Durability of reinforced concrete structure depends on the quality of the concrete cover that inhibits the rebar corrosion in concrete. Hence, for evaluating the performance of concrete cover to resist the rebar corrosion in concrete, authors proposed "Drill-PR method" using the permeability velocity and resistivity measured by the hole drilled in the surface of concrete. In this paper, several kinds of concrete were prepared for an experimental study on the application of Figg's intrusive method and resistivity test method (Wenner method) to the Drill-PR method. The Student's t-statistical analysis of the test results indicates a good capability of the air-permeability by Figg's intrusive method for evaluating the performance of concrete cover to resist the rebar corrosion. It was also known that the resistivity test method was significantly affected by the water cement ratio, moisture content of concrete and relative humidity. Based on the results of these experiments, authors proposed a classification for the performance of concrete cover to resist the rebar corrosion in concrete.

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We investigated the amount of hexavalent chromium Cr(VI), which was released from the concrete waste crushed at the intermediate disposal processing plants located round Tokyo, and also examined the influences of various test conditions upon the amount of Cr(VI) released.
As a result, it was found that the amount of Cr(VI) released from some of the samples was beyond the prescribed level and that some of the influencing factors upon the leaching characteristics were identified. It was difficult to evaluate the environmental safety of crushed concrete by single batch test.

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The electronic devices like a cell phone and a wireless LAN using the electromagnetic wave are rapidly widespread recently. The trouble in an architectural space by the electromagnetic wave has expanded on the other hand of the electromagnetic compatibility, too. In the improvement of an architectural space, the research of the electric wave characteristic of the building material is important. In this paper, the reflection loss of the building materials generally used for the building in the UHF band (550MHz-650MHz) and the semi-microwave band (1600MHz-2600MHz) is measured. As a result of the measurement, the following have been understood.
 1. In the UHF band, when the lattice type ferrite microwave absorber was used, the reflection loss of 20dB was shown. When the roof tile or carpet was used, a high reflection loss was shown.
 2. In the semi-microwave band, a little large reflection loss was shown by the lattice type ferrite microwave absorber, the rock fiber acoustic material, and the aluminum heat insulator.
 3. Measured building materials divided into the following four kinds. 1) Material that shows the reflection loss in the UHF band. 2) Materials that shows the reflection loss in the semi-microwave band. 3) Material that shows the reflection loss in both frequency bands. 4) Material that doesn't show the reflection loss in neither the UHF band nor the semi-microwave band.

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We have been developing a soiling simulation system to predict visual deterioration of building outer walls. In this study, we focused on the striped soiling on the walls under windows. At first, we collected the photos of already soiled walls. Secondly, we quantified soiling patterns as the model formula. At last, we established the soiling predictive model derived from the data of actual walls. By using the predictive model, we made a piece of software which can output soiling predictive images. To confirm the results, we compared the soiling predictive images with photos of already soiled walls.

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This paper describes evaluation on wind resistance performance of roof frame in timber structure subjected to high wind. Pulling -up load tests were carried out to evaluate strength of several connection types in rafter or vertical roof strut. By using the result of load test, probabilistic model based on the structural reliability concept was developed for the connections in edge of eaves and the connections in roof strut under the gable, where lots of high wind-induced damage can be seen. This model showed that the probability of failure starts to increase under instantaneous wind velocity of 40 to 70m/s in the former connections, 50 to 70m/s in the latter ones, respectively. Based on results of the probabilistic analysis, the authors tried to propose construction method of the related roof connections which can be suitable to the mean wind speed considered in the construction site.

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This paper investigates the effectiveness of upgrading existing non-conforming school buildings as well as wooden houses in Nagoya from the viewpoint of the reduction of risk of refugees to overflow. The risk is estimated for each school district taking into account the seismic performance level of the school buildings based on the seismic evaluation. Such risk information can be used as a basis of decision making for a government to give priority to upgrade the school buildings. It can also be used for house owners to make decision to which level they upgrade their houses and also to which school they take refuges.

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The evaluating method of seismic load has been studied as the matter how to be ruled safety and reasonably from long ago in Japan. Some calculation formulas to lay down the value of seismic load were suggested, but they were based on incomplete evidence such as by heuristics or expectancy. This seismic load value used the same one ruled over 65 years ago without logical way of evidence by inspection is applied to the current Building Standard Low. In this study, we implemented the shaking table test of furniture with horizontal load cell. By seismic behavior of furniture, the observed value by load cell will be supposed to be reduced cause of their “Effective Mass”, whici has an effect on horizontal shear force. The purpose of this paper is: 1) Watching seismic behaviors of furniture in various installation conditions, 2) Working out the “Effective Mass” of furniture in the logical way, 3) Weighing between observed behavior and “Effective Mass”.

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This study investigates the effects of inclination angle and yaw angle for wind forces acting on inclined circular cylinders. In this study, wind forces per unit length acting on the cylinders are measured simultaneously at all positions by using a manifold system. From this study, the following results are obtained;
 (1) The modal wind forces acting on the inclined circular cylinders and the Strouhal number are followed to the Cosine Rule or the Independence Principle. Those data are characterized by equivalent yaw angle, which combined with inclination angle and yaw angle. (2) The fluctuating across wind forces transmit from up-stream side to down-stream side in a constant speed. The transmission speed of the fluctuating across wind forces is able to be approximated to a liner function of equivalent yaw angle. (3) The characteristics of wind forces in a uniform flow and a turbulent flow are almost same.

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Large amount of ground motion records has been accumulated at stations of existing K-NET, KiK-net and other observation network systems throughout Japan. They have been utilized in various ways such as deeper understanding of earthquake source and characteristics and wave propagation characteristics, establishment of more precise ground motion attenuation relationships, application to early warning systems, etc. The past attenuation relationships for PGA, PGV, or other intensity measures of ground motion have been established through regression analyses of observed records. They can be easily used for wide range of applications. Shortcomings of the traditional attenuation relationships, however, can only predict the attenuation property of a single intensity measures, not the whole attenuation property of ground motions. It is presented in this paper that a new and easy-to-use selection method of records from ample observed earthquake records inventory (Data-base) is proposed instead of establishing another attenuation relationship.

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This paper proposes a seismic peak response evaluation method for slip-hysteretic structure having a viscous or viscoelastic damper. Formulations to estimate equivalent vibration period and equivalent damping ratio of the slip-hysteretic structure subjected to random excitation are presented. The peak response evaluation method is based on equivalent linearization as well as spectrum modification and reduction, reflecting increase in equivalent vibration period and equivalent damping ratio. Accuracy of the evaluation method is validated through numerous time history analyses, over a wide range of viscous damping ratio, elastic vibration period, post-yield stiffness, slip strength ratio, ductility ratio, and earthquake type.

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This paper improves an identification method of stiffness matrix for an MDOF linear shear building model. The method can guarantee that the identification result conforms to the modal information that has been evaluated before through the same vibration record. The least squares method with weighting factors is utilized to linearly calculate the structural parameters by considering the modal identification result as constraint condition. Numerical simulation indicates that the modal constraint improves robustness in the stiffness identification. The method is applied to shaking table tests of a 0.3-scale six-story steel frame to study damage detection. A sudden drop in identified stiffness shows structural damage in the corresponding story.

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This paper describes the experimental study on heat-mechanics interaction behavior of laminated rubber bearings, such as lead rubber bearings (LRB) and high damping rubber bearings (HDB) under larger and more cyclic lateral deformation. For the rubber bearings installed to the base-isolated structures, the seismic energy they absorb is transformed into the thermal energy, so heat is generated causing high temperatures in the lead plug and high damping rubber. There are few experimental data so far, especially using full-scale specimen for heat-mechanics interaction behavior. Dynamic loading tests were conducted using full-scale and reduced-scale rubber bearing specimens under the sinusoidal and the earthquake response displacement inputs to confirm the effects of damping characteristics in line with the rising temperatures. The results of the tests show that the damping characteristics of the rubber bearings were deteriorated under the influence of the temperature rise and the similarity low is approved for the different size of rubber bearings.

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When a building with viscoelastic dampers is subjected to wind excitations, its dynamic properties such as vibration period and damping ratio can vary, depending on the frequency contents of the excitation. This is due to frequency sensitivity of the viscoelastic damper, and contradicts with the basis of the conventional spectral or modal analysis method using the constant dynamic properties evaluated at resonant state of the building. This paper points out the need for considering frequency sensitivity of a building when it possesses velocity-dependent dampers such as viscoelastic dampers, and proposes for the first time a new spectral or modal analysis method to predict the wind-induced response, considering the frequency sensitivity of the viscoelastic damper.

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Although the quantitative load-settlement relationships of spread foundation have been experimentally well demonstrated on sand ground, the underlying dynamic properties of the relationship remain to be elucidated. Here we present the theoretical properties which were derived from circular footing model experiment and computer simulation. The model experiment was carried out through vertical loading of circular footing dense sand ground in soil tank with different volumes. The quantitative link of load and settlement was analyzed by FEM simulation with SMP-Cam-Clay model which was estimable of sand dilatancy. Comparison of the analytical data with the critical bearing capacity based on Terzaghi's theory lead to the following results: In the soil tank with a large volume and at Terzaghi's critical capacity, sand behavior shifts from continuous to discontinuous, and consequently results in total failure. With regards to a small tank, on the other hand, positive dilatancy exerts a marked binding effect of a soil tank rectangle. Accordingly, the dilatancy causes the increase of mean principal stress and the load exceeds the Terzaghi's critical bearing capacity.

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Damping is one of the important parameters about vibration phenomena of structures. However it is impossible to evaluate damping ratios by theory or to know ones in apriority from structural systems because there are many environmental factors around and in the structures, for example, those are wind forces, seismic forces, inner frictions in the structures and so on. Recently, accurate damping evaluation has been very important role in a design stage of structures. Damping ratios are tried to make clear through microtremor observations of three shell and spatial structures, and a database consist of 48 samples including the three structures has been made. From these results, the damping characteristics of shell and spatial structures are roughly grasped and choosing the appropriate processing method of the wave data is discussed.

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In this study, nailed joints supposing to be used in the shear walls of wooden houses were exposed in high temperature and humidity in order to accelerate rust development on the nails. The shear tests were conducted on the deteriorated specimens. As the result,
1. As the rust development progressed, the failure mode tended to change from withdrawal to nail-head pull-through.
2. The rating of the nail was adequate to representing the tendency of the shearing performance at the early stage of deterioration, but the later stage, the other parameters were more appropriate.
3. The each factor of the allowable resistance showed different tendencies, as the deterioration advanced.
In addition, the formula of the lateral resistance for the piles was tried to apply to the simplified prediction of the load-deformation relations with characteristic value estimated by simple element tests.

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This paper attempts to clear large deformation behaviors of two story wooden frame houses and to predict large deformation behaviors of two story wooden frame houses from the summation of static performances of two story wooden frame walls that compose those houses. 4 types of wooden frame houses and walls are tested. The comparison of the results between two story wooden frame houses and the summation walls indicates, 1) until 1/30-1/25rad. deformation of 1st story, the summation of walls can predict structural performances of two story wooden frame houses without the influence of joint type of the column or the existences of boards, 2) after 1/25rad. deformation of 1st story, the structural performance of the summation of walls become different from that ones because failure modes of brace in walls is different from those of houses.

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The main objective of this study is to define hysteretic model for deterministic nonlinear time-history analyses of Japanese conventional wood houses under various earthquake ground motion. In part 1 report, three models which are combination of elasto-plastic and slip model, Takeda model for reinforce concrete beam member and Magara model are compared to confirm the applicability. In this study, the modified model based on Evolutionary Parameter Hysteretic Model is proposed. The modifications are: A) Reloading and unloading path is revised to fit with the result of cyclic loading tests, B) Consideration of degradation of backbone curve due to the cyclic loading, C) Consideration of degradation of plus or minus displacement. The comparison of the model and tests, which are stable displacement cyclic test, pseudo dynamic test and so on proofs the applicability of proposed model.

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The purposes of this study were to examine the shear resistance mechanism and the parameter's effect on the capacity at slip displacement of 2mm for bonded anchor subjected to shear force. In order to investigate this objective, a shear experiment of 300 specimens with 60 kinds, which consist of 4 types parameters such as embedment length, compressive strength of concrete, diameter and yield strength of steel bar, were carried out.
In the analysis, the mechanism was discussed as the resistances of dowel effect, and the relationship between bearing pressure and diameter of steel bar was considered here. Based on this analysis, formula for shear capacity by dowel effect was proposed for the case when the shear resistance within slip displacement σs=2mm was attained by the bearing pressure strength.

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In recent earthquakes, the number of cyclic loadings has exceeded that expected. Some experiments were conducted on reinforced concrete elements subjected to many cyclic loadings. The following observations are notable. 1) Slip-stiffness degradation occurs and the hysteretic shape tends to become reverse S-shaped. As a result, hysteretic energy decreases for every cyclic loading. 2) A directional point transfers to large deformation. A new hysteretic model was developed for reinforced concrete elements, which can be considered as slip-stiffness degradation and transference of directional point. Earthquake response analyses of reinforced concrete model buildings for long-period ground motion were conducted using the developed hysteretic model. The maximum response didn't increase greatly from that with the TAKEDA model.

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Guidelines of the shear stiffness of the corrugated steel plate are made in Europe and the USA. However, these guidelines are greatly different mutually. Then, this study shows the shear stiffness of the corrugated steel plate in detail, in order to aim at using as shear resistance panel. In this study, the energy method and F.E.M are carried out to clear the influence of corrugated shape, boundary condition and wave number on the shear stiffness of the corrugated steel plate. As a result, the diagram for evaluating the shear stiffness of the corrugated steel plate from these shape are shown.

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The buckling loads of columns with various boundary conditions and portal frames subjected to vertical loads on the top of the columns are calculated on the basis of the Reissner's Principle. In the analysis, the deflection and bending moment are assumed by polynomials. Total nine cases for polynomials are treated. In some cases, the buckling loads are obtained conservatively, comparing with the exact solutions. After that the alternative formula for evaluating an effective length factor of columns in a braced symmetrical frame is proposed. It is shown that the effective length obtained by the proposal formula agrees well and conservatively with the correct value.

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In the past, it was shown that H-shaped beams with large depth-thickness ratio are useful as a seismic design beam. But, under cyclic loading, the characteristics of these beams have not been examined enough. So in this study, the cyclic behavior, plastic deformation capacity and energy absorption ability of H-shaped beams having larger depth-thickness ratio than the limit of current standard are examined by cyclic experiments and numerical analysis. And the new limit value of plate slenderness are proposed. The plate local post-buckling behaviors of these beams are considered and modeled for progressive use in the future.

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The objective of this study is to develop weld-free beam-to-column connection for H-SA700A high strength steel members, and verify the structural behavior of the proposed connections. Knee brace damper and friction damper were used to connect beam and column by high strength bolts; the trigger level of these dampers were designed to remain beam and column as elastic. Full-scale testing of knee-brace connection showed that damper yielded at the target level and all part of the connections performed as expected. Friction damper, which aluminum is sprayed at the surface, obtained 0.7 as the slip coefficient and a stable elasto-plastic structural behavior were observed after the slippage.

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In order to investigate the seismic performance of a new hybrid structural system which is consisted of self-centering open frames and energy dissipation walls, the dynamic response analysis of the structural model has been carried out. The analytical model of the energy dissipation wall was already verified by the comparisons between the test results of the three-story wall specimens and its elasto-plastic analysis. In this paper, the analytical model of the self-centering frame is discussed on the bases of our previous experimental work. The simple calculating method for the horizontal load carrying capacities of the frames is developed. Also, the analytical model based on the stress-strain relation of the material is developed to simulate the load-deformation relations of the tests. The analytical results trace the characteristic behavior of the test results which are stiffness, maximum strength and residual deformation. The both of the analytical models of wall and frame are combined and used for the dynamic response analysis of the hybrid structural system. The analytical models of the six-story and three-story buildings with the hybrid structural system are made to investigate the structural characteristics. The analytical results show that the proposed hybrid structure possesses both of the high hysteretic damping effect and reduction effect of the residual deformation against the input earthquake motions.

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An experimental study was conducted to evaluate the effects of high temperature and strain rate on the interaction behavior of the local and overall buckling of steel H-section columns at high temperature. On the basis of the experimental results obtained in this study, it was found that the maximum load of H-section columns decreased with increasing the temperature and the gradient in the descending branch of the load-deflection curves was steeper with increasing the width-to-thickness ratios. The maximum load of columns at 600 Celsius was reduced to 30%(in the case of slow strain-rate test), 40%(in the case of fast strain-rate test) of the maximum load at room temperature and was very sensitive to the strain rate. The results of the numerical simulations clearly showed that numerical analyses can be used to provide accurate predictions of the buckling characteristics of columns at high temperatures.

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