This paper presents the results of a series of long term survey on carbonation of concrete in structure. Six reinforced concrete model walls, made of conventional concrete with slumps from 12 to 21 cm and flowing concrete with slump of 21 cm fluidized from initial slumps of 8 and 12 cm, and stored in open air were tested for carbonation at 2, 4.5 and 15 years. 25 year survey was conducted only on 2 model walls made of conventional and flowing concrete with slump of 21 cm. The test results indicated that the carbonation was greater for flowing concrete than for conventional concrete. Greater carbonation of flowing concrete can be due to increase in air voids in hardened concrete. Carbonation was found to be accelerated with increase in air voids; indicating 0.5 mm/√<n> increase with 1 % increase in air voids. Carbonation was smaller than the value calculated by C=At^<1/2> and was found to be calculated by C=At^<1/3>. The rate of carbonation correlated closely with 28 day standard-cured cylinder strength. The standard deviation of carbonation increased with time and with carbonation depth, the coefficient of variation was 0.4 regardless of time.

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The ultimate purpose of this study is to establish the method that can estimate the effect of aggregate grading on the fluidity of concrete. Therefore we focused on the size and grading range of aggregate, which are basic elements of grading, and clarified the relationships between them and consistency and rheology constants of mortar and concrete by experiment. By the way, in terms of reduction of drying shrinkage, autogenous shrinkage and hydration heat, it is important to determine the most appropriate grading which yields a given fluidity of concrete and maximum aggregate volume. To achieve this goal, we clarified based on the above experimental results that the aggregate volume ratio in concrete with a given fluidity was described mathematically by the distance of dispersion, solid content, maximum size and grading range of aggregate based on the excess paste theory.

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Using bleeding water gathered by pressurized and filtered of diluted concrete sample with purified water, some methods were suitable to test for chloride concentration in water of fresh concrete with low-water binder ratio and with few bleeding water. As a result, the following conclusions were obtained. 1) In case of high-strength concrete, which W/B is 16% and 18%, using diluted concrete sample by purified water 50cc against fresh concrete 3kg, it is possible to test in about 1 5 minutes for chloride concentration in water of fresh concrete with low-water binder ratio. 2) It is preferable to gather a quantity of filtered water necessary for examine within 4 hours, while the change of density is small. 3) Among the methods by JASS5T-502, Coulometric titration and Mohr's method may have applicability to test for chloride concentration in water of fresh concrete with low water binder ratio, with dilution method. It is possible to examine for chloride concentration in water of fresh concrete with low water binder ratio at the construction site.

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A single-degree-of-freedom bilinear system has a simple similarity relation between the input and output motion; a simultaneous amplification of the input motion, the elastic limit, and the yield force by a certain factor induces an amplification of the response by just the same factor. The purpose of this study is to estimate the energy response characteristics of a bilinear system efficiently by utilizing this similarity relation. The input ground motion is given by a stationary random process with a power spectral density function corresponding to a "pseudo-acceleration" spectral density of an adapted single-degree-of-freedom system under a white noise excitation, The energy response problem for the bilinear system under the stochastic excitation is formulated and simplified by use of the similarity relation. Numerical results clarify the relations between the characteristics of the input ground motion and the non-linear energy response.

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The total energy input into a structure exerted by an earthquake is a very stable amount. Then, it becomes very important to predict the distribution of damage for the seismic design purpose. The damage distribution is influenced by the distribution of the strength and the stiffness ratios of beam to column. In this paper, a basic rule which governs the distribution of damage in weak-beam type multi-story steel structures is derived through elasto-plastic response analysis, and is expressed in a simple formula. Applied analytical model is fishbone-shaped frames. The results of analysis are summarized in a form of the damage concentration index n.

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In this paper, a procedure enabling various solution searches on the genetic algorithms is proposed for the structural morphogenesis. The proposed procedure is able to obtain a solution set including global optimal solution and local optimal solution with high estimation in feasible region. This procedure is applicable to both of the single-objective optimization problem (SOP) and the multi-objective optimization problem (MOP). First of all, our procedure is explained compared with main schemes of past researches. Next, the procedure is applied to maximization problem of bivariate functions corresponding to SOP and a problem of two bivariate functions corresponding to MOP. The effectiveness of the procedure and the fundamental characteristic of the solution are shown from numerical results by their bivariate functions. Finally, this procedure is used for the optimization problem of 2D truss structure and 2D frame structure. A solution set (structural forms) with high estimation and diversity is presented from numerical results in their structural problems. Especially, in the MOP of the frame structure, multiple structural forms with a clear transmission path of loads are able to be obtained.

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Nonlinear soil-structure interaction effects under strong ground motions should be considered in the seismic design. This paper presents the results of cyclic loading test for pile foundation in dry sand to investigate the nonlinear behavior of pile foundation in large displacement range. The experimental parameters are the number of piles, loading rate, relative density of soil and alignment of pile group. The major findings obtained from tests are summarized as follows: l) the soil around piles deformed significantly even at small amplitude, 2) shear force-displacement relationship, resultantly secant stiffness and equivalent damping factor, at pile head shows significant nonlinearity even in very small displacement range, 3) shear force at pile head hold almost constant value after the soil get failed.

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Nonlinear soil-structure interaction effects under strong ground motions should be considered in the seismic design. This paper presents the results of cyclic loading tests for pile foundation in dry sand to investigate the nonlinearity in the pile group effects in large pile-head-displacement region, The major findings obtained from tests are summarized as follows; l) variation in pile group efficiency with increase in pile-head displacement is not large, 2) the shear forces of the front piles are remarkably larger than those of the rear piles, 3) the ratio of the shear force at pile head to the total horizontal load is affected by the yield of piles and the failure of the soil as well as the number of piles, pile location, soil density, and loading direction.

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With regard to restoration of detached house foundation, the relation among inclination angle, distortion angle, and the degree of trouble was analyzed trough the actual condition survey and the settlement tests of full-size houses. Inclination angle related to difficulties on use and function, and distortion angle related to structural difficulties such as cracking need to be clearly distinguished. Though the recognition of inclination angle through the analysis results is just above approx. 4/1000, damages are caused even by a slight distortion angle and are gradually progressed. Each threshold angle (standard) is considered to be 6-8/1000 for inclination and 5/1000 for distortion.

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Traditional timber pagodas in Japan are believed to have high seismic performance, because there is no document of a timber pagoda, which was destroyed by earthquake. In December 2004, shaking table tests of a 1/5 scaled model of a traditional timber five storied pagoda was operated at NIED in Tsukuba. The excitations were operated 77 times on the specimen. The maximum horizontal displacement was 144.9mm (1/33rad.) measured at the top of frame, by the 1995 JMA Kobe NS input motion (maximum acceleration scaled to 2888gal). The vibration characteristics of the structure determined by shaking table tests are discussed in comparison with those by micro tremor measurements. The natural frequency of vibration in the first mode of the structure was found to be in exponential relation with the maximum horizontal displacement.

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The study described in this paper addressed an estimation of the effective width of wood glued stressed -skin panels under out of plane bending. Based on the results of sensitivity analysis of investigating the par ameter effects on the effective width, an estimation formula was derived first. With the aid of experimental inspection, it was indicated that the effective width could be estimated alone by the primary effective width which is given by an exponential func tion of the rib spacing ratio L/S. Using the value of flange effective width determined from so rewritten formula (the approximate formula), calculated results of stresses and deflections of a panel obtained by the transformed -section beam theory coincided satisfactory with the experimental results.

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Response of reinforced concrete wall-frame structures subjected to earthquake motions was investigated by testing a full-scale six-story specimen on the world s largest tri-axial shaking table "E-Defense". The test specimen consisted of three parallel three-bay frames in the longitudinal direction. The span widths were each 5.0 m in the longitudinal and transverse direction. The central frame had a structural wall in the central bay continuous from the 1st to the 6th story. Spandrels were placed above 1st to 6th floor girders in one of the outer frames in the longitudinal direction. The structure was designed based on the code of design and practice in 1970'. All columns and walls were defined as flexural yielding type based on current code calculation. The test specimen was subjected to series of earthquake motions and finally collapsed due to shear failure in short columns and the structural wall at I st story during a strong earthquake motion. The test results were studied with respect to structural performance, collapse process, response story shear, and vertical distribution of lateral forces.

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To develop a simple prediction formula of bond splitting strength, local bond stress versus slippage of reinforcement relationship was proposed in the preceding study (Part 4). This research presents the proposal of predicting equation for bond splitting strength with confinement of lateral reinforcement and the results of analysis performed to investigate influence of structural factors, such as bond length, Iateral reinforcement ratio, concrete strength, Young's modulus of lateral reinforcement. The newly developed prediction formula is expressed for two different types, i.e., concrete splitting mode and lateral confinement mode. The predicted bond splitting strengths show a good agreement with experimental results of previous studies.

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Two types of hinge isolated shear walls (called as HISS RC walls) were proposed and tested by authors. One was fully un-bonded, and the other was partially un-bonded. They showed excellent deformation behavior compared with ordinary shear walls. However, in the large deformation range, they showed slip phenomena which defined deformation capacaity. This paper reports the test results focusing on effects of dowel bars and axial force on restriction of slip phenomena, and discussion of major causes and restriction method of slip phenomena based on test results including past two specimens.

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For developing high tension bolted frictional-slippage damper with much higher friction coefficients than conventional ones, the dynamic loading tests were conducted by using the bolted frictional-slippage connection specimens that sandwiched aluminum alloy sliding plates. In addition, for stabilization of frictional slipping behavior, specimens were also sandwiched by rubber washers. As the results, specimens using aluminum alloy sliding plates and rubber washer showed stable frictional slipping behavior. The results of these tests showed that slip coefficient of more than 0.60 for A1050P aluminum sliding plates and invariable slip coefficient of 0.36 for A2017P were confirmed respectively.

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In wide-flange steel column-to-beam connections, transverse stiffeners are often used to prevent the local failure of columns caused by concentrated beam-flange force. It is well-known that the stiffeners work insufficiently when the beam-flange width is relatively narrow due to the stress concentration to the inner parts of the stiffeners. This paper investigates the influence of beam flange width on the connection strength. The strength formulae of the narrow beam-flange to column connections reinforced with transverse stiffeners are derived by applying the yield line theory. The relationship between the beam-flange width and the strength is examined. The strength reduction is predicted for connections with narrow beam-flanges. Six loading tests and many finite element analyses are performed for the local connection models. The load-displacement relationships and strain distributions on stiffeners and columns are monitored. The results show the validity of the strength prediction and the failure mechanisms used in deriving the strength formulae.

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The strength of an H-section column-to-beam weak axis connection with split-tee stubs is dominated by out-of-plane deformation of web plate of the column, especially when transverse stiffeners are omitted to simplify fabrication process of a beam-to-column connection. The main purpose of the present study is to analytically derive general yield and maximum strengths of the bolted column web-to-split-tee stub connection by yield line analysis, including the case where reinforcing plates or angles are attached at the web. The validity of the analytical strengths of the connection is investigated by comparing with tensile test results of the connections.

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The purpose of this study confirms that the hysteretic behavior of structural member subjected to multi-axial cyclic loads can be predicted based on the uni-axial stress hysteretic model. In addition, it is provided on how to evaluate the hysteretic behavior of short span beam subjected to combined bending and shear force. For this purpose, the shear yield type beams are carried out under the simultaneous shear and bending moment loading. The numerical analysis of steel structural member under multi-axial loads was carried out and the material properties were determined from the simple hysteresis model under uni-axial stress. Comparing between the numerical analysis and test showed that numerical analysis using hysteresis model under uni-axial stress was applicable to predict global and local hysteretic behavior on the steel member. On the basis of numerical analysis results, the damage correlation between member and material could be evaluated.

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Quantitative information on the seismic performance of nonstructural components is scarce. Among various nonstructural components, damage to interior drywall partitions affects significantly to the economic loss. Three full-scale drywall partitions, i.e., a standard plane partition, a partition with a door, and a partition with an orthogonal wall, are tested to observe the initiation and evolution of damage in cyclic loading conditions up to a drift angle of 0.1 rad. The plane drywall partition remains undamaged up to 0.01rad, while the partition with a door or the partition with an orthogonal wall sustained damage at a smaller drift angle because of local constraint. The partitions exhibit some lateral resistance, which is provided primarily by the bearing between the gypsum board and surrounding columns. The progress of damage is presented in terms of the ratio of the repair to initial cost. The ratio reaches about 1.0 and 2.0 for a drift angle of 0.04 rad and 0.06 rad, respectively.

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Our previous papers clarified the flexural buckling load for H-shaped compression members with the eccentric braces, which are located on the center of their length axis. Then, it was assumed that the non-structural members were used as the bracing. On the other hand, if the roof with any flexural stiffness can be jointed directly to the compression members, it is possible to use it as the bracing. In this paper, the flexural buckling behavior with torsion for H-shaped compression members is presented, and the relationship between the buckling load and rotational stiffness of the roof is estimated.

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The damage ratio equation of H-section cantilever beam under strong repeated load is obtained on the basis of the very low cycle fatigue behavior of it. By introducing not only the steel tube crack of concrete filled steel tube column (CFT column) but also the very low cycle fatigue of H-section beam, the collapse analysis method of multi-story CFT frame under extremely strong ground motion has been proposed. Seismic response and collapse of multi-story CFT frames designed under quite different conditions are calculated by the presented numerical analysis method. From the calculated results it is shown that the crack of CFT column is closely related to the collapse of CFT frame but the failure of H-section beam does not effect directly on it.

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Buildings composed of coupled shear walls with damper, CFT column, and flat plate slabs is one of the type of buildings that can be reused after severe earthquakes with low repair cost. To evaluate the vertical load resistance capacity of the newly designed CFT column-flat plate connection, two series of experimental studies for element specimens were carried out. Total of thirty-four specimens are tested and strength capacities of the results were examined using vertical load resistance macro models and showed good agreement. At design, the vertical strength can be evaluated by the ACI and AIJ standards in the safe side.

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Questions are as follows. 1) In the paper, initial and second yield criteria of H-shaped steel flange are assumed to be ±0.2% strain. What are the mechanical senses about the yield criteria assumption. 2) In the paper submitted in April 2005, the paper published in June 2005 is referred. Considerable part of contents is overlapped. What do the authors think about the relationship between the paper of this journal and the referred paper.

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The authors wish to thank Prof. Katsuki Takiguchi for the discussion. The answers to his questions are as follows: (1) The yield judgment on steel of ±0.2%-strain is adopted in order to macroscopically clarify the damage-level of cementitious column base and the plasticity-level of steel column. (2) Additional referred papers are required by reviewers in order to clarify the experimental work and the design approach on the proposed column base. In addition, the clear difference between this paper and the referred paper published in June 2005 is identified.

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