A report has been compiled on the use of blast-furnace slag powder with Ecocement to improve the long-term strength gain. This study discusses the long-term strength gain of Ecocement with blast-furnace slag powder that it examined the influence of the water cementitious material ratio, mixing ratio of the blast furnace slag powder and the curing condition, in order to obtain basic data to clarify the mechanism on the long-term strength gain of Ecocement with blast-furnace slag powder. As a result, it was able to be confirmed that the long-term strength gain of Ecocement with blast-furnace slag powder was improved regardless of the water cementitious material ratio, mixing ratio of the blast furnace slag powder and the curing condition. Results of pore size distribution, Ecocement with blast-furnace slag powder was acknowledged densification of pore volume. This study had a high correlation between a decrease in the pore volume of 0.01μm or more and compressive strength, it was clarified that the long-term strength gain had improved because of a decrease in these pore volume.

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This paper presents the results of experimental studies on the strength characteristics of concrete. Strength development of concrete is influenced by the types of cements and the curing temperature. Therefore, in this research, it is found that the temperature range for temperature compensated specified strength T of JASS 5 is proper, and the time for formwork to remain in place is proposed according to the types of cements. As for Young's modulus, correction factor for the types of cements should be considered to the AIJ expression of it.

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Compressive strength prediction of concrete is essential in cold weather concreting. Maturity method and strength prediction method using logistic curve have been used for cold weather concreting in Japan. This method is limited within the range from water to cement ratio 45% to 65%. In this paper, we propose a strength prediction method for enhancing the range of water to cement ratio. The experimental data in the past was used and analyzed. As a result, the approximation by Gompertz curve showed high accuracy in the strength prediction of the concrete within the wide range of water-cement ratio. We propose the new strength prediction method for applying Gompertz curve.

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The relation between the care period and the strength development of concrete was examined by using the cylinder specimen. The result showed that the strength development of concrete have a correlation with the compressive strength and the rate of the strength appearance at the time when the mold was removed. Therefore, if the target strength and the material age for removing the mold are decided, the rate of strength appearance is obtained by the calculation, which makes possible the estimation and the judgment about attaining necessary concrete strength.

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The water content of crack in the concrete under waterproofing membrane was investigated by water vapor permeability test and simulation analysis. The test specimen has concrete cylinder-shape with crack in the center of their substrate. The permeability tests were carried out with the following parameters: the width of crack in the concrete, the presence or absence of a waterproofing membrane, the type of membrane and the membrane thickness. As a test result, it was clear that water vapor permeability around crack area of concrete substrate was higher than that of no crack area. Then, even if the crack area in the concrete substrate was coated with waterproofing membrane, it was easy to infiltrate water into the crack of concrete. The simulation method to calculate the water permeability at the cracked area of the concrete substrate was proposed based on diffusion theory and water transmission that were obtained by permeability tests. The simulation results and the experiment results of water content in the concrete are furthermore discussed.

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Main purpose of the present study is to propose a failure criterion for the brick structural element under combined stresses of normal and shear. Firstly, a series of experiments was carried out in which experimental factors include the method of shearing test, strength of mortar, angle of joint, and normal stress applied. Failure pattern observed in the most specimens was the interface failure occurred between a brick and jointing mortar, while two failure patterns are possible the interface failure and the jointing mortar failure. Next, based on the experimental data, a simple failure criterion formula was proposed in which both of the two types of failure patters can be considered.

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The development of seismology and recent observation records have been evolving the ground motions to be considered in structural engineering. The future research will seems to require quite an amount of revisions in ground motions. Since it is difficult to envisage the goal of seismology, some measures to deal with increasing levels of ground motions must be included in structural engineering. Consideration of excessive strength in structural engineering is not economical. However, making extra margin in sliding bearings for seismic isolation devices require less expenditures in structural design. The authors have conducted analytical study of this kind of system and have confirmed the sliding isolation system has the potential to keep isolation characteristics for large input ground motion level. However, the maximum displacement and residual displacement become quite large, especially when the elements to provide restoring force are not employed, it was over 1.0m. The authors think this level of displacement can be considered in the structural design of foundations to withstand P-Delta effect by building weight. From this study, the authors concluded that if the foundations are well designed to accept P-Delta moment in isolation interface, sliding bearings can be a potential candidate to provide robustness to deal with excessive level of input ground motions.

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Seismic behavior of pile group is different at the position of piles. It is because of not only the nonlinearity of structure, pile and soil but also axial-force fluctuation and foundation girder stiffness. There is no example of its having examined all factors at the same time though the examination of each factor is done. Authors examined the analytical study on the influence of the nonlinearity of pile, soil and foundation girder for seismic response of pile-supported structure. This report shows the influence of nonlinearity of ground, piles, and foundation girder for the seismic response of a pile-supported structure.

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In this study, new type of precast unbonded post-tensioned exterior beam-column joint of a long span frame was proposed and tested under the simultaneous action of gravity and cyclic load. The connection was designed with shear bracket to resist the shear force induced by the gravity load and post-tensioned steel to resist moment and shear force due to the earthquake load. The design concept is to control the deformation due to the earthquake load by accepting the opening between the beam and column interface in order to keep away from the damage to the beam and the column. The test results showed efficient seismic behaviors with minor cracks occurred in the beam and column, good self-centering behavior and small beam slip.

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Seismic responses of raised lattice domes with substructures are known to be very complicated, and not only horizontal response but also vertical response is excited under horizontal seismic input. Such action causes damage on structures and non-structural elements such as ceiling and lights. A seismic isolation system is known to be effective to reduce such response. In this paper, variations of a simple response evaluation method for lattice domes supported by substructures with a mid-story seismic isolation system are proposed using response amplification factors and linearization techniques. Their validities are discussed against the background of time history analyses.

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Splitting of wood loaded perpendicular to the grain is a critical issu in timber engineering, and the splitting and failure of wood at its connection are studied in some articles. But to research the characterization and to evaluate that fracture is very difficult. Now we have no standard method to determine the fracture toughness of wood for timber engineering. So we need some simple or useful methods.
On the past study, we conducted CT tests with some woods for structural glulam which width is 47mm. However, we didn't under stand the fracture features which size is large, and the fracture toughness. Then we conducted additional CT tests, used its width and crack length as the parameter. Durning the tests, we checked behaviour of crack on the surfaces as the same in the previours study. As result we understood that fracture of wood starts at maximum load or after that, and the fracture feature differs when we differ the size of specimens. In other words, in the case the width is under 94mm and the dimensionless-crack-length in over 0.5, the fracture feature is in ductile and we can obtain J_1C in stable. Next we conducted CT tests with different strength-graded wood which width is 47mm. As the results, the J_1C doesn't almost differ as the grading it different.

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The wall strength magnification ratio of mud wall of the defined specification was revised by the Ministry of Land, Infrastructure and Transport notification No. 1543 in 2004. The used material and the manufacture method for mud wall change with areas. While manufacture method and used material differ, the specifications of mud wall differ, which causes structure performance differ. In this paper, the various lathwork of mud wall and materials from mud of wall which are performed in various areas have been investigated. Based on investigated results the experimental variable of the lathwork of mud wall and use material have been determined. In order to predict the shear behavior of the mud wall in various manufacture states, tests on 129 different types of partial wall have been carried out.

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Recently the high performance shear walls have been developing to prevent structural damages and improve vulnerable wood houses under severe earthquakes. A high performance shear wall consisting of nailed shear wall with high damping rubber was developed in this study. The objective of the study is to evaluate the dynamic shear behavior and to figure out the dependency of temperature and frequency about the shear wall. As the result of dynamic and static loading test of the wall and rubber, it is confirmed that the shear wall can keep the strength even if the strength of nail joints declined, especially in a large displacement. In addition, we tried to calculate load-displacement relationship and then to evaluate the dependency of temperature and frequency of the shear wall, by applying the method the NEESWood project developed. The calculation results showed that the fluctuation in the strength and damping by temperature and frequency of high damping shear wall was reduced in 30% in comparison with rubber only.

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Bending tests were done for ten specimens of tapered wood beam made of Japanese cedar and SPF to find splitting failure loads, and simultaneously tensile and shear tests of coupons cut from the same timbers were done to find material properties. It was verified that the splitting failure takes place when the maximum radial stress along the taper edge, which is derived from stress-function theory, reaches the tensile strength of the wood with the same angle to the grain as the taper of the beam. The well-known methods after Hankinson, Norris, and Tsai-Hill were applied to calculating the tensile strengths at various angles to the grain from the basic strengths parallel and perpendicular to the grain of orthotropic material. It was found that Norris and Tsai-Hill formulae are both available to give a good prediction, while Hankinson formula shows a larger dispersion.

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In this paper, the equations to calculate the seismic response of buildings considering precise effect of the soil at the building site are presented. These equations are readily used for the seismic design of buildings. Based on the equations, effect of the strength of building and soil on seismic response was discussed. It is found that seismic responses, particularly those of the buildings with short or long natural periods significantly differ depending on accuracy of soil amplification. Finally, the availability of this calculation method is confirmed by time-history seismic response analysis.

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In this paper, the dynamic analysis of buildings considering soil-structure interaction whose base shears was defined by Calculation of Lateral Load Carrying Capacity and Calculation of Response and Limit Strength depending on the design ductility of buildings was conducted.
The response ductility of buildings with the base shear by Calculation of Response and Limit Strength based on accurate value of soil amplification agreed well to the design ductility, however both response ductility by Calculation of Response and Limit Strength based on simplified value of soil amplification and that by Calculation of Lateral Load Carrying Capacity showed significant difference from the design ductility.

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Currently, it is becoming a common practice in Japan to make slits at the edges of spandrel- or wing-walls where they are connected to columns or beams. The main reason of this practice is that it is difficult to model such walls without slits in structural design. This practice, however, tends to decrease both stiffness and strength of building while increasing construction cost. In this paper, we propose simple methods to estimate allowable- and ultimate-bending-moments and yield deflections of members with such walls.

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In order to simulate the collapse process of a six-story full-scale wall-frame building tested at E-Defense in January 2006, analytical studies were carried out before and after test. In the preliminary analysis executed prior to the test, the effects of analytical model characteristics, shear-span to depth ratio of short column and torsional response on seismic behavior of a specimen were investigated. And after test, numerical simulation of the experimental response was conducted by modeling the behavior of each frame with different kinds of models characterized by the capability of simulating strength degradation, which is based on the preliminary analysis results and observed experiment results. It is shown that post-peak response characterized by strength deterioration and displacement concentration on the 1^st story can be simulated from the analytical model employed in shear critical members such as short column and shear wall, although analytical results underestimate both base shear force and displacement obtained from experiment.

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This paper describes an experimental investigation on the lateral force-resisting mechanism of concrete block infilled R/C frames through measuring internal forces. A series of structural tests was conducted using several types of specimens: one bare and two infilled specimens. In particular, a new force-measuring system was developed and applied to one of the infilled specimens to obtain experimental data on internal forces. The results of force measurements revealed not only stress concentrations at the column bottom but also their mechanism. The seismic performance of R/C columns in this kind of structure was significantly affected by nonstructural block walls.

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The Winklerian model with springs on the both sides of the wall is a method of analysis to make analysis precision of the displacement of earth retaining walls better. The design of earth retaining walls by this model demands the values such as initial earth pressure, active earth pressure, equivalent earth pressure and soil reaction modulus.
This paper shows a presumed expression based on many measurements of lateral earth pressure and a case history of the behavior of practical excavation work.

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In a shake table test conducted on a full-scale 4 story steel building at the E-Defense, various non-structural components were installed to the specimen to evaluate their seismic performance. Among these components, this paper addresses the external walls which consist of ALC (autoclaved lightweight aerated concrete) panels, aluminum sashes and glass windows, and examined the following subjects.
1. The results of observations of the external walls after the experiment.
2. The rotation behavior of the ALC panels and their damage process.
3. The effect of the external walls on the steel structures.

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The authors conceived the buckling-restrained brace providing stable hysteretic characteristic even under high-strain conditions. In the past paper, conducting cyclically static loading tests, the performance evaluation formula of the buckling-restrained brace was designed and defined strict scope of application. However, these experimental results were based on the same length of specimens. Therefore, effects of plastic length ratios were not considered. In this paper, specimens of different lengths are fabricated and tested. As a result, the performance evaluation formula is fulfilled between 30% and 80% of plastic length ratio. Performance is increased by increasing plastic length ratio. The specimen that plastic length ratio is approximately 30% retains the performance evaluation formula even in high restraining forces. And a relationship of buckling mode and plastic length is linear.

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In this paper, design criteria of buckling-restrained brace (BRB) to prevent out-of-plane buckling are proposed. The proposed criteria are as follows; (1) buckling member is decided to keep elastic, (2) the distance of lateral stiffners must be smaller than the require distance in case of inverted-V bracing, and (3) connections are decided to keep elastic in consideration with story drift angle in orthogonal frame. To confirm the third criterion, experimental verification of BRBs with connections is conducted. As a result, it is clarified that out-of-plane buckling occurs if the end of connection yields by axial force and bending moment.

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This paper shows the experimental and analytical study on the lattice wall bearing the lateral forces. The specimens were manufactured by welding steel flat bars that were diagonally crossed each other. Each specimen was subjected to cyclic loading in lateral direction. The ultimate strength was governed by the buckling and the hysteresis loop showed the slip behavior. The axial force distribution was also investigated by finite element analysis in order to identify the effective elements in transmitting the stress. Finally, the estimation method of the maximum strength, the strength during slipping and the post-buckling strength was derived from the analytical results.

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This study was conducted to confirm the structural performances of the brick wall against the horizontal bending forces out of plane. Three types of the method of laying bricks were tested. The first was constructed in a normal method, of which vertical joints were not stuffed completely. The second was infused the vacancies of the joint mortals with the cement slurry to strengthen brick walls, after constructed in a normal method. The third was constructed of the joints stuffed completely, in order to make an analysis of the bending destruction method. As a result of tests, the strengthening effects of infusing the cement slurry were confirmed. The experimental values were compared to the values based on the formula presented by the previous study.

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