This paper presents the results of series of experimental studies on effects of compressive strength development of eco-cement concrete. In early stages, eco-cement concrete increased the strength development than ordinary cement concrete. At a long term, however, it did not increase. Compressive strength of eco-cement concrete was smaller than the same water-cement ratio of ordinary cement concrete. Influence of curing temperature was the largest at the age of 7 days, while at the age of 28 days, it was not confirmed. Furthermore, this paper proposes new standards from the above results. An addition taking into account the discrepancy between the strength of the concrete in the structure and the strength of specimens (ΔF), temperature compensated specified strength T, and time for formwork to remain in place.

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The effects of high temperature on the mechanical properties of moderate strength concrete (MSC) have been studied experimentally at various temperatures that covered the 20℃ and the 100 to 800℃ temperature range at 100℃ increments. Concrete specimens of MSC were tested under compression at ages about 14 years. The stress-strain curve under compression test shows that MSC exhibits brittle properties below 500℃, and ductile properties above 500℃. The compressive strength decreases below 100℃ during heating, increases up to about the same strength of room temperature below 200℃ and gradually decreases with further increase of temperature. From these test results (including Ref.9 test results), mathematical expressions of the compressive strength, the strain at compressive strength, the stress-strain relationship and the modulus of elasticity were proposed. The comparatively good correlation between predicted and experimental results indicates the adequacy of the expression of stress-strain relationship.

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This study aims at experimentally clarifying relationship between mechanical property and damage in concrete exposed to high temperature and low humidity environment. The degree of damage in concrete is evaluated in terms of mercury intrusion porosimetry (MIP) and X-ray radiography, which potentially quantify micro-crack nucleation. In experiment, concrete was exposed to environments in combination of three temperature levels (20, 50, and 70 degree), and three relative humidity levels (30, 60, and 100%). After this exposure, mechanical properties and micro-crack nucleation degree in concrete were measured in comparison with non-exposed concrete in reference. As a result, mechanical properties were decreased by 20% at most. Finally it was found that test results both in MIP and X-ray radiography successfully correlate damage degree in concrete and mechanical property variation.

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As for water tightness of cracked concrete, focusing on its surface roughness, we experimentally studied in the case of both variable crack width and constant one. As a result, we found that fractal dimension, which showed a strong correlation with the compressive strength as cracking, could be presumed from strength properties and be a parameter to evaluate the surface roughness. Moreover, it was shown that the factors of flow resistance, such as length of flow, area of flow, and surface roughness, had the most effect on causing much difference in the value of water permeability between an experimental value and a theoretical one.

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This paper proposes methods to prevent tile facings from falling off external walls. The methods introduce the concept of performance design for tile facings on external walls. In this paper, the specifications for tile facings are evaluated using the deformational performance test, and the allowable strain is obtained. The design strain is predicted from the deferential movement that develops in the tile facings on external walls. Finally, both are compared and the safety is confirmed. The safety provided by the specifications for the tile facings was verified by a trial design, and the validity of the proposed method was verified by actual performance on a building.

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In this study, a computer-controlled, automated artificial test apparatus was developed that permitted subjecting sealant products to a deterioration process that was similar to that of outdoor exposure. Three kinds of sealant product were selected. Outdoor environmental data was collected over a one year period that included, joint movement-of the automated outdoor exposure test rig and specific weathering factors such as the temperature of sealant, quantity of solar radiation and rainfall. As a result, the movement, temperature, total radiation and wetting conditions of the indoor test were nominally the same as those extracted from the outdoor test with the exception of the wavelength distribution for solar radiation. Comparing results of the deterioration of sealant after one year of testing, the indoor test apparatus proved to offer a high degree of correlation to results obtained in the outdoor test for sealant products MS-1 and MS-2. The results suggest that the development of the proposed indoor test using the automated artificial test apparatus appears promising given the degree to which results can reproduce those obtained from ageing sealant products outdoors.

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For designing a safer mechanically anchored waterproofing membrane system against tyohoons, the type and mechanical property of waterproofing membranes are the critical factors of the system. In this study, the wind tunnel test with various mechanically anchored waterproofing membranes was carried out to gain an understanding of the behavior of waterproofing membranes and its relation to wind parameters against high wind speed. Three types of full-scale size waterproofing membranes were exposed to high wind speed. All membranes were lifted up by negative pressure of wind and tensile force induced in a fastener. The billowing condition of waterproofing membranes depended on their modulus and the strain was greater at the bias direction of fastener. The modulus of waterproofing membrane exerted an influence upon the frequency and fluttering patterns. It is necessary to consider the mechanical property of waterproofing membranes when the waterproofing membrane system was designed against high wind speed.

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Small-sized core method by sodium gluconate can be used in determining the unit cement content of concrete.Applicability of this method to quality control of concrete in structures was examined.A full-scale model structure with a high fluidity concrete, whose extent of segregation was intentionally increased, were built and relationship between concrete quality and the unit cement content determined with the small-sized core method by sodium gluconate was studied.It was shown that the relationship was correlative and application of small-sized core method by sodium gluconate to the quality control of concrete in structures was found to be reasonable.

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Bond of repair materials to deteriorated RC structures is of importance in the application of patch repair materials. Compression-shear and tension-shear bond tests were carried out to obtain bond failure envelope in consideration of every stress condition between repair materials and substrate. In the case of the compression-shear bond test, bond strength is quite affected by strength of base materials (repair material or substrate), because rough surface of substrate heighten internal friction angle and strength of interface between repair material and substrate become higher than those of base materials. However, in the tension-shear bond test, polymer cement ratio (P/C), water absorption and roughness of substrates are ultimate trigger for bond strength. Consequently, the guideline for selecting appropriate repair materials was proposed on the basis of the test results.

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Wood is well used in construction field and a great deal of demolition wood is discharged in Japan. Since the recycling rate of wood is said to be inferior to other material, such as concrete, it is necessary to develop and construct a new system for recycling of demolition wood. However, it is difficult to obtain reliable information on demolition wood because demolition works are conducted by a lot of small companies, especially for wooden houses. In this report, it was investigated the enforcement condition of the "Construction Material Recycling Law" in a city region, and the estimated amount and source of demolition wood using the notification for "the Construction Material Recycling Law." The obtained results are summarized as follows: 1. The largest source of construction wood waste was demolition works of wooden isolated houses. 2. The values of 0.21m^3/m^2 and 0.004t/m^2/year for wood were estimated to be discharged from wooden isolated houses. 3. The average age of demolished wooden isolated houses was 34.4 years, and more than half of demolished wooden isolated houses seemed to keep in a good condition.

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The in-service period of residential houses are too short compared with the return period of earthquakes. Therefore, it is necessary to consider aged deterioration when we measure the effectiveness of seismic retrofit or maintenance against plate boundary earthquakes such as the Nankai earthquake or inland earthquake to occur in several decades. This paper presents a method for predicting earthquake damage probability of wood houses considering aged deterioration affected by biodeterioration and maintenance status. To demonstrate the validity of the proposed method, the damage probability for scenario earthquakes in the Nankai earthquake or inland earthquakes by assuming the oceurrence 25 years later and we discuss how to prepare for these earthquakes.

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The response of foundation during earthquakes is referred to as an effective input motion (EIM). It expresses total interaction effects during earthquakes. This paper discusses what will be an appropriate measure to evaluate the EIM based on obseved earthquake motions. The main conclusions obtained in this study can be summarized as follows. (1) A measure for the EIM, which is defined as a ratio of square root of the integrated squared-motions, has shown close relation to a transfer function of the system, (2) The measure for EIM corresponding to equivalent predominant frequencies of the ground motions fits well to the transfer function estimated from observed records. (3) The component of kinematic interaction is predominant in lower frequencies and the effect of inertial interaction becomes comparable in magnitude to kinematic interaction with increase of frequency.

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Equations for evaluating the time history responses of the story shear and story drift of multi-story regular-shaped buildings had been proposed by one of the authors. The applicability of the proposed equations to multi-story irregular-shaped buildings consisting of mixed soft and rigid stories in which the story collapse mechanism is formed under earthquake motions was investigated in this study. This paper shows that the equation for the story shear response is applicable to the irregular-shaped buildings. On the other hand, the prediction accuracy of the story drift response by the proposed equation for the irregular-shaped buildings is less than that for the regular-shaped buildings, because the variation of higher vibration modes in the irregular-shaped buildings is larger than that in the regular-shaped buildings. Then, an equation for evaluating the time history responses of the story drift considering the effect of the variation of higher vibration modes is proposed.

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A technique for empirically estimating non-stationary site effects in time domain is proposed by ingeniously averaging out the wavelet coefficients to improve Birgoren and Irikura procedure (2005). They developed a method for estimating site effects in amplification and phase using the Meyer-Yamada wavelet. An advantage of the method is an equalization of the wavelet coefficients for multiple seismic records. However, it requires accurately synchronized records. In this study, an automated phase identification algorithm to synchronize the S-wave phases is proposed. The applicability of the proposed method is demonstrated for the observed seismic records.

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Vibration tests of a structure supported on 25-piles have been conducted at a large-scale mining site. Ground motions from large-scale blasting operations were used as excitation forces for vibration tests. The pile-supported structure was constructed in an excavated 4m-deep pit. The test pit was carefully backfilled with sand to create uniform test bed. Accelerations were measured at the structures, in the sand of the test pit and in the adjacent free field. Strains of piles were also measured. As the level of the input motions increased, response characteristics of the structure were remarkably changed by nonlinear soil around piles. This paper shows vibration tests results and its simulation analyses, and discusses nonlinear behaviors of structure supported on pile-groups.

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An analytical solution is presented to predict the sloshing response of a cylindrical liquid storage tank with a single-deck type floating roof under seismic excitation. The floating roof is considered to be composed of an inner deck stiffened with outer and center pontoons. The deck is idealized as an isotropic elastic plate with uniform stiffness and mass, while the outer and center pontoons are modeled as an elastic curved beam and a rigid circular plate, respectively. The contained liquid is assumed to be inviscid, incompressible and irrotational. The dynamic interaction between the floating roof and the liquid is taken into account exactly within the framework of linear potential theory. By expanding the response of the coupled deck-pontoon system into free vibration modes in air and employing the Fourier-Bessel expansion technique in cylindrical coordinates, the solution is obtained in an explicit form which will be useful for parametric understanding of the sloshing behavior and preliminary study in the early design stage. Numerical results are provided to investigate the effect of the presence of the center pontoon on the sloshing response of the floating roof.

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Analyses of a single pile, a pile group and a piled raft in a homogenous elastic ground subjected to earthquake are carried out using FEM and a simplified analysis method, In the FEM analyses, the raft and the piles are modelled by solid elements, or the raft is modelled by the thin plate elements and the piles are modelled by beam elements. As a simplified analysis method, a three-dimensional dynamic analysis of piled raft foundations subjected to earthquake using a hybrid model is proposed in this paper. In the analysis, the flexible raft and the pile are modelled as thin plates and beam elements, respectively. The soil is treated as springs and dashpots. The results from different modelling are compared, in order to investigate adequate modelling of raft, pile and ground and to investigate dynamic responses of the pile foundations. It is shown from the analyses that horizontal displacements and horizontal accelerations are not influenced by methods of modelling. In contrast, vertical responses such as vertical displacements hence the rocking motion of the pile, axial forces of the pile are influenced by methods of modelling, although the vertical responses are much smaller than the horizontal responses. Details of the results of the analyses are presented, and suggestions for the improvement of the simplified analysis method are discussed.

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A series of vertical load tests are performed on enlarged base bulbs of buried pile embedded in a large soil chamber to investigate the behavior of the pile base under vertical load until the ultimate condition. To measure axial load distribution in the pile a set of strain gages are installed at the top and the bottom of 114mm diameter double steel tube modeling a precast concrete pile. The effects of the size and the shape of the bulb consisting of soil cement are investigated to find the optimum configurations of the bulb. After the load test the base bulbs are excavated to examine the fracture pattern. It is found that the load carrying performance after full mobilization of friction between the pile shaft and the bulb depends deeply on the length of the bulb below the pile base.

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To evaluate a vertical permeability of the ground, the new method for in-situ measuring in a single bore hole is proposed. At first, the soil column of 1m height is taken in the apparatus including a pump and pressure transducers. Next, a permeability test is performed at the underground depth of 20m. In the soil column, a simple flow is occurred in vertical direction. So a vertical permeability is calculated with one dimensional seepage equation using measurements of flow rate and water pressure. The new method is verified by FEM analysis and in-situ test.

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This paper deals with the equilibrium relationship of bending moments acting on column and restoring force characteristics due to column rocking of traditional wooden frames. From shaking table tests and static lateral loading tests, the interaction between column and bracket complexes or pillow blocks on the top of column and the ambulatory movement of column on the base stone were investigated. The equilibrium relationship between the total restoring force and the sum of the bending moments acting on the column is established. By using this relationship, the restoring force due to column rocking can be estimated. In the total restoring force of traditional wooden frame, the restoring force due to column rocking is distinguished when the frame deformation is small. The restoring force from the bending moments at the column-tie beam joints becomes dominant as the deformation increases. By the collaboration between the restoring forces from the column rocking and the bending moments at the beam joints, the traditional wooden frame demonstrates large flexibility and deformability.

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Passive control schemes to mitigate seismic damage of wood houses are discussed. Extensive shaking table tests are conducted for various full-size wood-frame specimens. This paper focuses on the specimens with velocity-dependent dampers, and compares their dynamic properties and performance with those of conventional wood frame as well as passively controlled frame utilizing deformation-dependent dampers. Dynamic properties are defined by equivalent periods and damping ratios. Performance is assessed by referring to story drifts, accelerations, base shear forces, damper deformations and forces, and connection deformations. Test results are also predicted by proposed simplified rules based on the dynamic properties and response spectra.

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Joint probability density function (JDF) for non-normal random variables was derived by bivariate normal distribution function. From this JDF, the referenced strength, the 5th percentile of the strength distribution with 75% confidence level, for each grade of stress graded lumbers was calculated, assuming modulus of elasticity (MOE) as Normal distribution and modulus of rapture (MOR) as 2P Weibull distribution. And the referenced strength was also calculated by Monte Carlo simulation using linear regression analysis by weighted residue (LRA). These values were compared. The results are as follows. (1) The difference between these values depends on species. For example, in Douglas-fir and Dahurian larch they are relatively similar because the standard error by LRA of these species is relatively large. But for some species having small standard error, the difference is relatively large. (2) In lower grades than mean MOE, the referenced strength by LRA method is larger than that by JDF method, but in higher grades the situation is reverse. The reason is that the standard error is proportional to √<MOE> and the standard deviation of MOR in lower grades is small and that in higher grades is large. JDF method is really true from the probabilistic and statistical point. So it is hoped to recalculate load and resistance factors for stress graded lumbers in the Recommendation for Limit State Design of Timber Structures(draft) by JDF method.

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In case of high rise reinforced concrete (RC) buildings it is effective to resist the large percentage of the seismic forces by coupled shear walls with short span beams at the core of floor plans. By this structural system it is possible to decrease the number of columns and beams providing large spaces for use. In order to build this structural system effectively, the short span beams should have high strength, large deformation capacity and damping capacity. And for this type of RC short span beams, it is effective to arrange longitudinal reinforcements diagonally. Cyclic loading tests of 16 specimens were carried out to clarify the seismic performances of short span coupling beams of which all the longitudinal reinforcements are diagonally assembled. Based on the test results, evaluation methods are proposed for the structural characteristics of the beams such as flexural strength, yielding deformation, deformation capacity and hysteretic damping.

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Seismic performances of steel-framed housings are secured by bearing-wall panels composed of wooden panels or gypsum board with light steel members of 1.0mm thick, fabricated by screw bolts. Their hysteretic characteristics have been tested and modeled for time-history analyses, however, their damping values with finishing against large deformation zones are yet clarified. In this paper, real-size dynamic test of bearing walls are carried out, and their damping performances with finishing and visco-elastic dampers are verified. Their performances are discussed on 3 or 4 story steel-framed housing structures, followed by proposing easy damage evaluation method.

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Damages in plant facilities caused by natural disaster such as big earthquake could leads to catastrophic disaster such as fire or leakage of hazardous substances, which might have serious impacts on neighboring residents and society, and impair significantly the credibility of the plant owner. From the viewpoint of CSR (Corporate Social Responsibility), the implementation of seismic countermeasures for seismic upgrading of the plant facilities increases rapidly in number. However, if the level of seismic upgrading of facilities exceeds a critical limit, in such cases, it is sometimes difficult to propose the countermeasures using original structures and existing spaces around them. In this study, the procedure of seismic risk mitigation focused on operation of facility under control of volume of contents is proposed. Then a flat-bottomed cylindrical tank of a refinery is selected as a sample, and the proposed framework of this procedure that combines the method of seismic upgrading and control of volume of contents is applied to the tank to show its usefulness of this procedure.

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The present paper focuses on structural fire resistance of heated steel columns, in particular the columns subjected to thermal elongations of adjacent beams at fires. Behavior of the steel column at the fire is minutely investigated by making full use of a refined finite element analysis taken a 3-D non-1inear thin plate element into account. From results obtained by numerically parametric calculations, it is clarified that the above thermal elongation is not a sensitive factor affected the fire resistance of the steel column and its ultimate temperature can be estimated by verification methods which has been proposed in Recommendation for Fire Resistant Design of Steel Structures (AIJ, 1999).

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