In this study, a series of experiments has been carried out to examine the properties of concrete using recycled aggregate made from used concrete pole. As the result, followings has been found. 1) The quality of recycled coarse aggregate made from used concrete poles corresponds to the recycled aggregate class M. 2) The hardened properties of recycled aggregate concrete can be significantly improved by the centrifugal compaction and the steam curing. 3) There is a possibility that recycled aggregate made from used concrete pole can be applied for the concrete utility pole, if natural aggregate is replaced with a part of recycled aggregate.

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In this study, experimental investigations were conducted regarding shear reinforcing effect of reinforced concrete (RC) beams by means of continuous fiber reinforced plastics materials such as carbon fiber sheet, polyethylene fiber sheet and polyethylene fiber net. The experimental results on ultimate shear strength of the beams were compared with calculations based on design and construction guideline of continuous fiber reinforced concrete published by AIJ. As a result, it was shown that shear reinforcing effect were obtained regarding ultimate shear strength of the RC beams strengthened with continuous fiber reinforced plastics materials, and the design guideline gives reasonable accuracy for calculation of ultimate shear strength of the beams.

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In this paper, the electromagnetic wave character of building materials are measured by the parallel wire line method and the parallel wire line for penetration wave, and the following have been examined.
1) It was possible to classify building materials into three types, (1)the materials which has the large reflection loss, (2)the materials which has little reflection loss and large reflection and (3)the materials which has little reflection loss and large penetration.
2) The amount of reflection increases by rising of the water content of cement materials, and the amount of penetration decreases.
3) The relation between the modulus of attenuation and the absorption was measured.

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The measurement wind velocity on the rooftop of the tall building is usually utilized as a reference wind velocity. However, after many new tall buildings have been constructed around the specified tall building, it becomes difficult to use the rooftop data as a reference. While, the wind velocity predicted by the meso-meteorological model (MM5) without the urban-canopy model has been little affected by surface shapes of buildings on the ground and expected to be accurate at sufficiently higher position. This paper examines the regional representativeness of MM5 wind velocity data by comparing the full-scale measurement data at open area. Also, in the case of measurement point within the urban canopy, rooftop wind velocity computed by large-eddy simulation (LES) is estimated by matching MM5 wind profile. The method determining an appropriate height for a reference wind velocity is provided.

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In developing countries of seismic area, many people have to live in traditional masonry houses of adobes, bricks, stones and concrete blocks. Though collapse of the houses is one of the most tragic losses of human lives, shift of the houses to construction based on modern engineering is difficult by socioeconomic reason. The authors have been developing a rocking pillar base isolation system suitable for masonry houses. Seismic performance of the system was discussed by vibration test of reduced scale specimen in the previous paper. In this paper, shaking table tests and time integration method of the system are summarized. Based on the obtained test results, effectiveness of mass-eccentricity of superstructures on seismic performance of the system is discussed. Also, accuracy of the analytical method is demonstrated via numerical simulation of the shaking table test.

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The authors have proposed the single-tuning viscous mass damper system based on fixed points theory. Vibration control effects of singletuning type system are very sensitive to changes of parameters such as the natural frequency of the controlled object and the damping coefficient of the absorber itself. In this paper, response control method using multi-tuning type system with diversified natural frequencies is proposed. It is shown that the multi-tuning type system proposed herein is considerably effective in improving the reduction efficiency of the response magnification factor than single-tuning type system.

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Site amplification adjacent to abrupt irregularity in deep underground structure is important issue for ground motion evaluation as we learned from the lesson during the 1995 Kobe earthquake. In Osaka City, there exists Uemachi Fault travelling down through densely populated area along with submerged step-type underground structures, which could be another factor for damage belt. This paper describes 3D & 2D effects of submerged step-type underground structure on ground motion amplification. Transfer functions at the site, where ground motions are largely amplified in the 3D structure, almost coincide with those in 2D structure due to obliquely incident SV-wave and is independent from faulting parameters, e.g., rupture process, rupture velocity. Parametric study using 2D model reveals that ground motion amplification occur adjacent to step-type boundary even in the high frequency range, which could affect nonlinear responses of short period buildings.

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This paper examined efficiency of temperature parallel simulated annealing (TPSA) to obtain optimal arrangements of base-isolation devices for buildings. This technique uses simulated annealing (SA) in parallel, and is more excellent than past SA. Two buildings which were built in actual were selected to examine the optimal design. Buildings, those base-isolation devices were arranged by SA and TPSA, have better earthquake performance than that in actually designed buildings and difference in the performance of buildings designed by two methods were very small. Consequently, the search performance that TPSA is more excellent was shown.

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This paper proposes a finite element method for nonlinear sloshing analysis of the liquid storage tanks with the single-deck type floating roof. The elastic finite elements with geometrical non-linearity are applied on modeling the floating roof, and the liquid elements are formulated based on the potential theory and the variational principle. The interaction problem of the elastic body and the fluid is formulated based on the variational principle, therefore the equilibrium equations are simply derived.
The 100,000kl tank struck by the 2003 Tokachi-oki earthquake is modeled for the numerical example, and the seismic response analysis is performed. As this result, it is found that the high-order mode vibration, of which deformation is the 1st radial mode and the 3rd circumferential mode, might occur as the second mode vibration grows on the floating roof, and large stress such that the pontoon is collapsed might appear in the floating roof.

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Centrifuge model tests of belled pile and straight pile in sand were performed in order to investigate the characteristic of uplift resistance behavior of belled pile embedded within deep deposits. A numerical analysis with finite element method was also carried out to clear uplift resistance mechanism of belled pile. The results of this study can be summarized as follows:
1. As centrifuge model test results, the uplift resistance force of belled pile was larger than that of straight pile with the same in axial diameter.
2. The thickness of influence zone in the ground to uplift resistance of bell enlargement was a range of between 2D to 3D (D:diameter of bell enlargement ) from the tip of belled pile upward.
3. It is indicated that the uplift resistance force of bell enlargement increased with a rise in the shear stress on sliding surface near the pile shaft caused by increasing of the lateral pressure in the ground.

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Seismic responses of large glass walls are deeply affected by the dynamic properties of their sealing materials. However, their dynamic characteristics have been not confirmed because of their being treated as non-structural elements. The authors have studied on the dynamic properties of glass sealing material with dynamic experiments, and proposed their precise hysteretic models in the previous paper. In this study, dynamic shaking-table tests on glass wall mock-ups are carried out, and their in-plane dynamic characteristics and seismic response are confirmed. Their results are compared with analyses using proposed hysteretic models, and their validities are discussed.

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Being insufficient seismic capacities of the buildings not designed in accordance with the current code, it is politically encouraged to improve their structural properties which are specified stiffness, strength and ductility. Conventionally, bare frames are strengthened using of steel braces with perimeter frame and connected by the use of many dowel anchors and grouting mortar. We performed the lateral loading tests of R/C framed specimens retrofitted with steel braces without the anchors to enhance their strength and stiffness.
On the basis of the proposed shear resisting mechanism, new strengthening methods called anchorless system have been developed by using friction at the joint of a flange of the perimeter frame and an existing beam. A means to evaluate the stress transfer based on the resistance of friction were presented as well as the results obtained from cyclic push-off shear tests of the joints subjected to variable constraining forces.

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The strength and cracking patterns of retrofitted carbon fiber chip reinforced concrete cylindrical shells were investigated, both experimentally and numerically. Three kinds of retrofits to the damaged shells were adopted in this paper: Precut retrofit, filler retrofit and sheeting retrofit. Precut retrofit was defined as the method worked to cut the region adjacent to the damaged boundary to be smoothed in order to avoid the stress concentration. Filler retrofit was defined as the method made by filling the region with the non-contracted mortar after applying by pecut retrofit. Sheeting retrofit was defined as the method worked on the surface of the region covered with the carbon fiber sheets after applying by filler retrofit. The concrete was artificially damaged before it was evaluated by a loading experiment using a one-point concentrated load, and the retrofit applied to the damaged shells was realized by the three kinds of retrofitting methods described above. In the experimental study, a static point load was applied perpendicularly onto the retrofitted cylindrical shell specimens until the cracking pattern was obtained by applying the maximum force. In the numerical analysis, nonlinear finite element analysis to model the effects of concrete cracking and tension stiffening was applied. The strength and cracking patterns of the retrofitted carbon fiber chip reinforced concrete shells are discussed based on the results of the numerical analysis and the experiment.

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Some researchers have been studying the strength of joints loaded perpendicular to grain in latest years. Some connections fails in brittle or ductile manner and its fracture features depend on the size of joints and bolt diameter. But evaluation the fracture of wood is very difficult, so some evaluation method was proposed.
In the past study, we analyzed the strength of bolted joints with FEM analysis, and we understood that the cleavage fracture stress is useful to evaluate the strength fractured in brittle and that J-integral has a possibility to evaluate the crack initiation.
So in this study, we applied J-integral obtained from CT-tests of FEM analysis to bolted joints loaded perpendicular to grain fractured in ductile manner, and the cleavage fracture stress to the joint fractured in brittle manner as same as before. As the results, we can calculate the strength of joints loaded perpendicular to grain by two fracture patterns.

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A composite member that thin steel plate was sandwiched between two Glulam-Japanese-cedar using friction connectors was developed. In this study, shear test results of friction connectors are reported because the shear stiffness of the friction connectors is important to use the equations for estimating the strength of composite member. Friction connectors are shear connector modified to strengthen combined Glulam-Japanese-cedar and steel compared with shear-ring connector. In this paper, shear performance of connector alignment of multi-friction connector is examined.

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The theoretical solution of crack width in reinforced concrete members has been proposed by the authors in the previous paper, Part1. However, the theoretical solution is difficult to use routinely because the two parameters in the solution, tensile splitting strength of concrete and the bond stiffness, should be obtained from experimental result. Therefore, this research proposes the formula by simplified the theoretical solution. The practical formula for the tensile splitting strength from compressive strength was proposed by the previous study. In order to discuss the bond stiffness, the pullout test is conducted to propose the formula for it from compressive strength and diameter of reinforcing bar, which are the influence factors for bond stiffness. To use the formulas for tensile splitting strength and bond stiffness, the theoretical solution is simplified. The calculated relationships between reinforcement strain and crack width which are led by the proposed formula show good agreements with the theoretical solution.

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This paper proposes a supporting scheme for structural design of steel frame structures by using the structural optimization method. Most of steel structures are composed of the standardized members produced at the factory. In order to take such situation into the process of structural optimization, the structural optimization scheme through the usage of Genetic Algorithm which can easily deal with discrete variables is formulated. Furthermore, multi-objective optimal design method to obtain the Pareto solutions considering both structure's safety and economy by using Multi-Objective Genetic Algorithm is proposed. Through numerical examples, it is shown that the present scheme is useful for designers as a valuable proposal scheme especially in the beginning stage of structural design.

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RC coupling beams with low-yield-point steel web panel in the mid-span (coupling beam damper) have been developed and applied to actual buildings. Cyclic loading tests had been performed, resulting that the coupling beam dampers provided the stable hysteretic performance and load carrying capacity did not deteriorate up to 1/20 of drift angle.
In this paper, finite element analysis has been carried out to evaluate the shear buckling strength of the coupling beam damper. It is verified that the low-yield-point steel web panel (with width-thick ratio of about 15) of the coupling beam damper is thick enough to avoid shear buckling. Restoring force characteristics of the coupling beam dampers for structural design is also proposed. An appropriate modeling of RC parts is important to represent the total structural performance.

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The number of recorded seismic ground motions is increasing rapidly. However, the statistical data for the structural designers to determine the design ground motion for a specified site remain still far incomplete. While the structural damage may increase as the seismic energy input increases, the structure can remain uncollapsed as far as the sufficient energy absorption capacity is secured. Therefore, it is essential to prepare a sufficient energy absorption capacity for the structure to meet the unknowableness of the seismic input. In this paper, a set of seismic input is considered to cover the unknowableness of the seismic input, and the required strength and the maximum deformation is estimated by applying the energy approach. Framed structures are taken for example and it was found that the required base shear force coefficient can be determined uniquely regardless of the level of seismic input and the structural type(steel structure or reinforced concrete structure).

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The paper is intended to summarize findings from fire resistance tests on composite beams with ends restrained against rotation. The specimens were comprised of H-shaped steel beam and overlying composite slab with profiled steel decks, with studs at the interface. A total of four models were tested. The test parameters included the level of load. Based on the test results, a new formulation is proposed to calculate with a good accuracy, the flexural strength under positive moment on the basis of the plastic theory taking account of the heat-induced degradation of steel / concrete materials and shear capacity of studs in the positive moment area, and the local buckling strength under negative moment on the basis of the models taking account of the post-peak strength behaviors which were obtained from stub-column tests.

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