This study outlines the development of the world's first concrete floor slab finishing robot, and reviews and evaluates its applicability at construction sites. To make it be of much practical use, we developed these robots in stages, beginning with a prototype, then "Mark 2", and finally producing an improved model. The final model, an improved "Mark 2" was used at construction sites and its performance was evaluated. The results were in near agreement to the goals set out prior to development. New robots based on the final model have been manufactured and commercialized now. These robots are being used at various construction sites.

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This study presents the relative evaluation method on floors from a viewpoint of slipperiness at using walking sticks. First, in order to clarify the tendency of loads on floor surfaces affected by walking sticks, we measured horizontal and vertical loads by them. Then, to make evaluation scales of slipperiness, we carried out sensory tests at using walking sticks. Next, we proved that slip resistances which were composed C.S.R corresponded to evaluation scales. As a result, the method to evaluate the slipperiness of floors at using walking sticks exemplified as the method to measure the slip resistance and evaluation indices.

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The aim of this study is to present the relative evaluation method on unevenness of floor and road surfaces from the viewpoint of stability of footing in case of limiting locations stepped on uneveuness. First, to make the psychological scales about stability, sensory tests were taken place. Next, the method to measure the physical value of unevenness which corresponded to the psychological scales was developed. Finally, the evaluation indexes which were composed of the psychological scales and the physical values, and the method to measure the physical values were presented as the relative evaluation method.

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Correlation of basic random variables is of importance in structural reliability analysis. This paper presents an efficient probability analysis method for the sum of exponentially correlated non-normal random variables. Expressing the correlated basic variables in terms of two sets of uncorrelated random variables, the characteristic function of their sum can be estimated approximately by the characteristic functions of the correlated basic variables. The probability density function of the sum is obtained using Fast Fourier Transform. The accuracy and applicability of the method are investigated based on the estimation error of the cumulant and using numerical examples.

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A design method of variable gain feedback controller for a building-AMD system is proposed. A constraint on AMD system such as control force or stroke of a mass damper can be considered individually in this design method. The method consists of two design stages. In the first stage one parameter a is defined which corresponds to the performance of AMD system with respect to the constraint and the variable feedback gain is evaluated as a function of parameter α. In the second stage the parameter a is changed continuously by on-line computation so as to keep the response of the AMD system within the constraint. It is shown through numerical examples that this method effectively adjusts the response of AMD system such as control force or stroke of a mass damper against the variety of intensity levels of external excitation. The performance and the application range of the AMD system is thereby improved remarkably compared to those achieved by ordinary constant gain feedback control.

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It has been revealed by the symmetry limit analysis and the equilibrium path bifurcation analysis of multistory multibay weak-beam planar frames that there exists an unknown type of collapse behavior characterized by the growth of a bow-shaped overall deflection mode in the frame. A numerical response analysis, performed later, has shown that the bow-shaped overall deflection mode can also appear and grow in the frames subjected to cyclic ground motion. In that study, however, simple frame model was considered, so actual dynamic collapse behavior has not been clarified. In this paper, accurate dynamic response analyses are carried out for more realistic frame models which have a mass at every floor. It will be shown that there exists deformation concentration phenomena in the process of dynamic collapse, which is characterized by the growth of bow-shaped deflection mode and the concentration of this mode in the restricted lower region. A theoretical method will be proposed for predicting the height of the deformation concentration region.

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Seismic response of multistory frames having elastic-plastic-brittle columns was numerically investigated. The columns were assumed to lose their restoring forces thoroughly after some plastic excursions. The plastic deformation capacity limited by such brittle fracture was regarded random. It was observed that the fracture of the brittlest column in a particular story causes consequent fracture of the remaining columns in the same story, resulting in dynamic progressive failure of the story like the pancake-type crash. Such fracture instability is enhanced by the randomness involved in the column-ductility. In order to make the safety of such brittle frames equivalent to the ordinary elastic-plastic frames, overstrength or overductility must be assigned to the columns according to the damage concentration escalated by brittle fracture.

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This paper proposes one method to analyze the vibration of friction systems with reasonable handling for discontinuities of friction force. That method is applied for multi-degrees of freedom systems and sliding isolation systems. In the case of severe earthquake, it is necessary to consider the pressure variation on the friction surface and contact problems including collision or separation. For those problems, one method is explained in this paper to proceed in numerical integration using stick-slip-contact condition. Several numerical simulations are carried out in the following order. At first, for single mass system subjected to horizontal and vertical earthquake, the effect of frictional sliding isolation is examined. Next, for two-dimensional base isolated structure, the effect of pressure variation and contact problems are investigated. Last, for three-dimensional base isolated structure subjected to tri-axial earthquake, seismic response behavior is shown as an example of analysis for multi-degrees of freedom system.

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This paper described the soil resistance supporting the diaphragm walls with various shaped cross sections such as T and + for cantilever earth retaining. The authors showed the measured behavior of this type earth retaining walls under excavation. We proposed a method for estimating soil resistance supporting this type walls and clarified the influence of the cross sectional shape of the wall on the soil resistance. We applied this method to the simulation analysis concerning the behavior of the above earth retaining walls under excavation, and confirmed the validity of this method.

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A calculation formula for prestressing force distribution during tensioning at both ends was proposed in this paper taking account of the formula proposed in the Part 1 of this study as well as the following findings from the recent experimental studies : 1) The prestressing force at the mid-span of a tendon given by stressing at one end increases with further stressing at the other end which was previously a passive end. 2) The friction coefficient between tendon and duct varies as the direction of stressing changes. Therefore the distribution of the prestressing force depends on which end of the tendon is chosen to be the first active end. The elongation of tendons in a PCCV was found to be more accurately estimated by the proposed calculation method than by that in the present design practice.

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Multispan gable frame structures with suitable beams and braces on the roof show a significant cubic folded plate effect that reduces the displacements and the stress resultants of each gable frame. The basic equations of the structures are derived by introducing an orthotropic plate theory to the roof plate. Then, restrictions on the displacements of the roof plate enable to transform the gable frame structures with columns and end walls into Timoshenko beam theories. A case where the gable frame structures behave under asymmetric displacements with respect to the roof ridge is shown to demonstrate the procedure that gives precise solutions.

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It is often hard to obtain analytical solutions of boundary value problems of shells. Introducing some approximations into the basic equations may allow us to get analytical solutions that clarify global behaviors of boundary value problems. Instead of an analytical procedure, we examine Runge-Kutta method as a numerical solution of simultaneous ordinary differential equations to solve the problems. Applying the numerical method to typical examples of cylindrical water tanks, cylindrical roofs and a spherical shell, we analyze them and examine accuracy of their solutions that are depicted in Tables.

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There have been many studies concerning the various factors affecting shear failure and thus the understanding and kowledge of the shear transfer mechanisms in reinforced concrete (R/C) members have progressed significantly. However, the question of shear failure and the effects of the various factors are far from being settled. This paper reviews the shear design equations proposed in Japan to evaluate the shear strength of R/C members and compares the contribution quantitatively of the principal factors by means of a numerical example. The calculated values by these equations are compared to a number of experimental results which have been performed in Japan recently by means of statistical and probabilistic approaches.

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Uniaxial compression tests of confined concrete consisting of concrete with strength ranging 30 to 120MPa, and spiral reinforcement with strength in the range of 400 to 1200MPa were conducted. The test results indicate that confined concrete composed of high strength materials inclines to show lower improvement of mechanical characteristics such as compressive strength because of non-yielding of lateral reinforcement due to small lateral strain of high strength concrete and large strain at yielding of high strength reinforcing bars. Equations for predicting extensively strength and deformation characteristics of spirally confined concrete are derived by modifying the previous equations for confined concrete with concrete and circular reinforcement having ordinary strength.

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The purpose of this paper is to clarify the local buckling and the post local buckling behavior of H-section steel columns owing to the interaction of plate elements, from the view point of the width-thickness ratio and the area ratio of the plate elements. A series of stub-columns test is performed. The specimens are composed of thin plate and thick plate elements. The main parameters are the width-thickness ratio and the area ratio of plate elements. Following this test results, the evaluation formulas of the deformation capacity of H-section steel stub-columns considering the area ratio are proposed, and the evaluation formulas are compared with the test results.

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In order to estimate easily the elasto-plastic behavior of a certain story of a multi-span multi-story unbraced steel frame, an approximate horizontal load-deflection relationship of "a fundamental subassemblage" is proposed using the stability limit strength formula obtained by authors previously. This relationship is composed of four straight lines; 1. Elastic line, 2. Yield line, 3. Stability limit strength line and 4. Mechanism line. Applying the relationship to multi-span one-story subassemblages, it is verified that the approximate stability limit strengths and deformations agree well the results of precise numerical analysis, inspite of the simplicity of the proposed method.

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The purpose of this study is to present basic data for the design of a lateral bracing which supports the compression member at the center. In the study, elastic-plastic analyses of the compression member with initial deflection of one half wave were performed considering the transition of deflection mode from symmetry to asymmetry. The results obtained are summarized as follows: 1)In case the slendemess ratioλ>1.0 and the bracing stiffness is larger than the basic stiffness Kco, an asymmetric mode of the deflection appears at the maximum strength, and the magnitude of a bracing force is small and within 2% of the maximum load applied to the compression member. 2)In case λ>1.0, the necessary bracing stiffness to ensure that the carrying capacity reaches the target value and the bracing force is within 2% of the maximum strength is 1.4 Kco regardless of λ,. In case λ〓1.0, the necessary bracing stiffness increases as λ decreases, and it becomes 2.4Kco at λ,=0.2.

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Consept of the proposed "Steel-Concrete Composite Structure" is derived from "Steel-Hoop-Concrete Composite Structure" which has been already proposed by Prof. Suzuki, Prof. Takiguchi et.al. The followings are obtained from a foundamental experiment of which parameters are with or without covering concrete, compressive strength of concrete, equivalent width-thickness ratio of the flange, and axial force ratio. First, the covering concrete is evaluated on stiffness and axial bearing force, however is not cosidered as a structural part, becase it is crushed at about 1% of the slope angle and then bearing capacity is quickly going down. Secondary, in case of applying high strength concrete, the maximum bearing capacity and stiffness are incresed, however its defomational behavior is inferior to the applying ordinary strength. Lastly, the specimen with a combination of the above parameters indicates 6% of the slope angle at 80% reduction of the maximum bearing capacity, therefore the proposed "Steel-Concrete Structure" is considered to have possibility of applying as a structural member.

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