Extruding velocity in the extrusion moulding of cementitious components is one of the significant factors to control actual production processes. In this paper, a comprehensive method for predicting the velocity is proposed in the various cases of die opening geometries, barrel diameters and material conditions. The three following items are clarified in the various cases of machinery conditions. 1) Unit conveying rate per revolution can be determined by extruding pressure. 2) Extruding velocity can be estimated on the basis of die barrel opening ratio. 3) Unit conveying rate per revolution depends on water content ratio of mixtures.

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Drying weight loss and shrinkage at early ages of a high-strength flowing-concrete, using a one-pack type special admixture with a bodying agent, were studied by experiments with variable parameters including water-cement ratio, unit amount of water, type of cement and type of admixture. Major findings are as follows. (1) Regardless of the type of concrete, progress of shrinkage was significant when the weight loss was less than 1%. The shrinkage can be attributed to both drying and the other factors including hydration and autogeneous. (2) Progress of shrinkage was significant in the first 1 to 2 hours of drying (at the age of 3 to 4 hours) regardless of the type of concrete. Among mix parameters, water-cement ratio and unit water content had a larger influence on the shrinkage than type of cement and type of admixture. (3) When an ordinary portland cement was used, shrinkage at early ages of the concrete, with low water-cement ratio 0.27 and 0.3, became larger than that with water-cement ratio of 0.45 though their drying weight losses were smaller.

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In the present paper, it is tried to evaluate quantitatively the rheological constants of fresh concrete. In this study, it is verified that the apparatus for shear box test is suitable to measure the rheological constants under low shear rate smaller than 1 (l/s), and the effects of the shear layer thickness, the volume fraction of aggregate and the shape of aggregate particle on the rheological constants of model suspension materials are investigated. Moreover the changing process of a consistency curve according to decreasing slump-flow value, and ranges of yield value and plastic viscosity of high-fluidity concrete are investigated quantitatively.

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Influence of fine aggregate concentration on air permeability of cement mortar is experimentally and analytically studied. The air permeability of cement mortar specimens of various fine aggregate concentrations were first measured. It was found out that an increase of concentration slightly reduced air permeability of the mortars in the range of lower concentration and, on the contrary, noticeably increased it in the higher concentration range. This results suggest that air permeability affected by the existence of boundary layers, which are considered to be highly porous, around the fine aggregates. Then, the two dimentional model composed of three components such as cement paste, fine aggregate and boundary layer was proposed, and the air permeability were calculated for mortars of various fine aggregate concentrations. Finally, the influence of concentration on air permeability of mortars was quantitatively discussed on the basis of the measured and calculated results.

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A new type admixture was developed for super workable concrete in water-cement ratio of 40-55%. The cost of concrete using this admixture will be less expensive because of using less powder and admixture content. This admixture is the polycarboxylate type water-soluble copolymer composed of the cement dispersing component and the water reducing component which effect segregation resistance. Since these components have closely chemical structures, the solution of this admixture is very stable. Super workable concrete using this admixture has as same fluidity and segregation resistance as usual super workable concrete, though having less viscosity. The properties of this hardened concrete, -strength, shrinkage, durability and fire resistance-, and influence of mix proportion were made clear by investigation in comparison with conventional concrete that has same water content, same water-cement ratio and slump of 18cm. And the appropriate mix design method of this concrete was proposed.

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It is increasingly desired to develop an accerelating corrosion test method in order to estimate the durability of the metallic building materials used in marine environment. The authors provide to manufacture a cyclic corrosion test which is programmed to control the temperature, humidity in test chamber and spraying artificial seawater to the metal specimens. Here, many samples of galvanized steel, titanium, stainless steel and aluminium were tested. The results of the artificial corrosion test were compared with those of the natural marine exposure test and the reproducibility of new method was discussed.

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The effect of cross sectional size and shape of polysulfide sealing beads on shear fatigue resistance to shear movement was studied experimentally and analytically. Nine kinds of rectangular sealing beads with different sizes and six kinds of concave shape beads were repeatedly deformed by shear joint movement. The time to cracking was not affected by size for the rectangular beads, and it became shorter for the beads with deeper concave shape. To learn the reason for these results, the stresses of the beads were studied using a finite element method. It was concluded from both experimental and analytical results that a durable cross section of a sealing bead to shear movement is rectangular or slightly concave shapes.

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If the sense of sight and dynamic feeling that gives the operator the feeling of being at the site can be given to the operator, repairs of the wall surface can be realized not from on the staging but on the ground. By the use of this technology, extreme work including deep excavation and sheathing work can be carried out safely and effectively. This paper summarizes the experiments of and research into the technology for presenting information that gives the feeling of being at the site to carry out such construction work remotely, and states the necessity and possibility of this field of research.

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It may be difficult to reduce the earthquake disaster such as human losses and building collapse to zero in the severe strong ground motion. The most important thing in the prevention of the earthquake disaster is to reduce the seismic damage to the slightest level which does not yield extreme social impact and is easy to restore the damage. The social response can be estimated by the amount of report about seismic damage in the newspaper. The report ratio of seismic damage to total report in newspapers is surveyed for 30 days after the event for the earthquakes which yield heavy disaster from 1946 to 1995. The report ratio decreases with day after earthquake and it can be approximated by the exponential function. The slightest level of seismic damage is estimated using the relation of the magnitude of report ratio or the continuance of the report ratio and the total seismic damage which is defined as the function of the number of human losses and collapsed buildings.

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An analytical method is presented for computing horizontal-to-vertical spectral ratios (H/V) of Rayleigh and surface waves propagating on a layered half-space, in which the effects of their higher modes are taken into account. Assuming that the amplitude ratio between Rayleigh and Love waves is 0.7 at any given frequency, both H/V ratios of Rayleigh and surface waves are computed at six sites, and compared with those of microtremors. The computed variation with frequency of surface waves shows better agreement with that of microtremors than that of Rayleigh waves. This indicates that the microtremors consist mainly of surface waves and that their H/V ratios can be estimated by the proposed method.

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This study investigates bedrock motions on an outcrop of Rokko granite rock and site amplification characteristics due to deep irregular underground structures in Kobe City during the 1995 Hyogo-ken Nanbu earthquake. Six sections normal to Rokko Fault are modeled based on 2-D seismic profiles determined from geological surveys. Peak velocities of bedrock motions deconvolved from 6 records show almost the same level, 50-60cm/s, while those on an outcrop of Osaka group are 86-137m/s. Ground motions at sea side area can be well simulated, indicating that bedrock motions are expected to be properly evaluated. In soil responses on Osaka group, the large amplifications can be commonly seen at area about 1km away from basin edge to seaside, while the transfer functions from the bedrock are varied according to the bedrock shapes. Distributions of maximum responses are accountable for the distributions of damaged structures.

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The first part of this paper outlines a proper and efficient method to quantify both temperature- and frequency-dependent properties of a viscoelastic damper (VED) by random loading test, and shows that a generalized Maxwell model can be used to exactly simulate those properties of the VED. The second part deals with an analysis method for structures with VEDs simulated by generalized Maxwell models. The method is quite efficient because it can eliminate degrees of freedom of the nodes between springs and dashpots which constitute generalized Maxwell models. The validity and efficiency of the algorithm are shown through an appropriate sample analysis.

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A new incremental geometrically non-linear analysis method with moving coordinate systems which are continuously moving and rotating during every incremental loading step, is proposed in this paper. This method is adopted for thin-walled structures with planer shells. The geometrical non-linearities treated by the moving coordinate systems and by Von Karman's plate theory, mainly express overall and local buckling deformation, respectively. A rectangular planer shell element on the basis of Von Karman's plate theory, is applied. The efficiency of this method is demonstrated by some example analyses.

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A method is proposed for analytically expressing a point on a story shear force-interstory drift curve (Q-D curve) in the elastic-plastic range of a building frame subjected to a set of static horizontal forces in terms of total quantities of nodal displacements and angles of nodal rotation. An incremental elastic-plastic response analysis need be done once to find the positions where plastic hinges are formed. A procedure has then been developed of deriving the sensitivities of the point on the Q-D curve with respect to the second moment of area of each member. This sensitivity may be used in reduced model-frame inverse transformation.

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The present study proposes a new proportioning method how to decide the cross sections of the members in single layer reticulated shells. The method considers elasto-plastic behaviors of the members, the member instability and the global shell buckling. The procedure for proportioning method includes; (1) a second-order elastic analysis to evaluate the equivalent slenderness ratio of each member, (2) a column buckling concept to calculate the column buckling strength of each member, and (3) the knock-down factor for shell-like buckling. The validity of the proportioning method is discussed by showing that roof-typed cylindrical reticulated shells designed by the present procedure accurately satisfy their required ultimate design loads.

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In this present report, we describe a fundamental study of method seeking for a hollow section by an automatic design. And, we carry out inspection experiment and describe shape of effective hollow section too. The substance is a method seeking for hollow section decision factor arufa(α), beta(β), gamma(γ) automatically from hollow section decision figure. And shape of effective hollow section is oval model and it was proved by inspection experiment too. As a result, it understood that it can decide a hollow section of bending precedence failure type easily.

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This paper deals with the ultimate flexural strength of reinforced concrete columns composed of two elements with different concrete strength. The authors carried out the flexural tests under the varing main reinforcement ratio and the varing axial load. The authors investigated the contribution of the main reinforcement, the core and the shell to the ultimate flexural strength of the columns by the fiber model method and the superposition method, and obtained some modification coefficients for these ultimate flexural strength. And we derived the superposed strength equations including these modification coefficients.

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In order to improve the understanding of earthquake resistance characteristics of prestressed concrete (PC) structures designed by the current design method (route-3a), the following researches had been performed : (1) Determination of earthquake load, dead or live loads and indeterminate force in design. (2) Comparison between ultimate strength of PC beam, strength developed by PC bars in the PC beam section and required strength of beam in design. (3) Comparison between ultimate strength of columns and required strength of column in design. (4) Static elasto-plastic analyses of designed frame. The main result of this study is that equipment of PC bars in beam section is not a factor in over-strength against required strength in design and PC frame structure has the story whose shear strength is lowest of all stories in the structure essentially and this feature is caused by the large dead or live load of the structure.

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In Hyogoken-Nanbu earthquake which occurred in January, 1995, a lot of steel structures brittle fractured. It is necessary to make relation between the brittle fracture, the plastic strain record and the property change clear to prevent the occurrence of the brittle fracture. In this study, it carried out the investigation of the damage situation about some steel structure which was suffered by Hyogoken-Nanbu earthquake. Also, it gathered test pieces from the steel structure and it carried out Charpy impact test, Vickers hardness test and tensile test. It made the situation of the property change clear as the result. Also, it made relation between the plastic strain record and the property change clear.

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This paper proposes performance based seismic engineering, which is applicable to special use buildings, focusing on functions of the buildings. The concept is that functions of a building after an earthquake depend on damage of elements, structural one, contents etc., and the performance of elements is defined on the basis of the required functions. Two performance matrices are proposed. The first matrix incorporates function level with design loads and building grade. And the second one shows design criteria of elements. Further, detailed criteria and a method to evaluate a seismic load are described for a thermal power plant building.

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In the recent years, destruction of ozone layer by CFC has resulted in an increase in the amount of ultraviolet radiation reaching the earth surface. Especially, the effect of ultraviolet radiation in coastal zone is higher than that in inland area due to the reflection from the sand surface. These large amounts of ultraviolet radiation are capable of causing health problems involving the skin cancer and eye damage of people. This report shows measurements of ultraviolet spectral reflectance on the sand in order to investigate the relationship between reflectance and sand surface characteristic. From the measurement results, the ultraviolet reflectances on sand are about UV-A 3-33%, UV-B 3-19%, UV-C 3-17%. The ultraviolet reflectance can be estimated by visible reflectance. As sand's lightness becomes higher, ultraviolet reflectance also becomes higher.

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An algorithm for pulse response of non-slip rigid body is developed using ellipse functions. Then seismic response without numerical integration is computable replacing seismic record as pulse series. The numerical experiment shows good accuracy and strange tendency of overturning becomes clear. To investigate and overcome the complexity, overturning response spectrums are proposed with examples using Koube earthquake record. Then the record is approximated by 4 triangular pulse. The attempt showed good coincidence in overturning tendency and explain some reasons of the complexity.

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Energy input rate of earthquake ground motion in above paper were discussed as following items. 1) Definition of energy input rate. 2) Relation between energy input rate and yield strength of structures

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The discussion is focused on the definition of energy input rate and the relationships between energy input rate and yield strength. First, Dr. Inoue proposed that energy input rate should not include an elastic component, because the elastic component is charged during the preceding cycle. However, the authors still insist that the energy input rate should include the elastic component from the viewpoint of earthquake load effect to structures which can be applied consistently to structures of poor to rich ductility. The energy input rate of Inoue's definition converges to zero for non-ductile linear-like systems which will cause an awful procedure in design. Second, Dr. Inoue stated that the energy input rate excluding the elastic component is regardless of system's yield strength. His statement obviously violates the theory of displacement conservation. The authors demonstrated that the energy input rate, even though the elastic component is excluded, is not constant but is influenced by the yield strength.

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