Recently, a very important problem in the city is electromagnetic interferences caused by buildings. For example, a ghost phenomenon is caused by interaction between incident and reflected TV waves by large buildings. So, there are greater needs to change the finishing materials of the outside wall of large buildings into TV wave absorbers, particularly VHP wave absorbers. Characteristics of radio wave absorption were evaluated by return loss of radio wave every 5MHz from 50MHz to 250MHz. Return loss of each specimen can be calculated from experimental results. The results were as follows. 1) The more ferrite was mixed, the lower the superior frequency. Then return loss at a superior frequency was increased. 2) Under the condition in which reinforcement was placed, the range of radio wave absorption was widened and return loss was increased. So, the characteristic of radio wave absorption was improved by placing reinforcement. 3) Double decker radio wave absorbers composed of different mix ferrite mortars widen the range of radio wave absorption and increase return loss. So, the characteristics of radio wave absorption were also improved by composing different mix ferrite mortars.

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Factors of visual texture which can evaluate the visual impression of ceramic tiles were extracted. Tlie factors were "dignity", "profundity", "visual texture" and "soft'cool". And then, the surface characteristics of ceramic tiles (color, glossiness, surface roughness and others) were measured, and the relations between the cliaracteristics and the factors were discussed.

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Light-weight carbon fiber reinforced concrete (CFRC) is a new building material with light weight and high tensile strength. This study aims at obtaining an optimum mix proportion of the CFRC. The used materials are low-shrinkage cement, high-performance pitch-based carbon fibers, silica sands plus Sirasu balloon and some admixtures. The parameters of the experiments are unit cement content, grain size of silica sand, water-cement ratio, fiber volume fraction, fiber length and mix ratio of silica sand and Sirasu balloon. Fiber dispersion, flow and air content of the fresh CFRC, and specific gravity, compressive and flexural strengths of the hardened one were evaluated.

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It was reported in our previous paper that the aeroelastic instability of a tall square sectioned building occurs in a turbulent flow. This paper describes the characteristics of unsteady aerodynamic forces acting on high-rise buildings with various sections in a turbulent boundary layer. Unsteady aerodynamic forces were severely affected by the side ratio D/B(D:depth, B:breadth) of the buildings. In order to obtain the aerodynamic forces, wind tunnel experiments were conducted by use of the forced oscillation technique. The response curves related to oscillating amplitude and the reduced wind velocity were obtained, which were plotted with the product parameters of the damping ratio and the generalized mass of the buildings. Aeroelastic instability regions for several rectangular sectioned tall buildings were clarified. The aeroelastic instability regions for prisms of D/B≦1 clearly appeared near the resonance wind velocity, while the regions for prisms of D/B≧1 appeared at lower velocities when mass-damping parameter became extremely small.

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Simple empirical formula for fluctuating across-wind and torsional forces of prismatic high rise buildings are examined through wind tunnel test data. Fluctuating wind forces are explained by the turbulence intensity of oncoming flow at the building's height and the function of the side ratio of the building's plan. The differences between the values of wind forces calculated using the empirical formula and the values obtained from wind tunnel tests are within 30 percent. For the response acceleration, the estimated values according to the empirical formula of wind forces proposed by this study are in good agreement with the values obtained from wind tunnel tests and full scale measurements.

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This paper presents the ultimate load capacity of natural rubber bearings. The failure experiments of rubber bearings was carried out in order to clarify the ultimate loading capacity. As the results, the ultimate strength of rubber bearing was over 1500kg/cm^2 in compressive stress. It was found that the ultimate capacity of rubber bearing depended on the amount of the strength and plastic deformation of interlayer steel plates. And also, the experimental results was simulated by Finite Element (FE) analysis. FE analysis show the plastic strain distribution of the steel plates. Based on the experimental results and analysis results, the ultimate load capacity of natural rubber bearing was discussed.

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The object of this study is to develop an understanding of pile foundation response in a liquefiable soil deposit during strong earthquake. Dynamic centrifuge tests were performed under a centrifugal acceleration of 45g on a pile foundation model with a four-pile group embedded in saturated fine sand. Centrifuge test results indicate that pile responses including maximum pile bending moments are greatly affected by soil liquefaction. Pile bending moments induced by the inertial and kinematic interactions during earthquake are investigated. The proposed numerical model which consists of beam elements and nonlinear interaction springs, taking into account the changing effective stress are confirmed to predict effectively the pile foundation responses in liquefied soil. A practical analytical method to evaluate pile maximum bending moments are also verified by comparing with test results.

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The aim of this paper is to investigate the secondary buckling behaviour and mode-coupling of spherical caps under uniformly distributed pressure by using a rotational finite shell element. The post-buckling behaviours after bifurcation point are analyzed exactly by considering multi-mode coupling (with several higer order harmonic wave numbers), and on the way of post-buckling path the positive definiteness of incremental stiffness matrix of uncoupled modes is examined step by step. The secondary buckling point that has zero eigen-value of incremental stiffness matrix and secondary mode are obtained, moreover, the secondary post-buckling path is traced. Beside, with the obtained displacement fields, the total potential energy, strain energy including membrane and bending energy components and Astatic buckling loads are also calculated. From the above energy components, the complicated post-buckling behaviours are examined.

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The method of transversely reinforcing columns by a bellows square steel tube instead of by hoops has been developed to build highrise reinforced concrete buildings in strong earthquake zones. Through compression tests of 1/4 scale columns, we have clarified the confinement effect of the steel tube on elasto-plastic behavior of the columns, and proved the columns have sufficient ductility and bearing capacity even when their compression forces are extremely increased by the vertical shock of an earthquake which may be added to the horizontal shock. In addition, we have proposed design formulas to calculate compression strength and stress-strain relation curves, which are necessary to design the reinforced concrete columns.

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Strain rate effects on strength and deformation performance of reinforced concrete members were numerically investigated by the fiber model analysis under different curvature rate (strain rate) and axial force levels. Relationships between bending moment and curvature were compared with the experimental results under both static and dynamic loading, and the increase ratios of initial stiffness and strength due to higher strain rate were analyzed. Flexural strength could be calculated by the fiber model analysis considering the strain rate effect under both static and dynamic loading. Flexural strength increased and ductility decreased with the increase of the strain rate. The increase ratios of initial stiffness and flexural strength depended on the levels of axial force due to the higher strain rate.

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In this paper seventy-six reinforced concrete pile caps, each with four piles, were tested under vertical load. The variables involved were spacing of piles, arrangement of reinforcement, reinforcement ratio, side length of column and depth of pile cap. In regard to the bending ultimate strength the results of the test were compared with the calculated values according to the provision for the bending in A.I.J. Standard for Structural Calculation of Reinforced Concrete Structures and to the equations proposed by others as well as to that by authors. To conclude the discussions the calculated values according to the authors' equation agreed well with the experimental results.

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In respect to a HT780-Box-Column, cyclic increasing loading tests have applied to its column to SM490-H-Shaped-Beam. The present investigation aims to comprehend the following matters quantitatively. 1. Effect of a bearing ratio of beam against column to hysteresis characteristic of the frame. 2. Effect of an axial force ratio to hysteresis characteristic of the frame, which is including of a case of tensile force applying to the column. 3. Mechanical behavior of the welded portion of electroslag welding and comer welding of the column by a partial penetration welding. Consequently, it is considered that technical data for structural designing HT780-Box-Column can be supplied.

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Lateral buckling of H-shaped beams often represents a limiting factor in their bending performance. So we proposed the new methods to improve a lateral buckling strength of H-shaped beam. In this paper, we propose the structual member to consist of a pair of parallel web plates and flanges having prescribed width on both edges of the web plates. This double-web steel member enables to increase torsional rigidity and lateral buckling strength greatly. We clarified quantitatively the effect of this device to lateral buckling behavior by the results of experiments and theoretical analysis.

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This paper reports axial compression test results of centrifugal concrete rilled steel tubular short column using super high strength concrete. The concrete portion of section has a vacant hole, and the concrete is cast by centrifugal spining method using super high strength concrete. If we are able to use centrifugal cast composite column, we are able to take good points that members weights light, need not require much time for mortar fill into a vacant hole and so on. But there are not many centrifugal cast composite column on researching papers. In this paper, axial compression tests on short column specimens were carried out in order that we may confirm relations between a vacant hole and structual performance. From the results of experiments, we confirm that experimantal maximum strength is higher than superposed strength, even if a section has a vacant hole and we make understand the behavior of centrifugal cast composite column.

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The objective of this paper is to demonstrate the aseismic capacity of concrete-filled tubular members subjected to cyclic axial load. About fifty specimens composed of cold-formed circular tubes and normal concrete were tested to quantify the number of loading cycles and the amount of dissipated energy upto breaking failure after local buckling. The test shows that both the failure cycle and the dissipated energy are fairly increased by filling the tube with concrete. The span of life of concrete-filled tubular member is affected by the diameter-thickness ratio, effective length and amplitude of axial displacement, and is successfully predicted by an estimation method proposed by authors. The dissipated energy upto failure can be also predicted by means of multiplying the number of loading cycles upto failure and the dissipated energy at each loading cycle. The dissipated energy and deformation capacity of concrete-filled tubular member with alternative diameter-thickness ratio and effective length are discussed from the results of test and theoretical estimation.

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The improvement of rigidity of connections and a buckling strength of a tubular truss can be expected by means of filling concrete into the chord member. Further more, it is possible the truss has a stable behavior without in-plane or out-of-plane buckling under cyclic loading. The experiment has been conducted to prove the features. The specimens are beam-columns of Warren trusses, and subjected to a constant axial load and cyclic horizontal load. The test results and theoretical consideration have lead to the condition to certify the stable behavior for the trusses. According to the deformability assessment for steel beam-columns, the stable truss specimens may be evaluated as the top ranks of deformation capacity.

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Axial compression tests on centrifugal concrete filled steel tubular short column specimens were carried out by authors. The concrete is cast by centrifugal spining method using super high strength concrete, and the concrete portion of section has a vacant hole. From the results of experiments, we confirm that experimental maximum strength is higher than superposed strength, even if a section has the vacant hole. Especially, in case of a circular section, concrete filled steel tublular columns has confining effect on filled-concrete by steel tube. In this paper, the evaluation formula of compression strength of consideration for confining effect derived from the results of the axial compression tests. Ultimate compressive strength of concrete filled steel tubular circular columns can be estimated by proposed fomula.

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Nonlinear modulation of quasi-monochromatic, shear wave propagation in 1-dimensional inhomogeneous media was studied. In the analysis, we assumed that the elastic modulus of the inhomogeneous medium varied slowly in the spatial direction. An approach utilizing the soliton theory was proposed to analyze nonlinear wave phenomena in (weakly) inhomogeneous media. The results show that a nonlinear modulated wave in a 1-dimensional finite-elastic medium with a lateral inhomogeneity is governed by the perturbed Schrodinger equation, and that the analytical solution obtained for this equation using modified conservation laws reveals that both the amplitude and angular frequency of an envelope-solitary wave deform progressively in space as a result of media inhomogeneity, and that the scattering envelope-solitary waves are generated by an incident wave propagating in an inhomogeneous region with a monotonically increasing the shear-wave velocity.

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