The mortar using magnesium phosphate cement (MFC) exhibits various fresh properties and physical properties after hardened depending on the cement composition, fine aggregate/cement ratio, and dosage of a set-adjusting agent. The author conducted several mortar tests to check the nature. Test results reveal the following characteristics that MPC mortar exhibits: 1) compressive strength development of 15N/mm^2 or more after one hour curing at a 20℃ environment, 2) excellent strength development at low temperature, 3) almost eaual properties in volume change and thermal coefficient of expansion to that of ordinary portland cement concrete. 4) low drying shrinkage, 5) excellent adhesive strength to substrate irrespective of the type of concrete and treatment methods, 6) superior chemical resistance, and 7) no corrosiveness to reinforcement because phosphate that is a component of MPC, is a corrosion inhibitor.

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This report is the comparison of cracking of concrete slab in-place, which was cast on the some subgrade; Compacted sand fill, styrene form, polyethylene sheet, excelsior board and steel sheet, by using normal concrete, conecrete containing cutter polishing residue and artificial lightweight concrete. The concrete slabs were cast under the hot and sunny day in summer. When concrete was cast on the pervious base (sand). the shrinkage cracking did not occurred at any concrete, On impervious base an excessive amounts of cracking occurred. The shrinkage cracking amounts depend on the degree of pervious ness, but the shrinkage cracking at artificial lightweight concrete did not occurred in dispersion Weather the shrinkage cracking occur at concentrate or dispersion, it seems the degree of water content of aggregate or containing materials and subgrade.

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Our company develops building automation construction system that constructs the building by the utilization of the automation machine, and it has been applied to the construction. This system aimed at shortening in construction period and labor saving, improvement of quality and the safety, reduction in the workload, etc. Through the application to three constructions, the following were carried out: Investigation of improvement process of the system and the evaluation. As the result, the following were proven: That it realized the shortening in cycle construction period of the construction system by the parallelization of the work and that it realized construction period shortening and man-hour reduction of production system assembly, disassembly by simplification and light weight of the system.

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Aggressive environment and in-service loading can cause the resistance deterioration of existing reinforced concrete structures. It is necessary to formulate time-deppendent reliability analysis on account of developing the rational maintenance strategy and reliable prediction of service life of deteriorating structures. In this study, the reliability function of deteriorating reinforced concrete structures due to aging under load combination consisting of dead, live and main external loads of earthquake is analytically investigated, applying the advanced first order and second moment method with the statistics of the residual resistance of each element of systems which has survived up to timer. The results by proposed method show comparatively good agreement In comparison with those by Monte Carlo simulation.

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This paper discussed Damage Index Function by which damage state of individual building can be estimated. and proposed the method for deducing the functions with structural parameter of the load-carrying capacity fbr buildings. We can apply the 3D nomograms of the obtained functions with three different types of parameters to utilize for various kinds of seismic risk management; for example, damage evaluation of individual building for an assumed earthquake, estimation of the standardized strength of buildings in regions not for generating damages. and stochastic estimation of return period on regional input motions that give rise to devastating damages to buildings.

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Site amplification characteristics are indispensable for evaluating strong ground motions at soecific sites. Theoretical methods, such as 1-D wave propagation analysis, are often employed for this purpose. However, prereauisite structures are not necessarily obtained with ease. In the previous paper, we applied seven site classes in terms of average shear-wave velocity of ground from surface to 30m depth (V30) to site classification sheme. Site amplification factors, Fa for short periods and Fv for longer periods, for seven site classes were derived from strong ground motion records and nonlinear response analysis. In this paper, We proposed a practical method to evaluate response spectra on bedrock using site amplification factors, Fa and FV. The results showed that bedrock motions evaluated by the proposed method aereed with the results using theoretical 1-D analysis.

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Seismic pounding of two closely-spaced buildings can be a serious hazard, and adequate building separation distance must be used to preclude pounding. It can be calculated as the peak value of the relative displacement between the buildings through time history analysis. For an alternative and more practical estimate, the writers proposed the "spectral difference (SPD) rule" that simply uses the buildings' oeak displacements. The present paper proposes a simplified method combining the rule with elastic response spectrum to approximate peak inelastic displacement of each building. Utilizing this SPD-based method, the paper clarifies the relative displacement trends based on building periods, damping ratios, ductility demands, and earthquake soectral characteristics. The method is validated and various trends discussed by using numerous code-comoatible building pairs and 33 earthquakes. The SPD-based method is shown to be much more accurate than other simplified methods, due to its ability to account for the inelastic vibration phase of two buildings. The results are also readily applicable to the problem of finding a necessary sliding seat distance to prevent falling of a bridge, which is supported by two separate structures developing relative motion.

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This paper presents the closed form solutions of minimum weight design problem of shear building structures, some of whose story stiffnesses are preselected for specified fundamental frequency. The easier methods to derive the solution for specified srade design problem of shear building structure are also presented, by using the solutions of the above problem. These methods consist of some design procedures by using the method deriving from one solution to another successively. A design example of five-story shear building is introduced to demonstrate the usefulness of these methods.

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We present a robust nondestructive approach for detecting flaws in a frame structure from its measured response. Due to testing limitations, the number of measurements is often less than that of potentially damaged locations. Direct application of conventional least-squares approaches yields an ill-posed inverse problem. To overcome the difficulty, we formulate damage detection as a mixed combinatorial-nonlinear least-squares problem, in which the subset of unknown parameters is sought. along with their values, that best represents the location and extent of the damaged sites. The present formulation is suited for finding a limited number of damage sites. To obtain more stable estimates, further, we propose a grouping strategy, wherein the damage parameters giving similar effects on measured response are grouped using the sensitivity of the response with respect to the damage parameters. Through two numerical examples, we demonstrate the proposed method and examine its oerformance.

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In general, hysteresis models that are applied to a numerical analysis part of substructure on-line tests do not refer to an experimental behavior of members/subassemblage under loading tests on real-time basis. The objective of this study is to develop a new experimental technique for substructure on-line tests based on nonlinear hysteresis characteristics estimated with a neural network. New learning algorithms for the network applicable to substructure on line tests afe proposed focusing on input layer components and a normalization method for input data, and their validity is examined through several numerical analyses. The results show that the new algorithms proposed herein successfully reoroduce the dynamic behavior of model structures.

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In considering local buckling of H shaped member for the designed structures, analytical models have much more freedom degree number and are very costly. Therefore, in this paper, we will suggest a consistent and convenient analytical method for H shaped steel member involving local buckling behavior. In this method, multi-surfaces for yielding and buckling behavior are considered in the space of (M_i,M_j,N ). Each surface corresoonds to the yielding and buckling strength of each buckling flange in H-section member. And the effect of local buckling behavior evaluates as the softening behavior for only a couole of surfaces corresponding to the buckling flange Finally we will examine the validity and usefulness of our method through some numerical examples.

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Until recently few research efforts have been directed toward the application of seismic isolation systems in large-span spatial structures. This is due to the light weight and relatively long natural period of this type of structure which makes it difficult to apply the commonly used isolation system composed of laminated rubber isolators and dampers. In this paper, the use of a seismic isolation system with sliding mechanism is proposed for large-span spatial structures. In order to confirm its effectiveness in reducing the seismic response, shaking table tests are performed using a small-scale arch model supported by the base structures. It is confirmed that the proposed seismic isolation system is effective in reducing substantially the response due to horizontal ground motions. It is also demonstrated that the response of the arch is significantly influenced by the dynamic properties of the base structures, but can be well predicted by the dynamic response analysis considering the arch-base structure interaction.

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The objective of this paper is to evaluate the seismic performance of wooden structures. First, shaking table tests and static tests of wooden unit frames installing various seismic elements have been carried out. Mud-plastered walls and penetrating tie beams were included in the soecimens by considering Japanese traditional structure. From the results of these tests, the dynamic characteristics of wooden frames in terms of damage processes, hysteretic characteristics and hysteretic energy dissipation are clarified. From the comparison of dynamic tests and static tests, it is found that the skeleton curves of two tests are almost similar. It is emphasized that wooden frames with mud-plastered wall have the large deformability.

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This paper is to report our experimental results on static horizontal resistance for Japanese traditional mud walls subjected to static lateral force. As the first step of this study, the wall width is limited to be IP (equals to 91cm). For a mud wall frame, the resistance force is assumed to be caused by the following four factors: 1) Compressive vertical pressure force between soil wall and beam/sill at all corners, 2) Compressive vertical pressure force between soil wall and embedded horizontal wooden batten 'Nuki', 3) Equivalent friction force between wall and beam-column frame, and 4) Moment resistance force at the joint of beam and column. The static collapse experiments have been carried out to verify the validity of the assurrmtion mentioned above, where many experimental patterns have been studied with or without the factors. By the investigation on the resistance force of mud walls due to each experimental pattern, the partial degree of each factor can be clearly understood. Such results clearly indicate the degree of the lateral force capacity due to each factor for mud shear walls.

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In this study, the characteristics of wind forces on a traditional five-story pagoda and the response of the pagoda induced by wind are investigated using wind tunnel tests and wind response analyses. The wind tunnel tests are carried out using pagodas with various configurations to determine the effect of these configurations under wind forces. The results obtained from the study are as follows. 1. Comparing along wind forces on a pagoda and on a prism with an aspect ratio of 4, the mean and fluctuating wind force coefficients on the pagoda are lager than those on the prism at most angles of attack. The component of vortex shedding from the pagoda accounts for small to all fluctuating power. 2. The structural dynamic characteristics of the pagoda are determined by making a series of review of literatures. The wind response of the pagoda with !"sohrin" and "shinbashira" (center pillar) is l.4〜1.8 times that of a pagoda without them.

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This paper reports the results of quasi-static cyclic loading tests conducted for modeling the two-dimensional contact response between a foundation stone and a circular column base of traditional timber frames. Constant axial loads and cyclic forced rotations are applied to three column-base specimens placed on a stone foundation. Three sets of axial load conditions are considered for each specimen. The three specimens are subjected to step-wisely increasing, constant, and step-wisely decreasing amplitudes of cyclic rotations, respectively. In order to obtain the moment-rotation angle relationship at the column base, we estimate the position of the center of mass for the distributed reaction force in the axial direction. We observed from the tests that the magnitudes of the axial load and the differences among the cvclic loading programs have little effect on the relation between the rotation angle and the location of the center of mass, for which an empirical formula is provided.

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The objective of this study is to investigate the elasto-plastic behavior of RC seismic shear wall subjected to horizontal two-directional loading. Static loading tests of box type and cylindrical shear wall were performed adopting various loading patterns on X-Y plane. According to the test results, the maximum shear force and skeleton curve of shear force - deformation angle relation are not so much affected by orthogonal damage and loading path. The concept of resultant shear force - total deformation angle was presented as one of the options to look into the property under horizontal two-directional loading.

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Mullion-type walls, which are separated from columns and are treated as nonstructural elements in general. jointed to RC frame as bending members may raise horizontal load-carrying capacity. However there is probability that the Mullion-type wall's axial elongation has a bad influence on behavior of RC frame. In this paper, one eighth scale two story and three storv specimens were made and tested. Those consist of I span RC frame and the Mullion-type walls at every story. The conclusions are as follows. The Mullion-tvpe wall elongates axiallv in each story, and the upper beams 3re forcibly and more conspicuously deformed by the accumulation of the walls' elongation. Consequently the rotation angle of the upper beams is about one and a half times as large as the drift angle. Experimental horizontal load-carrying capacity correspond to value caluculated as the elongation produces plastic hinge in beams. These verification indicates that the Mullion-tvpe wall joined to RC frame raises horizontal load-carrvmg capacity unless the elogation causes brittle failure of beams.

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In this paper an analytical model for RC columns considering the nonlinear behavior in both shear and flexure at the cyclic load is proposed. The main feature of this model is that the nonlinear shear distortion is added to flexure model in a series, as an uncoupled force-deformation relation, on the basis of a flexibility formulation. The monotonic shear force-distortion relation is initially calculated by Modified Compression Field Theory (MCFT). In order to improve the shear force-distortion relation derived by MCFT, a modification procedure based on experimental data is also proposed. A hysteretic model including pinching and strength degradation is employed for shear cyclic behavior. Using this model incorporated with fiber technique, an elastoplastic analysis of RC columns retrofitted by pre-tensioned high strength steel bars fbr earthquake resistance is performed. In fiber modeling, a spread curvature distribution is investigated in several cross sections along the member axis. The resultant flexural force must satisfy the unique bending moment diagram given by external force. A correlation study based on the analytical simulation of experimental tests which were carried out during past few years shows an excellent agreement and a perfect validity of proposed nonlinear analytical model.

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This paper presents a seismic response prediction method for steel frames with hysteretic dampers. This method is based on energy balance and is able to predict the seismic response of frames with dampers yielding under an earthquake to occur several times during the life of buildings. In this method, the number (_dn_l) of eauivalent cycles of plastic deformation in hysteretic dampers is utilized to predict earthquake response of frames with hysteretic dampers. In order to grasp the _dn_l values, earthquake response analysis of analytical frames with hysteretic dampers is carried out. And, the adequacy of seismic response prediction by this method is verified through a comoarison with results of earthquake response analysis of three different story frames.

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Cold-formed thin-walled steel members with a thickness of around 1 mm have been used as structural members for residential houses since 1990s in Japan. The application of the members to the houses requiring fire resistance has been limited, however, due mainly to a lack of information on mechanical properties and buckling behavior of such a thin steel member under elevated temperatures. In this research, therefore, material tensile tests and compression column tests were conducted to clarify the characteristics and to examine if existing column design formulae for normal temperature can be applicable. The tests covered a thickness from 0.5mm to 1.6mm and a temperature up to 600℃. It was reported in this paper that much difference is not observed on yield strength and young's modulus degradations up to 400℃ from traditional thicker building members, and existing column design formulae for normal temperature may be applied to estimate the column strength of thinwalled steel members under high temperatures.

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Local buckling behaviors of thin-walled stainless steel stub-columns were experimentally investigated. Six types of sections, i.e., angle, channel, lipped channel, H-shaped, square box, and circular cylindrical sections were tested. These specimens were formed from ferritic, chromium stainless steel sheet designated as SUS410L, whose specified yield strength for design is planned to be 235N/mm^2. Effective width-to-thickness ratios of unstiffened and stiffened plate elements were established from angle and box sections, respectively. The effective widths of individual plate elements in channel, lipped channel, and H-shaped sections in which different edge conditions are involved can be calculated on the assumption of pin-connection between adjacent plates. The limit diameter-to-thickness ratio was established from the test data of circular cylinders.

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The discusser wants the authers to explain the following items: 1. Te definitions of some technical terms uniquely used in the paper, 2. Input data used in the thermal stress analyses.

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The authors thank Dr.Masatoshi Yamazaki for his discussion, and these indication items are appropriate.The answers are as follows: 1.The term "internal restraint thermal crack index" means thermal crack index in exterior surface; the term "external restraint thermal crack index" means thermal crack index in the central. 2.Commercial analysis program is used. Input data follows general values suggested by Standard Specifications for Concrete Structures. 3.This analysis is intended to investigate the frost damage at early age. Therefore the analysis period is set up till the 28th day.

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