The effective utilization of fly ash is positively studied in various fields and the utilization as raw material of concrete aggregate is one of the effective solutions. So far, the investigation of artificial lightweight aggregate made of fly ash has been carried out and some were put to practical use, but all of them are the foaming type aggregate. Now, different from such foaming type aggregate, "High Strength Artificial Aggregate" (hereinafter called FA aggregate) which has a dense structure through properly controlled production condition has been developed. In this report, the fundamental characteristics test of concrete which was carried out on concrete using FA aggregate made of fly ash as main raw material and with a water/cement ratio of 25 to 60% is discussed centering the comparison with those of concrete using natural aggregate (hereinafter called NA aggregate) and artificial lightweight aggregate in the market (hereinafter LA aggregate). The characteristics of fresh concrete and hardened concrete using FA aggregate have been studied based on the basic tests and following results are obtained. 1. The unit water content of the concrete using FA aggregate in case of ordinary strength region with AE agent tends to be smaller than those of the concrete using NA aggregate and LA aggregate. The workability of the concrete using FA aggregate is good as the same with those of the concrete using NA aggregate and LA aggregate. 2. As to the development of compressive strength of the concrete using FA aggregate, even in the high strength region exceeding 60N/mm^2. to say nothing of in the ordinary strength region, the same level of value with that of the concrete using NA aggregate is confirmed.

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Fatigue resistance of straight area in sealed joint design has been mainly evaluated, but there is a lot of cross area of sealed joint in actual building. Fatigue resistance of sealant to shear movement at cross area of sealed joint was studied experimentally and analytically. Three kinds of sealant were evaluated. The cross joint specimen and straight joint one were repeatedly deformed by shear movement. As a result, the cracks appeared at corner area earlier than the straight area. Moreover, it was shown that the stress of sealant was concentrated at corner area by using the finite element analysis. It was made clear that corner area of sealed joint provided lower shear fatigue resistance than the straight area of it.

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It is important to maximize the design life of buildings in response to the increasing awareness of environmental issues. Consequently, there is now a demand for the aesthetic qualities of buildings to be maintained for a long period. The purpose of this study is to examine the relationship between the color properties of brickwork and the subjective evaluation of age and other visual qualities. The influence of color coordination on aging and desirability is clarified through the results of sensory tests and systematized for the long-term management of building facades.

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Grouting of epoxy resin is a common technique to repair cracks in concrete components. In this paper, test methods for evaluating fatigue resistance of repaired zone of them to movement was studied. First, movements of cracks which had been repaired by epoxy resin were measured in an actual concrete wall and an actual beam. Considering the observed movements, a fatigue machine that produce the similar simplified movements to those and an apparatus for monitoring fatigue of the specimen injection epoxy resin was developed. The results shows repaired zone of specimens were ruptured by repetition of movement even though such a small movement as 2 μ m.

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In our former papers, the mitigation of the across-wind responses of the high-rise building was confirmed. Next, we discuss that the along-wind oscillations have to be considered for the high-rise building with the hysteretic damper. When we consider the along-wind oscillations of the high-rise building with the hysteretic damper, it is an important point that the external wind forces have the mean component continuously. So we need to discuss the influence of mean and fluctuate components on the responses of the high-rise building with the hysteretic damper. In this paper, we show the along-wind oscillations of the high-rise building with the hysteretic damper and compare them with the across-wind oscillations.

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In this paper, the method of generating a turbulent boundary layer over rough wall, which has been proposed by authors, was verified by the turbulent characteristics to be put to practical use. Integral scales of turbulence and spectra of streamwise velocity fluctuations were investigated to be influenced by the size of computational domain and the length of the periodic zone. The influence of the length of the periodic zone could be seen in a higher part of the boundary layer. To check the influence of Reynolds number between the atmospheric boundary layer and the numerically simulated boundary layer, we modified the method to apply the model in the vicinity of the wall. We could not see the difference between the high and low Reynolds number simulation, except the mean velocity profile in the roughness layer.

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Shortening of R/C members caused by dry shrinkage for a base isolated building deforms a base-isolate-equipment. The deformation varies with its position. Usually, the largest value is at the edge of a building plan. The varied initial deformation leads to torsional vibration for the building. This paper examines this torsional vibration parametrically by 3-D dynamic analysis using the models of bilinear hysteresis systems for the vibration isolation materials. The results show that the initial deformation does not have an effect on the seismic ability of base isolated buildings for severe earthquakes. However, it leads to leave residual deformation after not only severe earthquakes but alsomoderate ones.

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We simulated strong ground motions during the 1993 Hokkaido-Nansei-Oki, Japan, earthquake (M_<JMA>7.8) based on its variable-slip rupture model and on its characterized asperity model to verify the characterizing procedure of source models for the strong motion prediction in future earthquakes. The asperity model was characterized by the total seismic moment, the short-period level of the source spectra, and the ratios of the area, the slip amount, and the effective stress on the asperity to those on the entire fault. The empirical Green's function method was applied to the actual calculation of the records at Sapporo JMA and Akita JMA.

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In this paper, a shaking table testing technique considering the dynamic Soil-Structure Interaction (SSI) is proposed based on the non-linear substructure method, by observation of the absolute acceleration of superstructure and a shaking table, respectively. Numerical simulation was performed to verify the proposed method. The numerical analysis model comprises the 2-layered cone model for a dynamic stiffness of soil and the bi-linear restoring force-relative displacement relation for a non-linearity of superstructure. The acceleration observation circuit diagram is derived from the differential equation of the total SSI system. Then, the simulation model including the transfer function of an actual shaking table with observation noise is applied to emulate its behavior during the test.

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A new spectrum analysis scheme and its application of modal identification are presented to identify accurate modal properties from ambient vibration measurements. In the scheme, the observable time sequences are modeled as ARMAMA model where the MA terms are added to an ordinary ARMA model. The modal properties are identified from the cross-and auto-power spectrum density estimates represented in ARMAMA models. In the paper, we derive the theory of the present procedure and demonstrate the modal properties estimation of a large coal silo from real ambient vibration records.

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Strain-controlled strategy is proposed here for tracing numerically the equilibrium path of elastic-plastic structure. For a designated element, its incremental strain consistent with the constitutive law can be directly given in this strategy. The core of this new strategy is the idea of amplifying the solution by the well-known load-controlled scheme and/or displacement-controlled scheme. When the strain-controlled strategy is used, the incremental perturbation method must be adopted to predict exactly yielding or unloading in all elements. The numerical examples of Shanley Model demonstrate that this strain-controlled strategy is effective.

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We study on the seismic performance of pile-supported 9-story RC buildings with different types of pile cap condition. We carry out earthquake responce analyses of the building supported by cast-in-place reinforced concrete piles and of the same building supported by steel pipe piles. Pile cap conditions of their pile foundations are assumed to be pin joints or rigid joints. The soil surrounding these foundations is supposed to have the same properties. The mass-spring models are used for their analyses. It is found that the maximum bending moment of piles with pin joints is smaller than that with rigid joints, and that, in case of the steel pipe piles, most part of the maximum bending moment is induced by the inertial force of the superstructure. Pile cap condition give less effects on the seismic performance of the superstructures. Furthermore, to compare the ultimate strength and the deformation capacity of the pile foundation with rigid joints to those of the pile foundation with pin joints, nonlinear static analyses are applied to the same building supported by the cast-in-place reinforced concrete piles. Frame models are used for the analyses. It is concluded that the foundation with pin joints has the larger deformation capacity and the smaller ultimate strength than that with rigid joints.

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Large-scale shaking table tests are conducted to investigate the effects of non-liquefied crust overlying liquefied soils on an embedded footing. It is shown that (1) The total earth pressure before liquefaction is induced mainly by the inertial force of the building, (2) The total earth pressure after liquefaction is induced mainly by the soil deformation, (3) The relation between the relative displacement and the total earth pressure is linear before liquefaction. It becomes nonlinear with the development of pore-water pressure, (4) The maximum value of the total earth pressure corresponds to that predicted by the Mononobe-Okabe method.

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In order to understand failure mechanisms of existing non-conformed reinforced concrete buildings during a severe earthquake, shaking table and static tests of a full-scale RC frame were conducted. A specimen of the RC frame was designed based on the building regulation that had used before 1971,under which an amount of shear reinforcements of columns was less than that under the current regulation. Several ideas to design a loading apparatus for the shaking table tests were taken into consideration to simulate the dynamic behaviors of the RC frame as a part of a whole structural system. The test results indicate that the existing non-conformed RC buildings have a high possibility of shear failure in columns.

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Through experiments to investigate effects of variables, such as quantity and pitch of confining reinforcement, material strength and thickness of hollow cylinders on strength and deformation characteristics of cylindrical confined concrete with hollow, equations to estimate the characteristics are derived. Main results obtained are as follows. (1) Experimental variables adopted in the tests expect thickness of hollow cylinder show similar influence on the characteristics to that in the case of cylindrical confined concrete. (2) About linear relations between effects of the thickness on the characteristics and ratios of the thickness to diameter of hollow cylinder are observed. (3) Equations for predicting strength and deformation characteristics are obtained through modifying the previous equations by authors for cylindrical confined concrete and the test results.

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The purpose of this paper is to establish a method for evaluating the full plastic strength of mono-pole steel towers instead of the normal yield strength. The bending tests on small models of partial towers are performed to prove the effectiveness of the nonlinear analysis by comparing with the previously obtained empirical results. The relation between the buckling strength and radius thickness ratio (D/t) are quantitatively evaluated together with the P-Δ effects. Also, this evaluation is ensured through the loading tests on a half-scale tower; the critical limit of D/t for maintaining the full plastic strength is found : D/t ≦ 33500/σ_y, and the allowable deformation of its top is 3% of the height.

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The effectiveness of improved connection details on the deformation capacity of composite beams has been investigated. Two types of improved connection details have been introduced to the composite beam specimens : a no weld access hole detail and a RBS(Reduced Beam Section) detail. Cyclic and quasi-static loading tests have been performed using full-scale specimens including the specimens with improved connection details and with conventional connection detail. The specimens with improved connection details have shown large deformation capacities than the specimens with the conventional connection detail. The no weld access hole detail has improved the moment capacity of the beam near the beam-to-column connection. Because of this effect, a wide area of the beam has yielded, so that the large deformation concentration and the flange fracture have not occurred. The RBS detail has also prevented the deformation concentration to the connection and the flange fracture by developing large plastic deformation area.

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Long service life, reuse and recycling are counted as three major measures for reducing environmental burden. However, the effects of these measures are not clearly defined, therefore, quantitative evaluation and investigation are required. This study conducts case studies on scenarios presumed for the environmental burden reduction for mid-rise steel building structure. Service life period of buildings, reuse rate of members and recycling rate of materials are considered as parameters. The study pays attention not only to the life cycle CO_2 (LCCO_2) but also to the amount of wastes. Additionally, in seismic areas, if the service life of buildings is extended, risks of large earthquakes increase. Therefore, the case studies assume the seismic design loads corresponding to the service life and calculate the steel weight. Major conclusions obtained in this study are as follows : 1)The environmental burden is reduced by raising the reuse rate of members and recycling rate of materials on stretching service life of the building within about 100 years. 2)Environmental burden does be not evaluated by single measure for evaluation, and it is necessary to carry out the synthetic judgment by multiple measure for evaluation.

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Though no SRC buildings had been collapsed by the previous earthquakes in Japan, 32 SRC buildings were collapsed by 1995 Hyogoken-Nanbu earthquake. Those buildings had SRC columns in which open-web type steels were encased. Authors conducted loading tests of the columns in a damaged 6-story SRC building in Kobe and also conducted tests series of SRC columns to investigate the cause of the collapse and examined the strength and ductility of the SRC columns. Findings are the followings. ○!1Failure modes are critically influenced by the axial force caused by the overturning moment during earthquake. ○!2The loss of the steel section by the rivet hole does not affect the load deflection much. ○!3The ultimate strength of the SRC columns with not only full web steel but also with open web steel can well be estimated by the plastic theory using truss-arch mechanism

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Lateral wall pressures as well as wall strains due to stored coal during filling and discharge were measured at a 70,000 ton capacity coal silo, and overpressure factor was studied using the measured data. The silo has four linear wedge-shaped hoppers with respective moving RDM's (rotary discharge machines). Overpressure peak values and variations during discharge were found to be larger than the ones during filling. Furthermore, the distance from the RDM's showed large influence on the overpressure phenomena, and a design recommendation for the overpressure factor with due regard to the distance is proposed and compared with the measured data.

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To examine properties and load-carrying capacity of composites slabs of steel plates with steel studs and concrete with top reinforcements in ISO fire, fire tests and analyses of heat transfer and elasto-plastic stress-deformation were carried out. And a simple calculation method to evaluate load-carrying capacity of composites slabs was proposed. This calculation method based on simple plastic theory on the viewpoint of considering in strength degradation zone of concrete by heat transfer during fire. After this study, the following conclusion could be obtained. 1) The composites slabs designed within the limit of ordinary live load have flexural failure mode in fire and the load-carrying capacity of composite slabs can be calculated by using the formula proposed. 2) Composite slabs with steel studs having shear stress more than 0.5N/mm^2 collapse by shear stress on the initial stage of ISO fire. This shear failure is caused by decreasing of shear strength of concrete due to giving rise to tensile stress in concrete. Tensile stress in concrete increase on the initial stage of fire, because of the restraint of elongation of steel plates through steel studs. 3) However, generally, composite slabs have axial restraint more than 30% of full axial restraint in structure, the decreasing of shear strength of concrete doesn't occurred during fire, so shear failure can be avoided.

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This paper describes an experimental study on the fire performance of half SC slabs. The half SC slab is a composite slab consisting of steel plate instead of bottom rebars of reinforced concrete slab. Steel plates were welded with steel studs and T-shape steel. The objective of this study is to experimentally evaluate the effects of the dimensions of T-shape steel according to load. The following findings were obtained by the experiments : 1) T-shape steel in concrete prevents the half SC slabs from the shear failure during the initial phase of heating because T-shape steel binds thermal expansion of steel plate and the tensile stress of concrete are smaller than the concrete without T-shape steel. 2) Fire resistance of the half SC slabs is improved by T-shape steel avoiding the shear failure.

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