This paper presents the results of series of experimental studies on effects of the type and replacement ratio of fly ash to Portland cement on concrete properties. Type I and type II fly ashes indicated higher water reduction with the increase of replacement ratio up to 70%. Reduction in 28 day compressive strength was smaller for type I fly ash than for type II and type IV fly ashes. Drying shringkage decreased with fly ash addition regardless of type and replacement ratio of fly ash. Carbonation increased with fly ash replacement ratio, and type I fly ash showed higher carbonation. Type I and tpye II fly ashes showed practically no change in durability factor after 300 cycles of freezing and thawing up to 55% replacement, while type IV fly ash showed rapid reduction in durability factor regardless of fly ash replacement ratio.

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The sides and the upper-middle part of the sealed concavity mould were stuck by the water permeability sheets and compacted by using the horizontal vibration. This process can improve the compaction of the upper-middle part which can not gain the good compaction when uses the plywood mould. The voids on the surface of the hardened concrete were evaluated by using the equipment of void analyzer. The good compaction results were determined based on the results of void evaluation. The formula of acceleration and total work were used to give a numerical value to the relationship between the good compaction and the factors of horizontal vibration.

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This paper deals with predictions of drying shrinkage strain of concrete from short-term tests. Two kinds of prediction methods are presented in this study; the simplified method and the extrapolation method proposed by R.P.Ojdrovic and authors, respectively. The ultimate shrinkage of concrete can be predicted with one-point data in the short-term tests by the former method and with the extrapolation of continuous data by the latter one. The effectiveness of these methods was verified with drying shrinkage data accumulated in Japan. The test results showed that both methods, which use the shrinkage data up to 21 days, successfully evaluated the long-term shrinkage strains of concretes. Furthermore, the extrapolation method had higher prediction accuracy than the simplified method especially in the case of the gradual development of shrinkage strains.

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In this study, in order to obtain the prediction equation for expressing the drying shrinkage of concrete with high accuracy, the authors' earlier prediction equation based on composite model is developed from two-phase model into three-phase model, and is extended to the form considering the effects of member size and shape, relative humidity of environment. In addition, for the case of no data concerned with aggregate property, which are input data for the authors' equation, another prediction equation is shown. Furthermore, the proposed prediction equation is discussed in comparison with past data of drying shrinkage.

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In fiber reinforced concrete, fibers are added to improve the brittle fracture of plain concrete. However, the relationship between the fracture behavior of fiber reinforced concrete and the property of fiber is not necessarily grasped. In this paper, in order to investigate the bending fracture behavior of fiber reinforced concrete, an analytical study is carried out by visco-elastoplastic suspension element method (VEPSEM). The fiber element simulated as static elastoplastic element in earlier VEPSEM is modelled as dynamic element in this analysis. It is shown that the analytical results obtained by using this dynamic fiber element can comparatively express the experimental ones. The maximum load becomes high and the descending portion of load-deflection curve becomes ductile. The cause of these results can be explained from the internal cracks occurred by bridging effect of fiber.

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The various factors which affect the investigation and the measurement result about the measuring method of temperature of freshly mixed concrete were examined. As a result, 1. When measuring time is fully able to secure, the measurement result of a bimetal thermometer, a mercury thermometer, and a digital temperature indicator is almost the same. 2. When how to deal with a thermometer is unsuitable, the measurement result of an alcohol thermometer is lower than other thermometers about 1 degree. 3. When the temperature of concrete is measured indoors, measuring time is about 1 minute irrespective of the kind of thermometer. 4. The indoor is suitable as a place which measures the temperature of concrete.

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Floor is the most important part of building, and flatness of floor groundwork strongly influences flatness of floor constructed finishing material. To construct floor groundwork flatly, it is necessary to talk about flatness quantitatively among construction related parties (clients, designers, administrators, craftsmen, etc.). Japan Research Conference of Floor Construction Technology proposed a method to measure and evaluate flatness, by which everyone can easily do on construction site. This report describes the consideration on a validity of this method, and on relations between flatness of floor groundworks and flatness of floors constructed finishing material, based on measurement results in actual buildings.

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Construction records of two high-rise RC buildings were analyzed in detail for rationalization of construction of similar buildings. 1) Based on the actual period of time for each works, the prediction formula of the total duration of construction works for each floor of buildings was established. 2) Employment of members that have a non-structural portion such as PCF should be avoided because it is undesirable from the point of view of both the cost and the global environment. 3) Adoption of the pre-cast concrete members as joint panels of perimeter columns and beams will be the most effective way to reduce the total duration of the construction of high-rise RC buildings with high strength concrete. 4) When the different specified strengths of concrete were used, the effectiveness of adoption of pre-cast concrete members will vary from the place of the adoption. 5) It was confirmed that the adoption of the pre-cast joint panel members could be effective from calculation of the total construction time of the two buildings.

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The purpose of this study is to clarify the construction management on brick masonry buildings completed in Meiji era. The investigation to the document records with the specifications and the wall measurements of an existing building are carried out. The findings are as follows; 1) The estimated size of the bricks was seven point two five sun long, three point five wide, and one point nine five height. 2) The joints among bricks were planned to have the size, zero point two five sun in vertical and zero point zero three in horizontal. 3) The standard procedure in masonry works was suggestive. 4) However the regulations about the size of bricks and the assembling method could not be always found in articles established by the Building and Repairs Section, the strict construction management might be come into force by the highly accurate wall and the rational plan.

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The resistance of membranes to rhizome and root penetration is also important for green roof as well as the other performances for waterproofing. For suitably estimate membranes for this purpose, the actual penetrating force of them to membranes has to make clear. Using the inherent nature of them seeking and growing for moisture, the apparatus for measuring penetrating force was developed. Penetrating forces of rhizome tips of bamboo grass and lawn grass were measured from spring to summer. They increased in a few weeks with periodically swinging in day and night, and the maximum forces of 9.8N and 6N were observed respectively.

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In the present paper, in order to repair slaked lime mortar commonly used for historical masonry structures, the relationships between surface color and water content of mortar, mix proportions, age, mechanical characteristics such as dynamic modulus of elasticity are investigated. It is clarified from the six and half years measurements that there is a comparative correlation between color, water content, mix proportions and mechanical characteristics. It is possible to predict the mix proportions and the dynamic modulus of elasticity of mortar by measuring of its surface color and water content as well as the surface color and the dynamic modulus of elasticity of mortar by mix proportions.

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Solar ultraviolet(UV) radiation is one of major degradation factors for polymeric building materials. Horizontal UV-A (wave range: 315-400 nm) is observed at Choshi and Miyakojima outdoor exposure fields for two years. Hourly UV-A radiation is expressed as a function of solar altitude and global solar energy(wave range: 305-2800 nm). Citing hourly solar radiation observed around Japan for 1991-2000, UV-A radiation is estimated and compiled as database. Yearly/monthly total of UV-A energy maps are showing local difference and seasonal fluctuation. The previous solar UV energy map(1987) by demolished sensor, EKO MS-140 shall be replaced by new one.

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The Onoda Bottle Kiln completed in Meiji era and preserved in Taiheiyo Cement Corporation in Onoda city (former Onoda Cement Corporation) were repaired some times. This paper deals with the transition of quality of fired clay bricks according to every refurbishment. For clarifying the physical properties of bricks, some material testing were carried out, namely a uniaxial compression test, measurements of density and water absorption, the presumption of manufacturing temperature by re-burning of bricks, measurements of moisture movements, porosity and etc. As the production time goes on, the compressive strength was increased, the density became higher, the characteristics against freeze and thaw was not enough but improved, the porosity volume decreased, and the moisture movements were stable and decreased. The potential internal defect was suggested in the brick by press molding. The production temperature is assumed 1150℃ in the brick by cast molding, 1050℃ by press molding , 1250℃ by extrusion molding. Especially the movements of the newest bricks produced by extrusion molding are prominent.

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I propose the derivatives that refund the preparation cost to a building owner unless a specified earthquake occurs. By purchasing the derivatives, the building owner should pay for the earthquake preparedness only when the specified earthquake occurs. Otherwise the additional preparation cost will be repaid. The proposed derivatives are expected to result in the efficient promotion of earthquake preparedness in seismic regions. This paper presents two types of the derivatives: swap and option. In the swap, the building owner is repaid from the option premiums of earthquake derivatives that are accumulated while the specified earthquake does not occur. In the option, by paying an option premium, a building owner will be able to receive the refund when the earthquake does not occur. The option would be effective in the case that the specified earthquake is expected to occur in a high probability. This paper also demonstrates pricing examples of the proposed derivatives utilizing the fundamental knowledge in the field of financial engineering.

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This paper proposes an analysis model of oil damper under extremely small excitation that is modeled based on its mechanism and shows its availability for applying to time history analysis. Under small excitation, with damper stroke as below about 0.5 mm, the damper force becomes linear to the second power of input velocity and the stiffness of oil descends with air bubble in it. Furthermore, friction resistance of packing seal becomes apparent and it depends on its pressure. Considering those characteristics properly, the results of time history analysis with the model follows ones of the experiment.

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We devised flexural deformation response control system, which is response control frame of new general idea, consisted of four elements; the wall located in a center of a building plan (Super Wall), the cantilever located in a building top (Super Beam), the column located at perimeter of a building (Connecting Column) and the control device (Damper). ・We used most basic 3 elements Maxwell type mass point model and clarified a basic principle and a control effect of vibration reduction by flexural deformation response control. ・We carried out elastic vibration analysis in a experimental building model and confirmed a meaningful vibration reduction effect in a practical section of a building. We clarified a structural characteristic about this new response control frame by this paper from the above and showed a thing with utility.

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Prediction technique of strong ground motions has been intensively developed in Japan since the 1995 Hyogo-Ken Nanbu earthquake (M_J 7.3), and it has been applied to the practical prediction for inland earthquakes and plate-boundary earthquakes by Japanese Government. On the other hand, recent earthquakes of the 2001 Geiyo earthquake (M_J 6.4) and the 2004 Mid Niigata prefecture earthquake (M_J 6.8) arose not only requirements of safety of lives and structural elements but also requirements of function of equipments and industrial lines. These requirements are well realized in the performance-based design of structures. Hence, we proposed a method of seismic hazard analysis based on fault rupture scenarios and their occurrence probability for implementation of strong ground motions predicted by fault models in performance-based design of structures.

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We conducted aftershock observations in Chuo Ward, Fukuoka city to make clear reasons why building damage had been concentrated near Kego Fault during the 2005 West off Fukuoka Prefecture earthquake. We found significantly large site amplification in the area limited within a distance of about 200 meters from Kego Fault to the northeast direction. Amplification factors in this area are evaluated to be about 3 times in PGA and PGV, and it corresponds to the increment of about 1 in seismic intensity. It can be interpreted that the amplification is affected by irregular shallow subsurface structure like basin edge effect.

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The influence of hysteretic loops with negative post-yield tangent stiffness and multi-yield characteristics on seismic response of single-degree-of-freedom (SDOF) and multi-degree-of-freedom (MDOF) structures is investigated in this study. The SDOF models, MDOF shear-beam models, and MDOF coupled shear-flexural-beam models with various structural parameters are analyzed for a number of ground motions to identify the trend of structural response. Major findings are 1) SDOF and MDOF shear-beam model have a large probability of crawling collapse once the structure exhibits a negative post-yield tangent stiffness, 2) the change of hysteretic loop with negative slope to multi-yield loop is effective to reduce the maximum story drift particularly for MDOF shear-beam model, and 3) the addition of flexural-beam to the shear-beam is very effective to reduce the maximum story drift and drift concentrations, which diminishes the multi-yield hysteretic loop effects.

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Understanding of dynamic characteristics of building structures is a key issue in the seismic design technology. From this point of view, Building Research Institute (BRI) is operating the strong motion network for buildings since 1957. The BRI annex building is a one of the stations of the BRI strong motion network and densely instrumented with 22 accelerometers. In this paper, variation of dynamic characteristics of the annex building is discussed using strong motion records. Decreasing of fundamental natural frequencies of the annex building with the passage of time is recognized from the optimizing analysis of 158 strong motion records using a single-degree-of-freedom system. 16 records with relatively big displacements are selected in order to examine such phenomena in detail. The Evolution Strategy (ES) is applied to the optimizing analysis using a multi-storey sway-rocking model. ES is a powerful problem-solving tool based on natural evolution. Building stiffness, rocking stiffness, swaying stiffness and building modal damping ratio are targets of the optimization. The rocking stiffness, the swaying stiffness and the modal damping ratio of the building show stable behavior with the passage of time. Consequently, it is confirmed that the decreasing of the natural frequencies is caused by the softening of the building stiffness.

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This paper deals with the large deflection analysis of reinforced concrete slabs considering the effect of bond slip of reinforcement. Johansen's yield-line theory is well known method of calculating the ultimate strength of RC slab. However, it under-estimates the ultimate strength of slabs which have fixed edges because of the membrane stress. In order to take it into account, geometrical nonlinearity should be considered. In this paper, we propose the method of large deflection analysis which is based on Murray and Wilson's method. In order to verify the analytical method, three numerical examples are given and the results are compared with the experimental results.

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In this paper, a finite element technique, of which an unknown quantity is the coordinate value on a deformed body, is applied to analysis of tension structure with geometrical nonlinearity. This procedure belongs to the displacement method though an unknown quantity is not set as the displacement. In this discretization formulation, a cable element and a membrane element are described. The three dimensional coordinate value of the tension structure on the deformed body is obtained directly by this formulation and all the mechanical behavior is grasped. There is a feature which does not need coordinate transformation at all in this formulation when the whole system equation is constructed with element system equations. In the example of the analysis, concerning the tension structure, the numerical result which satisfies the cutting pattern on membrane material and the most suitable equilibrium configuration of the deformed body at the same time is shown. The dynamic response analysis is executed by using the cutting pattern before and after optimization analysis, and the obtained time history responses are compared. Effectiveness and validity of this technique become clear from our formulation and numerical analysis examples.

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Shaking table tests are conducted on soil-pile-structure models to investigate the seismic behaviour of buildings with semi-rigid pile head connections. The dynamic test results show that (1) The semi-rigid pile head connection is effective to reduce bending moment of piles and footing beams; (2) In case of semi-rigid pile head connections, the shear force of pile head at the edge of building tend to increase, when axial force increase; and (3) The maximum acceleration of superstructure with semi-rigid pile head connections is slightly smaller than that of rigid one in this study.

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An evaluation method for post-earthquake settlement of foundation on cohesive ground is proposed. The method is based on a relationship between maximum dynamic shear strains and residual volumetric strains obtained from cyclic shear tests of clay. A dynamic centrifuge test of a structural model with eccentric load on clay was carried out. The test was simulated and evaluated by the proposed method. The settlements evaluated showed good agreement with those measured in the test, which proved the proposed method to be appropriate.

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This paper presents the results of static lateral loading test performed on traditional timber farmhouse in Japan. The aim of this research is to clarify the horizontal load carrying capacity and the failure mode of this type of house by full scale experiment. As a result of the experiment, the maximum horizontal load was 45kN at the deformation angle 1/35 radian. Static analysis using a theoretical model considering the structural performance of joint and deterioration of timber was performed. The results of the analysis are discussed in comparison with those of the experiment.

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Authors proposed a numerical model for the inelastic analysis of three-dimensional frames including L-shaped shear walls in part 1: Constitutive equations. In the present paper, We made the hysteresis model of the slip spring which was one of the plastic elements considered in this numerical model newly, based on our experimental slip data of wall bottoms. Then, we compared the analytical results applying the numerical model to L-shaped shear walls with boundary beams with our experimental data. According to the comparison result, the analysis of the numerical model expresses the main characteristics of L-shaped shear walls sufficiently.

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The purpose of this study confirms that the proposed hysteresis model under multi-axial stress is applicable to the structural member level. The hysteresis behavior of panel-zone web subjected to varying axial stress and shear stress is also evaluated based on one of material level under multi-axial stress in this study. For this purpose, loading tests for panel zone were performed under various loading paths, such as simultaneous loading and sequential loading of axial force and shear force. The numerical analysis of panel zone under multi-axial loads was carried out and the material properties were determined from the proposed hysteresis model under multi-axial stress. Comparing between the numerical analysis and test showed that the proposed hysteresis model under multi-axial stress was applicable to member level. Based on the results of numerical analysis, an experimental investigation on the hysteresis behavior of panel-zone web was performed and compared with that of material test.

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The purpose of this paper is to clarify the statistical properties of member ductility requested to ensure the deformation capacity of steel moment resisting frames considering the uncertainty of member ductility. The drift angles at three different limit states are defined as the deformation capacity. Two types of steel moment resisting frames with the different number of stories are used as analytical frame models. Two types of member restoring force-deformation characteristics are employed in the analytical models. For the analytical models, the load-deformation relations under static horizontal loads are calculated using Monte Carlo simulation and pushover analysis with considering stress-redistribution. Based on the analytical results, this paper proposes relationships between the mean value and the coefficient of variation of member ductility to ensure the deformation capacity.

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The flexural strength of a beam web joint connected to a concrete filled square steel tubular column was calculated by the mechanism method assuming plastic collapse mechanisms of the column flange and the beam web end. This paper presented a calculation formula which was led from the solution obtained by this analysis and the formula was on the basis of the design formula for beam web joint connected to a square tube column which had been already proposed. Furthermore a calculation example was shown by using the formula.

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With regard to moment-resistant frames installed by diagonal braces, the strong axial force is introduced into a column from diagonal braces at a beam-to-column connection. When the column is made of CFT (concrete-filled steel tube), the axial force firstly transferred to the steel tubular portion should transfer to the filled concrete in order to expect the composite action as a CFT. Two types of stress transfer mechanisms may be available in CFT columns. The one is the concrete bond to steel tube, and the other is a mechanical shear key functioned by the cut-through diaphragm for beam-to-column connections. The paper demonstrates the stress transfer capacity by a test of a realistic connection composed of a H-shaped beam, a CFT column and a diagonal brace.

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A sustainable social system has been one of the urgent themes for global environment in the 21st century. In a construction field, the energy saving measure has been discussed much more especially from the viewpoint of building mechanical engineering. It is also important to approach the global environment issues from a structural engineering. The authors propose a new concept "Triple skeleton system" which can be adaptable for change of the social-economy situation and global environment issues. New fully precast concrete slabs (F-PCa slab) are applied in this system in order to remove steel members without damaging them. In this paper, in-plane stiffness and strength, the characteristic of micro tremors, and the creep behavior of F-PCa slabs are investigated.

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