In city area, electromagnetic interference caused by buildings is a very important problem. For example, a well known ghost phenomenon is caused by interaction between incident and reflected waves caused due to the presence of large and tall buildings. The characteristics of the radio waves used in television broad casting absorption have been measured by coaxial-wave-guide unit or curtain wall specimens. But these measurements have some demerits. In this regards, a new measurement technique by panel specimen using parallel wire line was proposed recently. The electric wave absorption characteristics of the reinforcing rod inside the reinforced concrete structures are examined using the recently proposed technique. A reinforcing rod in horizontal direction influences electric wave absorption characteristics of the concrete. In this paper, an equation for calculation of average electric wave absorption of concrete structures in presence of reinforcement is proposed taking care of the effect of the distribution of the reinforcement. In this method, an equivalent material characteristics of the composite material is calculated. This method has potential of application in other different composite material also.

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Drying shrinkage strains were measured on thin mortar specimens (4×0.4×14cm) with volume fractions, 0%, 1% and 2% of carbon fibers. The experiments comprised two series (Experiment A and B). In Experiment A, measurements of water loss (W) and drying shrinkage strain (S) with drying time were made, respectively at 10% relative humidity. From the test result W-S relationships were obtained. In Experiment B, drying shrinkage strains were measured at equilibrium under various humidities (h). From the result, h-S relationships were obtained. The results can be summarized as follows; (1) The effect of carbon fiber content on drying shrinkage strain of mortar was negligible. (2) The older the age at the start of drying, the larger the drying shrinkage strain. (3) The mathematical expressions of h-S relationship and W-S relationship which the authors previously proposed for hardened cement pastes were satisfactorily applied for mortars.

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The author is developing the robot for work on outer walls that can operate without scaffolds in order to save labor and to improve safety for painting and picture painting. Then, the author reports in this paper mainly 1. Decision of the target to develop the robot from analysis of conventional works. 2. Conformation of the mechanism to work the robot. 3. Characteristic technologies and qualities of wall picture painting work by the robot.

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The purpose of this study is to establish the evaluation method of the fracture of framed floors under dynamic loads affected by physical bodies. First, we measured dynamic loads affected by rigid steel bodies, and showed relations between maximum loads and masses of rigid steel bodies under each condition (stiffness of framed floor and falling height). Next, we measured dynamic loads affected by some physical bodies, and obtained each actual mass by means of the relation. As a result, in this paper part 1, we presented the substitution method of loads affected by that of physical bodies to mechanical loading systems.

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Up to now, the study on the probability of structural failure during its service period has been formulated on the assumption that the structural failure belongs to the artificial event where structures can recover immediately after collapsing due to earthquake or that it belongs the event with perfect correlation for each level of intensity of earthquake. This paper describes a new practical method in the evaluation of the probability of failure of the structures with strength deterioration for earthquake loads during its services period, considering the non-failure effect derived from formulating the statistics for the residual strength of survived structures.

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The present paper is a continuation of reporting on research on the wind resistant performance of circular arches that support a barrel roof. The paper discusses not only the characteristics of stress caused by wind pressure in statically determinate arches with differing rise ratios and span ratios, but also the validity of the equivalent static evaluation of wind loads on such arches. The discussion intends to demonstrate the following. (1) A statically determinate arch with a low rise arch has greater maximum bending moment and maximum shearing force, but smaller maximum axial force, than a two-hinged arch. (2) The maximum axial force of a statically determinate arch is consistently greater as rise ratio is greater. Maximum bending moment and maximum shearing force change little relative to change in rise ratio. (3) In a statically determinate arch in the center of a roof, wind blowing along the arch span generates maximum and average stress distributions of similar form. (4) It is possible to perform an equivalent static evaluation of the maximum stress generated in a statically determinate arch in the center of a roof by using average stress and the gust influence factor on stress.

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Motion-induced wind forces on two-dimensional rectangular section models with aspect ratio 1, 2 and 3 are investigated by a wind tunnel test using uniform turbulent flow. In this study, the motion-induced wind pressures and wind forces during across-wind vibration and torsional vibration are measured by forced-oscillation method. Furthermore, the wind responses of two dimensional rectangular structures are estimated by spectrum modal analysis using the motion-induced wind forces measured in this study, and the analytical results are compared with the free vibration experimental results.

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Horizontal array observations for vertical long-period microtremors have been performed in the eastern part of Kobe. Phase velocities were evaluated by means of the f-k spectral analysis using the records. However, the deep subsurface structure could not be determined only from the dispersion of phase velocities, because it could be given by some different structures. Then, horizontal-to-vertical spectral ratios at the central point were calculated. Referring the ratios, the optimal structure has been determined. Moreover, the base rock depth distribution under Kobe area shown in the previous paper has been reestimated based on the optimal structure. Combination of the two types of observations makes the deep subsurface structure estimation methodology more reliable and applicable.

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This paper presents a new active control algorithm for MDOF structures with mass damper systems. The algorithm is created by newly introducing the concept of participation functions of the controlled mass damper so that the dynamic characteristics of the mass damper, natural frequencies, viscous damping factors, vibrational amplifications and these phase, can be easily identified by comparing those of ideal mass dampers. Accordingly, the feedback gains and feed-forward gain, which are able to realize the ideal dynamic characteristics assigned by a designer, can be easily decided by making use of the knowledge concerning to passively controlled tuned mass dampers.

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The method to identify structural parameters of multi-degree of freedom structures by the wavelet transform of the input and responses is presented. For the input of a white noise, the stiffness matrices and damping matrices for two-degree-of-freedom structure, five-degree-of-freedom structure and simply supported beam modelled by finite elements are tried to be identified and it is proven that the proposed method can be used to detect the change of structural parameters with enough accuracy.

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A towering reinforced concrete(R/C) smokestack of 200m in height of an LNG thermal power plant constructed on a reclaimed land in Osaka bay area were strongly excited during the 1995 Hyogoken Nanbu earthquake. 12 sets of earthquake motion records including either this strong motion or weak motions before and after this event are analysed and studied at the standpoint of changes in predominant periods of the ground and the smokestack. For the ground, fundamental frequency during the strong event is lower than those before the event and those after the event are equal to before. Otherwise, for the smokestack, fundamental frequency during the event is much lower than those before the event, but those after the event are lower than before. The ground is reversible, but the smokestack is nonreversible. Nonlinear behavior of the ground and the smokestack are discussed not only on measured data analysis but also on numerical analysis results by a Penzien-type model adopted for the design of this smokestack.

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The earthquakes which occurred in the northwestern part of Kagoshima prefecture on March 26 and May 13 in 1997 caused severe damage to some reinforced concrete school buildings and wooden houses. Many ground motion records are obtained by the seismographs of JMA and NIED which settled in high density after 1995 Hyogoken-Nanbu Earthquake. The response spectra of the ground motion of four sites which surround the seismic region are analyzed. The large peak ground accelerations such as 728 cm/s^2 at Izumi or 902 cm/s^2 at Miyanojyo are recorded but did not cause no severe damage of buildings near seismographs. These records contain predominant high frequencies of over 5 Hz. The response spectra of four sites are different by the location to the seismic region.

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Accurate analytical-solutions are obtained for the free vibration of Mindlin plates resting on point supports symmetrical distribution about the plate axis. By using the method of superimposition, it is shown that solutions which satisfy both the differential equation and the boundary conditions are obtained. The rectangular plates under consideration are as follows: a) all edges free and b) all edges simple support. Eigenvalues of four digit accuracy are provided for a wide range of plate aspect ratio. Numerical results are compared with those by Rayleigh-Ritz method, to verify the accuracy of the proposed method.

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Dynamic soil-structure interaction analysis method is presented for pile foundations in layered fluid-filled poroelastic soil. Thin layered element solutions for the displacements and the pore water pressure caused by the dynamic ring loads and the dynamic ring source of pore water are derived to calculate the dynamic characteristics of pile foundations. Application of these solutions to soil-pile interaction analysis is presented, and the results of pore water pressure distribution around the single piles are discussed.

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Household questionnaire survey was conducted after the 1993 off Kushiro earthquake via elementary schools of Kushiro city and 9 other towns and villages in the disaster area. It aimed to elucidate human behavior, casualty and fire risks related with housing contents and interior damage and seismic intensity. This study examines the questionnaire data and derives content damage vulnerability functions with independent variable of seismic intensity for different room types and different damage levels. The results indicate kitchen, living room, bedroom and children's room is more susceptible to damage than bathroom, toilet, entrance and stairs.

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The database for the directions of collapsed/tilted wooden houses in the disaster belt during the 1995 Hyogo-ken-Nanbu earthquake, which were made by Matsuda and Takemura (1995), are digitized using a GIS software, and are made for the public use at a Web site: http://kouzou.cc.kogakuin.ac.jp. The total number of data is 2790, and the properties of each data consist of 1) the difference between collapse and tilt for the damaged house, 2) the location of the house (latitude and longitude), and 3) the direction of the collapse or tilt. The tolerances are estimated as 10 to 30 m for the locations, and as 5 to 10 degree for the directions. The directions of collapses are dominant at the south-east in the western part, the north in the central area, and the west in the eastern area of the disaster belt.

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There are a few stations in which strong earthquake motions were recorded simultaneously at structural foundations and on surface of the ground in the 1995 Hyogo-ken Nanbu earthquake. Comparing the maximum accelerations observed at the foundations with those on the ground surface shows that the former is reduced 30%, and 10% for velocity on average. In the area considered to have experienced more severe ground motions e.g. such as larger than 400 gal corresponding to the second step threshold of the present building code of Japan there are no simultaneous recording stations. The surface ground motions are simulated backward from the records of two structures in and near severely damaged zone using soil-structure interaction theory considering non-linearity of both structure and ground. Calculated results show similar reduction tendency to the above-mentioned observed results. It is also deduced that the reduction of peak values on the foundation to the ground surface resulted from amplification of soil layer over the bottom of the structure.

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A method is proposed for designing member sizes of a frame which would satisfy the design constraints under Level-2 design earthquakes. This method consists of two steps. In the first step, a shear building model is used and story stiffnesses and story strengths of the shear model are determined so that the designed shear model would exhibit a specified distribution of interstory ductility factors under the Level-2 design earthquakes. In the second step, member sizes of the frame are transformed from the story stiffnesses and story strengths of the shear building model based on the proposed shear model-frame inverse transformation. In this transformation, the total member weight may be minimized as well as the equivalent transformation of the restoring force characteristics in the story level.

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Up to the present, the lateral stress of pile foundations have been usually designed without superstructure so, from the strict theoretical point of view, the stress and deformation are not considered to be correct. This paper expressed the systematic theory of pile foundation with superstructure by elastic analysis on single layer ground under lateral load. 1. General characteristics of pile foundation are explained not by absolute value but by stress per unit deformation. 2. General characteristics are controlled by non dimensional rotation. θo/(yoβ) or θo/(yoη). 3. Non dimensional rotation is related with ω:the restraint factor of rotation. ω:consists of EcKg(kNm):rigidity of ground beam, E_pI_p(kNm^2):bending rigidity of pile and β or η constant of ground character sties. 4. The stress and deformation of pile foundation are able to be easily calculated using the results of this paper.

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It is necessary to have reasonable designs for foundations to preserve the stability of buildings under earthquakes. So far, it is not clear how the behavior of the foundation beam is affected by the footings, piles, etc. In this study, we have carried out a 2-D elasto-plastic frame analysis on two buildings, and the influence of the piles on the stress of the foundation beam and the load-carrying capacity of the structure was evaluated.

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This paper reports the experimental results of reinforced concrete L-shaped section shear walls that has the maximum load before longitudinal bar of boundary column yields. The stress transfer mechanism of L-shaped section shear wall is discussed and the ultimate strength equation of L-shaped section shear walls is derived. The calculated value by the equation proposed in this paper agrees well with the test results.

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This paper presents the results of an experimental work carried out to study the strength and behavior of square steel tubular beam-columns under constant vertical and varying horizontal loads. Width-thickness ratios and axial load ratios are selected as main test parameters. From the test results, the maximum strengths of the cross section are examined, and the method for calculating the strength of columns with large width-thickness ratio is proposed. Moreover, the column strength formula for the plastic design is compared with the test results to check the validity for tubular beam-columns.

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In this paper, the effect of partial loss of sectional area at the flange of H-beams due to bolt holes on the statical characteristics were experimentally investigated in three test series. The test results show that such effect is estimated by considering not only the loss of sectional area of flange plates but also the reduction of plastic section modulus. When the rate of reduction of sectional area is smaller than 25%, such reduction of sectional area has small influence upon the statical characteristics of the beam. And it becomes clear that maximum strength and plastic deformation capacity decrease with increasing the rate of partial loss of sectional area, and that the reduction of maximum strength and plastic deformation capacity can be compensated by using high strength bolted friction joints at the part of bolt holes.

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This study aims at simulating the fracture of beam-to-column connections under the Hyogoken-nanbu earthquake. Specimens composed of H-shaped beams and box columns were subjected to seismic motions by means of shaking table test, and the ultimate behavior was examined. The following results were obtained. (1) All specimens showed high deformation capacities and negative effects of dynamic loading were not observed. (2) High toughness of material reduces the sensitivity to geometrical notch effects and is useful to prevent brittle fracture.

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It has been pointed out that the strain rate affects on the ductility of mild steel. For the steel moment frame of the strong column type, the strain rate at the end of the beam flange is determined by the rotational velocity. The velocity is almost equals to the interstory velocity when the beam is in the plastic region. In this paper, the various elasto-plastic multi-degree of freedom systems are analyzed with the parameters of input motions, number of story, story height and hysteretic characteristics. The maximum interstory velocity is about 0.1rad/s and 0.2rad/s at most. To estimate the maximum interstory velocity, the velocity is examined theoretically and the estimate method is proposed. The velocity of the theoretical estimation is roughly equals to that of the dynamic responses.

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The objectives is to study the strength and behavior of concrete filled steel circular tubular columns subjected to constant compressive load and repeated bending. As the test parameter, diameter-thickness ratio of steel tube, axial load ratio on a column and existence of filled concrete are selected. Total forty concrete filled steel tubular columns are tested. From the test results, inelastic behavior, maximum strength, energy dissipation capacity and deformation capacity are discussed. We have shown relations between axial load ratio and critical rotation angle of a column.

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Loading tests were conducted to evaluate the structural behavior of connection panel, which consisted of connection between steel beam and high-strength concrete-filled circular tubular steel column. Elasto-plastic behavior of the connection panels were also analytically examined. This panel was modeled by superposing tri-linear relations for steel tube and filled concrete. For the latter component, the authors proposed to evaluate load resistance, in which a new theoretical arch mechanism was adopted in consideration of the confined effects of tube. The proposed analytical method was verified by examining preceding experimental results and those in this study, ranging from ordinary strengths to high strengths of steel and concrete. As a result, the analytical results proposed in this paper were found in agreement with the experimental results up to the maximum shearing capacity of concrete, although the analytical results tend to slightly underestimate the experimental results over the displacement range above the maximum shearing capacity of concrete.

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This paper is intended to study the evaluating method of fire resistance of thermal insulation materials such as phenolic foam, phenol modified polyurethane foam (phenol-urethane foam) or polyurethane foam, etc., comparing the fire resistance efficiency of these thermal insulation materials. It was tried to measure the flaming time, burning time, rate of heat release, carbonized extent, etc., immediately after a heat steel ball was dropped on thermal insulation materials. We discussed about the test results of evaluating method with a constant volume heat source of steel ball by which the fire resistance efficiency of the thermal insulation materials of the several kind of foams was estimated.

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