Finishing materials which are bonded to wet slabs peel off at a high probability (reference to Photo 1). We are researching to propose the moisture management index of slab surface. In this paper, targeting at resilient floor coverings as a basic stage, the relation among bond strength and water content of slab surface was quantitatively examined. While drying specimens those were modeled on concrete slabs, floor covering materials were adhered on specimens (reference to Fig 1). Then, water content of slab and bond strength of covering were measured.
 Concrete was very generally used one on construction sites, 27 N/mm² in compressive strength and 18 cm in slump value (reference to Table 1). Surface finishing work was typical condition of construction sites, once of wood trowel and twice of steel trowel. Special curing was not done, and specimens were dried in the air naturally (reference to Table 2).
 Water content was measured using a high-frequency capacitance moisture meter (reference to Photo 2). Floor coverings were adhered according to timing that the moisture meter reading becomes 9.0, 7.0, 5.5, 4.5 or 3.5.
 Two kinds of floor coverings were used, a vinyl chloride tile and a vinyl chloride sheet. Bond strength is grasped by ‘tensile strength’ (reference to Photo 3) and ‘90 degrees peel strength’ regulated JIS A 5536 (Adhesives for resilient, textile and laminate floor coverings). The original method of 90 degrees peel strength could not apply to an actual slab, therefore we made ourselves the device that was able to be measured equal bond strength at them (reference to Fig 2).
 Finally, bond strength of coverings and water content of slabs were compared (reference to Fig 4 and 6). Bond strength has decreased by growing of water content. However, at a certain sort of adhesive, bond strength has rather decreased in the very dry specimen. This result suggests the possibility that each adhesive has an optimal value in water content of slab.
 It is also turned out that, even though surface water contents were the same, there was a difference in bond strength by internal water contents. Also there was a difference between two kind of measurement method. They are very important suggestions.
 Moisture meter reading measured immediately before construction of the floor covering is insufficient as the moisture management index. We will have to examine to combine the change speed of the moisture meter reading or some other measurement method of water content with it.
 We also should do a deeper examination about the bond strength. To set the adaptable method of evaluating bond strength, several physical properties by different force application method should be selected and be combined appropriately. From Photo 1, force besides tension which can be measured by ‘tensile strength’ or ‘90 degrees peel strength’ are obviously applied to coverings in some situations. We will have to set measurement method of other physical properties, and examine the relation between their physical properties and actual force of detachment situations.

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 The evaluation of expectation of linear cumulative damage factor based on the ductility factor and cumulative ductility factor is dealt with. In the evaluation of the linear cumulative damage factor, wave number and the probabilistic distribution of peak amplitudes are required. The wave number is evaluated referring to the closed form equation developed by Matsushima (1991). The probabilistic distribution of peak amplitudes is inferred from the displacements of center of oscillation per. cycle. The displacement of center of oscillation is considered to follow the gamma distribution. The expectation of linear cumulative damage factor is given by integral of random variable.

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 The authors have developed a new vibration-controlled system effective for high-rise RC buildings against long period, long duration ground motions which are highly concerned recently. The system has a couple of shear-walls with pins at the bottoms to utilize oil dampers effectively by amplifying its deformation. To demonstrate the effectiveness of the system, it is important to carefully design the damper connections between different materials (steel and concrete). Since the proposed system is complex, experiments are required to evaluate its properties. The objective of this study is to clarify the mechanical property of the connection between a couple of shear-walls and dampers and to construct a simplified analysis model for design.
 First, cyclic loading experiments using three types of T-shape specimens (normal, cracked and reinforced) were conducted for evaluating their stiffness and durability. As the magnitude of loaded force or the number of loadings becomes larger, the stiffness of the connection between a couple of shear-walls and dampers becomes lower due to extension of cracks at the internal corner. However, it keeps high stiffness compared with that of dampers and the residual crack width is small. Under the maximum damper force, the strain of reinforcement bar is lower than the yield strain.
 Secondly, finite element analysis was conducted to simulate the actual behavior. The analysis model is 2-dimensional and elastic plane elements are used to simplify the analysis. In order to take into account the non-linearity caused by cracks, the model is divided into two parts by the presumed crack line and they are connected by 1-dimensional non-liner springs representing the properties of concrete and reinforcement bars. Stiffness decrease is mainly caused by the crack at the internal corner, and it converges due to balance of loaded force and reinforcement bar stress. Since diagonal bars are highly related to the connection stiffness, the increase of diagonal bars improves it effectively.
 Finally, a simplified analysis model of damper connection was proposed to enhance the usability in the usual structural design. To consider the effect of the internal corner crack in more detail, an additional spring is introduced in the form of series type through rigid elements and beam elements. It is easy to adopt because all elements are only composed by beam elements.
 It is concluded that the connection between a couple of shear-walls and dampers has sufficient stiffness and durability against long period, long duration ground motions.

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 The 2011 Great Tohoku Earthquake with Mw 9.0 that occurred off the Pacific coast of Japan was a multi-segment earthquake. Although the earthquake source was from one ruptured point, numerous ground motion patterns were produced because of differences in the orders and time intervals of the occurrences. As such, predicting multi-segment earthquake waves needs sophisticated expertise and great deal of effort. Even if they are accurately predicted, evaluating the response of high-rise buildings to multi-segment earthquakes is complex.
 Now, measures have been carried out to protect high-rise buildings against the long-period ground motions for the Nankai trough multi-segment earthquakes. One widely adopted measure is incorporating dampers in the design of high-rise buildings to reduce seismic responses for long-period ground motions.
 Proposed by previous researchers is a seismic evaluation method for seismic structures subjected to multi-segment earthquakes by considering the single earthquakes constituting them. With a possibility that this type of earthquake will occur in Japanese coastal waters, this current study developed a method for evaluating damped high-rise building subjected to multi-segment earthquakes.
 Chapter 2 of this paper discusses the ground motion of multi-segment earthquake and the earthquakes constituting it. The ground motion of Tokai-Tonankai-Nankai multi-segment earthquake estimated by past researchers is used in this study. This long-period ground motion is simulated using a three-dimensional (3D) subsurface ground model for the Kanto, Nobi and Osaka plains.
 The 50-story steel vibration control building models with dampers used in this study and response evaluation are discussed in Chapter 3. In Chapter 4, the time-history analysis of building models for the multi-segment earthquake and for the single constituting earthquakes are discussed. Results are compared to analyze the maximum response and cumulative damage for multi-segment earthquake.
 Chapter 5 expands the seismic evaluation method of past researchers into the prediction method for damped structures subjected to multi-segment earthquake based on the response from the single constituting earthquakes. The maximum response produced by the multi-segment earthquake can be estimated by increasing the ground motion of the single constituting earthquake to the provisional multi-segment earthquake level based on an adjustment factor before the seismic response analysis. This adjustment factor (as in previous researcher) is the ratio of the greatest single constituting earthquake spectrum to the SRSS spectrum of the single earthquakes. The cumulative damage is estimated by summing up the energy of individual earthquakes and applying the energy balance-based seismic response evaluation method. The results of the seismic response analysis show that these estimation match well the responses produces by multi-segment earthquakes.
 Finally, the method and procedure to predict maximum response and cumulative damage for multi-segment earthquake by single earthquakes are proposed in Chapter 6.

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 Post-buckling behavior is one of the most interesting topics of structural mechanics. In our previous paper³⁰⁾, load-deformation relationship of an elastic bar buckling between two rigid plates (Fig. 1) had been shown by using linear beam theory. In this paper, inspective experiment had been held to confirm our theory. The result of the experiment suggests that our theory is able to explain the phenomenon in loading phase. However, as for unloading phase, more research has to be done on this topic.
 Chapter 1 is the introduction to review the background of our research. As for architecture and civil engineering, buckling-restrained brace (BRB) is one of the examples to apply the evidence of this paper.
 Chapter 2 shows our previous theory³⁰⁾. Using this theory, we can calculate the load-deformation relationship of the bar restrained by two rigid plates (Fig. 2).
 Chapter 3 is the explanation of the test equipment prepared for our research (Fig. 3). This instrument compress the aluminum flat bar by displacement controlled loading. The binary condition of the bar is pinned and the bar is restrained by two rigid plates made of steel which are fixed at both side of it.
 Chapter 4 is the tensile test on aluminum to identify Young's modulus (index E).
 Chapter 5 shows the result of the experiment. The parameters of test pieces are shown by Table 2 and Fig. 5 is the load-deformation diagram. Fig. 6 shows the mode of buckling observed in this experiment.
 Chapter 6 is about the proof of material elasticity, the effect of imperfection and the reproducibility of this experiment.
 Chapter 7 is the conclusion. The important points are following.
 · The load-deformation relationship shown in our previous theory agrees very well with the experiment on loading phase.
 · The reason why our theory do not match the experiment on unloading phase is that the modes of buckling which have been assumed in our theory are different from the actual activity.
 · The load-deformation diagram comes up from this experiment may be affected by the imperfection of the aluminum bar. However, in terms of the transition of buckling mode, this experiment has surely reproducibility.

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 This paper focuses on the elasto - plastic behavior of static and dynamic responses for single layer lattice domes, which are subjected to vertical loads. The purpose is to make clear the relationship between seismic responses and static responses such as static absorbed energy properties after and before yielding, and to estimate bearable seismic levels with the information of static elasto - plastic behaviors. The two responses compared are shown in Fig. 14. The dimensions of both figures are equal in multiplying or dividing by circular frequency.
 The single layer lattice domes are shown in Fig. 1. Half open angle of members and self-weight are adopted as numerical parameters as shown in Table 3. The static elasto - plastic behaviors are shown in Fig. 3. In the figure, The solid lines are the equivalent velocity of strain energies, the dotted and dashed lines are that of static absorbed energies and the dashed lines are that of potential energy performed by the product of self-weight and vertical displacements. These relationships obtained are simplified into bi-linear relationships as shown in Fig. 4 to obtain the static elasto - plastic property coefficient j. The obtained results of coefficient j are shown in Table 4.
 Secondary, the dynamic elasto - plastic behaviors are estimated against 4 seismic waves of Fig. 5. The dynamic behavior obtained is the relationships between maximum ground acceleration PGA and strain energies. The obtained results are shown in Figs. 6-9 and simplified into bi-linear relationships to obtain the dynamic elasto - plastic property coefficient q, as shown in Fig. 14(b). The obtained results are shown in Table 5.
 In comparing the two property coefficients j and q as shown in Fig. 10, BCJ wave is relatively large about the dynamic effect. On the contrary, El Centro wave is the smallest among the four waves. This reason is made clear in considering the input acceleration power history as shown in Fig. 11. BCJ wave of Fig. 11(a) has many peaks during the motions, but El Centro wave of Fig. 11(b) has a few peaks during the first half of motions. These strong characteristics of seismic waves can be considered with the input energy spectrum V_E as shown in Fig. 12. Then the ratios q/j are compared with the ratios V_E/S_V. The ratio q/j decreases as the ratio V_E/S_V increases.
 The Eqn. 5 is the regression formula obtained by the data distributed in the quadrangle of Fig. 13, expressed as dotted and dashed line in the figure. The PGA corresponding to the limit state deformations can be estimated with Eqns. 4 and 5. The predicted results are shown in Fig. 15 and Table 6.
 The following conclusions are obtained in the present study: (1) The relationship of maximum earthquake input acceleration PGA and strain energies of domes shows bi-linear type such as the relationships of static absorbed energies and displacements. (2) In comparing the preceding two relationships as for dynamic and static responses, the change ratios among elastic and plastic ranges are dependent upon the seismic waves. The distribution tendencies are able to be explained with the information of input acceleration power history of seismic waves. (3) The ratios of dynamic property q against static property j becomes smaller, as the ratios of energy spectrum V_E against velocity response spectrum S_V becomes larger. (4) The present estimation method of PGA corresponding to limit state deformations shows a relatively good accuracy.

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 Earthquake damage estimation after a major earthquake is important for prompt rescue. We developed a hysteresis characteristics model for existing wooden houses that can reproduce actual behavior under large displacement for earthquake damage estimation. We conducted the shaking table tests of wooden houses with different strength and input ground motions in order to get experimental results used in the seismic response analyses.
 The types of shear walls and the amount of shear walls varied series were conducted. The specimens of each series were shaken at the same time. The input ground motions were the K-NET Anamizu, the K-NET Hiroo, and the simulated earthquake motion. The K-NET Anamizu recorded in the 2007 Noto-Hanto earthquake has large 1-1.5 sec. responses which have close relationship with heavy damage to wooden houses and buildings. The K-NET Hiroo recorded in the 2003 Tokachi-Oki earthquake is very short period of 0.2 sec dominated motion. The simulated earthquake motion (phase: El-Centro NS) is period of 0.4 sec dominated one, the type of which has never been recorded. The result that the displacement of the specimens increased as the strength decreased was found under the K-NET Anamizu. Buckling of a brace and a damaged nail were seen in the specimens with low strength. The displacement of all specimens were small and they were not damaged under the K-NET Hiroo. The unusual result that the displacement of the specimens increased as the strength increased was found under the simulated earthquake motion in contrast under the K-NET Anamizu. This is because the natural period becomes shorter as the strength increased in wooden houses.
 We tried to reproduce the experimental results by seismic response analyses. We used the modified Takeda-Slip model for wooden houses as a hysteresis model. We modified the hysteresis characteristics model as follows:
 (1) Modification of the formula of unloading stiffness
 (2) Consideration of deterioration under cyclic load
 (3) Consideration of the asymmetrical behavior in the case of plywood We could reproduce the experimental results accurately by the modified model.

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 Main purpose of this study is to investigate residual seismic capacity of damaged buildings. An evaluation method of residual seismic capacity (R) using contribution factors of structural components (Er) was proposed. Er is evaluated by assuming invariable inter-story drift distribution for a building even after damage to focus on the investigation of effect of location of components. Then, modeling methods of damaged buildings were discussed using SDOF models. Finally, it was shown that the proposed method can estimate Rappropriately for buildings with uniform inter-story drift distribution but cannot for buildings with non-uniform distribution through dynamic analyses of prototype frames.

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 In Japan, square steel tubular columns are widely used. When the building is under a seismic action, columns will be subjected to axial force with double curvature bending moment. Therefore, it is important to design the column under these combined loading in the ultimate limit state to guarantee the safety. Recommendation for Limit State Design of Steel Structure (LSD) and Recommendation for the Plastic Design of Steel Structures specify the requirements for column to guarantee sufficient strength and ductility. The plastic deformation capacity of the column that is subjected to compressive axial force with one end monotonic bending moment is ensured more than 3 by LSD. However, deformation capacity of the column that are subjected to compressive axial force with monotonic double curvature bending moment is not shown clearly. Test results that can confirm the appropriateness of LSD requirements for square steel tubular column are limited. It is necessary to gather more data of maximum strength, deformation capacity, and elasto-plastic behavior of square steel tubular columns by testing. Moreover, column that is subjected to compressive axial force is important to take into account second-order effects.
 In this study, testing where axial force with monotonic double curvature bending moment (end bending moment ratio equal to 0.5) are applied to the columns simultaneously are conducted. Maximum bending moment, plastic deformation capacity, and second-order effect that will be caused by Pδ moment were evaluated from the test results. Comparison between LSD requirements and test results were also shown.
 From the test results, followings are found.
 1) Two types of collapse mechanism are confirmed.
 i) Local buckling occurred at one end of the column determined the ultimate state and deformation capacity.
 ii) Pδ moment determined the moment capacity at the loading point; increment of the bending deflection determined the ultimate state. Local buckling was not observed during the testing.
 2) When the value of n_y·λ_c0² is greater than 0.20, second-order effects determined the plastic deformation capacity. Plastic deformation capacity R of the columns that were determined by Pδ moment had a linear relation between n_y·λ_c0². When the value of n_y·λ_c0² is smaller than 0.17, plastic hinge was formed at the end of the column and determined the collapse mechanism. Nominal width-to-thickness ratio equals to 20.8 that was used in the testing had a plastic deformation capacity around 4.0 when it was determined by local buckling collapse.
 3) Plastic deformation capacity greater than 3 were observed even if the current LSD limitation was not satisfied. However, from the point of view of collapse mechanism, LSD limitation can form a plastic hinge at the end of the column which is expected in design.
 4) Even if moment amplification factor calculated by LSD is 1.0, the location of the maximum moment may appear in the middle of the column. i) ii)

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