Through the study of the relationship between the inter-action of human psychological response to the vibration of a certain artificial walking surface, and the physical characteristics, measured under practical loading conditions, this paper will attempt to present the method for evaluating floor vibration when a different person causes and percieves the vibration. At first, a sensory test was conducted using scores of sample floors. Based upon the results of the sensory test, the evaluation scales for the psychological responses to 14 different kinds of testing objectives were constructed. Then, the physical characteristics of the sample floors were measured employing a "vibration testing device for floors". From the results of the measurements, VI (2) (Vibration Index (2)) was calculated as the physical value which indicates the vibration greatness of human sensations. Next, based upon the relationship between the evaluation scales and VI (2), the evaluation in-dices of the floor vibration were obtained. Finally, the evaluation method was presented, which is composed of the measurement method of VI (2) and the evaluation indices.

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In the previous paper, the authors had carried out the creep strain analysis of prestressed concrete member under following assumptions for creep and crying shrinkage of plain concrete, i. E., (1) proportionality of creep strain to stress, (2) superposition of flow creep strain, (3) same strain rate at the same time elapse after loading for delayed creep strain, (4) neglect of creep recovery after removing the applied stress, and (5) shrinkage strain curve similar to flow creep curve. However, expressions obtained on the creep loss in prestress and the time-dependent strain of prestressed concrete member showed that the effect of the shrinkage of concrete upon those is only given as a function of flow creep factor of plain concrete without regard to the delayed creep factor due to the assumption of (5). Such a result seems to be somewhat improper from the viewpoint of analytical logic. Thus, in this study, applying the assumption that shrinkage strain of plain concrete is in proportion to the sum of flow and delayed creep strain, the analysis of loss in prestress as well as time-dependent strain were carried out again on the prestressed concrete member, and average axial and rotation creep factors for calculating the axial creep deformation throughout the whole length of member and creep rotating displacements at both ends of member were defined from the expressions obtained. Also, numerical calculation results of the prestress loss and creep deformations from the equations derived in this study obtained good agreements with those from previous study.

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Generally, the ultimate strength of restrained concrete square slabs express larger value than the bending strength obtained from the yield line theory of Johansen. This cause is explained by an arching action due to the development of compression membrane force in the slab. Therefore, in this report we described the relation between the evaluation value and its effecting factors: The evaluation value (E) express a strength grow due to the development of compressive membrane force in the slab. The effecting factors were considered by the items of three: Slab's thickness/span ratio (H/L) or flange thickness/span ((H-h)/L), elastic fixing degree (F_<ix>) and reinforce factor (q). We investigated the relation between the evaluation value and effecting factors as follow: 1) Relation between evaluation value (E) and slab's thickness/span or flange thickness/span ((H-h/L). 2) Relation between evaluation value (E) and elastic fixing degree (F_<ix>). 3) Relation between elastic fixing degree (F_<ix>) and slab's thickness/span ratio (H/L) or flange thickness/span ratio ((H-h)/L). 4) Relation between evaluation value (E) and reinforce factor (q). The results was shown as follow: 1) As the value of slab's thickness/span ratio (H/L) or flange thickness/span ratio ((H-h)/L) increases, the evaluation value (E) showed an increasing tendency. Therefore, the evaluation value (E) was very closely related with slab's thickness/span ratio (H/L) or flange thickness/span ratio ((H-h)/L). 2) As the value of reinforce factor (q) increases, the evaluation value (E) showed a decreasing tendency. 3) Elastic fixing degree (F_<ix>) was very closely related with slab's thickness/span ratio (H/L) or flange thickness/span ratio ((H-h)/L). 4) Elastic fixing degree (F_<ix>) gave an effect in the strength of slab by restrained degree of rotation with surround restrained beam. But it was found that the elastic fixing degree (F_<ix>) gave a small effect to the evaluation value (E).

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The restrained orthotropic square reinforced concrete slabs with shear reinforcing bar which has two way is considered to be property of both X direction and y direction '. Transverse hollow system reinforced concrete hollow slab and longitudinal hollow system reinforced concrete hollow slab. Therefore, in this report we described on obtainning the load-deflection curve of the square reinforced concrete hollow slabs with shear reinforcing bar that happened shearing failure by applicable shearing strength equation of the both end fixed one way RC hollow slabs to the suggestion equation of the previous report and compared the curve of calculated results with the curve of experimental values, then investigated. The result that the curve calculated values showed a fairly good approximate tendency of the curve experimental values found.

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We have conducted a series of empirical studies to examine effect of openings placed within a wall panel such as for penetration upon the load-deflection characteristics of a shear wall. The major purpose of the study is to examine effect of openings within a wall panel upon structural properties of a heavily reinforced concrete shear wall such as the ultimate strength, ductility capacity and load-deflection hysteresis characteristics. Herein this paper, we discuss the experimental results obtained during a series of empirical studies. We examine in detail the effect of the size, location, shape and number of openings positioned within a wall panel on the variation of structural properties of a shear wall. We have summarized the results obtained from a set of significant data during the experimental studies as follows: 1. Location of an opening within a wall panel will determine a possible failure mode of the shear wall. When an opening is positioned at the bottom of a wall panel, the failure mode of the wall is a sliding shear failure at the bottom of the panel. When not, the failure mode is a compressive shear failure along the diagonal direction of the wall. 2. When an opening is positioned at the bottom of a wall panel, the observed ductility capacity is inferior to that obtained in a wall with an opening in the middle height of the wall. Based upon the empirical results, we propose an analytical formula to evaluate the shear strength of a wall having various types of openings within a wall panel, by use of which we can estimate the ultimate strength of a heavily reinforced concrete shear wall taking openings within a wall panel into consideration.

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The restoring force characteristics of steel frames can be decomposed into the skeleton part, the Bauschinger part and the elastically unloaded part. Hitherto, in most cases, the Bauschinger part has been disregarded in evaluating the seismic resistance of steel structures, and the contribution of the Bauschinger effect to the seismic resistance has been left unknown. In this paper, the shape of the Bauschinger part in the restoring force characteristics of steel moment frames is made clear experimentally, and the influence of the Bauschinger effect on the seismic resistance of steel moment frames is clarified through dynamic response analyses allowing for the Bauschinger effect. It is demonstrated that the influence of the Bauschinger effect is remarkable and the energy absorption capacity of steel moment frames can be doubled by the Bauschinger effect.

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Strength characteristics of steel beam-columns are discussed by statistically evaluating the data obtained from previous experimental studies. A total of 237 test data are selected in this study, and their individual properties like material and geometrical properties and maximum resistances are stored in a computer in the format of a relational data base. Strength of the test data (designated as the experimental strength) is calibrated against the strength assumed in the strength provisions of the LSD Specification (designated as the predicted strength), and following observations are made. (1) The experimental strength is 15 % larger on the average than the predicted strength. (2) The experimental strength relative to the predicted strength is larger for beam-columns with moment-gradient than for those with uniform-moment, and it occurs most likely because the effect of strain hardening on the strength is not included in the predicted strength. (3) If the nominal yield stress is used instead of the real yield stress, the difference between the experimental and predicted strengths is expanded further by 7 %. (4) The experimental strength is 36 % larger on the average than the design strength stipulated in the LSD Specification. (5) The primary source that have produced the difference between the experimental and design strengths is not the variation of yield stress but the error involved in the predicted strength.

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The purpose of this paper is to propose the method of reliability evaluation for structural systems using the higher-order moment standardization technique. In the reliability evaluation of structural systems, it is necessary to calculate the joint occurrence probability of multiple failure events that the system has. This paper formulates the joint occurrence probability of multiple failure events using the moments alone in a form that includes the non-Gaussian property of probability distribution. A method of reliability evaluation for structural systems is proposed by using the joint occurrence probability. Failure probabilities of several types of frame structure are calculated through the proposed method. The solutions by the proposed method agree with those by Monte Carlo simulation with sufficient precision.

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From an economical point of view of minimizing the sum of the expected value of total loss caused by disasters and the construction cost, the paper describes a probabilistic method for estimating the optimum initial resistance of structures with deteriorating resistance during the life of structures, and discusses the decision making of the load factor for such a structure.

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Based on Mindlin's plate theory, free vibration of simply supported rectangular plates is investigated by using the method of superimposition. In this paper, for a simply supported edge the conditions are w=0, M_x=0, M_<xy>=0 on x=constant. Eigenvalues of four digit accuracy are pro-vided for a wide range of plate aspect ratios, thickness to width ratios, and modal shapes. Numerical results are compared with those of classical solutions.

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We present various types of evaluation methods of causal discrete impulse response of unbounded soil, which are necessary for the substructure approaches working in the time-domain nonlinear response analysis considering the soil-structure interaction effects. The discrete impulse responses are obtained either by the Hilbert transform using the FFT algorithm (Causal FFT treatment) of the flexibility of soil calculated in the bandlimited frequency range or by the discretisation of the continuous impulse response formulated in the time domain. The dynamic property of the impulse responses and their effects to the response analyses are examined by comparing the asymptotic property of the flexibility soil in the frequency with the asymptotic property of the impulse response in the time domain, and through earthquake response analyses.

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In the present paper, the effect of imperfections on the elastic buckling loads and mode shapes of externally-loaded single layer reticulated domes is investigated. The types of buckling concerned here are the general buckling, the local buckling and the member buckling. As to the geometrical parameter of domes, the characteristic value S is adopted which represents the openness and slenderness of the dome. The maximum value of the imperfection is assumed to be the normal random variable. The buckling loads are computed by the linear and the nonlinear buck-ling analysis using the finite element method. The statistical values are calculated by the three-points estimates method. The main points of interest are the influence of the shape and the extent of an imperfection on the buckling loads.

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Failure rate and fire rate were calculated by two kinds of data bases in this study. One kind of the data base refers to architectures and devices attached to them, where it contains building use, structure, the number of floors, the total floor area, the devices' inspection results, and etc. Another kind of the data base refers to fires, where it contains the state of a fire in addition to the same kind of informations in the above data base on the fire building. It was calculated the failure rate [failures/day] of the emergency lighting system as a safety device and the fire rate [fires/m^2・year] with these data bases. It was analyzed the profile of the failure rate and the fire rate on the building use and the total floor area of a building. The results are summarized as follows; 1. The failure rate and the fire rate calculated in this study have the same profile on the change of the total floor area of a building in each building use. 2. The profiles of the failure rate and the fire rate on the change of the total floor area of a building are divided into two types according to the building use. On type is, as is shown in the office use, that the failure rate and the fire rate increase in proportion to the increase of the total floor area. Another type is, as is shown in the apartment use, that the failure rate and the fire rate are almost constant regardless of the increase of the total floor area.

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