In this study, considered coarse aggregate and mix proportion affect drying shrinkage of concrete, young's modulus of coarse aggregate and mix proportion was verified the effect of drying shrinkage. Young's modulus of coarse aggregate was estimated by Hashin-Hansen equation. It was estimated from young's modulus of basis material for young's modulus of another material. Mix proportion of concrete was verified effect of different coarse aggregate. In this verification, relationship between coarse aggregate and effect of r1 were correlated. The coefficient effect of r1 was proved to correct in the young's modulus of coarse aggregate.

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Water transfer behavior in hardened cement paste is evaluated. For evaluation of water transfer, mass loss of specimens over time is measured and Boltzmann's method is applied to measured data. At the same time, desorption isotherm of hardened cement paste is evaluated. Using the diffusion coefficient for nominal water content and desorption isotherm, water conductivity for chemical potential of water in hardened cement paste is derived. Nine hardened cement paste specimens, which have different porosity, are tested and using these data, predicting model of water conductivity is proposed.
The proposed model needs the properties of hardened cement, such as, maximum water content at 20°C degree, water vapor BET surface area, and water content for predicting the water conductivity. According to the simulated results, the temperature dependency of water conductivity is obvious. Evaluation of temperature dependency of water conductivity is remained to be future issue.

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The aim of this research is to propose a method to predict the strength development of concrete using equivalent age. The experiment of strength development was carried out. Ordinary Portland cement, moderate-heat Portland cement and low-heat Portland cement were used for concrete specimen. Water cement ratio was ranged from 0.3 to 0.6. Strength development of concrete cured below subzero temperature was examined too. The result showed that the apparent activation energy in equivalent age equation depends on mineral composition of cement. Furthermore, the effect of freezing on the reaction rate of strength development was shown. Consequently, the strength development of concrete can be estimated from mineral composition of cement, nominal strength of concrete and curing temperature by the method proposed in this paper.

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Coarse aggregate adhered mortar and lumps of mortar are produced from mixed concrete for the experiment, influence of existence form of mixed mortar on the properties of recycled coarse aggregate concrete is examined. As the result, it is confirmed that compared to adhered mortar, residual lumps of mortar have a profound influence on compressive strength, static modulus of elasticity and length change of recycled coarse aggregate concrete. Meanwhile, recycled coarse aggregate concrete is equivalent to splitting tensile strength of ordinary coarse aggregate concrete. In addition, it is confirmed within the study that water-cement ratio of the original concrete have little influence on the properties of recycled coarse aggregate concrete.

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This paper made it clear that ultrasonic examination and the method of monitoring voltage and current can be applied to manage the tensile shear strength of welded joint,paying attention to the following items.
In case of ultrasonic examination by using the rubber sheet on spot weld surface in immersion technique,the porish treatment of indentation affects the measurement accuracy.
In using AC spot welding machine and applying the method of monitoring voltage and current, we must calculate the resistance which contribute heat generation from measured voltage and current by eliminating the influence of inductance.

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For non-destructive and non-invasive inspection of water content and chloride concentration of concrete, a new electric method, by measuring the impedance between two rectangular metallic electrodes setting on the surface of the sample using the impedance meter with an AC voltage at frequencies of 10 Hz to 100 kHz was proposed. This paper describes the basic research of this easy, cheap, onsite, and non-invasive inspection system. First, the effects of water content and chloride concentration on the measured impedance dependence of frequency of small concrete samples were investigated. Secondly, the phase shift dependence of frequency was measured to estimate water content and chloride concentration individually by the peak of the phase shift and its frequency. Finally, the equivalent circuit of concrete that reproduces the curve of measured phase shift dependence of frequency by fitting the curves obtained from the equivalent circuit and measurement was proposed. It was shown that there is a possibility to estimate the water content and chloride concentration of concrete.

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The influence by the testing time was examined about the shrinkage compliance examination of tiled finish. As a result, the shrinkage compliance examination and the value of the destruction point with short loading time is found to show better performance than the case where the shrinkage progresses over a long period of time. Moreover, it proposed the method of evaluating the decrease of tile adhesion from the result of the shrinkage compliance examination. And, it was clarified that the decrease tendency of the bond strength of the tile finish can be estimated by using the proposed shrinkage transmission remaining rate.

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The digital terrestrial television which uses the electromagnetic wave of UHF band was started in December, 2003 and it will be shifted completely by July, 2011. In this paper, the electric field strength level is measured in the reception condition that is different of the distance and height and in city. As a result of the measurement, the following have been understood.
1. The electric field strength level decreases as the distance parts but the influence that buildings and landform give it is larger.
2. The electric field strength level increases as the reception point rises and are almost constant.
3. The distance from buildings and the direction of the electromagnetic wave influence the electric field strength level because of the diffraction of it.
4. The amount of attenuation at the electric field strength level is large in the city because the building is large and it is overcrowded.
The study is critical data in link budget analysis of the electromagnetic wave of the digital terrestrial television.

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Ultimate strength of wide roof-type shallow arches of reinforced concrete is discussed for pin support at both ends under vertical loads. The method considers the effects of not only initial geometric imperfections but also the tensile strength of concrete. The effect of sectional shape is included; a flat plate section and a curved section like a spherical surface. The results reveal that the ultimate strength of curved section is larger than that of flat section, the ultimate strength under uniform load is not reduced so much only if there are no geometric imperfection, however, the ultimate strength is largely reduced due to geometric imperfections and anti-symmetric vertical loads, and this tendency is much amplified in case of no concrete tensile strength, and followed by a suggestion that strength against earthquake forces should be studied for shallow arches to be built in area with high seismicity.

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This paper proposed a form-finding analysis method of the grid shells that formed by applying forced displacement to the grid plate, which is composed by connecting some rods with pinned joints on the ground. The forced displacement is decided by the optimization technique, so that the equilibrium shape of the grid plate precisely approximates the curved surface shape demanded by designers. The setup of this optimization problem and its formulation are described in detail. In the numerical example, various curved surfaces are formed from one grid plate by the proposed method. Furthermore the model experiment is conducted, and it is confirmed that the curved surfaces obtained by the proposed method can be actually formed. The deformation form and stress distribution of the grid plate are measured and they are compared with numerical results. Through these results, the effectiveness of the proposed method is shown.

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Most of the structures of variable geometry are designed as statically determinate structures since they can vary their shape by changing the length of members without accompanying any redundant inner forces. However most of the general structures involves statically indeterminacy and control of redundant inner forces enable us to control stress distribution in the structures. In the paper we describe how to select the member lengths changes that involves no redundant inner forces, without asking statically determinacy of the structure. Then we propose to calculate the optimum transformation path of the structure starting from initial given shape to the final objective configuration without associated any redundant inner force. Some numerical examples are also given and discussed.

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We, in this article, propose a manual calculation method for the stiffness and ultimate slip of the timber joint composed of a few drift pins. The effect of the clearances between the holes and drift pins on the stiffness of the joint were modeled as the extreme-value distribution of each clearance.The effect of the number of the drift pins on the ultimate slip of the joint was modeled using the weakest link theory of the ultimate slip of the joint, and the effect of the concentrate tensile stress perpendicular to the grain at the timber parts between the drift pins on the ultimate slip of the joint was mechanically modeled. The validity of the proposed calculation method was confirmed by the experimental results.

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In order to consider an effect of transverse reinforcements in reinforced concrete (R/C) columns, which raises compressive strengths of the columns, a theoretical solution of compressive strength based on the upper bound theorem was shown in this paper. A tri-axial yield criterion for concrete in plane strain was assumed with two parameters in this solution. The theoretical solution was compared with experimental results of compressive tests of R/C column specimens, which the specimens had transverse reinforcements in the ratio from 0.2% to 1.2 % and those maximum compressive strengths accompanied with yielding of reinforcements. As results, it was concluded that the maximum compressive strengths of R/C columns could be estimated with the yield criterion of σ₃=.σ_C +σ₁ for average stress in concrete, where σ_C, σ₁, and σ₃, were an apparent uni-axial compressive strength in R/C column, the maximum and the minimum principal stresses, respectively.

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The purpose of this paper is to propose the structural characteristic factors (k_D) of moment-resisting steel frames(MRFs). Simplified single-degree-of-freedom (SDF) systems with two shear springs are used as analytical model. Two shear springs consist of column with elasto-perfectly plastic behavior and beam with lateral buckling behavior. For the analytical models, statistical properties of k_D are studied by seismic response analysis subjected to 118 accelerograms. This k_D factor depends on deformation capacity, strength ratio of beam and natural period of the structure. Based on the analytical results, this paper proposes simple formulae of mean value and coefficient of variation of k_D. Then, k_D factors corresponding to the story drift angle are calculated for five different types of MRFs by using SDF systems.

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The restraint effect of the slab on lateral buckling of composite beams within frames under seismic loading was examined experimentally and analytically. The effects of the beam slenderness ratio, web thickness ratio and presence of holes in the web were investigated. Regardless of parameters, all tested beams did not experience buckling until a certain large displacement confirming that the effect of lateral buckling restraint of the slab was very effective. The ductility factor of the composite beams was assumed based on the elastic lateral buckling strengths that were determined by the eigenvalue analysis in which the slab restraints were modeled by a lateral transverse restriction and a rotation spring on the top flange. By comparison of the analytical and tested results, the conventional formula proved to be adequate for the evaluation.

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This paper describes experimental and analytical studies on square hollow section column to H shaped beam connections stiffened by exterior ring diaphragms. Tensile or compressive tests using by simplified model specimens were carried out to investigate the effect of the connection details. The full plastic strength is obtained by applying limit analysis to the collapse mechanism, which consists of the yield zone on the column wall, on the ring diaphragm and on the beam flange. Further, practical formulae are proposed for predicting the yield strength and the ultimate strength of the connections.

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Authors have proposed WF, the new limitation value of plate slenderness ratio, which takes stress distribution within H-shaped beams and coupled instability of the web and flanges into consideration. The purpose of this study is to generalize WF to various types of structural steel. In this paper, authors clarify interactions between plastic deformation capacity and mechanical properties of H-shaped beams, explain the adaptation validity of WF, and establish sets of WF for each type of steel.
As a result, authors found that WF successfully evaluated plastic deformation capacity of H-shaped beams generally and uniformly, regardless of types of steel.

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This paper proposes a simple model of a force transfer mechanism for predicting the ultimate stress in a concrete filled steel tube column connection using reinforcement. The model assumes a prying action from the steel tube to the reinforced concrete element. It involves bearing stress in the concrete element, tensile stress in the steel tube web caused by the prying action and bond stress between reinforcement and concrete. This research verifies the analytical model by comparison with experimental results. The analytical results agree approximately with the experimental results for the ultimate stress in the region of the force transfer mechanism.

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Experimental and analytical achievements on the block shear strength of wood in the above paper are discussed about the following items: 1) The proposed failure criterion seems inadequate, because the compressive stress does not act on both sides of the failure section. 2) The elastic modulus for FE analysis seems inadequate, because the Young's modulus in the transverse direction is too small. 3) The proposed equation for bearing deformation seems inadequate, because it is contradictory to the proposed strength criterion. 4) The test specimens seem improperly arranged, because the directions of the grain are inclined or curved to the bearing force.

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The authors wish to thank Prof. Hitoshi Kuwamura for the discussion. The answer to his questions are as follows:
1) Our proposed criterion is adequate, because Prof. Kuwamura ‘s criticism seems exclusive based on his understanding of basic fracture criteria from the sight of mechanics. 2) The elastic modulus for FE analysis is adequate, because it was based on AIJ standard. 3) Our proposed equation for bearing deformation is adequate from the sight of our aim, because Prof. Kuwamura ‘s discussion is not taken into account in our aim of investigation. 4) The test specimens were adequate from the sight of our aim, because Prof. Kuwamura ‘s discussion is not taken into account in our aim of investigation.

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