In recent years, various kinds of aggregates are being developed for the purpose of resources recovery of solid waste. Generally, these types aggregates contain microscopic porosity in these matrixes. These aggregates show many different properties comparing with conventional artificial lightweight aggregate, such as chemical composition, manufacturing process, internal structure and external surface structure and external surface, textures. Variation of properties, density, absorption, strength, etc of porous aggregate are caused by reasons above-mentioned. According to our series studies, it was observed that properties of porous aggregate, density, absorption, strength, etc can be evaluated by porosity as common index, and porosity has a high correlation with three properties. Based on the past above investigation, this study was carried out in these experimental series. Series I : Characteristic of porous aggregate Series II : Correlation of porosity and mechanical properties of mortar and concrete containing porous aggregate. Series III : Correlation of porosity and mechanical properties of mortar and concrete containing normal aggregate and porous aggregate. Volume and radius of porosity, density, absorption, strength of aggregate in series I, volume of porosity, density, compressive strength, Young's Modulus of mortar in series II, volume of porosity, density, compressive strength, Young's Modulus of concrete in series III were measured respectively. Porosity of aggregate, mortar and concrete, density, compressive strength, and young's modulus are measured.

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In this study, the rheological characteristic of the high-fluidity concrete was evaluated by the coefficient of viscosity and the shearing yield value that was measured by using the J shaped flow test. The effects of the mix proportion factors such as the water- cement ratio, the aggregate-cement ratio, the sand percentage and the addition quantity of the super plasticizer and the segregation agent on the rheological constants of the high-fluidity concrete were investigated. It was clarified that the shearing yield value of high-fluidity concrete can be made low by setting water-cement ratio and the sand percentage to the proper value, by setting the aggregate-cement ratio small, and the viscosity of high-fluidity concrete can be adjusted with the addition quantity of the segregation agent.

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Although laser is widely used for cutting, welding and surface treating metals, application of the laser for processing inorganic architectural materials is quite rare. In this study, the feasibility of using laser energy to form glass layers on mortar panels with zeolite aggregate was assessed. The effects of mix composition and laser irradiation parameters on the characteristics of the glass layer and on the flexural strength of zeolite mortar panels were investigated. It was found that the optimum mix composition and laser irradiation parameters for obtaining panels with high flexural strength and stable glass layers were as follows : zeolite particle size = 0.6 to 1.2 mm, W/(C+Z) = 25 to 30 %, cement/zeolite mass ratio = 1 : 2 to 1 : 3, Laser power = 1kW, beam diameter = 200 mm and work travel speed = 750 mm/min.

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We tried to establish the quantitative value of tiled walls' accuracy of finishing by using CI, which is the quantitative value corresponding to the conspicuousness of the irregularity of a tile. Human perception on tiled walls' accuracy is influenced by not only a tile whose CI is biggest of the wall but also other tiles whose CI are rather big. So, we prescribed the measuring area according to the visual field, and measured CI of each tile from there. By weighting and adding them in big order, we established 'AF' as the quantitative value of tiled walls' accuracy of finishing.

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The purpose of this study is to present the relative evaluation method of unevenness of floors from a viewpoint of trouble to human caused by vibration on casters. First, we carried out sensory tests to make evaluation scales of vibration on casters such as wheelchair and stretcher. Next, we developed the specialized caster. This caster could detect the acceleration on casters caused by unevenness of floors, corresponded to evaluation scales. Finally, we presented the relative evaluation method of unevenness of floors, dealing with maximum amplitude of acceleration detected by the specialized caster.

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The outline of this study is as follows : The first, sensory tests were carried out to make psychological scales of suitability, fatigue and effect to keep the physical fitness in walking on "Loose-Surface". And it was cleared that there were intimate relations among these psychological scales. The second, biomechanical and physiological parameters in walking were investigated using force plate, electromyogram and heart rate monitor. As a result, it was cleared that "Loose-Surface" wasn't suitable for walking and was fatigable, but it was effective to keep the physical fitness. Also it will be careful to use "Loose-Surface" for physically handicapped.

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This paper describes the derivation of high order expressions that narrow the reliability bounds for parallel systems. The reliability bounds for general systems are slso improved in consideration of the correlation coefficients. The reliability bounds for parallel systems are employed to develop those for series systems and vice versa. Finally, the performance of proposed bounds is almost certainly confirmed through several typical examples.

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As a building becomes higher and more slender, the hysteretic damper is often installed for mitigation of oscillations. However in the case that the oncoming wind velocity almost reaches the critical range of the onset of aeroelastically unstable phenomena, we encounter the unsolved trade-off problem such that a damping performance of the building surely increases, but the natural frequency tends to shift lower and resonant velocity becomes lower. So we carry out the wind tunnel experiment in order to estimate the across wind oscillations of a tall building with hysteretic damper, which is placed in the atmospheric turbulent boundary layer. We also estimate a hysteretic damping performance by investigating the relation between the static load and the deformation of a building model. Finally we compare the inelastic response under the hysteretic damping conditions with the elastic response under the equivalent viscous damping conditions. On the basis of their relation, the performance of hysteretic damper on a tall building is discussed.

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The objective of this study is to investigate the seismic performance of a structure supported on pile foundation. Pile foundation response during earthquake is strongly affected by nonlinear interaction of soil and superstructure. Earthquake response analyses are conducted to clarify the effect of soil-pile foundation-superstructure system to the performance of pile foundation. Pile responses are evaluated using the nonlinear relationship between bending moment and curvature dependent on the axial force. Performance of pile foundation is discussed on the basis of the curvature of piles and the displacement at the pile head.

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In this paper, the characteristics of horizontal complex stiffness of the embedded foundation are investigated by applying the three-dimensional thin layer element method. For an embedded foundation - boundary soil zone - outer soil zone system model, the non-linearity of the soils within the boundary soil zone around the embedded foundation are analyzed by the use of the equivalent linearization method. The relationships between the strain, shear rigidity and damping constants of the soil are evaluated by the use of the Ohsaki-Hara Model.

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The mixed assumption theory can propose static and dynamic theory which satisfy the boundary conditions of upper and lower surfaces of the plate. In this paper, we formulate general higher-order theory of plates under assumption of displacement and stress components of the plate thickness distribution by using the dynamic variation principle of the mixing type which made specialized the basis of Hu-Washizu. This equation was examined through static and dynamic solution example, and as well was studied the influence given to the solution precision if it satisfies or not boundary condition of upper and lower surfaces of the plate.

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Structures are made by assembling several blocks that we can handle by construction machines and ourselves. Arrangement of the blocks is very important in the construction planning. The arrangement is made by trial and error, considering many conditions. Therefore the work of the planning is very difficult It is also difficult to judge fitness of a decided arrangement by a usual planning method. In this paper, two analytical methods using genetic algorithms are introduced into two optimum problems of dividing structures into blocks under construction : divisions of plate structures and truss structures using panntadome system. The results of analytical examples verify that the proposed analysis can give an optimum arrangement of blocks and could plan the arrangement easily.

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Solution form proposed in this paper derived by using Moore-Penrose generalized inverse based on the displacement method can apply even to the problems on the singularity of the stiffness matrix. By solving the elastic and the rigid-body deformations of retractable structure, the exact equivalent linear treatment of the shape-finding and the stress analyses of tension structure such as cable structure, and also investigating the bifurcation phenomena of a shallow arch structure, the advantage of that there is the condition for the existence of a solution in the solution form itself is illustratively presented with the theoretical proof.

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This paper continues from the previous thesis (Part 1). It presented experimental result of model earthquake-proof piles guarded with short outer sheath pile and also a calculation method for the pile system of this type. In this study, we calculate the horizontal behavior of earthquake-proof pile composed with a PHC-pile (main pile) and a steel pile (outer pile). It takes into account the non-linear property of bending rigidity of both piles subjected to the vertical load in an earthquake. From these results, it was found that the seismic horizontal capacity of the earthquake-proof pile in both short time and ultimate state could increase remarkably in comparison with an isolated main pile, even if the outer sheath pile length is set up comparatively short.

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In the top-down construction method, structural steel columns are embedded in cast-in-place concrete pile. Axial force from steel column to concrete pile is transmitted by the following resistances, bond resistance between steel column and concrete pile, shear resistance of stud connectors and bearing resistance at the end of the steel column. In this paper, 24 static loading tests were carried out. The main parameters were embedded length, section of steel column and the number of stud connectors. Based on these test result, ultimate strength of concrete pile head is evaluated as the sum of resistance strengths modulated by effective factors.

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In this paper, the relation between the wall-length ratio of Japanese wooden houses and the ultimate horizontal resistant force considering the stiffness of both floor and non-structural walls is discussed. The analytical Model has the restoring force characteristic composed of the floor, bracing bearing walls and non-structural plaster board walls. The results may be summarized as follows : The wall-length ratio considering both structural walls and non-structural walls is nearly equal to the wall-length ratio considering only structural walls. The lower limit of the ultimate horizontal resistant force is estimated using the wall-length ratio considering only structural walls.

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Lateral buckling is one of the most important limit states for glue-laminated wood beams with deep depth and long span. The purpose of this paper is to present design formulae for lateral buckling strengths of glue-laminated wood beams. Lateral buckling tests for three sectional types of laminated wood beams are conducted. Based on the test results, it is shown that the lateral buckling strengths agree well with the strengths based on the classical elastic theory for beams. The variations of the lateral buckling strengths are presented based on the first-order second-moment method for the calculation of resistance factors of partial safety factor formats.

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As the third part of an integrated theoretical and experimental study of earthquake-resisting performance of square tubed concrete columns, this paper deals with effect of shear span ratio (a/D) of columns on the seismic behavior as well as confining effectiveness of square steel tubes. Fourteen reinforced concrete columns having two kinds of shear span ratios of 1.0 and 1.5 were confined by square steel tubes with five kinds of wall thickness. These columns were tested under reversed cyclic lateral force while subjected to constant axial load. It is shown that as confined in square steel tubes having same wall thickness, the column that has shear span ratio of 1.5 behaved in a much more ductile manner than the short column whose shear span ratio is 1.0. To make the short columns under axial load with n=0.33 and n=0.67 ductile enough, use of thick steel tubes with B/t=43 and B/t=28 were needed, respectively. Experimental results also indicate that the ultimate drift ratio of the short column with a/D=1.0 was about 0.01 rad smaller than that of the column having a/D larger than 1.5 when the steel tube with same wall thickness and the concrete having same compressive strength were used.

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Beam specimens of lapped splice bars with high-strength concrete were tested to determine the bond splitting strength at the critical section of a beam, under shear-bending stresses for 10 specimens and under pure bending stress for 3 specimens. Shear-bending load was applied to the longitudinal lapped splice bars of a beam of high-strength concrete until they fracture in side-split mode. The main variables tested are lapped splice length and transverse reinforcement ratio. The bond splitting strength of shear-bending test specimens is larger than that of pure bending test specimens. The existing equation of bond splitting strength, which takes into account of shear-bending stress, was proved to give satisfactory estimation of the bond splitting strength of lapped splices in the shear-bending test specimens.

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FEM analysis are performed to investigate the local behaviors of tubular steel towers reinforced by ring-stiffeners under two different loading conditions. The effectiveness of these results are evaluated through empirical studies using real-scaled models together with the preceding results regarding the tubular steels stiffened by both of ring-stiffeners and gusset plates. The derived conclusions are : (1) the effects of the axial forces on the yield strength of the stiffened steels are investigated. (2) the yield strength of a ring stiffener increaces under loads in a single direction while it decreases when loads are in multiple directions. (3) the stress distribution in ring-stifferners is able to be effectively evaluated by the proposed method.

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In this paper, evaluation of seismic performance of moment resisting steel frame using the shaking table test is discussed. Specimens are moment resisting steel frame with or without use of the buckling resisting brace. Three different type waves (El Centro, Hachinohe and Kobe) are inputted in the shaking table with two levels (level 1 = 25kine, level 2 =50kine). As a result of the test, we have confirmed that moment resisting steel frame with the buckling resistant brace can greatly reduce both the deformation angle and maximum strain at the edge of the beams in their mainframe. It was also shown that a capacity for energy absorption and fatigue properties of the damper decreases when set within the frame. However, the buckling resistant brace within the frame has enough capacity to resist level 2 earthquakes more than 30 times.

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Many fractures in beam-to-column connections of steel framed structures occurred in Hyogo-ken Nanbu Earthquake. In this paper, we notice on the influence of composite beams as a factor of such fractures, and investigate the deformation capacity of composite beams by a series of experiment. Main conclusions are as follows. (1) The deformation capacity of composite beams is remarkably lower than steel beams without slabs. (2) Section properties and loading histories have little influence on the deformation capacity of composite beams. (3) When composite beams are subjected to a positive bending moment, following phenomena are observed : a) Strain is concentrated to lower flanges. b) Plastic deformation is concentrated to narrow area near the beam-to-column connections. These are the factors which reduce the deformation capacity of composite beams.

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The 1995 Hyogoken-Nanbu Earthquake gave us a lesson that brittle fracture of beam connections may not necessarily knock down steel frames of buildings. This experimental study is purposed to clarify the reasons why steel frames could stand after such serious damage in beams during the earthquake. It was found that the most promising factor which could support the buildings after beam fracture is the backup of reinforced concrete slabs connected to steel beams with studs. Even after complete fracture of beam sections connected to a column, the beam ends could carry negative bending moment by a couple of tensile force in reinforcing bars in the slab and compressive force in the beam's lower flange which has a post-fracture contact with the column.

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The previous paper proposed a seismic design procedure to estimate the ductility demanded of beams in steel frames that sustain overall collapse mechanisms. In this paper, a method is presented to predict a collapse mechanism that can form with the greatest probability in a frame structure under severe earthquake excitations, and the amplification factor of the ductility demand is determined based on the predicted collapse mechanism. Seismic responses of steel frames sustaining various collapse mechanisms are examined numerically. The results of the proposed method favor the overestimation of ductility demand for frames sustaining partial collapse mechanisms in a few stories but the approximation of the upper limit of numerical results.

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In a recent study, it was clear that the beam with large web slenderness has enough plastic deformation capacity for seismic design. But the large deformation behavior and the collapse mechanism of these beams have not been cleared. In this study, the collapse mode and that deciding the maximum load are investigated by experiment study and numerical analysis. As a results, it is clear that the ratio of the shear strength to bending strength of the beam is very important factor for the plastic deformation behavior. And the plastic deformation capacity of the beam is estimated by using the ratio.

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The fracture of tubes following cyclic local buckling should be one of the important failure modes with regard to the deformation capacity of concrete-filled tubular (CFT) beam-columns under severe earthquakes, so that such members under a loading condition of low-averaged but widely-fluctuating axial loading should frequently fail by this failure mode. However, the failure mode has not been fully investigated. From this point of view, the experiment was conducted on the CFT beam-columns under cyclic axial loads and horizontal loads. The experiment showed that (1) the failure mode of every specimen was the fracture of a tube after local buckling ; and (2) the fracture could be successfully predicted by the authors' fracture prediction formula.

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Seismic response and damage of concrete filled steel tube frame (CFT frame) are investigated in relation with the column over design factor (COF) of it. The numerical analysis method to predict the damage of CFT frame under strong ground motion is obtained by introducing the damage factors of steel tube crack and local buckling of CFT column. By the use of the presented analysis method the seismic responses of CFT frame subjected to the ground motions recorded in Kobe (1995) and El Centre (1940) have been calculated and the damage factors of CFT frame to collapse dynamically are obtained quantitatively. From the results it is shown that the calculated damage factors of CFT frame are closely related to the value of COF and COF=2.0 is proposed as the critical value of COF in the earthquake resistant design of multi-story CFT frame.

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A finite element model for bolted beam joints and a way to incorporate it into an existing FEM frame analysis have been developed to find the detailed histories of stress distribution both inside and outside the joints of frames under increasing member temperatures. Observing a series of computational results, it is found that the ultimate temperature can be approximated primarily by the simple plastic theory, whether a heated frame has bolted beam joints or not. It is also found that the residual post-peak shear strengths of bolts, whose existence seems expectable under elevated temperatures, help the ultimate temperature of a frame with bolted beam joints to increase to a significant extent.

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This paper is concerned with the identification analysis of structural damage detection on the unit-linked floating structure model based on fluid-coupled free vibration equation and filtering algorithm. The problem of structural damage detection is formulated as an inverse problem in structural engineering. The formulated inverse problem must be analyzed under the consideration of stochastic properties on the responses of system because the observations of the system are usually measured in the presence of noise. The filtering algorithm has been well known as the solution method that is able to consider stochastic properties. In this paper two kinds of filtering algorithm, namely the extended Kalman filtering algorithm and new filtering algorithm based on the projection filter, are employed in the identification analysis. The coupled natural frequencies used as the observations and stochastic properties of system responses adopted the data obtained by experimental modal analysis.

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