The two measurement methods of electromagnetic characteristic have developed by using the parallel wire line in the UHF band(400-800MHz). One is the measurement method of the return loss in the vertical electromagnetic wave, the other is the return loss in the diagonal electromagnetic wave. The types of electromagnetic absorption are a single layer type and a double layers type. The return loss of single layer is almost low, that of double layers has been improved. The combinations of recycling board and cement mortar mixed with electromagnetic absorption materials affect the electromagnetic characteristic of the return loss. The return loss in the diagonal wave can be calculated with the reflection coefficient and the angle of incidence. When the distance between absorption and reflection plate is one fourth of wave length, the return loss is bigger than that of the other distance.

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In a case of prolonged service life of old concrete structures by repair works, prediction technique of service life after repair is necessary to design durability of repaired structures. In this paper, carbonation speed about concrete repaired by several types of repair materials after carbonation were examined. Air permeability, pore size distribution, and carbonation speed of repair materials were also examined. And effects of these repair materials on carbonation speed of concrete were confirmed. From these results, some expression to predict prolonged service life that the carbonation speed of concrete repaired correlates closely with the air permeability and carbonation speed of repairing materials was proposed. And the flow of selecting repair materials for prolonged service life of old concrete structures, was proposed.

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The probability distribution of compressive strength class of any kinds of concrete was definied as normal distribution in quality control even in structure concrete. It is clear that the peak of distribution is higher than the mean value of strength in high strength concrete, nevertheless the mean value is equal to the peak of distribution in ordinary strength class of concrete. In this report, it was clarified that the shape of probability distribution of compressive strength of core specimens in high strength concrete structures was not normal distribution. So, if the probabilistic property of concrete strength is assumed to follow a normal distribution in quality control, it makes the strength lower than the design strength in structure concrete.

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In this paper, a fundamental study is carried out to clarify the compression softening characteristics of fiber reinforced cementitious composite focusing on the fiber volume fraction and the size effect parameters. Based on the compression tests, the compression softening parameters of both post-peak displacement and post-peak strain are evaluated, and a simple linear softening model is applied to finite element analysis in order to predict the experimental results. The analytical predictions indicate that the simple linear softening model is applicable and both the fiber volume fraction and the size effect parameters should be considered to achieve the further reliability.

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The damaged RC structures due to corrosion of embedded steel bars are usually repaired by such repair materials as polymer modified cement mortar (PCM). Compatibility in dimension, permeability, and chemical and electrochemical properties with existing concrete are required for repair materials in optimal repair system. There is, however, little information about performance of repair materials over time. In this paper changes of such properties as air permeability, water penetration and capillary water suction in PCM were investigated under cyclic accelerated environmental condition, i.e. wetting-and-drying and high-and-low temperature. The experimental results are discussed based on the change of micro-pore size distribution. The patterns of degradation of PCM are classified into two types, i.e. the deterioration in PCM matrix and the damage in surface polymer film.

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The objective of this paper is to show the applicability of the LES method to the realistic problem such as the vortex-induced oscillation of high-rise RC cylindrical tower in turbulent boundary layer. First, we introduce the numerical method for generating the boundary-layer turbulence to the present LES method. Next, we study the fundamental characteristics for the vortex-induced oscillation of a three dimensional circular cylinder in turbulent boundary layer. Finally, the response characteristics and the physical mechanism of the vortex-induced oscillation of the high-rise RC cylindrical tower are investigated by the present LES method.

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Among many kinds of passive energy dissipation systems, recently velocity-dependent dampers have been used for reducing seismic response of building frames. It is practical to study using simple and accurate analytical model in determining damper quantity and locations in seismic design. A series of dynamic response analyses are carried out using simple or accurate types of modeling for a 8 stories steel frames. This paper presents a comparison of differences caused by modeling technique and effects of damper quantity on seismic performance based on complex first mode. A simplified calibration method of analytical model based on effective damper deformations, and static convergence calculation method for calculating effective damper deformations are also proposed.

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This paper describes earthquake response prediction methods and rationalization of dynamic design of mid-story isolated buildings. At first expressions of earthquake responses of the isolation story and first story, which dominate the seismic performance, are shown. Then, by drafting nomograph of relationship between maximum responses, it is shown that earthquake responses and response reduction by dampers and structural damping can be evaluated without using time history analysis. The dynamic design of mid-story isolated buildings are rationalized on an equality with base isolated buildings by flowcharting earthquake response prediction.

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Mid and high rise buildings having a natural period of about one second suffer inevitable damage under severe earthquake ground motion, although dampers are installed. This study is to clear up the effect of frame plasticity to seismic response deformation on passively vibration-controlled buildings. Based on the equivalent linearization technique, it is shown that response deformation is increased by frame plasticity but increment is few and the relationship between amount of dampers and main-frame damage can be estimated quantitatively.

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A method to detect P-to-S converted waves from seismic bedrock is proposed and applied to strong motion records observed at two KiK-net stations. In this method, receiver function RF derived from radial-to-vertical spectral ratios for P-waves is deconvolved to minimum-phase-shift function and all-pass function. The all-pass function (all-pass RF) has liner phase and so it is purely reserved the PS-P time, which is time difference between P-to-S converted waves and P waves. Consequently all-pass RF has a clear peak at a PS-P time. It is shown using the strong motion records that the PS-P time is well estimated from all-pass RF of each record without stacking of many records.

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The study of the steady-state vibration of a system under sinusoidal excitation can provide important insights into the more general dynamic response structures. The response of seismically-isolated structures with viscously-damped isolation system was previously studied by the authors. This paper presents the non-linear steady-state vibration of seismically-isolated structures with hysteretically-damping isolation system. The solution method for the steady-state vibration of the non-linear system is based on the work of Tajimi, and expanded to seismically-isolated structures. The non-linear superstructure behavior is significantly different from that of fixed-base structure. Consequently, the important aspects for isolated structure design is highlighted.

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This study proposes an optimal selection method for base-isolation devices in a mid-story isolation structure using a genetic algorithm. Parameters employed in the genetic algorithm's evaluation functions are: A) eccentricity ratio, B) vertical load on each isolator, C) temporary load on each isolator, D) natural period, E) yield force coefficient of base isolation devices, F) the maximum response displacement of isolation devices, G) storey shear force coefficient and H) base isolation displacement. We employed three groups of parameters: (1). A-B-C-D-E, (2). A-B-C-E-F, (3). A-B-C-G-H. We did time history response analyses with buildings designed by the proposed method. As the result, the response value was suppressed in case of (3). Therefore, the proposed method is effective for selection isolation devices for mid-story isolation buildings.

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We wish to report on the results of various kinds of experiments on the slurry of cast-in-place concrete pile. These experiments were conducted to improve the bond strength between concrete and reinforcing bars in slurry. At first, we investigated the relationship between the density of slurry, current flowing time of slurry and quantity of bentonite attached to the surface of the reinforcing bar. As a result, it was found that this adhesion occurred due to an electro-chemical phenomena. This information helped us find the correct dispersion material, polycarboxylate-system high polymer compound.

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Shaking table tests are conducted to investigate an influence of soil density on lateral ground force acting on a pile, namely, subgrade reaction in liquefied sand. It is shown that (1) The subgrade reaction mainly acts on a pile as an external force in loose saturated sand, and as a reaction force in dense saturated sand; (2)The bending moment at pile head in medium dense sand is larger than those in loose sand and dense sand; (3)The lateral ground force acting on a pile in loose to dense sand has character of solid ground due to decrease of excess power water pressure and recovery of effective normal stress during liquefaction.

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The main purpose of this study is to investigate, both experimentally and theoretically, the strength of concrete cylindrical shells with composite carbon fiber reinforcement under concentrated load. It is defined in this study that composite carbon fiber reinforcement consists of carbon fiber chips and carbon fiber sheets. The chips and the sheets could improve the tensile strength of a concrete shell in its internal and external regions, respectively. An experimental study was conducted on concrete shells reinforced with composite carbon fiber under concentrated load. A theoretical study was conducted by material and geometrical nonlinear finite element analyses including tension cutoff and tension stiffening effects. The ultimate strength of the shell with composite carbon fiber reinforcement was discussed on the basis of the results of the fracture experiments and nonlinear analyses.

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In this paper, some results of vibration measurements and analyses of the existing RC arena which passed through 25 years from the construction are shown. From the obtained results, the identification of the vibration characteristics become possible by vibration measurements and 3D-FEM analyses, and the response level of the shell roof is quantitatively predictable from the earthquake response analysis. It will be applicable to the direct estimation of the seismic capacity of the structural members and nonstructural members such as hung ceilings and suspended luminaires.

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In this paper, first we measure microtremors of wooden structures to obtain their natural frequencies. Then we construct three-dimensional structure models based on experiment data, such as beam-column connections, brace-column connections, shear walls with brace and panels, and so on. Next, we compare natural frequencies from microtremors with those acquired from eigenvalue analyses of three-dimensional structure models. We construct inverted elastic models by increasing stiffness until the natural frequency matches with the observed one. Then we examine whether the models are appropriate by comparing its nonlinear behavior with the result of a full-scale shaking table test of a wooden structure. Finally we evaluate the seismic performance of the wooden structures by using earthquake observation records and simulated strong ground motions. We confirmed that the natural periods of wooden structures obtained from microtremor linearly correlate with their wall-length ratios. We also confirmed that dynamic characteristics of structure models could be tuned up to approximate those of mirotremors. Finally we confirmed that modern wooden structures that we studies here seem to have sufficient seismic performance so that they would not be collapsed or heavily damaged for strong ground motions in the near-fault regions.

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Masugumi is one of the most important architectural components in old wooden Japanese buildings in terms of both structure and decoration, and its structural characteristics have been studied in recent years. The purpose of this study is to investigate the structural behaviour of masu-gumi, especially to formularize compressive creep curve in relation to the load duration. By using full-size masugumi component, which was modeled on that in national treasure building "Toshodaiji Kondo", static lateral loading test and compressive creep test for 4 years were carried out. As a result, the calculated results based on the elasto-plastic behaviour of bottom part of masugumi showed good agreement with the experimental ones, and it was estimated that the relative creep (the ratio of total deformation to initial deformation) of 100 years later would be about 5.

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An evaluation method for the earthquake resistant performance of reinforced concrete columns and beams is developed for the performance based design. Six RC column specimens were tested to verify the proposed method. Main features of the proposed method to be verified are 1) transverse and longitudinal stiffness and 2) separation into five regions along the length. Main parameters of the test specimens are the existence of sub tie for transverse reinforcement, the failure mode (i.e. flexure or shear) and the size of specimens. The calculations by the proposed method show good accordance with both the experimental and FEM analytical results. Furthermore calculation method for shear crack width is developed and compared with the experimental results. Calculated crack widths correspond well with the measured ones.

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Using an existing school building that will be demolished in the future, the authors conducted full-scale seismic tests to verify the effects of response control retrofit on actual buildings. It was found, through the pseudo dynamic tests, that the effects of response control retrofit on buildings rehabilitated in the same way as actual retrofit constructions (i.e. installing braces fitted with friction dampers on existing buildings without removing sashes and interior/exterior finishings) is similar to that predicted in design. In addition, useful data, which will allow the extent of damage to seismically retrofitted buildings caused by large earthquake forces to be assumed, were obtained through investigation of damage on major structural members, nonstructural walls, and interior/exterior finishings of the test building.

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In this paper, the horizontal projection length according to the previous and current standards are compared, and by studying on the end bar anchorage of Reinforced Concrete beam paid attention to bar slip, following key points are found. (1)On the horizontal projection length of L2 and l_<dh> according to the previous and current standards, the current standard has set longer length than the one in the previous standard while the concrete strength at a range of 27 to 33N/mm^2. (2)According to the specimens used in this paper, it shows by changing the horizontal projection length l_<dh> at a range of 10.5 to 17.4d_b, the relationship between the main bar stress and the bar slip is hardly effected till the main bar stress reaches _Lf_t. (3)The relationship between bar stress/√ σ_B and bar slip is shown as regression formula in (3) and (4). (4)According to the allowable bar slip, the failure rate and the concrete compressive strength, this study suggests the way of calculating the long term allowable tension stress _Lf_<t2>.

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This paper presents two types of simplified structures of reinforced concrete hinge isolated systems proposed by one of the authors. One is the splice-bar type which consists of main bars and splice bars of beams. The other is the joint-bar type which consists of joint bars fixing beams and beam-column connections, and main bars of beams. The main bars of the splice-bar type and the joint bars of the joint-bar type are un-bonded at the edge parts of beams. The seismic test results excluding those of the specimens with insufficient arrangement of lap splices of the joint-bar type verified the splendid performance of the two types of structures proposed in this paper: the specimens deformed mainly by the rotation due to the wide crack at the beam-ends without any severe damage in the beams.

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During past severe earthquakes, a number of R/C buildings designed by the old codes suffered heavy damages including collapse. To evaluate the seismic performance of old buildings for the ultimate limit state, it is important to study the nature of axial shortening for old columns subjected to earthquake loads. Half-scale model specimens with shear mode simulating old columns were tested until they came to be unable to sustain axial load. Using results of the tests, it was attempted to formulate the relations of vertical and lateral deformation based on the concept of failure surface contraction and theory of plastic flow.

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Authors have devised a seismic response control brace composed of an ordinary axial force member as intermediate member and two the axial hysteresis dampers at its both ends, which is available for industrial frame structures having longer diagonal braces. In the former paper Part 1, the buckling restraint conditions of the brace with the dampers were formulated by developing the beam-column theory. In this paper Part 2, loading tests on six types of the whole brace models are carried out, and the adequacy of the buckling restraint condition theory is verified. And then the cyclic loading tests on the axial hysteresis damper, which consists of the cruciform steel core and the rectangular buckling restraint tube are carried out, so that the accumulative plastic deformation capacity as well the cyclic hysteresis load and deformation relation is discussed.

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In this study, the SRB-DUP (Steel Reinforced Brick based on Distributed Unbond Prestress theory) coupled beam which has the lateral stiffening effect of thin steel plate is proposed. The structural design formula for bending moment on the damage limit state and the initial flexural rigidity of the coupled beam by proposed construction method is verified in the experiment. As a result, it is found that the bending moment when the plastic deformation is occurred in the beam is larger than the bending moment M_<AS> on the damage limit state. And it is found that the initial flexural rigidity analyzed is closed to an experimental value.

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Behavior of a circular concrete-filled steel tube (CFT) short columns under axial compression is influenced by the interactive effects between steel and concrete. This paper first derives the constitutive equations of the concrete considering the triaxial stress state under the incremental lateral stresses. Second, the numerical formulas for predicting stress-strain behavior of steel tube are proposed based on the experimental results. By using the obtained numerical formulas, the loaddeformation behavior of a circular CFT short column under uniaxial compression is predicted, considering the size effect.

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