The aim of this study is to improve the freezing and thawing resistance of concrete which is mixed with drying shrinkage reducing agent. The freezing and thawing degradation is caused by advection and diffusion of pore water in the hardened cement paste. Incorporating a hydrophobic compound into the hardened cement paste can prevent the movement of pore water, and thus it improves the degradation resistance due to freezing and thawing. It is found that around 20 μm emulsion, which is a hydrophobic compound, based drying shrinkage reducing agent improve the resistance to freezing and thawing action. Furthermore, the hydrophobic compound-based drying shrinkage reducing agent can be secured more than 60% durability index and least 15% shrinkage reduction ratio. Finally, both the deterioration resistance to freezing and thawing and shrinkage reducing performance is confirmed.

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This research focused on the water absorption behavior in water retentive materials and water permeable materials, by using the neutron radiography technique. The moisture characteristic curve, which is hydraulic diffusivity as a function of volumetric moisture content, was calculated with pore size distribution of the both materials, and an unsteady water diffusion analysis was conducted. The experimentally observed water behaviors by the absorption test were well captured by the diffusion analysis. And also the results showed that the gravity effect for calculation of water movement in the water retentive and permeable materials was considerable in comparably rapid water movement.

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This paper reports on the investigation into the influence of adhesive and tile size on bending properties of tile finishing ALC panels. At first, the influence of adhesive on deformational performance was conducted by the compression and tension test using ALC specimens, finished with various adhesive, of 220 x 100 x 100mm. Then, the bending test was also conducted by using ALC panels, finished with various adhesive and tile, of 2995 x 600 x 100mm.

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In this paper, the authors reconsider to improve the slider in the method of measuring the slipperiness of wet floors with bare feet. First, sensory tests for making psychological scale of slipperiness were carried out with many and various wet floors. Next, they studied on the adaptability of C.S.R'•BF with many and various wet floors by using psychological scale. Then, the new slider of ONO•PPSM (ONO•Portable Pull Slip Meter) was developed, corresponded to psychological scales. Finally, the relation between a measured value (C.S.R'•BF 2) with the new slider of ONO•PPSM and the evaluation scales were presented as the evaluation indexes.

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Some fundamental properties are disclosed on eigenvibration and damping in connected building structures. A classification in terms of damping variation properties with respect to increased capacity of connected dampers is conducted by using complex eigenvibration analysis. There exist several regions in the plane of mass ratio and stiffness ratio. In each region, the lowest-mode damping variation exhibits a different property with respect to increased capacity of connected dampers. These properties are useful in the design of the system of connected buildings.

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We develop an envelope model at the seismic bedrock of acceleration ground motions for stochastic Green's function method using records of medium-sized earthquakes in the source region of the 2008 Iwate-Miyagi Nairiku earthquake. The envelope is modeled based on the multiple forward scattering theory. The estimated randomness was larger than that for subduction-zone earthquakes in previous studies and so the envelope was wider than that for subduction-zone earthquakes. Boore's model used in previous stochastic Green's function method for the crustal earthquake underestimates the duration and attenuation of peak ground acceleration. On the other hand our proposed model improved these problems.

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This paper focuses on the horizontal bidirectional mechanical properties of low-modulus G0.35 type high-damping rubber bearings. Tests of reduced-scale bearings were conducted to identify the mechanical properties of the bearings. The influence of bidirectional loading was strongly apparent in the measured hysteresis properties. A refinement to an existing analytical model was provided to predict the mechanical behavior of a wide variety of high-damping rubber bearings. Additional shear strain due to twist deformation was included to evaluate shear stress components in the bearing. Seismic response analyses were performed to evaluate the dynamic behavior of an isolated building under bidirectional earthquake excitations.

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Seismic intensity scales for long-period ground motions are proposed as indices calculated from acceleration time histories filtered with the adequate frequency characteristics to fit human perception. The indices are investigated based on the correlation with maximum responses of high-rise buildings. We find that the proposed seismic intensity scales of long-period ground motions are highly correlated to the maximum story drift of high-rise buildings derived from both observation data during the 2011 Tohoku-oki earthquake and simulation results of the Nankai trough megathrust earthquake, and are effective indices of long-period ground motions for earthquake disaster prevention. The maximum absolute velocity response spectrum (1.6-7.8s) used for the JMA's rank classification of long-period ground motions is also investigated by comparison to the proposed long-period indices. The cumulative plastic deformation ratio of girders is also an important structural response of high-rise buildings related to their damage due to duration, and is found to be closely correlated to energy spectrum near their dominant period rather than other long-period indices.

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[in Japanese]

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This study examined the applicability of ecocement for circumference fixation liquid and foot protection liquid of pile using ecocement. The main conclusions of this study are as follows.
1. The compressive strength of the cement milk using ecocement becomes a higher than the compressive strength using normal cement in materials aged one weeks, however, it is almost the same in materials age four weeks.
2. When ecocement is used as circumference fixation liquid, the ratio of sand and clay largely affects the compressive strength.
3. The compressive strength of materials aged 28 days is found by comparing the compressive strength of materials aged 3 days.

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The aim of this paper is to examine the shear resistance mechanism of seismic retrofitting by external reinforcement，which consist of divided thin steel plates and continuous fiber sheets with grout mortar layer，for existing RC short columns．This paper mainly describes the shear effectiveness by the ribs of steel plates in a short columns．In order to investigate the above objects，lateral loading tests were conducted for the six specimens with two types of fiber sheets，with different of ribs width and the steel materials．The test results show that this method is very effective in enhancing the shear strength by ribs of providing steel plates，and a shear resistance which consists of elements of a lateral ribs and fiber sheet was supposed．Based on these results，the study indicates that the shear capacity can be estimated using the design guideline for ultimate shear strength issued by AIJ in 1990.

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Cracking behaviors of reinforced concrete beams induced by expansion corrosion products around corroded longitudinal bar was investigated using accelerated corrosion tests and finite element analysis. The effect of confinement by means of transverse bars was evaluated using bond-slip interaction between bar and concrete. The effect of concrete strength associated with distribution of porosity of cement paste and corrosion rate distribution due to the bar location were also evaluated using different expansion ratio and pressures respectively. The test and analysis results indicate that concrete strength and bond-slip interaction significantly influence the prediction of crack width and transverse bar stress, and that the cover crack propagation is influenced by corrosion rate distribution.

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This paper presents results of full-scale cyclic loading tests of moment connection under constant deformation amplitude conducted to evaluate deformation capacity. The effects of beam section size and of weld access hole are investigated by four type specimens. The relationships between ductility amplitude of beam rotation, cumulative plastic deformation and crack propagation at weld joint are quantitatively obtained from test result. The effects of beam section size and connection detail on crack initiation charactaristic are investigated from stress and strain by FEM analysis.

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This paper presents a numerical study on the effect of lateral bracing with load-carrying capacity for beams subjected to cyclic loading, and proposes a new lateral bracing arrangement method. The current Japanese standard adopts two lateral bracing methods with load-carrying capacity. One is the method to locate lateral bracings equally, the other is to locate lateral bracings near the plastic hinge first and brace the remainder of the beam according to allowable stress requirements. In the proposed method, lateral bracings are located at the position with beam-ends and the remainder as equal distance of l_b/i_y≤100.

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