Prediction system for compressive concrete strength in aged structural member is proposed. This system is composed of models of rate of hydration, cement paste phase composition, heat production, specific heat, compressive strength, vapor desorption isotherm, coupled heat and moisture transfer. Each model is verified through experimental data. This system is aiming for the structural member which can not be accessed or can not be evaluated by the core sample test. Using non-destructive data or quality control sample's data, this system might illustrate the distribution and development of concrete strength in structural member properly. From the calculation results for a concrete member exposed to high temperature condition, strength development as well as distribution is quite sensitive to the boundary condition, and this concludes that the evaluation of structural member under such special condition needs precise boundary conditions.

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The purpose of this research is reducing the cracks produced in the plastering mortar that has contraction restrained by ground concrete about the outer wall and floor component of reinforced concrete buildings. It tried to evaluate the relation between the construction time of plastering mortar and the small crack produced on the mortar surface by this paper. The examination object which finished in the middle of the month every month of one year, and constructed mortar was exposed to the outdoors and indoor using the small concrete with plastering mortar specimens, and the generating situation of a crack was observed. Consequently, it was experimentally shown clearly that small cracks become easy to produce the time when temperature falls in one month after the mortar plastering.

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The 2011 off the Pacific coast of Tohoku Earthquake (M 9.0) is the greatest earthquake in Japan. Analysis of GPS network, such as GEONET by Geospatial Information Authority of Japan, has revealed the crustal deformation distribution due to the earthquake. On the other hand, the crustal deformation distribution can be estimated from the displacement waveform calculated by integrating the accelogram observed by strong motion seismometer. This method would be used complementary with GPS analysis. In this study, we calculated the crustal deformation distribution due to the 2011 off the Pacific coast of Tohoku Earthquake from the accelograms recorded on strong motion observation network K-NET and KiK-net by National Research Institute for Earth Science and Disaster Prevention. The crustal deformation distribution calculated from strong motion records is consistent with that by GPS observation. In addition, the displacement waveforms estimated from strong motion records are in good agreement with that from 1 Hz GPS analysis.

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Considerable differences are sometimes observed among the response spectra of ground motions synthesized by fault model under the same fault parameters. The causes of variation of response spectra are classified into two factors. The one is the random nature of fault rupture process, and the other is problem issued from synthesis method itself. The variation caused by latter factor is undesirable in practical use. This paper presents the method for the direct evaluation of average response spectrum by stochastic Green's function method. In the proposed method, the element earthquake motion is not transformed into time domain using random phase, and the average response spectrum of target large fault is directly evaluated in frequency domain. The average response spectrum can be evaluated without variation because the present method does not include any random factor. The verification tests are carried out using homogeneous fault and the fault consisting of asperity and background region. The average response spectra evaluated by the proposed method agree well with the median of the response spectra of earthquake ground motions synthesized by the ordinal waveform synthesis method.

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Even if one or a set of structural member in building structures disappears suddenly due to accidental loads, the building should stand against vertical gravity loads, dead or live. This study investigates the structural redundancy and the effects of catenary action based on another resistant mechanism after failure mechanism formation. In this paper, the ultimate resistant mechanism of framed structures is investigated experimentally and analytically. The static loading tests have been conducted. From the comparison with analytical results, the non-linear push-down analysis shows good agreements with test result. Furthermore, the limit analysis based on the upper boundary theory is proposed.

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A convex relaxation formulation for a minimum weight design problem of steel frame structures is proposed in this paper. The non-convexity of this kind of problem usually results in only local optimal solutions. Further, although the global optimal solution is not always necessary, a better local optimal solution is always preferred. To measure the accuracy of a local optimal solution, we use branch and bound approach with reformulation-linearization technique. We propose a new region partitioning technique for this approach. The effectiveness of the formulation is investigated with two numerical examples.

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A new type of mass damper is presented for passive seismic response control of spatial structures subjected to bi-directional ground motions. The mass damper consists of a three-degree-of-freedom compliant mechanism with amass, three springs and a viscous damper. By utilizing the flexibility of springs, the movement of the mass is amplified in two directions and the vibration energy of the mass is absorbed by the viscous damper. The candidate parameters of the mass damper are first searched globally using a random selection of the discretized parameter values by carrying out a series of dynamic response analyses. The parameters are further optimized using a heuristic approach called tabu search. The characteristics and the effectiveness of the mass damper are discussed in comparison to the conventional tuned mass damper that has single-degree-of-freedom.

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This jointed system using specialized screws, called large diameter bolts, is one of the moment resisting joint systems. This system is characterized by cutting an internal thread directly to wood, by threading a large diameter bolt into the wood. In this study, the tensile behavior of these large diameter bolts embedded into the wood was evaluated through various tensile tests. Bending behavior of this jointed system was evaluated through two types of bending shear tests. FEM analysis had also done to know the distribution of shear stress of wood around the large diameter bolt. Then it was made clear that tensile strength was able to be estimated from the shear strength of the wood itself and the area around the large diameter bolt. Bending strength was also able to be estimated from tensile behavior.

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The purpose of this study is to evaluate strength of glue-laminated timber beams with a circular through-hole. Pure bending tests and bending shear tests of glue-laminated timber beams with a hole were performed. The parameters of the tests were the diameter of the hole for the depth of beam. The results of these tests and finite element analyses established the evaluation method of glue-laminated timber beams with a hole. In pure bending tests, the bending strength of the beam was evaluated with section modulus and the tensile strength of the bottom range lamina in consideration of knots. In bending shear test, the bending shear strength of the beam was evaluated using the tangential stress of the hole and the tensile strength for the fiber angle of the wood. M-Q interaction curves of the beam with the hole using these evaluation methods were proposed.

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Coefficient of friction between bolt and wood was experimentally investigated. The friction was measured by a torque meter during the rotation of the bolt compressed by wood plates in the direction parallel to the grain. The testing parameters are contact geometry (conforming and non-conforming), wood species (Japanese cedar and SPF), contact pressure (three levels), and roughness of bolt surface (fine and coarse). The coefficient of static friction was influenced by the roughness of the bolt surface, but is scarcely influenced either by the contact geometry, the wood species, and the contact pressure. The friction associated with a heavy contact caused yielding in the wood, which reduced the coefficient of friction like incomplete friction.

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The new reinforced concrete structural system, referred to hinge isolated structural system (RCHIS), has been developed in order to mitigate damage of RC members. The system has the un-bond longitudinal steel bars and supplementary unanchored steel bars at the hinge region of the members. Therefore, the major damage is limited to the end of the members. Seismic tests showed their outstanding structural performance of members.
This paper discusses a reparability performance of RCHIS beams after damage. The test results prove that repaired RCHIS beams indicate almost the same deformation capacity, mitigated crack patterns and stress-transfer mechanism as the original one, and that RCHIS beams are more reparable than conventional RC beams.

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In this paper, the incremental elasto-plastic analysis method, a plastic analysis method conventionally used for the calculation of collapse load factor of frame structures, is utilized to predict the collapse load factor of truss structures. The obtained collapse load factor is then incorporated into the scheme of truss structural optimization using a Genetic Algorithm (GA) in order to generate truss structures which can not only maintain load-carrying capacity under ordinary load conditions such as dead load and live load, but also avoid collapse under accidental load conditions such as an extremely large earthquake, drastic typhoon, or other accidental loads. In the numerical example, the designed optimization scheme is implemented to solve an optimization problem of a double layer truss structure, resulting in an optimal lightweight, safe structure under both ordinary and accidental load conditions.

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The effective width theory is introduced from post-buckling strength of the uniformly compressed stiffened plates. In the ultimate strength of the plates for other load and other boundary condition, it seems that it has been given a broad interpretation of this effective width theory. The effective width is reexamined from the viewpoint of post-buckling strength. The main results are as follows.
(1) The effective width of unstiffened plates should be evaluated not by post-buckling strength by buckling strength.
(2) The effective width of stiffened plates under bending moment or shear load can be evaluated by post-buckling strength.
(3) The bending strength of the plates is calculated by the effective plastic section modulus evaluated with the effective width.

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Corrugated steel plate has high shear stiffness and a feature that it resists to in-plane buckling because of its geometric effects. Therefore, the thickness of corrugated steel plate can be smaller compared with the flat plate of the same scale. Using this corrugated steel plate as web of the girder has some advantages that such girder can save the weight of members, improve construction processes and reduce costs. With the development of corrugated web girder, this study shows the girder's basic deformation properties and buckling characteristics through experiments and numerical analysis. Finally, it is suggested in this paper that the girder collapse mode and plastic deformation capacity is evaluable by some valid indicators including buckling strength.

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This paper presents results of full-scale cyclic loading tests under constant deformation amplitude conducted to evaluate deformation capacity of welded beam-to-column connection adopted in a moment frame. Test specimens are designed and fabricated to investigate the effect of the weld access hole on deformation capacity. The relationships between ductility and cumulative plastic deformation is revealed from test results. The relationships between crack propagation at welded joint and strength of connection is evaluated regarding connection details and deformation amplitude.

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The objective of this study is to clarify the relations between the effective length and bracing stiffness of braced compression members subjected to linear varying axial force. The member is supported by one or two bracings at the center or even intervals, respectively. The buckling equations are derived by using the Rayleigh-Ritz method, and the effective lengths of columns are calculated, taking the bracing stiffness ratio κ and axial load ratio β as analytical parameters. After discussing the relations between the effective length and bracing stiffness, the required stiffness to ensure that the effective length is smaller than the unbraced length between the supporting point and the bracing point are presented.

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Structural design is usually carried out with a number of repetitive processes in which trial and error between assumptions at each stage on the structural system is done toward the selection of final solutions with an enormous effort of engineers. The authors proposed a design supporting scheme which could center their ability on the essential design processes by saving time for the selection with the use of Multi-Objective Genetic Algorithm (MOGA). In addition, through the various analyses of the steel structure models such as rigid-frame, X-type braced frame and K-type braced frame, it has been clearly shown that we can obtain other alternative design solutions with lower cost and proper drift angle in the proposed structural system. In this paper, the proposed supporting design scheme will be extended and confirmed its validity with considering not only manufacture cost in the process for making steel members and the welding cost for connecting beams and columns as well as steel cost which is considered until now in the scheme but also the penalty function which is given to the optimization problem in order to ensure the constructability of the beam-column connection for more practical use of the supporting design scheme.

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This paper reports the results of evaluation on out-of-plane vibration characteristics for unreinforcement walls of historic masonry constructions based on microtremor measurement, eigenmode analysis and proposal of estimation formula of natiral frequency. Major findings from the research are as follows: (1) In the microtremor measurement, vibration characteristics are clarified: 1^st natural frequency of walls had large aspect ratio are small, and damping factors are between 1 and 4%. (2) In the eigenmode analysis based on microtremor measurement, it is found out how masonry constructions vibrate. (3) Applying the proposed simple estimation formula, the range of 1^st natiral frequency can be found.

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The flexural strength of a beam web joint connected to a concrete filled circular steel tubular column was calculated by the mechanism method assuming plastic collapse mechanisms of column skin plate and the beam web end. The flexural strengths of the beam web joint connected to the circular CFT column and those of a beam web joint connected to the hollow circular steel tube were compared. The flexural strengths were greater when the beam was connected to the CFT column and the strengths decrease as the aspect ratio increase. The simplified formula for calculating the flexural strength of the beam web joint connected to circular CFT columns was presented.

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The elastic-plastic behavior of steel and concrete (SC) composite column encased crusiform steel and covered by thin steel tube has been investigated. Encased crusiform steel raio, material strength of steel and concrete, width-to-thickness ratio of thin steel tube and axial force ratio are thought to effect the elastic plastic behavior of SC columns. In order to evaluate quantitatively of the seismic performance of the columns, skelton curves of restoring force characteristics were investigated. The model of skelton curves was suggested to be composed of four points : flexural crack point, yield point, maximum strength point, ultimate deformation point. Effect of the above mentioned factors on skelton model of SC column was investigated quantitatively and skelton curves formulae were proposed. They were able to pursue the elastic plastic analysis and experiment results of columns.

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Realistic 3D-shake table tests using E-Defense were conducted for full-scale 5-story building specimens with/without dampers in order to evaluate seismic performance at ground motions of scales ranging from minor to catastrophic levels. The building was tested repeatedly, inserting and replacing each of 4 damper types. This paper focuses on the first test conducted with steel dampers. It discusses damper and building specimen, testing and table control methods, validations of test results, performance of the passive control scheme, and in- and out-of-plane bending of the steel dampers.

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The discusser wants the authors to answer or explain the following points:
1) The authors' discussion does not include a result of concrete specimen whose maximum curing temperature is 90°C and autogenous shrinkage attained the same amount as the specimens experienced lower maximum temperature history.
2) The proposed theory does not based on the experimental or theoretical results in some parts.
3) Several references are not suitable in the context of authors' story.

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The authors thank Assoc. Prof. Maruyama and others for their discussion and the answers are as follows.
1. The result of autogenous shrinkage with T_max =90°C concrete specimen does not occur doubt in the authors theory around 45-60°C.
2. Some reasoning is included in this study. However, authors performed an investigation, analysis inspection of physicochemical circumstantial evidence to support them and were able to suggest the issues that should be considered in future.
3. Explanations about references were added.

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Experimental and analytical achievements on the shear stiffness and strength of steel-to-timber connections tightened by high-strength bolts in the above paper are discussed about the following items. 1) The opinion that the shear resistance between steel and timber is attributed to the friction seems illogical, because the shear stiffness is not influenced by the tension reserved in the bolt. 2) The proposed formula for calculating the shear strength seems improper, because the model does not reflect the real nature of the shear resistance. 3) The data of connection, beam, and others may not be consistent, because the water content of the tested timber is not controlled in a limited range.

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The above mentioned paper deals with the ultimate strength of beam-column joint panel consist of two-directional H-shaped steel beams and R/C interior column, based on the additional theorem.
The discusser's arguments are as follows;
1) The equations (4), (31) and (35) must be incorrect according to the discusser's understanding.
2) In proposed simplified prediction method, the condition on an amount of longitudinal reinforcement of column and axial force subject to column by which the prediction method is applicable should be specified.

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The authors thank assoc. prof. Hisato Hotta for his discussion. The answers to his discussion are as follows;
1) The basic model of the inner panel with the width of the steel flange considered previously by the authors was shown in this answer. Based on this model, the meanings of the equation (4) and (35) were explained in detail. The equation (31) and (40) was corrected because of careless miss.
2) It was explained that further studies will be necessary to specify the condition on an amount of longitudinal reinforcement of column and axial force in proposed simplified prediction method.

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