Glass fiber reinforced mortar is used as a building material because of high strength. However, the effect of reinforcement of glass fiber is influenced easily by the manufacturing method. Moreover, some problems of the glass fiber reinforced mortar are described as follows. (1) Glass fiber reinforced mortar is inferior to other fiber reinforced cement mortar (FRC) in the long term durability. (2) Drying shrinkage rate is large. (3) The mortar is inferior to other FRC in thermal resistance. Authors have studied on fly ash fiber reinforced mortar produced by fusing coal ash. As a result, fly ash fiber reinforced mortar is excellent in the long term durability and heat resistance, drying shrinkage rate is small. Authors proposed the method of improving the performance of glass fiber reinforced mortar. The method is combining fly ash fiber to glass fiber. As a result of the test, it was confirmed that strength of glass fiber reinforced mortar increased, and that durability and thermal resistance improved.

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The influence of thermal properties of high-strength mass concrete using high-fineness flyash was evaluated quantitatively by analytical method and experiment. Inverse analysis method based on heat diffusion equation and sequential analysis method using difference equation was applicable to obtain the numerical value of thermal diffusivity and other constants. The results by two analytical method were well corresponded.By using fly-ash to high-strength mass concrete could be the temperature of concrete lower than that of non fly-ash concrete and compressive strength per calorific value increased.

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A method for estimating crack width at mass concrete wall structure is presented. The method is suitable for the case in which crack width varies along the crack. This paper shows the calculation method and a calculated result. The method is composed of :1) calculation of thermal stress in concrete, 2) calculation of concrete dislocation caused by stress releasing the thermal stress at cracking section, and 3) calculation of effects of re-bar's closing action on the crack width. The proposed method is validated adopting experimental results with a wall structure specimen restrained by a footing. The culculated results using the proposed model are compared with some results computed by the CP Crack Width Method as well as the experimentally observed cracking behavior.

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The applicability of "Impactive Excitation Apparatus" to measurement of floor impact sound generated by walking was investigated. At first, excitation forces applied by walking and the apparatus were investigated. Secondly, the floor impact sounds were measured in actual wood-frame houses. As the results, it was confirmed that the floor impact sound was generated by heel landing, the frequency characteristics of the force of heel landing could be almost substituted by the apparatus, the sound in 250Hz and over hardly affected human sense, and the sounds generated by walking and the apparatus were almost the same between 31.5 and 125Hz.

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Sounds generated from floors by various human actions (called the floor sounds) are recognized as noise. On the other hand, floor sounds may create an atmosphere of Noh play, dancing, sports and so on. The floor sounds are also utilized as a clue as to how blind people perceive an obstacle and a person at a distance. The floor sounds, therefore, is a significant subject in the field of architectural environments. In the present work, the evaluation method of the magnitude of the floor sounds has been studied. As a first step, the relationship between the maximum value (P_<max>) of loads by human actions and A-weighted sound pressure level (dB(A)) was examined under conditions of various combinations of human actions and footwears. Secondly, a impact loading apparatus which synthesizes this relationship was built. Lastly, a sensory test on the magnitude of the floor sounds was carried out for 8 different kinds of floors. From the results of this experiment, it was confirmed that the values of dB(A), produced by the developed apparatus, corresponded to the sensory scale of the floor sounds obtained from the above mentioned test So it can be said conclusively that the evaluation method of the floor sounds using the developed apparatus is representative.

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Densely built structures are analytically investigated focusing on their seismic response and their effects on the wave propagating characteristics in an irregularly layered soil for vertically incident SV wave. Seismic responses of densely built structures are reduced in comparison with those of single structures for both layered and irregularly layered soil mainly due to inertial effect of structures. For horizontally travelling waves like surface waves, effects of plural structures are smaller on the front-end structure than those in the rear side. Densely built structures affect wave propagating characteristics in the neighboring soil by inducing Rayleigh wave due to their inertial effects. In the irregularly layered soil, effects of structures on wave propagation are varied according to the location of the structures.

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Multi-Input-Multi-Output ARX model of Modal Analysis (MIMO-ARX-MA), which is based on the idea that there are common natural frequencies and damping ratios throughout the system, is proposed in this paper. Utilizing response records of multiple observation points together can make the estimation more precisely. In the case of structures whose torsional modes are excited it is necessary to use multiinput model including across direction components. The model proposed here is applied to the earthquake observation records of a triangular planned high-rise building with Hybrid Mass Dampers (HMDs) and the modal parameters of the building, such as natural frequencies, damping ratios, and participation vectors, are estimated, which shows the effectiveness of the proposed model. The effects of HMDs on the modal parameters of the building are also presented.

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The hybrid stress beam-column finite elements, which have been proposed by Dr. Kondoh and based on the assumed stress method, yield no discretizing errors in their elastic and elasto-plastic responses, under the employed beam-column theory, of the member, with any (distributions of axial and flexural rigidity, and stress-strain characteristics) and subjected to any (concentrated and distributed) loads. Then, this approach might be one of the most promising approach to trace and examine the inelastic and collapse behavior of framed structures. In this paper, simple and effective hybrid stress finite element formulation is developed for reinforced concrete (R.C.) framed structures. Based on the Timoshenko's beam-column theory considering the first order shear deformation, resultant stress-generalized strain relations of the R.C. beam-column section, which represent the well-known stiffness degrading characteristics of the R.C. member under the (axial forcing and bending) and their interaction, are formulated. According to the standard procedure shown in Ref.17), the hybrid stress method, wherein employed the Lagrange multiplier method for computational convenience, is unifiedly formulated for the given basic equations and R.C. plane beam-column element is derived. Several numerical tests are performed, and show that the present approach and element have excellent capacity to simulate simply and accurately the more complicate behavior of R.C. framed structures.

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The present paper deals with a development of tendon friction coefficient correlation as a function of loading end load and circumferential angle utilizing measured data. The obtained correlation was incorporated into ABAQUS Ver.5.5 and the tendon tension force distribution change during pressurizalion process of PCCV was analyzed in order to increase the predictive capability of analysis for the 1/4 scale PCCV test facility under construction. The analysis results using the present friction coefficient correlation was compared with the results of analysis using constant friction coefficient, and the effect of the difference on tendon tension force distribution and concrete strain were evaluated.

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As membrane structures can keep their shapes only through in-plane stresses, determination of the objective shapes of membrane structures has to be carried out appropriately by considering physical conditions. Besides, proposal of the cutting pattern of membrane materials is also important in order to avoid unexpected wrinkling or creep deformation which itself can also cause the wrinkling after certain period passed from the initial introduction of prestressing. In this paper, a new approach for determination of the cutting pattern of membrane structures is proposed where the equilibrium state after deformation is simultaneously considered together with the configiration of the cutting pattern as the state of pre-deformation. Utilizing SQP technique for optimization process, the finite element analysis is performed for several examples , where effectiveness of proposed method is clearly shown.

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The present study includes 1) measurements of natural frequencies by ambient vibrations, 2) estimation of the Young's modulus for the used materials based on both dynamic measurements for the minarets and material test of the mortar as well as of the masonry which consists of brick and mortar, 3) estimation of compressive and tensile strength of the mortar, 4) finite element three dimensional elasto-plastic analysis (FEM) in case of dead load for the dome considering the effects of the supporting structure. According to the results of Finite Element analyses, the oval displacement pattern of the base of the dome is in accordance with the actual state of the structure. Comparison of the displacements of two transverse arches, N-Sarch and double arch, seems to give an information that the north to south arch is weaker than the west to east arch.

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Construction process planning of structures have an influence upon the cost and term of the construction. The construction process is often planned by trial and error on the basis of previous experiences. The work is very tough and could not always give an optimal answer. Various difficulties which must be solved also increase when the structure becomes complex and the number of members increases. In this study, our objective is to search for the optimal construction process by a numerical analysis. Genetic Algorithms (GAs) are introduced into the problem of the construction process analysis. The sequence of numbers, which is arranged by the removal order of members, is assumed to represent a chromosome. Members of a structure are removed in order of the chromosome from the completion state. The structure, after removing a member, should be stable. If the criteria are not satisfied, temporary supports are set up on suitable nodes. Consequently, a number of temporary supports or a total sum of reaction forces caused at the temporary supports is considered as an evaluation function of the optimization problem. In this paper, two examples of the construction process analysis are presented, and applicability of GAs to the problem of construction process is discussed.

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A methodology to locate and assess structural damage in reinforced concrete structures from the known modes and natural frequencies of the structures is presented. The damage is defined as the stiffness loss of the structures. Using the perturbation method, the dynamical characteristic changes and the corresponding structural properties such as the stiffness changes are related so that the damaged floors of a structure are located. With the use of the Baruch and Bar Itzhack equations, the perturbed stiffness matrix is adjusted. Comparing the non-damaged stiffness matrix with the obtained perturbed stiffness matrix, the structural elements' damage is located and assessed. The sensitivity matrix that defines the lateral stiffness' sensitivity to the elemental stiffness changes is introduced.

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It is said that so-called shear friction is one of the important mechanisms for shear resistance on the construction joint. By the past studies it was said that coefficient of shear friction depended on only the way of roughing the construction joint. But the authors think that the coefficient of shear friction depends not only on the way of roughing the surface of construction joint but also on the estimated value of surface roughness defined mathematically. Measurement of surface roughness of construction joint and direct shear test of the joint was performed. By the measurement and the loading test it is concluded that the shear force can be predicted by using the estimate value of surface roughness of construction joint if slip dislocation is limited within 1mm, and that the behavior of joint bars and the coefficient of shear friction can be predicted by using the estimate value of surface roughness.

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For the purpose of designing against wind induced fatigue of high rise steel buildings, a series of fatigue tests on welded beam ends at the beam-to-column connections were carried out. Specimens were composed of welded built-up box section steel columns and built-up wide-flange steel beams using 490N/mm^2 class grade of steel. Three types of fabricating methods for beam end joint were examined ; i.e. a field welding type with bolted web and welded flanges , a shop welding type with conventional scallops and another shop welding type without scallop (Non scallop type). Seventeen specimens were prepared for high cycle fatigue tests , low cycle fatigue tests and varying amplitude fatigue tests . S-N diagrams for fatigue design and cumulative damage factors based on Miner's law were obtained and discussed, comparing with the JSSC design recommendation.

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A new type connecting method using vertical stiffeners for WF beam-to-RHS column connections was developed. The vertical sttifners were welded to the both sides of flanges of the beam ends, and the ends of the stiffeners were welded to the corners of RHS columns. The basic statical characteristics of this type connections were already investigated experimentally using T-shaped specimens. In this test series a effective area of the panel zone under severe cyclic loading are investigated experimentally using cruciform specimens. The panel strength ratio Rpp(pMp/Min(ΣbMp, ΣcMp) were designed less than 1. It becomes clear that the maximum strength and plastic deformation capacity of this type connections certified to be enough even if the yeild strength of panel zone was considerably smaller than that of column or beam members. In case every part of this type connection is designed appropriate the welding parts at the corners of RHS column work well. The effective volume of the panel zone are nearly 10% lager than that of usual beam-to-column connections.

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Charpy impact test has been widely used for inspecting fracture toughness of steels in the world since the 1901 invention by French professor Dr. Georges Charpy. However, there has been a doubt and criticism, especially from fracture mechanics, that Charpy properties such as absorbed energy and percent brittle fracture deduced from the impact test may not be correlated with the fracture performance of actual steel members, because of crucial differences between them in terms of loading rate, specimen size, notch configuration, and stress-strain conditions. However, this paper shows that the surfaces as well as processes of the fractures are remarkably correlated between them, which suggests that Charpy test results can be rationally used as good indices for fracture resistance of structural steel members.

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In parti, influence of the confinement effects and residual stresses in steel tube upon inelastic flexural behavior of concrete filled circular steel tubular columns is described. In part2, the influence of diameter to wall thickness ratio are discussed making use of uniform bending tests results. In addition, analytical methods for estimating bending moment-curvature relationships which can predict the experimental results more accurately than the method proposed in parti. Analytical results nearly coincident with experimental results. Therefore, it can be said that these methods are effective to estimate deformation characteristic of concrete filled circular steel tubular columns which are subjected to axial load and bending.

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The purpose of this paper is to make clear the time-dependent effects on the earthquake-resistant capacities of steel and concrete composite frames. The method is a numerical analysis based on the nonlinear finite element method in which the concrete strain is defined as a sum of an elastic-plastic component and time-dependent components (basic creep, free shrinkage and stressinduced shrinkage). The numerical investigation has revealed that 1) the time-dependent effects could be ignored for the steelencased RC beam-column with the L_k/D of about 10 or less (L_k: the effective length, D: the depth of section) and for the CFT beam-column with the L_k/D of about 30 or less; 2) the time-dependent strains cause a rather remarkable reduction of the dissipated energy in the cyclic hysteresis than the reduction of the strength.

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The system used steel reinforced concrete structure walls is convenient for short period construction. In this paper, experimental and analytical studies on seismic behavior of twin raised shear walls consisting the system are described. Coupling beams of twin walls accept severe deformation by strong seismic ground motion. In the test, cyclic horizontal load applied to specimens using normal steel and low yield strength steel to coupling beams. The test results show a good manner of hysteresis energy consumer. And the energy consumed manners of core wall structure were examined by seismic response analysis.

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Structural behaviours of the connections between concrete filled circular tube column and wide flange steel beam have been studied by the beam-and-column space subassemblage tests with experimental variables of connection type and yielding sequences of the consisting parts of space subassemblage specimen. The plastic and ultimate strengths of beam-to-column connections are analysed by the yield line theory, giving good correspondence with the test results. And the plastic strengths of beam-end connection, column-end connection and connection panel are also discussed from the obtained strain measurements of the specimens.

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Dynamic response of two cylindrical shells with a deck which may be used as an offshore structure is dealt with. Taking into account interaction effects between shells and fluid, the harmonic response as well as earthquake response of the system subjected to horizontal excitation at seabed are determined. Earthquake response in time domain is determined by the inverse transforms of multiplication of transfer function and Fourier transform of input wave, and the 1995 Hyogoken-nanbu earthquake wave is adopted as input earthquake motion. When the mass of the deck becomes large, concentrated inertia force of deck is predominant compared to the distributed wave pressure, and the exisitence of the inner fluid has little effect on the dynamic responses different from the case of without a mass of deck. The effects of the shell thickness and deck mass on the earthquake responses of structure and fluid are discussed.

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