Photocatalytic cement-based materials show environment purifying capability and can be used as a NO_x removing paving block, for which we have developed a performance evaluation system with an apparatus capable of supplying an imitated emission air continuously. Studying the relation between NO_x removing performance and test conditions such as NO concentrations, flow rate and relative humidity, an optimum test condition was determined : air gap of 5 mm, NO concentration in the imitated emission air of 1 ppm, flow rate of the imitated emission air of 1.5 to 3.0 liter/mm, relative humidity of the imitated emission air of 10 % or 50 % and UV irradiation of 6 W/m^2.

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Stress-strain relations of prestressing steels under cyclic loading is essential information to predict load-deformation relations of prestressed concrete flexural members. In this paper, the cyclic stress-strain models for PC steels using Menegotto-Pinto expression with variable of strain are proposed based on experimental results of induction heating quenched and tempered PC bars of φ 36mm. The models estimate satisfactorily hysteretic curve of PC strand, stretched and low temperature annealed (blueing) PC bars and induction heating quenched and tempered PC bars of different strength and size under various type of cyclic loading, such as gradual increase strain cyclic loadings, random cyclic loadings etc..

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This paper focuses on the effect of the clang sound from fittings, furniture, tableware, etc., on the perception of floor vibration caused by walking. First, the psychological scale to measure the vibration and sound is constructed by the sensory test. Second, the physical value representing the psychological scale is introduced on the basis of the measurement of the vibration and sound. The relationship between the psychological scale and the physical value reveals that the loudness of the sound affects the perception of the vibration. Finally, the evaluation index of the perception of the vibration influenced by the sound is proposed.

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Wind-induced building behavior has been predicted by wind tunnel tests. However, there are still some differences when compared with field measurement data. Research has been carried out to determine the factors causing these differences. One is variation in non-stationary wind-direction, However, the short-term influence of this factor has not been considered when predicting building behavior, by wind-tunnel tests and conducting wind-resistant design of buildings. This is based on wind-resistant design evaluated for the wind direction that induces the largest wind force or wind-induced responses, and its influence was not large. However, when developing a wind-resistant design that considers the behavior of a building for each wind-direction using meteorological wind data for each wind direction, the influence of non-stationary wind directions cannot always be ignored. This is because the method must predict the behavior of a building for a mean-wind direction that induces a minimiun wind force, etc, even though the actual behavior includes that different wind-direction conditions with wind-direction variations. This report considers the behavior of wind-direction itself with an example of field data. It clarifies the influence of non-stationary wind direction on wind-induced response and wind pressures.

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Authors' group has been conducting full-scale measurements of atmospheric boundary layer wind speeds by doppler sodars. It is expected to obtain the wind speed profile easily by doppler sodars, because the wind speeds at many altitudes can be measured simultaneously. Preceding to the observation, the quality of the data obtained in various measuring conditions was studied, and the optimum measuring condition was shown. In our study, the measurements had been selected on the basis of the wind speed at the reference altitude, and wind speed profile had been evaluated from the averaged values of them. This method was reexamined by the statistical method in this paper. It is conformed that the value of wind speed at the reference altitude is overestimated in this method and suggested that the measurements would rather be selected by the wind speed averaged at whole altitudes. However, it was pointed out that the data collectable rate at higher altitudes reduced as the wind speed became higher. This phenomenon were presumed to be caused by wind-induced noise. In this paper, the effects of wind-induced noise on the data collectable rates and the measurements were also studied. It is confirmed that the effect of wind-induced noise cannot be ignored and the errors in the measurements are significant at higher altitudes.

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Bedrock motions are evaluated using the strong ground motions recorded at the KiK-net stations near the seismic fault of the 2000 Tottori-ken Seibu earthquake (M_j7.3). Analyses of the recorded motions reveals that the soil nonlinearity of soft surface layers plays an important role in site amplification between the two vertical array points during the main shock. Soil properties are adjusted to fit to spectral ratios by using the Genetic Algorithm for both the small aftershocks and the main shock. Input motions are calculated using the estimated soil models. The peak velocities of the bedrock motions are small compared with those in the Kobe City during the 1995 Hyogo-ken Nanbu earthquake (M_j7.3). Strength demand spectra indicate that the destructive power of bedrock motions is also less than those in Kobe, which could be one of the reasons why the structural damage was smaller than expected from the recorded magnitude.

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Stochastic properties of broadband strong motions are investigated using the fractal source model. The model is described by the limited dynamic data reflecting uncertainty and heterogeneity on the fault plane. The soil ground model for source-site path is presented by the theoretical Green's function of the multi-layered half space. The simultaneous simulation test has been tried for the recorded ground motions at some sites in the 1994 Northridge earthquake and the 2000 Western Tottori prefecture earthquake. The average spectra and the duration time of the synthetics correspond well with those of the observed within 20 kilometers from the fault region.

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The effects of base-mat flexibility are discussed on the earthquake-response characteristics of a BWR-type nuclear reactor building. First, the experimental and analytical literature focusing on base mat flexibility is reviewed. Second, earthquake response analysis is conducted, where, as an example, a typical BWR-type nuclear reactor building is idealized by a finite element method. In order to check the effects of base mat flexibility, studies are made under the following two conditions : (1) base-mat flexibility is taken into account, (2) base mat flexibility is not considered. As for soil condition of supporting layer, two conditions--500 m/sec and 1,000 m/sec, respectively--of shear wave velocity are considered. As the results, the reaction stress distribution of the supporting soil and the stress distribution of aseismic walls are compared between models (1) and (2), and the quantitative effects of base mat flexibility on these models are determined.

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In order to examine the local site effects on the strong motion records of the 1999 Chi-Chi earthquake in Taiwan, microtremor measurements are conducted using arrays of sensors at 11 strong motion stations. Shallow shear wave velocity profiles of these stations are estimated based on an inverse analysis of both microtremor dispersion characteristics and H/V spectra. Equivalent linear analysis is conducted using the estimated Vs profiles. It is shown that local soil conditions including nonlinear soil behavior might have had significant effects on the ground motion and performance of buildings during the earthquake.

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A practical analysis model to simulate the cyclic behavior of a linear viscoelastic damper is proposed. It utilizes the classical Kelvin body with adequately specified stiflhess and viscosity. Part 1 paper discusses the modeling method and its accuracy using a single-mass system having the damper, supporting member, and elastic or inelastic frame. The performance of the model is examined by comparing the analytical results with those obtained from the accurate fractional-derivative constitutive rule. Although the frequency-sensitivity of Kelvin body differs considerably from the actual sensitivity, the model is found to produce reasonably accurate results under both sinusoidal and random excitations.

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This paper deals with the system to evaluate the quality of soil-cement column made by deep mixing method. Through the field tests on the several kinds of evaluation methods, main conclusions were summarized as follows. 1) fundamental index to evaluate the quality is the uniaxial compressive strength of the column by random sampling. 2) The electric resistivity tests to evaluate the mixing degree in the unsolidified condition immediately after the construction, the test method to determine the ratio of unmixed soil parts to the total cross section area in the horizontal cutting surface, and also the integrity tests to evaluate the structural soundness of column are useful to make the standard quality based on the strength of core specimens randomly sampled.

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This research looked for solutions in analyzing continuous footing foundation by concluding theoretical problem in concentrated loadings and distributed supports, and establishing analytic model in ideal state. By means of this, practical analytical method concerning continuous footing foundation is developed. 1. Regarding the supporting foundation, assuming that the relative stiffness ratio is infinity, establishing the balancing model of a single continuous footing, theoretical formula for the distribution of bearing pressure and stress produced on the foundation beam is presented. 2. For continuous footing, as a statically determinate structure disregarding the stiffness of the torsion of orthogonal member, the shifting produced by torsion, and the characteristic of distribution of bearing pressure is clarified. 3. Considering torsion, an analytical method of continuous footing as a statically determinate structure is proposed. 4. By testing through samples, theoretical accuracy of the analytic method is verified.

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Parallel finite element stress analyses of Pantheon are conducted on a PC cluster. The authors are involved in a project in which a parallel computational mechanics system including pre-, main-, and post-processing modules based on the domain decomposition are being developed. Geometry models are first created by using a 3D CAD, and then fine meshes with tetrahedral solid elements are automatically generated. The static stress analysis with a mesh of 18 millions DOFs, and elastic-plastic stress analysis and seismic response analysis with meshes of several million DOFs are conducted. The results are visualized by the parallel post-processing module. Not only the effectiveness but also some problems in the large-scale analyses of architectural structures are described as concluding remarks.

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Dynamic and static loading tests of reinforced concrete member (RC member) have been carried out and the loading rate effect on the restoring force of it is obtained from the differences between the dynamic and static test results. On the basis of the test results the loading rate effect equation which is expressed by the plastic deformation and the accumulated plastic deformation of member is proposed. The dynamic restoring force model of RC member under seismic load is also derived by applying the loading rate effect equation to the static restoring force model. It is ascertained that the presented dynamic restoring force model is useful by comparing it with the dynamic loading test results.

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In order to develop a method for analyzing shear behavior in reinforced concrete, this study derives a constitutive equation for stress transfer upon cracked surfaces in light-weight and normal-weight concrete. The complex asperity of cracked surfaces is quantitatively determined by gathering high-precision data. The geometrical characteristics of cracked surfaces can be represented as the product of the contact angle probability density and the effective ratio of contact roughness, described in a previous paper by the same authors. In this paper, the authors discuss the relationship between contact compressive stress and strain in a direction perpendicular to the contact surface, proposing a constitutive equation for stress transfer upon cracked surfaces. The proposed constitutive equation can be used to predict a series of stress transfers upon cracked surfaces in light-weight and normal-weight concrete.

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Various dynamic structural computer programs for seismic performance evaluation, which are used for practical structural design, have their own characteristics in structural modeling and structural regulations. Through the structural design process the designers also do various kinds of engineering judgments. We, AIJ Kinki branch, have investigated the difference of analytical results obtained from various RC structural dynamic computer programs for seismic performance evaluation. These analyses were executed by 12 companies in which 8 are construction companies, 2 are design companies and the other 2 are program developers. This paper presents the variation of calculated dynamic responses of a lumped mass model of 7-story reinforced concrete building, which includes bearing walls in longitudinal direction and no wall in lateral direction. The main difference of the results was caused by the difference of story shear force and story translation relationship obtained from the static computer programs.

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The authors have modified the Space Truss Analogy method advocated by M. P. Collins to analyze torsional behavior of reinforced rectangular members. The experimental results are compared with the analytical results from the modified method and with the estimated results from the formulae of ACI Code 318-'89 and -'95. The correlation between analytical results of crack and maximum torsional moments and the experimental results was good. The crack and maximum torsional moments estimated from the ACI Code '95 also coincide with the experimental results. The moments estimated from ACI Code '89 do not coincide with the experimental results. The formulae of ACI Code 318-'95 can be refered to AIJ Standard for structural calculation of reinforced concrete structures.

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A new seismic or emergency retrofit method, in which aramid fiber belts are prestressed and used as external transverse reinforcement, is proposed in this paper. Five shear critical columns with shear span to depth ratio of 1.5 and poor transverse reinforcement, were retrofitted and tested under reversed cyclic lateral forces and constant axial load, simultaneously. The test results indicated that the proposed method could be a highly effective retrofit technique for RC columns with inadequate shear resistance or poor bond strength. Moreover, the experimental results for a retrofitted earthquake-damaged column showed that the proposed method, as an emergency retrofit technique, could restore the lateral strength of column. Finally, the calculated shear and bond strength based on AIJ design guidelines' equations and flexural strength by use of simplified equation and a fiber model were found in good agreement with experimental results.

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Three-dimensional non-linear restoring force characteristics of R/C columns are formulated based on the plastic theory. Loading surface, kinematic hardening rule, and method to calculate elastic rigidity and elastic region are proposed in this paper. Loading surface and kinematic hardening rule that can be used for concrete sections are obtained by examining a rectangle section model. The material of the section model is rigid-perfectly plastic but cannot transfer tensile stress. Yield surface in M_x-M_y-N space that is extended from M-N interaction curve based on the additional theory is used to calculate elastic rigidity matrix that estimate elastic components during elastic-plastic condition of R/C columns. The analysis model consists of the loading surface, kinematic hardening rule, and elastic rigidity proposed. It can be said from comparison between test and numerical results of a R/C column that the model can macroscopically describe restoring force characteristics of the column subjected to varying axial force and cyclic shear-bending loading.

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Shear transfer across a definite interface must frequently be considered in the design of precast concrete connections. As the following various resistances in the effecting shear transfer strength are given : (1) Dowel action of joint steel bars, (2) Shear-key resistance, (3) Friction with axial force, (4) Adherence on the concrete surface. The purpose of this paper is to reveal the compound effects of the various resistance elements. Basic experiments on the interface shear transfer at the precast concrete connections ware carried out. Fifteen panel type specimens with the same dimensions were tested. As a conclusion, the relation of the shear transfer mechanism and shear displacement behaviour in concrete connection is clarified. And the evaluation equation of the shear transfer strength with consideration to the shear displacement conformity is proposed.

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In this paper, tensile tests were carried out to investigate strength of oblique crossing joint by fillet weld. The results of macro tests explain that inadequate penetration of fillet weld occurred at the acute side of welds because of the small oblique angle. The results of tensile tests explain as follows ; 1) The failure of joint often occurred at the obtuse side of welds. 2) Failure angle of welds disagrees with the angles of those minimum throat thicknesses. 3) The strength of fillet weld decreases with smaller oblique angle.

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In this report we discussed the manner to analyze the elasto-plastic mechanical behavior of anchor bolts and the base-plate constituting an exposure fixed-type column base. Specially, it is important to make clear the relation between the deflection of the base-plate and tensile force of anchor bolts, which is caused by working the moment to the column base. We investigate the real behavior of these elements through experiment subjected only bending moment, using real size steel column base specimens. After that taking advantage of the investigated results we proposed a useful analytical methods to predict elasto-plastic behavior as to strength and rigidity of the column-base of this type.

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1.はじめに 著者らは、文献[3]において、鋼構造ラーメン骨組に対する終局地震荷重効果を、崩壊メカニズム数を重要なもののみに低減した降伏多面体モデルを用いた応答解析で評価する手法を提案した。そこでは荷重効果は、大局的な応答変位履歴ないし各崩壊機構形の塑性変形履歴の形で与えられる。本稿では、(1)この荷重効果に対して、鋼構造ラーメン骨組の性能が受容できるかどうかの判定を行う手法を示し、(2)鋼構造ラーメン部材の耐力劣化に関連した性能判定を、統一的に表現する累積損傷クライテリア、について提案する。2.簡略化応答解析による要求部材塑性変形性能 (1)考慮する崩壊機構数を低減した簡略化応答解析[3]の概要 予備解析として弾性地震荷重効果の静的水平荷重モデルとして、古典的規準モードの荷重基底ベクトルにランダムモード乗数を乗じて線形結合した荷重モデルを仮定する。モード乗数は零平均とし、標準偏差は、各次有効質量と設計用加速度応答スペクトル値の積に比例させる。骨組の崩壊機構形の信頼性指標値を評価して小さいものを選択し、また相関の大きな複数の崩壊機構形は統合して、骨組の塑性崩壊に対する安全領域を降伏多面体モデルで近似する。安全領域の内部では弾性と仮定し、塑性変位増分の法線則によって応答解析を行う。(2)要求部材塑性変形性能の評価例 複数の崩壊機構形毎に塑性変形履歴が算定されるが、その塑性変形履歴から、適合式により崩壊機構形に属する塑性ヒンジの塑性回転角履歴を求める。塑性ヒンジが複数の崩壊機構形に属する場合は、それぞれの塑性回転角履歴の単純和を塑性ヒンジの応答履歴とみなす。文献[3]で例題とした6層2スパン骨組に4種の実地震波形を入力した結果、比較的大きな塑性変形を被る塑性ヒンジの累積塑性変形角ならびに最大塑性変形角について、簡略化応答解析結果(縦軸)と、塑性ヒンジ法による部材レベル弾塑性応答解析結果(横軸)とを図7に対照している。簡略化応答解析で概ね安全側に評価できることが分かる。3.スケルトン移動型履歴モデルを利用した受容判定 上記の簡略化応答解析では、一般化された完全弾塑性挙動が仮定されているので、耐力劣化が顕著でない範囲の応答予測結果が得られる。その応答履歴を、耐力劣化現象も含むスケルトン移動型履歴モデルに適用して、耐力劣化が顕著になるかについての受容判定を行う。(1)スケルトン移動型モデルの概要 歪み硬化、局部座屈・横座屈等の不安定現象による耐力劣化など、塑性抵抗力の変化を含む履歴モデルとして、第2著者の提案になるスケルトン移動型履歴モデル[6][7][8]を利用する。図8に履歴則を示しているが、1)正側、負側にスケルトン曲線を仮定し、それぞれに目標点を置く。初期位置としては塑性化開始点に置く。2)載荷点が、一方のスケルトン曲線の塑性部分をたどると同時に、その上の目標点を載荷点と一緒に移動する。また塑性移動量のΨ倍(シフト係数)だけ、逆側のスケルトン曲線を同じ方向に移動する。3)一方のスケルトンから除荷した直後は、弾性除荷とするが、逆側のスケルトン上の目標点に向かう場合は、除荷点と目標点とを結ぶ軟化曲線上をたどる。単調載荷曲線に適合するようにスケルトン曲線を定め、適切なシフト係数を仮定すると、耐力劣化の生じる鉄骨ラーメン部材の履歴曲線や地震応答性状を追跡できる。(図9、図10)スケルトン履歴型モデルを用いて部材レベルの応答解析を行えば、要求性能と性能の受容判定を同時に行えるが(図1)、本稿では要求性能については完全弾塑性モデル、受容判定にのみスケルトン移動型モデルを用いる。(図2) (2)耐力劣化の発生しない繰返し変位振幅 スケルトン移動型履歴モデルでは、塑性抵抗力の変化は、各方向のスケルトン曲線上で経験する塑性変形の総和(スケルトン累積塑性変形)に依存することになるので、耐力劣化に関わる性能判定は、スケルトン累積塑性変形を参照する。また塑性変位一定振幅の繰返し載荷を行った場合、Nサイクル時のスケルトン累積塑性変形は(1)式で与えられ、0<Ψ<1のとき、Nを無限大の極限にすると(1)式は(2)式に収斂する。すなわち、十分小さな振幅で繰り返すと何度繰り返しても、スケルトン累積塑性変形はある値以上に進行しない。すなわちスケルトン移動型履歴則は、耐力劣化の発生しない限界変位振幅が存在することを内包している。宇田川らはH形断面部材について繰返し載荷実験を行い、図13のような限界振幅を観察している[10]。逆に、実験的に耐力劣化の生じない限界振幅ならびに単調載荷時の耐力劣化開始変位が測定されていれば、(3)式によってシフト係数Ψを同定することができる。宇田川らの実験[10][11]から同定したΨの値を表5、図15に示しているが、シフト係数Ψ=0.5から0.8程度の値となる。(3)Manson-Coffin則との対応 低サイクル疲労破壊の場合に用いられる古典的な累積損傷則として、Manson-Coffin則がある。(4)-(6)式、図16において、本稿におけるスケルトン移動型履歴モデルに基づく累積損傷則との比較を行っているが、ある塑性歪振幅、あるサイクル数の範囲内では、シフト係数を例えば0.8程度に設定して塑性歪履歴に適用すれば、式(4)のManson-Coffin則と同等の累積損傷則を表現できるので、この種の低サイクル疲労のシミュレーションにも利用できる。しかしながら、1)Manson-Coffin則の形からは、前項のような破壊の生じない塑性歪振幅は導出することはできないこと、2)本稿で用いているような大局的応答の塑性履歴は、低サイクル疲労亀裂の成長に関連するような局所の塑性歪履歴を反映していないこと、に留意すべきである。(4)その他の簡略化された損傷規範 1)Ψ=0とすると、過去に経験した最大応答変位を超過しない限り、繰返し塑性変形を受けてもスケルトン累積塑性変形が進行しない。すなわち、最大応答変位と単調変形能力の比較による性能判定になる。2)Ψ=1とすると、ある方向の繰り返し塑性変形増分が全てその方向のスケルトン累積塑性変形に算入されることになり、通常の累積塑性変形と単調変形能力の比較による加藤-秋山型の安全側に簡略化した性能判定になる。4.簡略化応答解析による性能評価例 2.の簡略化応答解析例で算定された塑性回転角履歴に対して、Ψ=1ならびに0.8を用いて算定したスケルトン累積塑性回転角を表6に示しているが、ここで用いた地震応答履歴は繰返し回数が比較的少なかったため、両者に大きな差は認められなかった。5.まとめ 鋼構造ラーメン骨組の崩壊機構数を重要なもののみに低減した降伏多面体モデルを用いて簡略化応答解析を行い、得られた崩壊機構毎の塑性変形履歴を、塑性ヒンジの塑性回転角履歴に変換する手法を示し、6層2スパン骨組の応答解析例によりその適用性を調べた。また得られた塑性回転角履歴をスケルトン移動型の履歴モデルに適用してスケルトン累積塑性変形を評価し、単調変形能力と比較することにより部材耐力劣化に関わる受容判定を簡便に行う手法を示した。

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The authors have previously proposed a non-linear load deformation relation model for predicting the elasto plastic behavior of the panel zone of steel beam to concrete-filled square steel tubular column connections. This model is based on superposition of the tri-linear relation for the steel tube and the infill concrete. This research verifies the analytical model by comparison with experiment results of the various experimental parameters. The analytical results agree approximately with the experimental results up to a large shear deformation. Moreover, a simple model based on a tri-linear relation is proposed for the panel zone, which produces the same result as the non-linear relation model by comparison with the experiment result.

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The authors have previously proposed a non-linear load deformation relation model for predicting the elasto plastic behavior of the panel zone of steel beam to concrete-filled circular tubular steel column connections. This model is based on the superposition of the tri-linear relation for the steel tube and the infill concrete. This research verifies the analytical model by comparison with experimental result of the various experiment parameters. The analytical results agree approximately with the experimental results up to a large shear deformation. Moreover, a simple model based on a tri-linear relation is proposed for the panel zone, which produces the same result as the non-linear relation model by comparison with the experiment result.

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