There are few studies on the consolidation and consistency of fresh concrete subjected to vibration, and the changing properties of consistency by vibration have not been explained theoretically. The purpose of this study is to establish the theoretical method predicting the flow behavior of fresh concrete subjected to vibration. In this paper, the behavior of a Bingham's fluid subjected to vibration is investigated from Theological and mechanical view points. Generally, the phenomenon that fresh concrete becomes more flowable by vibration is considered to be resulted from the apparent change of properties of the suspension material, but in this study, it is assumed that the consistency curve of a homogeneous material subjected to vibration does not change. In Bingham's fluid subjected to vibration, larger strain rate occurs compared with that under the same static shear stress because of vibrating stress, and average consistency curve under vibration can be calculated The average consistency curve measured in the sphere lifting test under vibration is obtained, and the results are compared with experimental ones in this paper.

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Flowing concrete with high flowability prepared with a river sand;river gravel and a crushed sand; crushed stone was investigated for mixture proportions, flowability, strength, shrinkage, carbonation and freezing and thawing resistance. The main findings can be summarized as follows. (1)The slump of the flowing concrete sufficiently filled up with a slight compaction ranges from 24 to 26 cm, which corresponds to a flow from 50 to 60 cm and a differential height less than 8 cm in the box test. (2)Flowing concrete with a water-cement ratio from 30% to 60% can be made by using two new admixture and by a simple correction of the standard table of the mixture proportion. (3)Flowing concrete can be produced with a specified concrete strength ranging from 180 to 600 kgf/cm^2.

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The passability is an important index for high-fluidity concrete to evaluate the characteristic of fresh concrete passing through a narrow space such as between steel bars with keeping aggregate. In this study, the ring penetration test was developed, in order to evaluate quantitatively the passability of high-fluidity concrete and to propose an easy testing method applicable to quality control of fresh concrete in construction site. To examine the applicability of this test method, the effects of various parameters such as material properties, width of passing section and pressure on the passabitity of high-fluidity concrete are investigated experimentally, and the Theological consideration is carried out based on theoretical and analytical approaches in this paper.

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It is important that the internal defect in cement mortar plaster finishing is found out before cement plaster is hardened. The purpose of this study is to investigate the possibility of it by using an infrared thermography. The conclusion from experimental results is following; Plastering materials, its bed and measuring time of the day are not effect on inspection of defect. The inspection is possible if thickness of coating is 10 millimeter or less. The inspection without destruction of plastering materials is possible by using an infrared thermography.

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In this paper, it is presented in-plane vibration analysis of rectangular plates. By using the method of superimposition, it is shown that solutions which satisfy identically the differential eqaution and which satisfy the boundary conditions with any desired degree of accuracy are obtained. The rectangular plates under consideration are as follows : a) Free- Clamped-Free-Claraped Plate, b) Clamped-Clamped-Clamped-Clamped Plate, c) Clamped-Free-Clamped-Clamped Plate and d) Clamped-Free-Free-Clamped Plate. Eigenvalues of four digit accuracy are provided for a wide range of plate aspect ratios. Accurate modal shapes are provided for the response of each rectangular plates.

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We presented an effective finite element method based on the thin-walled beam theory for the structural analysis of highrise building. However, the story deformation angles and shear forces obtained by this method are not acculate in the lowest story. In this paper, we show the matrix condensation methods based on the Uetani's idea in order to solve this problem. By numerical example of analysis of a highrise building, we show the validity of this methods, and we show it is possible to apply the present method to actual structural design.

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Using the concept of continuous shear constraints, an improved assumed displacement finite element method for shear-deformable plate bending element, its basic ideas being given in the former reports, is developed. A new series of quadrilateral plate bending elements is unifiedly and systematically derived. It is shown that the plate bending elements of the present family have no spurious zero energy modes and are "locking-free", with verification of the convergence criteria to be satisfied. Several numerical tests are performed, and show that the present elements have excellent accuracy and convergency for both thin and thick plates.

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When an initially straight thin cylinder is bent, there is a tendency for the cross-section to flatten. This is called "Brazier effect" and its characteristic is to decrease the stiffness with the increase of load. In the paper, the Brazier effect in a rectangular plate due to the pure bending is investigated from the following view points: (1) the reason of the occurrence of the Brazier effect in a rectangular plate, (2) factors which cause the Brazier effect and (3) quantitative estimate of the Brazier effect. The paper consists of 7 chapters: 1. Introduction, 2. Bending stiffness of multilayered plate, 3. Rectangular plate under the pure bending, 4. Analysis of Brazier effect, 5. Approximate method, 6. Numerical example and 7. Conclusion.

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A method for reducing earthquake load acting on piles by means of diaphragm walls installed around pile foundation is proposed. First, a shaking table test was carried out. Test specimens are 1/40 scale structural models, which consist of soil, piles and a building with or without diaphragm walls. The pile head moment of the specimens with diaphragm walls showed only 60% of that of the specimens without the diaphragm walls. An FEM analysis was carried out for both cases and the results were compared with the test results showing a good agreement. Furthermore, a simplified calculation method is proposed. This method takes account of the inertia force of buildings and the earth pressure to piles. The earth pressure is represented by Winkler's springs. This simplified model gives a good agreement with those experimental and analytical results and is proved to be applicable to design purposes.

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A tall building completed in April, 1994 in Niigata has been supported by friction piles due to local foundation characteristics. The project gave an opportunity to perform pre-monitoring settlement analysis, as well as to monitor the foundation behavior during a period of about 3 years, commencing at the initiation of construction and terminating 9 months after completion of the building. The main observation results are : The final maximum foundation settlement was 22mm, including 4mm in the last 9 months. As differential settlement of foundation increased, earth pressure and axial force on pile head were redistributed by the structural rigidity. With the increase in water pressure, the load shearing ratio between pile head and foundation slab varied from 2:1 to 4:1. It was comfirmed that foundation settlement under construction may be controlled to some extent by managing pumping water.

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In ultimate strength design, predicting accurately the deformation of a reinforced concrete column, up to the elasto-plastic stage, is very important. With this in mind, this study was carried out to clarify the deformation characteristics of reinforced concrete columns under high and/or fluctuating axial force. Reversed cyclic horizontal loading tests of six 4/13 scale high strength reinforced concrete column specimens under different axial loading conditions were conducted. The applied loads were based on the forces of the second floor columns calculated by the elasto-plastic seismic analyses of a 30-story reinforced concrete building. The test results made the assessment of the columns' strength and seismic performance feasible. A comprehensive investigation of the deformation characteristics was conducted by evaluating the flexural, shear, and other deformation components. The behaviors of the columns were observed to be significantly affected by the manner of application of the loads.

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The effects of spacing of shear reinforcement and the existence of sub-ties on shear strength were discussed both experimentally and analytically. Test specimens had an identical shear reinforcement ratio but different detailing. The effects were observed up to 25%. After the tests, the specimens were sawed in transverse and longitudinal directions. In the transverse sections, V-shaped crack patterns were observed, which was most peculiar in the specimens with narrow spacing of shear reinforcement and without sub-ties. Analyses were performed considering three dimensional fracture and the upper bound theorem. Calculated shear strengths and crack patterns approximately agreed with the experimental results.

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The long-teim loading tests of reinforced concrete cantilever beams were performed in order to understand and to clarify the mechanism of long-term deflection, especially the increase caused by the slippage of tension steel at the fixed edge on the reinforced concrete member after cracking. In the experiment six pieces of specimens were tested, and the slippage of the steel, crack widths and deflections were examined. Bond analysis equations for members on which different end bending moment acts were also presented. The analysis used the relationships between bond stress and slip proposed in the previous paper. Crack widths and deflections that occured by the slippage of steel were calculated by the bond analysis.

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The authors present a new concept to improve the performance of columns subjected to large displacements in the inelastic range. To lead transverse cracks prevent slant cracks caused the shear failure by inserting steel plates. These effectiveness are brought by separating concrete section and steel plates reinforcement. This paper describes the effectiveness of the steel plates inserted in a column and introduces another type with a new concept using the precast concrete blocks. The following conclusions can be obtained. 1) By inserting steel plates in a column the cyclic loading performance can be improved much caused separating concrete section. 2) By using the precast block the cyclic loading performance can be also improved. 3) These effectiveness are brought by changing the destruction mechanism of R/C columns.

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This is a report of a basic research on a practical application of Steel Bearing Walls. We approved that thin steel plates formed the tension field post-buckling under the in-plane shearing forces and thin films showed the same caracteristics. So we simulated this caracteristics by using thin films stretched on the frame with pantographmechanism. Increasing of the total length of the slits, the area of waving and the rigidities of thin films became smaller. From above results, we defined the concepts "slit-ratio" and "resisting area-ratio". We fined out the method of controlling of the rigidities of thin films and steel plates by the above concepts.

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In the mixed structure, composed of concrete-filled tubular columns and steel encased reinforced concrete beams, it is not clear the mechanism for transmission of bending moment and shear force acting on concrete part of beam ends. Through the two types of model tests, cruciform frame tests and cantilever beam tests, this paper investigates that shear force, acting on concrete part at beam ends, are transferred to the columns, by way of steel web or friction in compressive area of RC parts, and the RC portion can bear its bending and shear strength without some special measures for stress transfer at beam ends.

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