studied STD, LVM, NLVM, TMD and TMD-VM systems ( shown in Fig. 2 ). The NLVM system is a nonlinear system and the others are linear systems. In order to examine the performance of the NLVM system, the shooting method and the numerical continuation technique are used to examine the resonance curves and also to determine their stability while direct time integration is used to examine the transient behavior of the dynamic system.
 Firstly, we compared the NLVM system with the STD and LVM systems. As the NLVM has strongly nonlinear stiffness, it makes the peak of the main resonance curve lean in the direction of higher frequencies ( shown in Fig. 3(b) ). Although several stable solutions occur at the same frequencies, we can use the lowest stable solution in the case where initial conditions are zero or small. Therefore, we regard point Z ( shown in Fig. 3(b) ) as the prediction indicator of a maximum amplitude ratio. Even if the initial conditions are large, the probability of converge to the upper periodic solution is reduced while the amplitude ratio becomes large. The NLVM system is shown not to require a large amount of damping even for a large mass ratio. In the case of a sweep excitation, we can neglect resonance phenomena, because it is extremely difficult to generate a resonance phenomenon along the upper periodic solution during a sweep excitation. In the case of a impulsive excitation, the LVM system can reduce the acceleration amplitude ratio drastically. Since the NLVM system is based on LVM, the maximum value of the acceleration amplitude ratio is of the same level with STD( h₁ = 20% ). However, both NLVM and LVM systems have a lower limit near the R_acc = μ₁/(1+μ₁). For this reason, an extremely large mass ratio is not recommend.
 Secondly, we compared the NLVM system with the TMD and TMD-VM systems. Both TMD and TMD-VM are linear systems optimized using the Fixed-point theory. The TMD-VM is equivalent to the TMD except that the additional mass is a virtual mass. The TMD-VM system is more effective than the TMD system at any mass ratio. In the case of a impulsive excitation, the amplitude ratio of NLVM system is of the same level with TMD-VM, whose mass ratio is in the range of μ = 0.5 ∼ 1.0. In this case, the NLVM doesnot have an additional damping while the TMD-VM requires a large amount of damping( h_0,opt = 12 ∼ 22% ).
 In conclusion, the newly proposed NLVM system can avoid a resonance phenomenon and reduce structural response quite effectively.

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 In this study, we examined an evaluation method of the vertical component of S-waves part in sedimentary layers. In the study of Kyuke et al.(2010), we have proposed an evaluation method of vertical motion by simultaneous incidence of P-wave and SV-wave, using vertical array records. However, there was a problem that the simulation results couldn't explain the observed records in certain frequency range.
 First, in order to improve the simulation accuracy, we focused on the estimation method of the incident wave. In the study of Kyuke et al.(2010), the incident wave inferred only from the deepest sensor's records of vertical array. In this study, we introduced a new technique that estimates the incident wave using all of the vertical array records.
 Then, we simulated the records at an observation point where vertical array observation down to the seismic basement has been conducted at 6 depths. As to the transfer function and response spectrum, simulation results of vertical component were shown to be better consistent with the observed value than the results of SV-wave oblique incidence or P-wave vertical incidence.
 Next, we examined the ratio of P incident wave to S incident wave. It has been shown that the average ratio of the six records was distributed between 0.4 and 2.0 in the frequency range of 0.1Hz to 20Hz.
 Furthermore, in order to confirm the validity of this method, we examined the inferred incident wave. Using the incident waves at the above station, we simulated the records of nearby site. The calculated waves have well explained the observed records of both of the vertical component and the radial component.

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 To reduce building damage due to earthquakes, base-isolation systems have been installed to many buildings in Japan. Rubber bearings efficiently convert the seismic input to large displacement, so clearance is necessary between the building and the retaining wall. Recently, long-period ground motions have been observed, and there are concerns about base-isolated buildings being shaken horizontally more than expected, especially after the 2011 Off the Pacific Coast of Tohoku earthquake. If the displacement is larger than the design, the building may collide with the retaining wall. After the collision, we may have severe acceleration due to the collision impact so it is necessary to control the horizontal displacement of buildings within the designed clearance. In this study, we propose a device to control the displacement of base-isolated buildings as a fault-tolerant system.
 In order to control the horizontal displacement, we focus on the law of energy conservation. When something moves, the equation “Ka+Ua=Kb+Ub” holds for two different states, a and b. Here K means kinetic energy and U means potential energy, respectively. From this relationship, we can find that if we can make Ub larger, Kb will become less. If a building is shaking horizontally, the horizontal kinetic energy that the building has will be reduced as the building uplifts and then the shear deformation that the rubber bearings need to absorb will become lessened. To make Ub larger, we use a device with a shape of a prolate spheroid (like a rugby ball) and make it roll when the horizontal displacement becomes larger than the predefined threshold. In order to make the device free from the whole structure during the normal state, we make a small dent on the top of the device and we make a cavity on the bottom to fit with the notch on the surface to put the device on. The device is designed to work as follows:
 (a) When the shaking is small and under the expected displacement, the system does not have any effect to the base-isolation system.
 (b) In the case of a huge earthquake and the building is subjected to large shaking exceeding the limit of the clearance, the building will touch the device and the device will start rolling.
 (c) While the device rolls, it pushes up the building and converts the horizontal displacement to the vertical displacement. Then the weight of the building will work as restoring force, and finally the device returns to the initial position. These movement will work as a fault-tolerant system.
 We used steel frames and rubber bearings to model as a base-isolated building. The specimen has two layers with rubber bearings to make it possible to get a large relative displacement and we put our device for the fault-tolerant system to push up the upper frame. We did static and dynamic tests using the shaking-table to check the ability of this system.
 By using the shaking-table test data, we found that the second frame was lifted up as designed. Comparing two cases with and without our system, we found that our system worked as a fault-tolerant system and decrease the second-frame's horizontal displacement. We succeeded in decreasing the horizontal displacement with a rolling system and its working efficiency was around 50-60%. When the building started pushing the device, vertical acceleration was observed. Improvements that we have to further investigate would be to decrease the vertical acceleration in the building when it touches the ball and to increase the efficiency of this system. The latter could be achieved by using a mechanism to prevent friction loss between the surfaces of the device and the building.

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 This paper describes an evaluation method for the residual deformation of high-rise reinforced concrete structures by considering the P-δ effect. The method is based on the hysteretic characteristics of reinforced concrete structures, and its effectiveness is assessed using single degree-of-freedom (SDOF) systems.
 Chapter 2 shows that the evaluation method of residual deformation in consideration about the P-δ effect. Reinforced concrete structures have distinctive hysteretic characteristics that depend on the maximum deformation, and therefore, the cumulative plastic deformation is equal to the maximum plastic deformation. As the above result, the residual deformation, which does not include the P-δ effect, can be deal with the average of the maximum positive and negative deformations, according to Eq. (1-b). When the P-δ effect is considered, the residual deformation becomes large to the maximum deformation side, because the central axis of vibration tends to deviate in one direction under the influence of the P-δ effect. This feature suggests that the residual deformation including the P-δ effect can be evaluated by multiplying a ratio of the maximum deformation of the positive and the negative side, according to Eq. (4). As described above, the maximum residual deformation can be evaluated using the maximum plastic deformation, as shown by Eq. (5-b).
 Chapters 3 and 4 describe the seismic response analyses conducted using six SDOF models; in these analyses, the stability coefficient θ was varied. The influence of the P-δ effect is assessed by the stability coefficient θ, and viewing the results by the value of the stability coefficients. These analyses yielded two findings. One was the accuracy of the above mentioned equations, and the other, interesting seismic behaviors.
 With regard to the first finding, owing to the hysteretic characteristics of reinforced concrete structures, the relationship between the analysis results and the results estimated by Eq. (4) showed dispersion. However the values estimated using Eq. (4), were in good agreement with the analysis results compared to those obtained using Eq. (2-b). With regard to the second finding, it was observed that the residual deformation increased by the response in small amplitude after the maximum deformation. These behaviors do not depend on the variation in the stability coefficient θ. Based on the interpretation of the hysteretic characteristics of reinforced concrete structures, the maximum residual deformation can be approximated as the deformation at the maximum plastic deformation. Thus, we proposed that the residual deformation of high-rise reinforced concrete structures, including the P-δ effect, could be evaluated by considering the unloaded deformation of the maximum response values.

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 The oil damper is a typical example of an all-round structural control device that can cover a wide range of vibration amplitudes from small amplitudes caused by wind disturbances to large amplitudes caused by strong earthquakes. It is well known that the mechanical characteristics of an oil damper installed in a building with a bracing frame is expressed by a Maxwell model, and the energy dissipation capacity or the control effect is limited by the stiffness of the spring element in the model. Because oil dampers can be easily converted to variable type dampers that can control the damping coefficient by solenoid valves, there have been a lot of studies on them since the 1990's. We have carefully studied what can be done by controlling the damping coefficient of the Maxwell model, and came to the conclusion that selecting the maximum or the minimum damping coefficient, or the On/Off switching algorithm, was a sufficient strategy when focusing on the energy dissipation efficiency. We also clarified that a damper controlled by the On/Off switching algorithm can dissipate twice as much vibration energy as a conventional oil damper. Based on our study, we developed a variable oil damper with the On/Off switching algorithm in 2000, and it has been installed in more than 30 high-rise buildings in the subsequent 15 years in Japan. Its excellent control performance beyond that of conventional oil dampers has been verified through vibration tests or observation records.
 This paper discusses the possibility of enlarging the energy dissipation capacity of the existing On/Off switching oil damper by introducing an energy recovery system. The proposed device is equipped with an auxiliary oil tank outside of the main cylinder, and the oil flow between the cylinder and the tank can be controlled by control valves. Though conventional oil dampers, including the existing On/Off switching damper, always change all the vibration energy to heat, the proposed device recovers the vibration energy in the auxiliary tank as oil strain energy and reuses it at an optimum timing to enlarge the damper's stroke and thus improves the control efficiency. Its mechanical model is expressed as a four-element model that consists of a Maxwell and a Voigt model in series, and the damping coefficients in the model are switched to the maximum or the minimum based on the states of the control valves. The spring element of the additional Voigt model, which represents the equivalent stiffness of the oil in the auxiliary tank, plays an important role in the model. The change of the mechanical model from the Maxwell to the four-element is the key that enables us to achieve higher efficiency, which can be never realized by controlling the damping coefficient of the Maxwell model.
 This paper first presents a basic configuration of the device, and shows how the energy recovery system works according to the control algorithm. Then the control efficiency is evaluated quantitatively based on the four-element model. The control effectiveness for harmonic excitations or earthquakes are examined through a theoretical approach and numerical response analyses, and it is clarified that the energy dissipation capacity or the ability of damping augmentation of the proposed device can be enlarged to four times that of the conventional oil damper for harmonic excitations, and three times for non-stationary earthquake disturbances. It is also pointed out that the control effect of the proposed device can be considered to be the same effect as that of an optimum tuned conventional oil damper with several times larger stiffness. The enhancement effect of the stiffness and tuning-free nature are typical features of the proposed algorithm.

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 In case of slender buildings and/or tower-like structures, large overturning moment induced by seismic force and/or wind force exerts large cyclic vertical loading on piles supporting these structures. Screw piles are known as an effective means in these cases, and have been used in many projects. These screw piles can be classified into two types of steel pipe piles either with a spiral blade attached near the tip or with spiral wings fixed around a pipe shaft. Although several studies on the behavior of the former piles under cyclic loading have been made, few studies for the latter piles have been made so far.

 In order to evaluate the bearing capacity and pull-out resistance of steel piles with spiral wings fixed around a pipe shaft, each of a spiral pile (a pile with spiral wings) and a straight pile (a pile without spiral wings) in a sand tank was tested under monotonic compressive and tensile loading, as well as cyclic compressive, tensile, and reversal loading conditions. The pile models were made of steel pipes having diameter D_p of 48.6mm and closed end, and consisted of double-tubes, enabling us to measure skin and point bearing capacities independently. The sand tank was cylindrical in shape, having diameter and height 1,200mm each. Sand was pluviated into the tank and compacted using a vibrator, and then subjected to vertical and horizontal pressures of 10kPa and 5kPa, respectively, through membranes. After screwing the pile into the model soil, the vertical and horizontal pressures were increased to 100kPa and 50kPa, respectively, to simulate the stresses at depths of about 10m. The stepwise load increment used in the cyclic loading tests was 1/6 of either the ultimate bearing capacity or the pull-out resistance obtained from the monotonic loading tests.

 Test results and discussions have led to the following conclusions: (1) Under monotonic loading conditions, the bearing capacity and pull-out resistance of the spiral piles were larger than those of the straight piles by more than the diameter ratio between the two, D_w/D_p (D_w=Wing diameter); (2), The bearing capacity and pull-out resistance of piles in cyclic compressive and tensile loadings were the same as those in monotonic compressive and tensile loadings; (3) The bearing capacity and pull-out resistance of piles in cyclic reversal loading, in contrast, were approximately 0.6 times as large as those in monotonic loading; (4) The decrease in the axial force at the head of spiral piles in cyclic reversal loading was induced by the decrease in the shaft friction, whereas the wing resistance and the tip resistance in the pushing direction did not decrease with increasing number of cyclic loading; (5) The decrease in the axial force at the head of straight piles in cyclic reversal loading was induced by the decrease either in the pile tip resistance in the pushing direction or in the shaft friction in the pulling direction; and (6) The decrease in bearing capacity and pull-out resistance in cyclic reversal loading was probably due to soil disturbance and loosening around the pile.

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 The TMD (Tuned Mass Damper) is a passive type control device that absorbs oscillation energy of structures as kinetic energy of a weight of the TMD and disperses kinetic energy by damping of a damper of the TMD. However, we recognize that the performance of the TMD in suppressing seismic responses is relatively limited compared to harmonic responses. The reason is that there is some delay before the TMD become fully effective because they are initially at rest.
 Thus, to effectively control transient response, especially impulsive seismic responses, we propose TMDs with initial displacement, that is to say, dampers whose springs are stretched until the release timing.
 In our previous study, we focused on the considerably high modal damping ratio of the second mode compared to the first mode based on the relationship between the TMD damping ratio and the modal damping ratio of a two-degrees-of-freedom model. And we proposed the design formulas about the TMD tuning and damping ratios and the TMD initial displacement for high control performance under impulse loading. The proposed design formulas are based on the principle that by giving the specific TMD initial displacement under the specific structural initial condition the structural response of the first mode with low modal damping can be eliminated and only the structural response of the second mode with high modal damping is oscillated. But the physical meaning of the design formula about the TMD initial displacement used in this study is not clear because it is an approximate solution obtained by the perturbation method.
 Then, in the next study, we introduced a formula for initial conditions to release TMD initial displacement by applying the theoretical free vibration solution and showed its physical meaning clearly. We studied about TMD initial displacement and structural conditions to release initial displacement by using the complex plane, and we saw that the initial structural condition to oscillate only the second mode was a neighborhood of x●₀ ≠ 0, x₀ = 0 . But by dividing one TMD into plural TMDs that have different natural frequencies, we proved that initial structural conditions to release initial displacement could be changed.
 In this paper, we describe the vibration test using an arch model under impulse loading to verify the control performance of the proposed method experimentally. From test results, we can see that a TMD with initial displacement model show the high control performance for early impulse responses and is most effective in a neighborhood of the TMD initial displacement to oscillate only the second mode using a converted two-degrees-of-freedom model. On the other hand, we can see that the control performance of TMD is very sensitive to the length and the release time of initial displacement. Then, we study the influence of different conditions about the length and the release time of initial displacement on the control performance using a basic two-degrees-of-freedom model analytically.

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 Characteristic of partial compression perpendicular to the grain is known as having a high ductility comparing with compression parallel to the grain, bending and tension. Experimental and theoretical studies have been carried out to evaluate strength and stiffness and consider the structural design. The current strength value is derived from the experimental study. It is difficult to define the strength directly in the compression perpendicular to the grain due to hardening in the final stage of compression test. The strength is defined as the 1.5 time of yield strength of the tests. As the results of the behavior of normal partial compression, confirmation to the partial compression can be ignored in the in the allowable stress design for wooden house. But we don't have enough data for them in the severe compression and when displacement is given to the specimen until 20mm in the condition of standard testing method, the strength of 1.5 times of yield strength is not always obtain from the test. To avoid the damage during moderate earthquake, the limit of strength is also required.
 In this study, many partial compression tests under large deformation were conducted to grasp the damage and safety limit and to evaluate the strength value. The specimen consists of full surface, edge part and center part compression of the sill with/without column and so on. The shaking table tests were also conducted to confirm the damage and safety limit. Results of these static and dynamic loading tests are summarized as follows;
 
 1) The strength obtained from all material tests is satisfied with the strength value in accordance with Japanese Building Standard Law, but the strength in a few of full surface compression dropped the load after the given deformation of 60mm.
 2) Safety capacity for supporting vertical load is confirmed under more than strength value in the shaking test. Safety limit deformation is proposed around 20mm and it is 1.16-1.82 time of timber and 1.40 to 2.34 times of glulam in the current strength.

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 The purpose of this paper is to appropriately judge the decision method for exponents of verification formula for combined stress in the safety side. The decision method allows it to determine by showing the evaluation standard that derived by mechanical model.
 Relation between each stress and aspect pressure is given by Eq.(2), when bending moment, shear force, and axial force is given at the bending moment resisting joint by drift-pin joint.
 P_M = M⁄j …(2a)  P_Q = Q⁄2 …(2b)  P_N = N⁄2 …(2c)
 Since the directions of bending moment and aspect pressure by axial force are the same direction, it becomes Eq.(3a), and Eq.(6) may be obtained by substituting Eq.(2a) and Eq.(2c) for Eq.(3a) and Eq.(5).
 P₀ = P_M + P_N …(3a)
 P_y0 = P_M + P_N …(5)
 P_M⁄P_y0 + P_N⁄P_y0 = M⁄M₀ + N⁄N₀ = 1 …(6)
 Therefore, the exponent shall be m=1 in verification formula for combined stress.
 On the ather hand, due to aspect pressure acts on orthogonality force is given in Eq.(8) for the combined stress by bending moment and shear force. Sine the strength of the drift-pin at any angle is represented by Hankinson's formula (Eq.(7)), the condition which combined stress becomes a yield strength or ultimate strength is when it is to be Eq.(9). Therefore, the verification formula for combined stress by bending moment and shear force is effected by strength at any angle shown by Hankinson's formula.
 P_MQ = √(P_M² + P_Q²) …(8)
 P_yθ = (P_y0·P_y90)⁄(P_y0·sinⁿθ + P_y90·cosⁿθ)   Generally n = 2 …(7)
 P_MQ = P_yθ   tanθ = P_Q⁄P_M } …(9)
 Moreover, combined stress by bending moment and shear force has big effect on secondary moment of disposition of the drift-pin, and depends on the layouts of the drift-pin, the exponent m=2 may become hazard side. However, by using relation between secondary moment of disposition obtained in a numerical analysis and the exponent shown in Eq.(18), It becomes evaluable in the safety side.
 m = 0.12×((I_x·P₉₀)⁄(I_y·P₀))² - 0.47×((I_x·P₉₀)⁄(I_y·P₀)) + 2.00 …(18)
 (M⁄M₀)^m + (Q⁄Q₀)^m ≤ 1 …(20)
 For the combined stress of bending moment-axial force-shear force, it becomes combination as the above. Since the directions of bending moment and aspect pressure by axial force are the same direction, the exponent of verification formula for combined stress is to be m=1. Since aspect pressure by shear force acts on orthogonal to resultant force of bending moment and axial force, the exponent of verification formula for combined stress to be m=2. Eq.(21) is shown in verification formula for combined stress using these numbers.
 {(M⁄M₀) + (N⁄N₀)}^m + (Q⁄Q₀)^m ≤ 1 …(21)

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 The feasible seismic performance of most of existing buildings in Japan is uncertain because the current seismic code does not specify the performance, itself.
 This paper conducted earthquake response analysis of low-rise, mid-rise, and high-rise reinforced concrete buildings designed by Lateral Load Carrying Capacity considering the precise site amplification effect. The total number of site analyzed was 118 in Metropolitan area.
 The paper also discussed the seismic performance of buildings systematically from the viewpoint of site class, structural characteristic factor, height of buildings, etc... based on the analytical results.
 The major findings obtained in this paper were as follows
 1) In the case structural characteristics factor was the same, the maximum drift angle at the site of site classes 2 and 3 showed a significant difference for each site. The difference was especially significant in the low-rise buildings. Site amplification characteristics of the vibration characteristic coefficient in site class 2 and 3 almost did not match to those of the actual sites. Particularly, Site amplification characteristics of low-rise buildings did not. On the other hand, the maximum drift angle of most of the buildings in site class 1 showed little difference in every site.
 2) Except for the sites with extremely long predominant period, the maximum drift angle of mid-rise and high-rise buildings were hardly affected by the structural characteristic factor. On the other hand, the response of low-rise buildings were significantly affected by the structural characteristic factor.
 3) Compared to the buildings designed by Ds=0.3 with limit drift angle of 1/30, the buildings designed by Ds=0.45 with limit drift angle of 1/120 exceeded the limit drift angle in many sites.
 4) The sites generating large maximum drift angle in metropolitan area located along the Tokyo Bay (analysis site name, Kawasaki, Yokohama, Urayasu, Chiba, Anesaki, Kisarazu, and Kyonan), the eastern area of Saitama (Kuki, Kasukabe, Omiya, and Kawaguchi), and the eastern coastal areas of Chiba (Misaki and Kamogawa). On the other hand, the sites generating small maximum drift angle generally located in Tochigi, Gunma, Ibaraki.

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 Braced frame structures are used for school gymnasiums and factories with large space. These are very important buildings which will be used as emergency public shelters in time of disaster. In braced frames, generally the columns are placed along their weak axis for wide-flange steel cross sections and the beam web is connected through gusset plates on the column web by using high strength bolts. These beam-to-column connections are assumed as a pin connection at the stage of seismic design, and seismic performance of the braced frames depend on the strength of the brace. Connection of these components is made based on general design practice although its shape is very complex. In other words, the effect of various differences in connection details on the seismic performance of the braced frame is unclear at the stage of seismic design.
 This paper focuses on differences in connection details, and describes their effects on structural behaviors of braced frame structures. The cyclic loading tests of 2 story-1 bay full-scale braced frames with various connections were carried out. The main parameters are: presence of gusset plate at intersection of braces, details at beam-end connection, and a connection eccentricity of brace. Gusset plate at intersection of braces is prepared to investigate the effect on strength of compression brace. Details at beam-end connection are adopted for the purpose of verifying the influence on the seismic performance of braced frames. Connection eccentricity of brace is selected in order to investigate the additional stress on the framing components.
 The test results can be summarized as follows: (1) presence of gusset plate at intersection of braces results in decrease in effective length of buckling; (2) connection detail with wide pitch or large diameter of bolts caused larger lateral force of beam-column subassemblies; (3) connection eccentricity of brace led to decrease in maximum strength and elastic stiffness of the braced frame.

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 Composite beam in a frame subjected to story drift consists of two portions of positive and negative bending moments, respectively. The lengths and moment magnitudes of the two portions are different due to the composite action and increased bending stiffness caused by positive bending. Thus, in order to understand the composite beam behavior, it is necessary to consider interaction between the two portions. This paper, therefore, proposes a practical analysis method to simulate in detail the behavior of a steel beam, a concrete slab, and stud connectors, and uses it to clarify the interaction as well as the composite action of the beam in double curvature bending.
 Two types of composite beam models are used. One consists of multi-spring element, truss element, and beam element. Another is a FEM model that simulates nonlinear behavior of both steel and concrete. Both models simulate slip between the concrete slab and steel beam, bending of stud connectors, compression and tension failure of concrete slab, contact and separation between the slab and beam end, and yielding of the steel beam. Analysis results are compared with the past test result of composite beam subjected to double curvature. Two analysis models reproduced initial stiffness, strength, and moment-rotation curves of the test result with excellent accuracy (Fig. 11 and Table 7). The analyses also gave more insight into the complex behavior of the composite beam subjected to the double curvature bending of various magnitudes, which are discussed below:
 The steel beam of beam ends subjected to the same rotation, the beam end under positive bending and that under negative bending yielded almost at the same time (Fig. 15). Shear force of a stud connector in a beam portion of positive bending grow larger when the steel beam yields there. On the other hand, it decreased when the concrete slab crashes there. The yield zone of the steel beam was concentrated into the bottom flange the case of positive bending, and it was over all the cross section in the case of negative bending (Fig 18). From elastic loading to inelastic loading exhibiting the beam rotation θ=0.02, bottom flange strains at both ends of the beam were about equal (Fig 19).
 In case of composite beam subjected to double curvature, a ratio of bottom flange strains of the two beam ends under positive and negative bending, respectively, appears to be proportional to inverse of the ratio of moment inertia, the ratio of neutral axis distance from the bottom flange, and a ratio of portion length (Eqs. 5b). From elastic loading to inelastic loading exhibiting the beam rotation θ=0.02, the bottom flange strain ratio is about 1.0, which agrees with the analysis result. This cause is because the beam deflects relatively less under positive bending, and beam curvature grows in negative moment.
 The effect of rotational restraint provided by the columns at the both ends of the beam is examined. Because the restraint is larger at the exterior column where only one beam is connected, the bottom flange strain tends larger.
 However, at θ=0.02 and larger, curvature increase of the end under negative bending is remarkably large, which limits strain of the positive bending side. The exterior column case mentioned above as well as a single span case show that bottom flange strain of the beam in positive bending and thus composite action tends to be smaller than in negative bending.

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 A perfobond strip is a shear connector comprising a flat steel plate with a number of holes punched through it. Concrete flows through the holes forming dowels that act as shear keys, providing resistance in both vertical and horizontal directions. The perfobond strip is the shear connector proposed by Leonhardt in Germany, and the composite effect of steel and concrete is very high due to the shearing resistance of the concrete in the holes. In addition, the perfobond strip shear connector is recognized as having high fatigue strength. It is widely used as a validated shear connector in various steel-concrete hybrid civil engineering structures, since its shearing resistance and fatigue strength are larger and its constructability is better than those of other types of shear connectors such as headed stud shear connectors. Strength evaluation formulas for the design of these shear connectors have been proposed by various investigators around the world. A design formula was specified in the JSCE (Japan Society of Civil Engineers) Standard Specification for Hybrid Structures in 2009. In view of the excellent features of the perfobond strip, these shear connectors are expected to be increasingly applied to connections in building structures. However, connections in building structures are much smaller than those in civil engineering structures, so there is a need for a strength formula that accurately evaluates the force transfer mechanism, such as the restriction stress of the perfobond strip shear connections.
 This paper proposes a new formulation for ultimate shear strength considering the restriction stress of concrete in the perfobond strip shear connections. The formulation provides ultimate shear strength by multiplying shear cracking strength by the ratio of ultimate shear strength to shear cracking strength. In the investigation, a regression formula for the relationship between the ratio and restriction stress is proposed based on a database including previous test results using no-cover simple-specimen loaded restriction force. This paper proposes a method of transforming the effect of restraining concrete around the steel plate hole by reinforced concrete cover and penetrating rebar, and transforming it into restriction stress in the ultimate shear strength formulation. Predictions from the proposed formulation almost agree with test results.

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 From considering in the lessons of the eastern Japan great earthquake, it's necessary to propose rational load estimation method to a tsunami-resistant design of a building in a coastal region. It is important that the development of a practical estimation method of the collision force by tsunami drifting objects on a building in a coastal region.
 Therefore, the objective of present paper is to establish a unified numerical system using MPS method which can solve a series of the phenomenon from the occurrence of tsunami drifting objects until collision with the structures.
  In the present paper, the problems of the rational and practical simulation using the MPS method in collision problem between the structure and the tsunami drifting objects are solved by the imaginary elastic boundary.
  The validity of MPS method with imaginary elastic boundary in the case of applying to the collision problem is clarified by the numerical and tank experiments.

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