This paper deals with the influence of the eccentric loading in the compressive strength test of high-strength concrete. In the experiment, five kinds of concretes (water binder ratio is 65% to 20%) were examined. The range of eccentric distance is 0 mm to 9 mm. Conclusions are as follows. (1) The influence of eccentric loading becomes large as concrete becomes more high-strength. (2) The experimental result of (1) can be presumed based on vertical strain of specimen. (3) The compressive strength test result in the tolerance level of JIS A 1108(within 1mm) becomes almost equivalent. (4) Under eccentric loading, the horizontal strain of the upper part of specimen became small. This result has suggested increasing the restraint of the upper part of specimen under eccentric loading.

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Integrity of the tile finish on existing buildings is usually evaluated by the investigation of the exfoliation area and bond strength test. However, exfoliation sometimes occur again within the wall evaluated healthy by investigation. Therefore, we propose a method to assess the possibility of future exfoliation by measurement of the strain of existing wall tiles. The strain can be measured by strain gauges were affixed to the surface of the tile to be stripped. The results of the indoor and outdoor environmental test have confirmed that strain in bonded tiles can be estimated by the proposed test method.

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Seismic observation on an actual base-isolated hospital building has been conducted with dense sensors setup of acceleration and earth pressure to evaluate lateral seismic earth pressure acting on an embedded foundation during the earthquake. In this paper we analyze characteristic and mechanism of the lateral seismic earth pressure based on observed data on low and medium-level earthquake response. It is clearly shown that the lateral seismic earth pressure acting on the embedded foundation is closely correlated with the relative displacement between soil and foundation. Impedance function of the foundation is also evaluated by transfer function between lateral seismic earth pressure and relative displacement of soil and foundation. The estimated impedance described in this paper may be of help to the engineers to choose suitable characteristics of impedance for their design when considering the interaction effect between the soil and the structure.

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Source model composed of four strong motion generation areas (SMGAs) of the 2011 off the pacific coast of Tohoku earthquake (Mw9.0) is estimated by the empirical Green's function method. We also estimate the short period spectral level of interplate earthquakes (Mw6.0 to Mw7.8) in the Pacific plate including the aftershocks and foreshocks by the spectral inversion method. It is found that the short period spectral level of the main shock calculated from the estimated source model is consistent with the empirical scaling estimated in our previous study and this study for interplate earthquakes (Mw6.5 to Mw8.2). The SMGAs are located at deeper positions and are different from large slip areas. The total area SMGAs of the main shock is consistent with the empirical scaling in our previous study for interplate earthquakes (Mw 7.1 to Mw 8.2), but is much smaller than the empirical total area of asperities derived by Murotani et al..

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When both a building and its equipment have a vibration controller, an equipment's controller should consider the behavior of a building. First control schemes are classified according to the amount of state variables communicated between the controllers and type of control objectives. Then, a high-rise building with an elevator system under seismic excitation is analyzed to compare the performance of the classified schemes that uses the linear quadratic regulator. It is observed that the story drift and the response of elevator rope can be reduced sufficiently even if all the state variables are not communicated.

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A simultaneous optimization procedure is formulated in order to match desired performances of a building. Design variables of structural and control parts of a building with a linear quadratic regulator (LQR) controller are optimized simultaneously. The natural period and the damping factor of the LQR-controlled system are calculated based on eigenvalue analysis. Design response spectra are used to consider input ground motion and to calculate the maximum control force as well as maximum responses. As an example, this optimization procedure is applied to the seismic strengthening of a traditional wooden building by considering reduction of its displacement and acceleration responses.

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The cement treated soil is going to be applied to prevent the liquefaction or to increase in the bearing capacity of pile. There are four characteristics in the cement treated soil: 1) The strength of the cement treated soil is larger than that of the conventional soil, and is smaller than one of the concrete. 2) The nonlinear behavior can be seen adjacent to the peak strength. 3) After the peak, the softening occurs. 4) The expansion strength is found while the soil is not in general. In this study, subloading surface model introduced by Prof. Hashiguchi is incorporated into Mohr Coulomb Criteria. The undrained triaxial compression tests of cement treated soil were performed under the 0.1 and 0.4 MPa constrained pressure. The parameters were fitted by the result derived by the comparison between experiment and numerical simulation. Using that parameter, the splitting tests were performed. The numerical results showed good agreement with the experiment data about the expansion strength. However, further investigation is required to simulate the splitting test, such as a deformation characteristic. It is assumed as the tasks for the future.

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In recent inland shallow earthquakes, pulse-like ground motions have been observed which caused severe damage to wooden buildings. In this study, we propose the formula to estimate the maximum response of wooden buildings for pulse-like ground motions, which is idealized as a sinusoidal pulse, by response spectra method. The accuracy of the approximation by a sinusoidal pulse is examined, compared with the observed record of recent inland shallow earthquakes. The accuracy of the formula is examined, compared with the result of dynamic time history response analysis and shaking table tests. In addition, the required seismic performance of wooden buildings for a sinusoidal pulse is examined.

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This paper reports the results of the analysis for traditional wooden houses at Kotagede near Yogyakarta which damaged by 2006 Central Java Earthquake based on field survey, static loading test for mock test frames and evaluation of seismic motion intensity. Major findings are as follows: (1) In the field survey, structural and vibration characteristics are clarified. (2) In the experiment, horizontal resistance force is influenced by beam-to-column joint specifications. (3) Using proposed modeling method for the traditional frameworks, earthquake motion intensity at Kotagede is estimated at PGA=250cm/s² based on the seismic performance evaluation of damaged houses.

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This paper proposes an evaluation method on material characteristics for the column-to-beam (Sashigamoi) joint in traditional wooden structures based on static loading test for mock test frames and pull-out tests of joints. Major findings from the research are as follows: (1) In static loading tests, the amount of beam's movement are clarified. (2) In the pull-out tests of joints, new failure modes and failure progress patterns are classified. (3) We revised evaluate equation of yield force and initial stiffness for cotter pin joint, and constructed new equation for nose pin joint based on AIJ's one.

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This study researches how stress concentration has an effect on cyclic behavior of H-shaped beam with web perforation made of high strength steel “H-SA700”. It is examined and compared with the same shaped beam made of “SN400” by cyclic loading tests. Cyclic elastic deformation of H-SA700 increases even under constant-amplitude cyclic loading. This property may amplify the local plasticity near a circular hole. So new yield strength, Q_c and Q_F, by means of elastic theory of stress concentration, are suggested. Q_c is a minimum strength when somewehre in a hole edge will be plastic. Similarly Q_F is a minimum strength in a minimum section. In addition large deformation behavior of H-SA700 is shown.

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For E-Defense project, it was shown that the soft story mechanism on 1^st story occurred when the 4 story steel moment resisting frame with fixed base column was subjected to huge seismic force. To prevent the plastic collapse of the column on 1^st story, our previous paper suggested the new column support system on 1^st story, which consist of the reinforced concrete downside column and the steel topside column. In this paper, the fishbone-shaped frames are applied to estimate the damage distribution and the collapse deformation capacity of the steel moment resisting frames with these support systems, and the column and beam demands to keep the columns elastic are clarified.

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In the previous papers, when slender steel piles beneath buildings experience high axial compression forces as a result of vertical loads increased by P-Δ effects with inertia forces acting on the buildings and then the soil liquefies, buckling of the piles occurred even though they are restrained laterally by the liquefied soil. In the real structures, the pile is subjected to the lateral and axial force during earthquake. This paper estimates the ultimate strength of slender piles in liquefied soil when steel pile subjected to vertical and horizontal load. The relationship between the axial force and the flexural moment of the slender piles and the soil-pile interaction is presented.

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A company which has a production facility has a strong concern for early business recovery after a natural disaster. Though the “Recovery Time Objective” (RTO) is very important to carry out business continuity management, a method to predict restoration time which is necessary to decide RTO has not been established. This paper proposes two simplified methods applying the idea of an event tree analysis for productive facilities. However event tree calculation becomes difficult when the number of events is larger. Commonly used PC programs cannot do the calculation which involves over thirty events. The event tree analysis for over thirty events is able to be calculated by the restoration time evaluation of a series of scenario simplified. This paper shows the derivation of the methods, the calculation accuracy and the validity of the methods. Finally a calculation example to which these proposing methods are applied to an assumption factory is introduced. It is found that recovery time does not become short though the number of restoration staffs is larger because of influence of other factors like approval time and delivery time.

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The characteristic formula of viscous damper force is often the nonlinear viscous element model in seismic time history response analyses of structures having the dampers, but it is not always accurate. Damping force depends on properties of viscous material and its components, but the formula is not compounded from them. To make the formula more correct, the previous thesis had demonstrated some viscous material characteristics with detailed experiments. It indicated that viscous force depended on strains and frequencies, and its hysteresis loop was like that of viscoelastic in small strains. This paper shows modeling of viscous material properties with viscoelastic theories that are fractional derivative and mechanical elements models.

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