Carbonation resistance of concrete is closely related to its air permeability. Rapid air permeability testing method proposed by the authors was applied to predict the carbonation resistance of concrete in structures. Concrete specimens with variable water-cement ratio, type of cement and age of drying were prepared and subjected to the rapid air permeation speed test and accelerated carbonation test. The relationship between two test results was obtained. Next, the carbonation depths corresponding to the design service life class of JASS5 was estimated according to the Draft recommendations and comments for the highly durable concrete structure design and constructions. Finally, rapid air permeation speed corresponding to the JASS5 design service life classes were obtained using the relationships between accelerated carbonation depth and rapid air permeation speed by cement type.

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 This paper presents an analytical hysteresis model of horizontal force-deformation relationship for lead dampers to evaluate the safety of seismic isolation system exposed to long-period earthquake motion. Dynamic loading tests with full-scale dampers were conducted. Yielding strength of damper declined with increase in accumulative deformation, however, it showed rise up temporarily when deformation amplitude was changed on sinusoidal horizontal loading. The analytical model can consider these features. Horizontal load of the test given response displacement motions at isolation layer obtained by a seismic time-history analysis using long-period earthquake motion was in good agreement with one calculated from the model.

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 A substructure-based local damage detection method has been applied to forced vibration test of a real 5 story RC building which has artificially damaged structural members. Because the damages were locally applied, its impact to the dynamic characteristics of the whole structural system was very limited. Nonetheless, the proposed method showed its ability of detecting the damage existence and location. The method is originally needed a large number of sensing points, but an iterative usage technique of a set of small number of sensors was tried in this test in order to verify the method practicability.

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 This study aims to clarify the structural performance of two typical Japanese traditional timber joints used in Kenchoji-temple in Kamakura, Japan. The frame consisting of column and penetrating beam is one of the most important structural elements of traditional wooden structures. More often, there is a connecting joint of the beam, which penetrates through the column. Therefore the shape of the joint is hidden inside the column, not visibly apparent. For this reason, we operated X-ray inspection of the column and penetrating beam, on-site. Through this result we were able to estimate the shape of joint. Bending test of the joint was performed on models of the joints. The results of the bending tests of the connecting joints were compared with those without connecting joint inside the column. Consequently, it was possible to understand the difference between the strength of the each joint by the above results.

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 Ductile fracture occurs when the steel beam reaches its ultimate plastic deformation capacity. In order to evaluate the plastic deformation capacity of beam governed by ductile fracture, it is necessary to clarify the plastic strain capacity of the beam-end flange. In this paper, the in-plane beam analysis was conducted to achieve the strain history at the fracture zone. A hysteresis model of the structural steel effective in evaluating material damage was introduced into this analysis. Moreover, loss of beam section due to the weld access holes and the local out-of-plane bending of the tube wall on the RHS column were taken into account to the analytical model. The analytical method was proved by comparing the analytical results to the experimental results from a database. The plastic strain capacity of beam-end flange till ductile fracture was evaluated by studying the analytical flange strain histories.

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 The majority of the previous studies on braced-frame structures have tested isolated braces or simple subassemblages which neglect the influence of the framing components and the gusset-plate connection on the system performance. In this paper, cyclic loading tests of 9 beam-column subassemblages with an angle brace to investigate effects of the differences in connection details on structural behavior of the braced-frame system.
 From the experiments, a decrease in the initial stiffness of the whole frame and the insufficient strength caused by the unexpected failure modes of the connection are obtained. Based on the comparison with the test results, the simplified evaluation models considering effects of the local deformation and plasticity due to the eccentric brace connections are proposed.

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 This research is concerned with the seismic response control system that using sliding bases as friction dampers. The authors propose that frames with sliding bases are more economic and effective than any other seismic design and earthquake-resistant construction. In this paper, at first, we compare predicted values based on past predicting formulae with maximum deformations from earthquake responses of one-story frames with sliding bases. Secondary, we research in a similar analysis of multi-storied frames by using the equivalent single-degree-of-freedom system. The authors express clearly that sliding bases are practicality from this research's result.

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 In this paper, structural characteristics of beam-end connection using various type built-up H-shaped beams are investigated by full-scale loading test. Main parameter is the geometrical and material properties at the bottom of weld access hole due to the fabrication method of built-up H-shaped beam. Test results, the brittle fracture of beam flange occurred in all specimens. The plastic deformation capacity of SBR specimen consisting of the pre-built-up H-shaped beam and the joint panel with a square hollow section is lowest; the capacity is 50% of the required performance. It was caused by lower two factors, the toughness of submerged arc weld metal and the joint efficiency of beam web connected part.

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 Stud-type dampers that are installed in a limited length of beam span are useful for building structures with many openings, but its performance is affected significantly by the deformation of surrounding frames. Proposed in this study is a design procedure for seismic retrofit of steel frames with stud-type hysteretic damper. The maximum strength and minimum required stiffness of the damper are derived to prevent yielding and lateral buckling of the steel beam connected to the damper and to ensure sufficient energy dissipation. Validity of the proposed design procedure and the performance of retrofit strategy are confirmed fromthe test using a single story steel frame with a slitted steel shear wall.

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 The purpose of this paper is to propose the elastic-plastic hysteretic model of laterally unsupported H-shaped steel beams under cyclic loading. We designed the experiment system which can ensure rigorous boundary conditions for lateral-buckling tests of H-shaped steel beams in large deformation regime. Twenty four beam specimens are employed to observe the effect of the moment gradient and slenderness ratio for the hysteretic behavior. Based on the test results, the basic mechanisms of hysteretic behavior of H-shaped steel beams under cyclic loading is clarified, and the elastic-plastic hysteretic model is proposed.

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 Timber elements, which are different from other structural elements, have a characteristic problem in that the load bearing capacity decreases due to self-burning in the case of a fire, and this self-burning may continue after other fuel in the room has been exhausted. Therefore, the structural fire performance of timber elements should be clarified during not only the heating phase, but also the cooling phase. However, in examining the load bearing capacity of timber elements in a fire, few studies have considered the cooling phase. In the present paper, the fire performance of glued, laminated timber beams is discussed based on load-bearing fire tests that take the cooling phase into consideration.

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