The melting snow system is required in heavy snow area. The heating system by the quasi microwave is proposed and developed in this paper. The return loss of steel manufacture slag was measured by the S parameter method in which waveguide and network analyzer were used. Steel manufacture slag was heated by the quasi microwave inside the improved waveguide. The temperature of surface was measured with thermocouple inside waveguide. The relation between heating characteristics and the return loss was examined in the case of steel manufacture slag, cement mortar mixed with steel manufacture slag. The heating system was constructed with mortar block, leakage waveguide and electromagnetic generator. The shield effect against unnecessary electromagnetic wave was measured with the horn antenna and spectrum analyzer. The temperature of surface was measured with infrared thermography. Temperature of 40 degrees increased for 300 minutes in the microwave chamber.

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This study aims at establishing a theory of compressive strength which is useful for the mix proportion to get required compressive strength in porous concretes. Making porous concrete model specimens using ideal spherical aggregates such as alumina ball and glass bead, an experimental investigation was conducted regarding the influence of total void ratios, spherical diameters of the aggregate and water-cement ratios on compressive strength of the specimens. Moreover, a consideration was done concerning a compatibility of the experimental results and the theory by means of a truss model considering the bridge effect of the aggregate.

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This paper shows a specific example of the quality index along a concept of quality index on the surface layer of concrete ground work, proposed in previous paper. At first, we limited our object to the flatness and the surface strength of ground work made by normal weight concrete. Then, we made some samples of ground work under a few execution conditions by using several slumps of concrete, and measured their flatness or surface strength by the straightedge method or the scratching method. Finally, we showed relations between the flatness or the surface strength, the slump and the execution condition, as a specific example of the quality index.

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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 bricks imaged finishing and the evaluation value of aging 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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We present three-dimensional results of flow around two circular cylinders in staggered arrangement, which are located in a uniform flow. The two circular cylinders in numerical computations are arranged in the various distances to both in-line and transverse directions between the centers of two cylinders. It is well known from experimental data that the fluid forces acting on the circular cylinders vary depending on the spacing between the cylinders. The computed results at the Reynolds number of 1000 are discussed and are consistent with the experimental results in terms of the aerodynamic characteristics of circular cylinders.

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We examine behaviors of close-fault strong motions calculated by the extended stochastic simulation method. Horizontal and vertical peak ground velocities (PGV) calculated by this method behave quite differently from PGV calculated by the attenuation relationships. With decreasing the source distance, horizontal PGV grows monotonically and vertical PGV rapidly decreases, while PGV for both components calculated by the attenuation relationships saturates in close-fault zones. Comparison between the near-field term, the intermediate term, the far-field term in the elastic-wave Green's function and the sum of the three shows that these differences are generated because of a neglect of the near-field term and the intermediate term in the stochastic simulation method. This comparison also suggests the frequency range dealt with by the extended stochastic method should be confined to higher frequencies for shallower earthquakes. More specifically, the frequency range may be above 2-3 Hz for shallow (a few km from ground surface) earthquakes. This is confirmed to be adequate from the comparison close-fault earthquake motions in the Hyogoken-Nanbu Earthquake and earthquake motions simulated by this method.

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In the 1995 Hyogoken-Nanbu earthquake, buildings were severely damaged by immense earthquake input energy, which was brought within only a few seconds by distinctive velocity pulses, called killer-pulses. So we made various earthquake response analyses focusing on the distinctive seismic pulses included in near-field earthquake ground motions. From analysis results, we considered the relationship of a period and an acceleration amplitude of the seismic pulse with building response, such as story shear distribution, ductility factor and so on, and explained how the seismic pulse influenced on mid-story collapse. We also showed the effect of seismic damper for near-field earthquake was less than that for far-field earthquake through the example of optimum calculation for seismic damper quantity.

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Acceleraion source spectra of intra-slab earthquakes in the Philippine Sea plate were evaluated by eliminating the path and site effects from observation records. High-frequency levels M_<HF> were evaluated from the acceleration source spectra, and stress parameters Δσ were calculated from M_<HF> and seismic moment M_O. The relationships between Δσ and M_O and Δσ and focal depth were examined and compared with those of the Pacific plate. Upper level of Δσ is not affected by M_O and is 40-80MPa. But lower level of Δσ is affected by M_O, that is, lower than 5MPa for small earthquakes (Mw<5.7), 20-80MPa for medium earthquakes (5.7<Mw<6.6), and 60-80MPa for large earthquakes (Mw>6.6). And, lower levek of Δσ are different to each other for large earthquakes of two plates. Δσ is constant to focal depth for medium and large earthquakes.

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To examine the relation between seismic intensity(JMA) and hospitals' damages, composed of interruption of medical functions, daily life functions, equipment as well as building damages including nonstructural elements, questionnaire surveys were conducted for the 2003 Off Miyagi Prefecture Earthquake, the 2003 Northern Miyagi Prefecture Earthquake and the 2003 Tokachi-oki Earthquake. Hospitals near the earthquake observation stations were selected for the surveys. Meanwhile, to compare damages of hospitals with those in other common facilities, many public facilities, such as ward offices and schools, were also investigated. Results are concluded as follows. a) Damage ratios of many building damages of hospitals are higher than common facilities, and increase with older hospitals built before 1980. b) Many building damages begin to take place at a seismic intensity 5+, and increase rapidly over seismic intensity 6. c) Damages of many equipment items related to daily life functions begin to take place at a seismic intensity 6. d) Many medical instruments show no physical damages till seismic intensity 5+, but some may be unable to perform normally as early as at a seismic intensity 4 due to interruption of daily life functions. e) Interruption of most medical functions starts at a seismic intensity 6.

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An envelope model of acceleration ground motions (> 1Hz) is proposed to synthesize Green's functions on the seismic bedrock. Source, path, and site effects of the envelope are inverted using group delay time of acceleration records. The envelope shape for source is modeled by Boore's model. The envelope shape for path is modeled based on the multiple forward scattering theory. The envelope model for path is controlled by physical parameters of the random media characterized by autocorrelation function of fractional velocity fluctuation. The characteristic time of the envelope model for path is proportional to power of hypocentral distance and independent to frequency.

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Discussed in this paper is the lateral stiffness and buckling load of laminated rubber bearings with a hollow circular section. The highly stable behavior of the hollow circular rubber bearing, when a relatively large vertical load is acting on it, is experimentally observed and analytically verified. It is possible that the allowable lateral displacement of the device will exceed the limit length that is commonly believed to be less than the diameter of the device section. The thickness of the steel plates plays a more important role on the stability than is expected in case of conventional rubber bearings.

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This paper presents a practical optimum design method for base isolated buildings. In this study, first, we propose a simple cost function for a base-isolation story. Then, we present a two-stage optimization problem by dividing a base isolated building into two substructures, the base-isolation story and its upper and lower structures. This allows us to get a closed-form solution to the sub-optimization problem of base-isolation story. The use of the closed form solution makes the proposed method efficient. Design examples demonstrate the validity of the present method.

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A method is proposed for selecting optimum discrete sections of steel frames using a two-step relaxation method. At the first step, the discrete optimization problem is approximately solved by using a continuous optimization problem wherein approximate expressions are applied to the standard sections. At the second step, the near optimal set of discrete sections is selected using the solution of the relaxation problem whose design space is limited to the neighborhood of the optimal solution obtained in the first step. Through the numerical example of a 6-story 5-bay plane frame under elastic constraints, it is demonstrated that a discrete solution can be obtained whose rate of increase in total steel volume from the continuous optimum design is only 1.8%. This approach is general enoueh to be applied to the problems under elastic-plastic constraints and those with any type of standard section lists.

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Floor incline, differential settlement and cracking of foundation in existing detached houses were investigated. The inspection was carried out, prior to neighboring constructions, to confirm the service life of basement. A total 864 houses in 113 areas on the soft ground in Tokyo metropolitan area was covered. The major findings are as follows. 1. Extent of differential settlement was generally improved in houses built with the current specification of the housing loan corporation but a 10 percent cases on the soft ground area exceeded the permissible limit of 25 mm. This implies that the differential settlement cannot be eliminated solely by a basement construction specification. 2. Extent of floor incline depends on the measured section and showed 20 percent larger value than the measurements at each end of the floor. This maximum angle of gradient was controlled by the differential settlement rather than the foundation construction specification and may become less than 6/1000 when the differential settlement less than 25 mm. 3. Extent of column incline was approx. 2/1000 even without any floor incline. A floor incline less than 4/1000 may be necessary to give a column incline less than 6/1000. 4. No significant relation was found between basement cracking and differential settlement or angle of gradient. A foundation crack width exceeding the control value of 0.5 mm was found in a 20 percent of houses built with the revised specification.

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Two series of shaking table tests, i.e., one had a quay wall and the other had not, are conducted to clarify a lateral ground force acting on piles in liquefied and laterally spreading soils. It is shown that (1) The lateral ground force acting on a pile in laterally spreading soil as well as that in liquefied soil has character of solid ground due to decrease of excess power water pressure and recovery of effective normal stress after liquefaction; (2) The lateral ground force acting on a pile near quay wall becomes nine times larger than the maximum inertial force at a pile head in laterally spreading soil.

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Soft computing technics have often been used in various engineering fields. A neural network, one of them, has also been noticed as one of powerful approaches that can solve complicated problems. The present research deals with that how to utilize accumulated results being yielded from structural numerical simulations or experimental tests. The neural network has a potentiality to store them without a huge space in the knowledge base systern. The neural network can also interpolate the descrete results with respect to given data, linearly or non-linearly. Furthermore, the availablity for a reasoning engine in the expert system is also investigated. The system would be so available for all designers, when the method to extract easily the digitized certain knowledges was established. As the example, the elastic-plastic buckling behaviors of single layered reticular domes whose behaviors have to be estimated with many structural parameters, are treated. Through several case studies, the performances of the neural network are discussed.

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The purpose of this study is to develop the vibration control system of plural modes of large span structures using spatially dispersed arranged TMDs(tuned mass dampers). In this study, in order to determine the design parameters of TMDs, MTMD(Multiple TMD) method is applied. And to determine the arrangements of MTMD, the method using the superposed shape of controlling modes is newly proposed. The following results of the proposed method compared with the method using the usual single TMD of equal mass were found thorough numerical experiments. 1) The proposed method is especially effective for controlling structures overall and the effect is closely connected with the bandwidth of MTMD. 2) The difference between responses using the equivalent mass and the mass of whole structure for setting up design parameters of MTMD is small and the newly proposed average equivalent mass is useful.

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In this paper, the distribution of maximum displacement responses of traditional timber houses is calculated in consideration of both floor stiffness and non-structural walls. The results may be summarized as follows: the floor stiffness is not a significant parameter of the maximum displacement response. The approximate excressions are presented in relation to the ultimate horizontal resistant force and the amount length of structural wall. The maximum displacement response in consideration of both floor stiffness and non-structural walls is approximately estimated as 1.15 times of the maximum displacement response calculated by the lumped mass system model.

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This monograph relates tension of a column bases in adjustment between an experimental result and calculation by the standard or general design for conventional wooden structure. At first, 2-stories and 126 m^2 model house was given static load to examine the experimental measure and then 2 stories and 27 m^2 square houses was loaded in the same condition to investigate an effect of perpendicular walls to the load direction. Furthermore, some partial models of columns and sills were experimented to clarify the effect of rocking of column and confining of joint. After the experiments, the experimental measurement was revised with the effect of the rocking and confining, and compared with the standard calculation. As a conclusion, when the story deformation angle is 1/50rad. the rocking considerably affects the tension of column bases. The tension is not serious on every column base in the elastic limit. The required value of tension of corner columns seems to be unreasonable, but there is a noteworthy case that the tension more than the required value occurs to the column bases with compressive braces. The perpendicular walls shared with the corner columns seem to carry 1/3 to 1/2 of stress if it has the same specification as the walls in the same direction as the load.

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This paper discusses the effect of various parameters on bond strength of deformed bar in lap splice and pullout specimens using two-dimensional finite element method. The parameters were transverse reinforcement, concrete strength and the arrangement of main bars. The parameters of analytical models were similar to those of experimental specimens. The results show that: (1) The angle between the compressive force from bar to concrete and the bar axis is constant irrespective of transverse reinforcement ratio or concrete strength; and (2) The transverse reinforcement makes the compressive stress between the main bars comparable to compressive strength of concrete.

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This paper proposes the new measuring method for a normal compressive stress distribution in concrete members by using a symmetry of geometry and loading pattern. This method would have the ability to develop effectively a constitutive model for concrete in an inelastic-finite element analysis, based on a compressive stress distribution measured in concrete members. Besides to observe precisely ever-unknown compressive stress distribution in concrete members. For a verification of that method, a study was conducted with experiment and analysis. In the experimental part of the study, tests were conducted adopting it to concrete cylinders subjected to uniaxial compression, and an inevitable probrem in measuring is verified, based on the results of failure, average compressive stress-strain curve and poisson's strain. In the analytical part, the inevitable probrem is verified, based on the results of an inelastic-finite element analysis. The results indicate the validity of the measuring method.

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Shear behavior of a new composite shear wall system is investigated through a series of cyclic loading tests on a total of four specimens. One specimen was designed such that shear failure would occur in the CFT columns connecting RC wall panels to the grade beam. The failure caused large axial shortening of the specimen. Small section wide flanges were used as the rims of the RC wall panels of two specimens were small. Failure was mainly instigated after these wide flanges yielded, because of large deformation of the wide flanges that led crashing of RC panel. Hysteresis of these three specimens was relatively stable, unlike those observed fbr RC shear walls in general. FEM was employed to simulate elastic-plastic behavior of the specimens. Design methods to prevent shear failure of CFT and RC panels are suggested using the analytical and test results.

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An emergency seismic retrofit technique is indispensable for the rehabilitation of damaged RC buildings immediately after earthquake attack. There-fore, it is important to develop quick and convenient emergency retrofit technique to recover the seismic performance of the structures damaged by earthquakes. It is well known fact that the strength and ductility of RC columns can be extremely enhanced by transverse confinement which also acts as shear reinforcement. Considering this fact an emergency retrofit technique utilizing pre-tensioned high strength steel bars (PC bars) and steel plates is proposed in this paper. The effectiveness of the proposed retrofit technique is experimentally investigated and analytically evaluated simultaneously.

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This paper presents results of welding inspection and loading tests conducted to beam-to-column connections cut out from two existing steel buildings constructed in the early 1980s. From the results of thorough welding inspections, i.e. macro-structure tests and ultrasonic inspection, characteristics of welding defects are investigated regarding the location of defects in the deposited metals, kind of defects, and the rate of occurrence. From the results of dynamic loading tests conducted on the beam-to-column connections, the influence of defects on the deformation capacity and the failure procedure are observed.

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The authors reported on the experimental study of a newly developed buckling-restrained braces using steel mortar planks in the previous paper. In this paper, the authors further improve its detail and simplify fabrication. Specimens that are changed stiffness of the restraining part and width-thickness ratio of the core plate manufactured. Static, loading testing was conducted by applying increasing loads alternately in positive and negative direction. The cumulative ductility factor, the energy absorptionrate, and the final characteristics of the buckling-restrained braces are analyzed. As results, the performance evaluation of the buckling-restrained braces is quantitatively showed by an equation.

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A thick steel shear panel fabricated without welding is examined in order to investigate its feasibility as a passive control device. Numerous small size specimens of three different steel materials are examined both experimentally and analytically. Under monotonic loading test, the specimens exhibited extremely large deformation capacity as well as large maximum strength, far beyond those of ordinary shear panels. Under cyclic loading, they also demonstrated significant fatigue life as much as 250 times those of ordinary thin panels. The same material is tested under axial monotonic and cyclic loads in order to compare with the shear loading case. It is found that the monotonic and cyclic stress-strain relationship and even the fatigue life are closely correlated between the two different loading cases. Based on such a correlation, a method of conversion from one loading case to the other is proposed.

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Cumulative deformation capacity is one of the most important benchmark for the performances of elasto-plastic dampers within vibration-controlled buildings built in seismic area, because this value is considered to be related deeply to the cumulative energy dissipation capacity and validity life of the dampers. However, estimating this value under random vibration is not easy because they are affected by loading histories. In this paper, relationship between cumulative deformation capacities and loading histories of buckling restrained braces, which are representative elasto-plastic damp ers, are analyzed through datas of the past various experiments, and simple prediction methods are proposed.

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We present a framework for stability design of plane steel frames using the linearized buckling analysis. The previous approaches using the linearized buckling analysis often underestimates significantly the allowable stress for compressive members. To overcome the difficulty, we employ higher buckling modes and select the members playing crucial roles in the buckling modes. Such members are selected using the sensitivity coefficient of the buckling loads with respect to the flexural stiffness of each member. The reduction of the allowable stress due to coupling of stability and inelasticity is considered only for the selected members. Furthermore, we introduce the concept of design allowable Ioad factor for systematic implementation of the proposed method. The present approach does not need the distinction between braced and unbraced frames. We demonstrate the feasibility of the present method by applying it to an irregular unbraced frame having a slender column.

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This paper presents an analysis method of steel frame with bolted beam-to-column connections using buckling restrained knee brace dampers. In order to obtain earthquake response of this system correctly, a detailed analysis model based on past research must be used. This paper proposes a simplified analysis model by decreasing the number of freedom of the detailed analysis model for the purpose of reducing the amount of time for analysis. The validity of the proposed analysis model is verified by comparing with earthquake response analysis results of the detailed analysis model.

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Analytical investigations are conducted on the tensile elasto-plastic behavior of local connections in concrete filled square steel tube (CFT) column to steel beam connection using external diaphragm. This paper proposes a new analytical model for predicting the load-displacement relation of such local connections. This model is developed by superposing the load-deformation relations of a tube flange and web. The tube flange is modeled as a grid beam with a tetra-linear load-deformation relation, while the tube web is modeled as tensile members with a tri-linear. The strength of external diaphragm is superposed to strength of these tube load-deformation models. The analytical results agree approximately with the experimental results up to a large deformation.

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Theoretical studies are presented on the prediction of strength of a composite beam-column subjected to non-symmetric bending. The case of bi-directional bending, where directions of the end moment vectors at the both ends are not paralle, is also investigated. Sophiscated ultimate strength theory is introduced, where the deflection curve is assumued as a part of cosine wave and the critical state is estimatede as the arrival of the most outer fiber strain at the limit strain of the plain concrete. Proposed method shows a good agreement with precise numerical solutions and experimental results.

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The discusser wants to point out the following item 1) and to ask again the item 2), because the reply of the authors willfully put a false construction on discusser's question and include confusion and disorder between scientific terms and administration terms. 1) "Allowable stress of the ground" used by authors does not exist actually and is not acknowledged as a scientific term. 2) Why the authors use the word of "allowable stress of the ground" which is not a scientific term and inappropriate to appear in a paper of journal as a main keyword.

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The investigation was performed to indicate the usage of the technical terms of the allowable bearing capacity, the allowable bearing power and the allowable stress in analysis of the foundation on the ground. The allowable stress named globally for a material is classified locally according to the stress conditions of compression, tension, shear and bending. The allowable stress means the allowable bearing capacity for the ground. The allowable stress is obtained by use of the ultimate bearing capacity in taking account of the safety factor.

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