The effects of slag content and polymer-binder ratio on the strength properties of autoclaved SBR-modified concretes using ground granulated blast-furnace slag (slag) and a styrene-butadiene rubber (SBR) latex are examined. As a result, the compressive and tensile strengths of the autoclaved SBR-modified concretes using slag reach a maximum at a slag content of 40%, and increase with increasing polymer-binder ratio. In particular, the autoclaved SBR-modified concretes with a slag content of 40% provide about three times higher tensile strength than unmodified concretes. Such strength development is attributed to the improved bond between cement hydrates and aggregates because of the incorporation of SBR latex.

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The noise of the vibrating table at a concrete plant disturbs the workers at the plant and the people who live around it. This paper proposes a new compaction method that is named as the horizontal vibration method. The new method has the ability to replace the vibrating table method. In this method, the mold is shaken in the horizontal direction with the low frequency and large amplitude. This paper presents the relationships between the amplitudes, frequencies, compaction time of the horizontal vibration and the resulting compaction, then describes the effect of horizontal vibration on the concrete. The results of this study indicate that the good compaction can be attained with the horizontal vibration method.

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To solve the short of skilled welders question stemming from the coming Japanese aging society, it is greatly expected to actualize the automatic stick movement of reinforcing rod weld joint. In the case of existing automatic device, great attention and case always paid to the operability,durability and transportability of the device under the current situation of complicated weld work. To overcome difficulties, we developed three axes movement method for the work. Various experiments were carried out to improve weld quality of the new method. As a result, the same quality as equal as that of hand weld is secured.

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In this study, experimental investigations were conducted regarding fundamental properties of binder made of sludge cake and blast furnace slag. The following items were investigated. 1) An influence of mixing ratios of sludge cake on the development of compressive strength of the binder. 2) An influence of stock periods of sludge cake after dehydrating on the development of compressive strength of the binder. 3) An effect of Fiber reinforcement on the mechanical properties of the sludge binder. 4) A theory for estimating the compressive strength of the sludge binder. 5) A method for promoting the development of compressive strength of the sludge binder.

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With an aim to predict the unsteady behavior of separated flows and the vortex structures around a building, DNS(Direct Numerical Simulation) and LES(Large Eddy Simulation) using the interpolation method that satisfies conservative properties in generalized coordinate system is applied to the comlex flows around a circular cylinder. Firstly, in order to clarify the accuracy of the interpolation method, it is shown that the computed aerodynamic quantities at low Reynolds numbers(Re) are in good agreement with the previous experimental results. Especially, we focus on flows around a circular cylinder at Re=200, 270 by DNS and investigate two different modes of 3D shedding in the cylinder wake transition. Secondly, the subgrid scale modeling for LES of turbulent flows is incorporated with the 3D numerical scheme using the interpolation method. Its applicability to the complex flows around a circular cylinder at Re=1,000 is discussed in detail.

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For useful estimation of ground snow load, the authors have built the snow layer model using data of daily precipitation, daily mean and daily minimum air temperature. Although the catch ratio of solid precipitation is important for estimating the snow load on the ground, the calculation results using the catch ratio proposed by Ohno et al. was not sufficient for some observation points. Therefore the authors proposed the new equation for the catch ratio using daily mean temperature. The results with newly proposed catch ratio was sufficient for every observation points.

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Damping coefficient of the oil damper installed in the buildings was set to the optimal value which the damping factor became the maximum value. First, the occurred damping force by the stationary response was formulated. Based on the results, the damping force by the seismic response was presumed. Next, the limitation ratio of the damping force not to spoil the response reduction effect was recommended for the stationary and seismic response. Also, the validity of the presumption and the recommendation were verified by the seismic response analysis using the building models. Finally, because of the formula of the required damping force was proposed, the useful method on the structural design to decide the oid damper volume was presented.

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The effective stresses on the asperities and backgrounds of the faults should be evaluated in the strong motion prediction for future earthquakes. First, short-period source spectra were inferred from variable-slip rupture models for 12 earthquakes of Mw 5.6 to 7.2 in lands and for 6 large earthquakes of M_W 7.2 to 8.1 in subduction zones. Then, the slip amounts and effective stresses on the asperities and backgrounds were evaluated based on the short-period source spectra inferred in this paper. Here, the statistics of the variable-slip rupture models were adopted that described the ratios of the areas, slip amounts, and effective stresses on the asperities to those on the entire fault. Finally, modeling of faults were presented for two types of destructive earthquakes of M_W 7.3 in lands and of M_W 8.3 in subduction zones with the effective stresses 126 bars and 83 bars, respectively, on the asperities.

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In this paper, the authors considered the analytical method and the distribution of friction of sliding seismic isolation system with friction for the lightweight houses. Now, previous analytical method as one direction was extended to new method that vibrates two directions at the same time. And, the authors verified the analytical method by directly comparing experimental values with analytical values. An optimum coefficient of friction and effects of sliding seismic isolation for much kind of seismic waves was predicted by simulating the distribution of various coefficients of friction.

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Numerical analyses are carried out to evaluate the effects of the soil nonlinearity of diluvial deposit and deep sediment on the earthquake responses of surface ground and buildings. The site studied here is a reclaimed ground in Kobe Port, and input motion is an inverted bedrock motion during the 1995 Hyogoken-nambu earthquake. Effective stress analyses of ground models and nonlinear analyses of building models show that the difference of modeling about soil nonlinearity much affect the earthquake responses of ground and building models. These results suggest that the depth of engineering bedrock is a significant element in seismic design. In addition, it is important to consider properly the soil nonlinearity of deep ground to predict damage level or to study the cause of actual damage.

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A method for evaluating the economic losses caused by building damage was studied as one of a series of methods employed to evaluate the monetary costs needed for earthquake victims to rebuild their lives. Residential earthquake insurance claims payments were used as indicators for evaluating economic losses from building damage. Vulnerability functions for buildings were prepared for individual degree of damage caused to the buildings, based on data on the insurance claims payments made in the aftermath of the 1995 Hyogo-ken Nanbu Earthquake. In order to validate the vulnerability functions, the insurance claims payments for buildings in the Hyogo-ken Nanbu Earthquake were calculated; the calculated values were compatible to the amount actually paid.

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In order to comprehend dynamic characteristics of adjacent 3-story RC building and 6-story Steel Reinforced Concrete (SRC) building, earthquake observation, forced vibration experiment and microtremor observation were carried out. The following results are obtained. The adjacent buildings are affected by both of Soil-Structure Interaction (SSI) and Dynamic Cross Interaction (DCI). The input loss of earthquake motion is not clear for both of adjacent buildings. The dynamic characteristics of smaller building are much affected by larger one. DCI effects are shown to be transmitted by soil, including rocking and torsion of buildings.

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This paper reveals several factors influencing the shape and the quality of the bottom concrete in cast-in-place concrete piles by model tests. A steel cylinder filled with a slurry was used to model a borehole where sediment so called "slime" settles on the bottom of the cylinder. Concrete placing follows by a tremie as practical manner. Through the experiment following conclusions were obtained, l) The shape of the concrete at pile bottom is deeply related to the soil type and stiffness of the sediment. 2) The effect of the thickness of the sediment on the compressive strength of the concrete at pile bottom is very small. 3) The stiffness of the sediment becomes small in the cases when the viscosity of the slurry is high. 4) The increasing stiffness of the sediment with depth is obtained by a sediment penetration test.

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A method is presented for determination of cutting pattern of membrane structures considering viscoelasticity of material. Constitutive law is first proposed to represent viscoelastic behavior of material in the range around of the target stress level. The constitutive parameters are obtained from the bi-axial tests of membrane sheets. Then the elastic stress-strain relation is obtained from the proposed law, at the final state where relaxation behavior is terminated. The initial stress immediately after construction is found using the stress-strain relation at the terminal state. The effectiveness of the proposed method is discussed in the example of an HP-type membrane.

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The failure modes and ductility of RC columns retrofitted by aramid fiber reinforced polymer sheets are discussed in this paper. In order to clarify the influence of fiber quantity and chamfering radius on the ductility of retrofitted columns, both cyclic loading test on 9 column specimens and nonlinear 3-dimensional FEM analysis were carried out. The followings are mainly concluded out of this investigation. 1) When existing RC columns are retrofitted so as to be more than 1.0 for both shear and bond capacity margins according to the AIJ design guidelines, they will get sufficient ductility. 2) The increase of the chamfering radius is effective for the transverse confinement together with the increase of the fiber reinforcement quantity.

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This paper presents two design equations for the deformation capacity of exterior reinforced concrete columns subjected to cyclic lateral loading and a varying axial load. These two are determined by the strain softening on the skeleton curve of concrete under monotonically increasing loading and the hysteretic characteristics of concrete under cyclic loading, respectively, as well as the two design equations for the deformation capacity of columns under a constant axial load which have been proposed in the authors' previous paper. The smaller one given by the two design equations defines the deformation capacity.

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Static nonlinear analysis and dynamic analysis is executed in structural design as slight precise method for seismic performance evaluation. For these analysis computer programs are used. Because the computer programs are developed by various construction companies, structural design companies or computer programming developers with their own concepts, the analyzed results may have variation even if a same structure is analyzed. The purpose of this study is to investigate how large the variation is and what the main causes of the variation are. The nonlinear static analysis about a 7-story reinforced concrete frame structure is executed by 12 companies using their usually used computer programs for structural design. The difference of their computer programs, the resultant variation of lateral story shear force and flexural strength of structural members are discussed.

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In this paper, the post-buckling strength of thin-plates are studied. The plates are supossed to be subjected to (i)compression, (ii)in-plane bending, (iii)in-plane shear stress states. A simple design formula in terms of effective compressive width is proposed for the post-buckling strength. The applicability of the proposed formula is examined by FEM analyses.

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A simple proposal for ultimate seismic demand evaluation of multi-degree-of-freedom moment resisting steel frames is developed from limit analysis and first order reliability method (FORM). First, a procedure is proposed for 'vibration mode-failure mode' integrated analysis, wherein the restoring force characteristics are represented by a global convex yield polyhedron model, instead of a set of member hysteresis based models usually adopted in the inelastic structural analysis. Then, FORM is extended to seismic design in the form of 'random pushover analysis', to choose an appropriate number of failure modes to be considered in the vibration mode-failure mode analysis. Random pushover shows a positive correlation with the deterministic analytical procedures and can be further used to determine the lateral load patterns for pushover by the nonlinear static procedures. A six-storey two-bay frame is taken for case study and is analysed by the proposed methods for three ground motions and an impulse. By comparing the results with the member-hysteresis based analytical procedures, this study indicates that the proposed simple methods can serve as a good tool for seismic demand evaluation for practical purposes.

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A formula for evaluating an effective length factor of column in unbrased symmetrical frame is proposed. An equation for an effective length of column is obtained by using the energy method, and it is modified to compensate for unsafe estimation. It is shown that the effective length obtained by proposed formula agrees well with the correct value. Moreover, an example is given and compared to precise results obtained by "Guide to the Plastic Design of Steel Structures ".

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