In the previous study, the analysis method based on the bond analysis was proposed to estimate cracking behavior due to drying shrinkage in RC wall, and the validity of the analysis method was verified from experimental study. However, because there is a shortcoming that calculation is complex, the simple estimation method is demanded. Accordingly, for the more simple estimation of the crack width and number of cracks of RC wall in the buildings, an improved and simple equation based on the bond analysis was proposed in this paper, and the calculation values were compared with the experimental values.

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A 20 liters chamber which is standardized in JIS A 1901:2003 “Small chamber method - Determination of the emission of volatile organic compounds and aldehydes for building products” has been popularly used for measurement of volatile organic compounds (VOC) emission factors from coating materials. A 3 liters chamber which was newly developed for measurement of VOC emission factors from coating materials was evaluated and compared with the 20 liters chamber in the study. Air tightness, recovery and mass transfer coefficient of the 3 liters chamber were evaluated in accordance with JIS A 1901:2003. Further, correlation between VOC emission factors obtained by the 20 liters chamber method and the 3 liters chamber method was examined through measurement of acrylic enamel paint and a textured coating material.
The results can be summarized as follows;
1) Air tightness of the 3 liters chamber meets the requirement of ENV13419-1:1999 “Building products, Determination of the emission of volatile organic compounds - Part1: Emission test chamber method.”
2) Recovery and mass transfer coefficient of the 3 liters chamber satisfy the requirements of JIS A 1901:2003.
3) VOC emission factors obtained show high correlation between the 20 liters chamber method and the 3 liters chamber method.

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This paper proposes a methodology for seismic risk evaluation of a building portfolio considering the amplification characteristics of earthquake ground motions due to subsurface structure. The main features of the methodology are the following: (1) The response spectrum method is used to calculate the maximum responses of buildings such that the period characteristics of both ground motion and building can be considered for seismic risk evaluation. (2) Considering that the variability of ground motions on the bedrock is not great, a probabilistic response spectral model with spatial correlation on the bedrock of each site is developed such that the amplification of ground motions at each site due to subsurface structure can be reflected into the seismic risk for a building portfolio. This paper also presents a case study for a building portfolio composed of twenty imaginary buildings in Sendai area to verify the features of the methodology.

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Structural vibration control is categorized into passive control, active control and semi-active control. Semi-active control using a variable damper stabilizes building responses in an earthquake better than the conventional passive control and active control.
This paper used variable hydraulic damper and MR damper. The servo valve of variable hydraulic damper controls the oil flow between two rooms of the cylinder divided by the piston. MR damper changes its damping force by changing the magnetic field acting on the MR fluid according to an electric current. As the first step of the research, in order to evaluate the performance expected from the theoretical study, a dynamic loading test was conducted. Next, authors conducted experiment by the base-isolated specimen of two-degree-of-freedom structure. Finally, the damping performance and control characteristics of semi-active damper were verified.

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We propose to use piezoelectric ceramics (PZT) with shunted circuits, as a technique to reduce structure-borne noise of steel bridges. This technique changes vibration energy of steel bridges into electric energy by the piezoelectric ceramics installed thereon, and the tuned shunted circuit dissipates the electric energy into thermal energy. At first we clarify the influence that eigenmode of a web panel of a test girder gives structure-borne noise in the test girder. And we test a steel plate which imitated the web panel of the test girder, and compared the results when vibrations were controlled and not controlled. The test results showed effectiveness in vibration control and noise reduction, and indicated that the proposed technique dissipated vibration energy. Furthermore, based on these results, we examined vibration control and noise reduction for the test girder.

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In this paper, we research a conventional evaluation method of soil springs in the dynamic soil-structure interaction analysis of buildings with embedment foundations. First of all, the bottom element and the side elements are decomposed from the embedment foundation and the dynamic interaction characteristics that each element possesses are examined. The estimation method developed by WEN and Fukuwa(2006) are applied to this examination. Based on the above results, it is mentioned that the soil spring of the embedment foundation which is composed with the impedance of both side and bottom elements is overestimated. Finally, we discuss impedance evaluation methods in the limit strength method and the sway-rocking model with embedment.

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In this study, centrifuge model tests have been carried out to evaluate the torsional behavior of pile-supported buildings with the eccentric distance between the center of gravity of the superstructure and the center of rigidity of the piles. Three models were considered; a 9-pile model without eccentricity, an 8-pile model which lacks a corner pile, and a 7-pile model which lacks two corner piles. It was found from the test that the maximum response of the torsional angle of a foundation increases in accordance with the eccentricity which is defined as the same method as the superstructure. The analysis was then carried out to simulate the result of the 7-pile model. In the analysis, a three-dimensional frame model was used, and soil around the piles was modeled as two directional horizontal axial elements and shear springs. A comparison between experimental and analytical results shows a possibility that this numerical model is capable of considering the dynamic torsional behavior of buildings supported by unsymmetrically arrayed piles.

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A critical excitation problem is formulated for a long-span moment-resisting frame subjected to a multi-component base input. The horizontal and vertical ground motions are characterized by a non-stationary model consisting of a given deterministic envelope function and a stochastic function, to be found, obeying a zero-mean Gaussian process. The critical excitation problem is such that, given the power spectra of the horizontal and vertical ground motions, find the worst cross spectrum of the horizontal and vertical inputs which maximizes the mean-squares of the sum of bending moments at the end of the beam under horizontal and vertical inputs. It is shown that the real part (co-spectrum) and the imaginary part (quad-spectrum) of the worst cross spectrum can be obtained by an algorithm including the order interchange of the double maximization procedure for the time and cross-spectrum domains. Numerical examples indicate that the proposed algorithm can work very well. The physical meaning of the critical cross-correlation function is also discussed.

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The energy transmitting boundary used in programs such as FLUSH and ALUSH is a very accurate and useful technique for the earthquake response analysis of the soil-structure interaction systems. However, the analysis is applied only for the linear analysis or the equivalent linear analysis because it can be calculated only in the frequency domain. The author has proposed some transform methods of the frequency dependent impedance to the time domain. In this paper, an earthquake response analysis method for the soil-structure interaction system using the energy transmitting boundary in the time domain is proposed. First, the transform of the transmitting boundary matrices to the time domain using the author's methods is studied. Then, a time history earthquake response analysis is performed using the boundary. Through these analyses, the efficiency and the validity of the proposed method are confirmed.

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An analytical study on the long-term settlement behavior of houses built on the weak clayey ground is reported. To simulate the observed phenomena of the long-term settlement of a few houses quantitatively, the three-dimensional finite element analysis has been carried out. In the analysis, the long-term deformation of saturated clay with the strength increase as consolidation process is considered. Cam-clay model is adopted to simulate the stress-strain characteristics of clay. According to the results obtained by the analysis, it is shown that the observed phenomena can be simulated by the analysis precisely. On the other hand, the reliability of the soil parameters used in the analysis influences the reliability of the predicted settlement strongly. In the latter part of this paper, the settlement of a house on the heterogeneous ground is discussed based on the Monte Carlo simulation. To realize the reliability based design of houses, a fundamental study such as introduced in this paper is indispensable.

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This paper describes the formulation of a three-dimensional elastoplastic analysis for a pile-soil system and its application to an actual in-situ test. In the formulation, the subloading surface model is adopted for the elastoplastic constitutive relation. This model falls within the framework of unconventional plasticity, in which the plastic strain rate due to the stress rate inside the yield surface is taken into consideration. Thus it is capable of describing smooth transition from elastic to plastic state, which is necessary to describe the softening behavior of a soil. In addition, the Mohr-Coulomb model is also adopted, in order to compare with a conventional model in which the interior of the yield surface is assumed to be elastic domain. These constitutive relations have been implemented in a three-dimensional elastoplastic analyses, based on which analyses of lateral loading test of a single pile-soil system were conducted. The results show a fairly good agreement between the analysis and the test for overall deformation behavior of the pile and the soil.

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Three aspects of one-third wall model tests were conducted to demonstrate the stress distribution of studs of light-frame wall under vertical distributed and lateral loads. Analyses with finite element method also conducted to verify the accuracy of numerical simulations employing six analytical modeles. The experimental and analytical results indicate, i) Various analysis models including the model with pin joints predicte in high accuracy the stress distribution of studs under vertical distributed load, ii) Rigidity evaluation of the joint between plywood and stud is important for predicting the lateral displacement of bearing-walls, iii) Various analysis models predict in remarkable accuracy the position and magnitude of the maximum and the minimum stress generated in the wall under lateral load, iv) The analysis model evaluated appropriately the support conditions of the lower part of the bearing-wall predict the stress of studs, bending moments of wall and the inflection point of frame with sufficient accuracy.

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The propose of this study is to validate the seismic safety of the existing full-scale traditional timber temple based on large amplitude horizontal loading test and ambient vibration test. Additionally, evaluation of seismic force-resisting elements and validation of current method for checking the seismic safety of the traditional timber structures are conducted. Ambient vibration tests are conducted at each target story drift in order to evaluate the dynamic characteristics (e.g., natural period, equivalent viscous damping ratio) of both temples Yusho-Ji (Hazu-Cho, Aichi) and Shinpuku-Ji (Arai-Cho, Shizuoka). Seismic safeties of the temples are evaluated by three methods, Allowable stress concept, Energy balance concept, and Calculation of response and limit strength, stipulated in current building code. Finally, non-linear time history analyses are conducted to evaluate the validity of these three methods and figure out the issues

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A lagscrewbolt was developed by third author as a simple and economical moment-resisting connector for glulam constructions. In previous reports, the theory on pull-out capability were developed and verified experimentally. In this report, a beam-column joint using lagscrewbolts were developed, and the design methods were proposed. The joints, composed by a special nut, a steel plate and a special steel connector similar to Japanese traditional wooden connector “Chigiri”, were developed to assemble each member simply on-site and prevent from a brittle failure. As a result, the joint system showed a good performance, and it was agreed with an analytical result.

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Inspection method of wood integrity using distribution of resistance to withdrawal of wood-screw type probes is proposed. The probes have a 5mm length thread and are screwed into wood. Withdrawal resistance of the probes in several depths is measured. Average withdrawal resistance provides integrity of wood. The distribution of withdrawal resistance of wood provides information of degradation in wood. Withdrawal resistance of wood-screw type probes and bending strengths of the specimens are compared. Based on allowable bending stress of wood, critical withdrawal resistance is proposed. Wood integrity is evaluated by comparing measured withdrawal resistance and critical withdrawal resistance.

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This paper aims to investigate the shear strength, which is affected by splitting both failure of the longitudinal re-bars, of R/C columns laterally strengthened with external PC rods. The results of cyclic loading tests indicate that the shear strength is much higher than that of predictions by an existing method based on the combination of truss and arch mechanisms. The shear strength can be predicted better if the effect of cover concrete on the bond stress of longitudinal re-bars required in the truss mechanism is taken into account.

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The objective of this study is to clarify the size effect on the mentioned structural performance of doubly reinforced concrete beams. A total of 16 specimens with four different scales are tested under a four-point-loading. In this experiment, effect of the amount of main reinforcement ratio and web reinforcement ratio on their structural performance is also investigated. Based on the results, it was verified that structural performance in termes of the strength and the deformability of RC beams are greatly influenced by their sizes. Non-linear flexural analysis incorporating Hillerborg's hypothesis was performed. Hillerborg introduced a model including in softening and strain localization of concrete under compression in explaining size effect on ductility.

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This paper proposes new masonry walls using ductile interlocking blocks for retrofitting existing buildings. The presented walls are capable of resisting out-of-plane loads by the interlocking mechanism between blocks. Three 3/10 scale reinforced concrete frames were prepared, and two of them were retrofitted by the walls. Quasi-static loading tests of the specimens were carried out in the in-plane and out-of-plane directions, to compare their seismic performance. Installing the block walls, the strength of retrofitted specimens increased but ductility decreased. Moreover, one of them not only supported axial loads but also exhibited a frictional lateral resistance after failure of the columns.

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This study presents the theoretical solution of bond stress distribution solving fundamental differential equation on bond problem with modeled bond stress - slippage relationship by parabolic curve. The modeled relationship has almost the same shape with previously proposed by the authors considering the equilibrium conditions of bond stress and splitting stress of concrete. By the theoretical bond stress solution, the bond strength is solved by the integration of the bond stress distribution. The previously proposed calculation method using the equivalent bond stress block (EBSB) is verified by the theoretical solution, and the calculated values of bond strength show a good agreement with theoretical ones. The relationship between bond strength and bond fracture energy can be also led by the theoretical solution.

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In beam-to-column welded connection of steel structure, brittle fracture may occur from two or more fracture initiation points, e.g. scallop, end-tab, weld metal and HAZ. As a basic study on the local fracture criteria, the fracture of a steel member that is composed of more than one element, such as a welded joint, is investigated. Fractural experiments on steel elements with notches are carried out, by using two materials that have different fracture toughness. The effects of the notches on the brittle failure and the fractural features of the composition of two different steel materials are comprehended in this paper.

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In this paper, design formulae of RHS-column to beam connections with exterior diaphragms are proposed for exterior columns, where design formulae mean yield strength and ultimate strength. The authors have presented strength calculation formulae for interior columns, and it is possible to derive strength calculation formulae for exterior columns in the same way. For the perpose of comfirming the validity of the formulae, we performed monotonic tensile loading tests for beam-to-column connections. Major findings from the tests are summarized as follows: (1) the calculated values of the yield strength agreed well with the experimental results, (2) although the calculated values of the ultimate strength were about 45∼70% of the experimental results, deformation of column tube walls was not very large.

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The purpose of this study is to investigate the input earthquake energy and the maximum story drift in the hybrid structures based on nonlinear time history analysis. The hybrid structures are composed of different restoring force characteristic components, steel moment frames and light gauge steel house shear walls. In the structure having an origin progress slip hysteresis response, the earthquake input energy and the maximum story drift showed an inversely proportional relationship between f value of the input ground motion. Although the hysteresis responses of the structures are different, the earthquake input energy to the structure have a trend to be determined by the f value of the input ground motion and the maximum story drift of the structure. It mentions that earthquake input energy is influenced significantly by the design base shear ratio. Accordingly, the structure with small ductility reduction factor should have large ultimate strength. The structural response of the hybrid structure, steel moment frame was built in to the light gauge steel house shear wall building, improves the seismic performance by the nature of steel moment frame hysteresis response.

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This paper presents a three-dimensional structural model of an exposed column-base, that take into account bi-axial bending effect. The applicability of this model is confirmed through loading tests and finite-element-analysis on a canti-lever with exposed column-base subjected to bi-directional horizontal forces.
The following observations were made:
1) The model take into account of variation of rotational rigidity due to initial anchor bolt tensioning and axial force of column-base.
2) The model adjust the maximum bending moment capacity and rotational rigidity by changing the line of action of the compressive force line and rigidity modification coefficient.
3) The result from the present model agree closely with loading-test and finite-element-analysis results.

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This paper describes experimental and analytical studies on the fire resistance of a reinforced concrete slab under the positive bending moment. As the result of fire resistance tests, it became clear that a top reinforcement influences greatly the fire resistance of a reinforced concrete slab. The analysis results was well in agreement with the experimental results. Simple appraisal method for the fire resistance of a reinforced concrete slab which allowed the influence of a top reinforcement was proposed. It checked that this appraisal method is able to evaluate the fire resistance of a reinforced concrete slab appropriately.

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