Mixture proportion of high strength concrete is controled as normal distribution inspite of compressive strength level. This could be following the example of quality control of popular readymixed concrete. There are many unclear point, testing methods and technical factors, that effect on shape of probability distribution of compressive strength in high strength concrete. And additionally, there are scarcely statistical reports of probability distribution of compressive strength in high strength concrete. It was estimated that effects of specimens on probability distribution of compressive strength and propose to mix design of high strength concrete.

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Volatile organic compounds (VOC) emitted from two types of water based emulsion paints were measured in this study. One is a water based emulsion paint whose quality meets to JIS K 5663:2003 "Synthetic resin emulsion paint and sealer" and the other is a water based emulsion paint whose quality meets to both JIS K 5663:2003 and the W1-grade requirement which has been proposed by Japan Paint Manufacturers Association as the highest grade in VOC reduction for water based emulsion paints. Emission factors of the two types of emulsion paints were determined by using a small chamber (20L) method and a large chamber (54m^3) method. The results obtained can be summarized as follows; 1) It was found that total VOC emission factors of the W1-grade emulsion paint were remarkably lower than those of the standard emulsion paint in both the small chamber test and the large chamber test. Effectiveness of the W1-grade emulsion paint on VOC reduction was confirmed through the experiment. 2) Emission factors of total VOC, formaldehyde and acetaldehyde showed almost same tendencies in both the small chamber test and the large chamber test except for total VOC emission factors of the standard emulsion paint.

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Although the behavior of rain drops near the surface of a building in driving rain are quite complicated according to the sizes of the drops and the air flow pattern around the building, a general relationship exists between average impinging angle of raindrops against the wall surface and the wind velocity that accompanies the rain. It can be of great value in estimating wetting characteristics of those walls, if we can express the relation in a simple equation. Shapes and sizes of stained areas that are left just below projections over a wall offer valuable information for the maximum impinging angle of raindrops against the wall. From the analysis of wind speed records during the rains which could have caused the stain patterns, certain range of constant C_<im> for the impinging angle-wind velocity equation was obtained.

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This paper proposes a method for the evaluation of seismic wave, considering more effective representation of destructiveness of seismic wave. Specifically, a seismic wave energy spectrum is newly defined by decomposing the seismic wave energy into the frequency domain, and a ground motion attenuation law for the seismic wave energy spectrum is proposed. The wave form through this representation, which is considered as the best one for design and assessment of structures can be established along with the temporal characteristics which are beyond the scope of this study. The proposed attenuation law is considered to be utilized for a probabilistic seismic hazard analysis in which one aspect of the seismic ground motion such as PGA or PGV has been focused so far.

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Equivalency between a linear viscous element and a bilinear viscous element is discussed based on their passive control effectiveness. Using such characteristics, a passively controlled system having the bilinear viscous elements can be converted to that with linear elements, thus, its seismic responses can be predicted based on simple linear theory. These are validated through numerous time history analyses over a wide range of viscous coefficient and relief load of the element, balance among the element, brace, and frame, vibration period of the structure, degrees of freedom of the structure, and phases and spectrum characteristics of earthquakes.

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We know the fact that almost all the people are killed by collapsed wooden houses in earthquake, but a precise estimation method for casualties hasn't existed in the field of earthquake engineering. In this paper we reconstruct the vulnerability function and damage index function for wooden building in order to estimate damaged building under the state that many people are killed. Combination of this function and Death Risk Function gives us the preventive information for individual and the precisely estimated casualties in wide areas for municipal prevention project.

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The objective of this paper is to propose a stiffness design method of additional storys of new seismic reinforcement system for existing multi-story building. The seismic reinforcement system consists of an additional single or multi-story building structure and an isolation story with appropriately tuned isolators and dampers. Then the system enables one to increase seismic performance of existing building with small or no structural reinforcement to existing part of the building. In this paper, proposed is an optimum stiffness design method of the isolation story based on a classical theory for tuned mass damper and a stiffness design method of addtional story(s) via hybrid inverse problem formulation. Several numerical examples are shown to demonstrate validity of the proposed design method. Elasto-plastic time history analyses under recorded earthquakes are performed to demonstrate efficiency of the proposed system.

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This paper presents seismic response analysis of high-rise buildings subjected to long-period strong ground motions predicted in Kansai area during large earthquakes along the Nankai Trough. Two steel building models, 75m and 150m in height and designed according to common practice in the 1970s early developmental stage in Japan, are prepared to simulate seismic response under predicted ground motions obtained from four different estimation methods and source models. Maximum response of models are investigated with respect to predicted sites, estimation methods, earthquake source, variation of magnitude of earthquakes and dynamic characteristics of structures. Demand of plastic deformation for steel moment frames and moment connections during earthquakes are also revealed.

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Since it is well known that the internal damping of many materials is comparatively frequency independent, an analysis model that can express such characteristics (called a hysteretic damping model) in the time domain is needed. Many investigations into this subject have been carried out, and it is indicated that the Biot model is the closest model to the causal hysteretic damping model at present. On the other hand, the author proposed a causal hysteretic damping model and confirmed the efficiency of the model in a previous paper. In this paper, the Biot model was formulated using the Prony series or the transform method. The efficiency of the proposed model and the Biot model was studied through the comparison of the characteristics of the impedance, the impulse response and the results of the time history response analyses of example problems.

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Imperfection sensitivity properties are investigated for an arch that has multiple member buckling at a limit point, which is classified as hilltop branching with multiple symmetric bifurcation points. The critical loads of imperfect structures are shown to be governed by a piecewise linear law of the imperfection parameter. Antioptimization problems are formulated to obtain the worst imperfection mode that most drastically reduces the critical load. A formula for the worst nodal imperfection as a linear combination of the critical modes is also presented. The validity of the formula is ensured by path-following analysis of arches with randomly generated imperfections.

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In excavation work on soft ground, the soil improvement method by buttress typed deep cement mixing walls is employed in order to prevent the earth retaining wall displacement. In the design of earth retaining structure, it is important to evaluate precisely the prevention effect of earth retaining wall displacement. In this paper, based on field measurement of earth retaining wall displacement and FEM analyses on buttress shapes and ground rigidity, the evaluation method of the prevention effect on earth retaining wall displacement with Winklerian model calculation is presented.

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The work presented in this paper is concerned with developing a consistent, systematic and convenient analytical method which enables us to simulate the complex stress-strain curve like one of a metal material. From the view point, various methods have been suggested and developed. Particularly the Overlay model has been used to grasp the characteristics of a complex material non-linearity problem qualitatively or to calculate a complex stress-strain curve numerically. Controversially, the Overlay model is costly to simulate an actual scale building structure because the Overlay model needs many virtual layers. Then, we propose the analytical method which is formulated by using macroscopic values which are derived from the Overlay model with various value of a yield stress microscopically. So we call the present model the Macroscopic evaluation method. The basic equations for our method are compared with ones for the Bounding surface model. Then we examine the validity of uncertain postulates introduced in the Bounding surface model. Finally, numerical examples are shown to verify the suggested macroscopic evaluate method.

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This paper aims to show the applicability of the scissors system to the temporary structure. Since the traditional scissors has the simple "deployable mechanism", it has the merit that it is possible to save the time of the assembly work. On the other hand, in the traditional scissors there are structural problems which are not only that the stiffness of structures after completion is not sufficient to resist load but that the bending moment generated at the main members is relatively large. To solve these problems, in this paper, authors propose String Scissors Structure (SSS). SSS is reinforced with the strings, and it is applied to the truss which the bending moment doesn't occur to. Authors demonstrate the structure property of SSS, and propose new concept of method of reinforcement and manpower construction.

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Instead of the wooden tenon, steel tenon-bar connecter which is inserted into the joint of the horizontal member and column and fixed with drift pins have been suggested. The combined stress from the shear and tensile force in the joint has been considered to be transferred through the steel tenon-bar connecter and thus the resistant force of the point is necessary to be verified. The present evaluation formula serves as an underestimate compared with experimental result. To overcome such underestimation, in this paper the evaluation formula for combined stress in the joint of horizontal member and column connected by steel tenon-bar connecter which is attached to the compressive brace has been derived based on the mechanics model, and the validity of the formula has been verified by experiment.

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In this paper we studied the brittle fracture of bolt connection with Japanese larch glulam loaded perpendicular to the grain by based on local fracture approach. First we thirled two types bolt holes with a drill press and studied the conditions around the hole. Then we checked that there were cracks around the hole. The length of that cracks differ acceding to the bolt diameter. Next we conducted tension tests of glulam, tension tests with double notched glulum and tension tests with bolt joint specimens. As results, we understood that there were two fracture types in bolt joint specimen. We checked brittle fracture in the specimens which end distance was small and ductile fracture in the specimens which end distance was large. We studied the fracture in the first case with the claevage fracture stress. We studied the boltjoints strength with FEM analysis. In that analysis model, we replaced the crack around the bolt hole into the equivalent crack. As results, we can predicted the single bolt joint strength with reference to the edge distance, those joints fail in a brittle manner.

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Tensile test of full-size lumber with square and round section, used as column and beam, has never been conducted because of the difficulty of loading. This study aimed to develop full-size tensile testing method of structural lumber and to evaluate several mechanical properties of lumber. Specially designed fixing jig, transmitting sufficient axial force to lumber, was developed. Although many knots were observed at the surface of specimens, the maximum tensile stress is much higher than the standard material stress of normal grade material by AIJ code. As the results, knot was found not to be defect for tensile loading.

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Current seismic resistant design strategy, including Performance-Based Earthquake Engineering (PBEE) requires accurate estimation of the seismic demand and capacity of structures, for which non-linear analysis has been employed for several decades in research and practice. However these analyses on member-basis have been almost indifferent to member models which represent damage distribution along the member. Girberson's one-component model is the most popular one which considers concentrated plastic rotational hinges at member ends. But the assumption is not necessary accurate enough for members of reinforced concrete, because plastic damage distributes due to cracking all through the member. In this study, results of non-linear static analysis (NSA) and non-linear dynamic analysis (NDA) are compared for four different member models. Girberson's one-component model is compared against the other member models for structural response parameters including, story drift demand and member force demand. It is revealed that one-component model overestimates maximum drift demand larger than compared different member models In NSA. Even including higher modes in lateral force distribution does not change the trend. However, member force demand estimated by the one-component model is larger than that by the other models. In NDA, one-component model underestimates the unevenness of drift demand smaller than other models and overestimates the unevenness of member force larger than other models in the intermediate stories.

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It is considered that in the buckling-restrained bracing, its core plate is stiffened with a restraining part to prevent buckling. In reality, however, high-order buckling mode occurs in the core plate, when the buckling strength of the core plate is approximately equal to the yield strength of its cross-section. The results of testing of buckling-restrained braces conducted by the authors indicate that in the final phase of the testing, local deformation occurs in their core plates, and at this point, their load-bearing capacity often starts to decline. In order to understand in full detail the mechanism of buckling observed in the core plates, more specifically, how high-order buckling mode develops into local deformation in some core plates, the authors conduct strain measurement using strain gauges attached to the core plates and analyze the obtained data. The authors also consider the relationship between high-order buckling mode and the performance aspect such as energy absorption rate.

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A formula for evaluating an effective length factor of a column in a symmetrical frame with bracing is proposed. First, an analytical model is defined as a portal frame with a bottom beam and bracing by showing the model is equivalent to a partial frame model of a symmetrical multi-bay multi-storey frame with bracing. Then an equation for an effective length of the column is obtained by using the energy method. The effective length obtained by proposed formula agrees well with the correct value obtained by using the buckling slope-deflection method. And a procedure for calculating the effective length factor of the column in the frame with bracing is presented.

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The objective of this study is to assess the local elasto-plastic behavior of a beam-to-column connection between a concrete-filled square steel tube column and a steel beam, used in a perimeter moment resisting frame system. The connection is equipped with a side stiffener and a divided external diaphragm. This paper describes experimental results and an analytical model for predicting the load-displacement relation associated with this beam-to-column connection. Parameters investigated in the tensile tests include the side stiffener configuration and the inplane beam eccentricity. The analytical model is developed by superposing the strength of the side stiffener and external diaphragm on the load-displacement relations for a tube flange. The tube flange is modeled as a grid beam with a tetra-linear load-displacement relation. The analytical method is found to agree approximately with the experimental results up to large deformations.

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A numerical simulation of the fire resistance test of large steel columns is presented. The experimental investigation into the fire resistance properties of axially loaded large steel box columns were described in Ref.(1,2) by authors. In this paper, a procedure for a one-dimensional finite element of nonlinear numerical analysis was applied to simulate thermal deformation, which is described as an elastic-plastic-creep, of steel columns as they are subjected to high temperatures. And the results of the calculations clearly show that numerical analysis can be used to provide accurate predictions of the deformation characteristics of columns at high temperatures, when an appropriate mechanical model and creep strain data of steel materials at high temperature are used.

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Predictive method of the fire resistance of Japanese traditional bare-timber soil wall construction is proposed assuming its general dependence to the buckling of the posts due to the eccentric reduction of the post section by charring and the reduction of the Young's modulus of wood at high temperature. The constraint coefficient in the Euler's buckling formula has been determined for this construction according to post compression tests using post specimens engraved to reproduce the mechanical performance after design fire exposure times. The validity of this method has been verified against a series of wall furnace tests using one-story tall wall specimens.

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