This paper presents of the results of the experimental study on quality improvement of the concrete using ground granulated blast furnace slag by limestone powder. We focused on the influence of limestone powder contents on restraint drying shrinkage and strength development of concrete under several curing conditions.
As the results，the compressive strength of BLP and BLP10 (LSP 10%) are equivalent to that of BB, and that of BLP is insusceptible to demolding time compared with BB. The filling effect of LSP increased young's modulus and splitting tensile strength. The time of crack is affected by rate of decrease in mass of concrete.

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The applicability of rebound number measurement in high strength concrete with 40 to 200MPa was examined. Conclusions are as follows. (1) When compressive strength of concrete is about 50MPa to 160MPa, rebound hummer can obtain the stable measurement result. (2) The expression of relations of rebound number measurement results and core strengths of concrete columns in the concrete with 40 to 200MPa was proposed. (3) Rebound hummer cannot respond to change of concrete strength caused by the difference in aggregate. (4) The correction method of the expression of relations of rebound number measurement results and core strengths of concrete columns using cylinder specimen was proposed.

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This research aims to create the recycling evaluation system for by-product of flat glass and plaster board in consideration of the whole material flowchart that include the other field industries. Main contents are as follows:
1. Construction of material flowchart of flat glass and plaster board in consideration of the whole material flowchart that include the other field industries.
2. Estimation of the material flowchart in possibility of environmental load reduction and economical effects of stakeholder.
3. Analysis of flat glass and plaster board recycling systems by evaluation of possibility of environmental road of and economical effects of stakeholder.

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This study aims to clarify a relationship between the degradation of exterior finishing and carbonation progress of concrete. The degradations of exterior finishing of reinforced concrete multi-family dwellings were investigated from the view point of cracks of coating systems and air permeability of finished concrete. The progress of the cracks was simulated based on Markov Chain Model. On the other hand, good relations were found on the carbonation progress, air permeability of concrete and cracks of finishing. Based on these findings, authors proposed a service life of the finishing from the view point of protection of concrete against carbonation..

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We investigated the correspondence of strong ground motions and damage to houses and buildings in the 2011 Tohoku-Chiho Taiheiyo-oki earthquake. Structural damage by shaking was very small according to the investigation around strong ground motion observation sites. This was because a very short period of below 0.5 second dominated in strong ground motions, therefore, 1-2 second responses which correlated with severe damage to houses and buildings were very small. We proposed seismic intensity measure to evaluate actual structural damage more accurately by using equivalent period and damping. and simple seismic intensity measure based on the investigation.

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The P-δ effects have an influence on high rise Reinforced Concrete structures as well as high rise Steel structures. We examined influence of the P -δ effects for high rise RC structures by seismic response analysis with the 48 story lumped mass system model. The increase of a response by the P -δ effects brings increase of the strain energy and liberation energy of the P -δ effects. And, if a stability factor becomes large, these energy increases. Second, the increase rate of a response in consideration of the P -δ effects has unevenness by influence of hysteresis characteristics of RC structures. This increase rate can estimate with a stability factor and ductility factor when a response does not have influence of deflection.

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This study investigates structural responses of super high-rise residential buildings during the 2011 off the pacific coast of Tohoku earthquake based on the questionnaire survey for the residents. Final results of the questionnaire survey conducted for 22 buildings in the Kanto and the Kansai areas indicate that action difficulty and overturning ratio of furniture at the higher floors were higher than that at the lower floors, and that cracking of the concrete and the wallpaper in the room were more frequent in lower floors. Peak floor responses can be fairy reproduced by action difficulty and overturning ratio of furniture in the questionnaire survey. Cracking of the concrete and the wallpaper is closely related with maximum averaged inter-story drift angles (IDA) evaluated from the recorded motion. The IDA is also correlated with averaged pseudo velocity spectra with a period range of 1.5-3.5 s, which was highlighted in the coastal area of the Tokyo Bay, where possible crack damages were inferred in the super high-rise residential buildings.

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A method for evaluating seismic response of each story of a building utilizing signals of sensors installed on limited floors of the building is proposed, where the design model of the building is updated to a model closer to reality by applying Bayes' theorem. A fully probabilistic framework for estimation of damage probability of each component on each floor is also developed. The proposed method is applied to seismic response analysis results, which shows extremely precise evaluation ability of the method. Visualization of damage probability is also considered to be effective for decision making after earthquakes.

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An optimization method is developed for the structural and control systems of a multi-story building equipped with proportional-derivative (PD) controlled active braces. The method uses design response spectra to consider ground motions and employs the complex complete quadratic combination method to estimate the maximum response and the maximum control force. Both structural and control costs are minimized under the constraints of the maximum inter-story drift and the absolute acceleration responses. The proposed method is applied to the simultaneous optimization of a three-story building with PD-controlled active braces and it is demonstrated that the method can efficiently provide Pareto optimal solutions.

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The derivation of fundamental equations the free vibration of a spiral thin cylindrical shells is presented in this paper. Firstly, the strain-displacement relationships based on assumptions of the thin shell theory are derived and their simplified equations are proposed. Then, the principle of virtual work for the vibration of spiral thin cylindrical shells is formulated, together with some numerical results using a Rayleigh-Ritz method.
The numerical results are compared with those in the literature, and those obtained by finite element method, etc. The comparison shows the method presented in this paper is useful for analyzing free vibration of spiral thin cylindrical shells.

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Design problems with transient dynamic elasto-plastic analysis exhibit noisy and nonsmooth responses with respect to their design parameters. This leads to situations in which some derivatives may be inaccurate and/or computationally expensive to obtain, whereas others may be readily available. For such problems, derivative-free approaches seem to be more appropriate than conventional derivative-based methods because some derivatives do not exist and/or are noisy. High cost for derivative evaluation is also frequently encountered in real-world design problems. This paper presents a new optimization method which is essentially derivative-free. However, the proposed method can reflect the geometry of some smooth and inexpensive response functions. This enables enhancement of the derivative-free method by including the derivative information on some constraints. The approach can be interpreted as a practical compromise between derivative-based and derivative-free methods. Furthermore, the proposed method can also be interpreted as a meta-modeling framework, ensuring global convergence in nonsmooth optimization. The efficiency of the proposed method is studied through a numerical example of steel frame with transient analysis. The numerical result illustrates that the proposed method finds better solutions than typical derivative-based and derivative-free methods and shows reasonable convergence in all cases.

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The study deals with EP roof type lattice shells with ceiling panels supported by truss arch frames on the both sides. The estimation method based on the elasto-plastic dynamic buckling analyses considering a geometric nonlinearity is proposed to calculate practically the base-shear strength coefficient and the applied seismic lateral and vertical load distributions on the lattice shell and the truss arch frame. As far as the collapsed mechanism is concerned, the member buckling occurs in the both structural elements. The proposed method is practically useful to determine the collapse mechanism and calculate the ultimate lateral strength on the earthquake-proof design for the damage and safety limit earthquakes.

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The present paper discusses on resistance capacity of steel school gymnasiums subjected to horizontal seismic motions in the span direction. First, based on elastic-plastic dynamic response analysis for its corresponding 3-D full model composed of parallel gable frames, both of the dynamic seismic performance index _dI_S and dynamic ductility index _dF are evaluated depending on various input level. As the main parameter of the structural performance, the critical plastic rotation angles θ_p^cr appearing at beam ends on column sides of the gable frame are analyzed to quantify the effects of the rotations on _dF and _dI_S. Second, the correspondence of the direct time history analysis to pushover analysis based on a capacity spectrum method is studied in detail with respect to some adjustment factors in order that pushover analysis using the factors provide affective and accurate results. And the validity and usefulness of the proposed pushover analysis using the adjustment factors is proved as a design tool for evaluating the important seismic indexes _dF and _dI_S.

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The purpose of this study is to elucidate the behavior of wooden semi-rigid portal frames with parameters of various design conditions — span, height, vertical load, shear wall on the beam. Under proportion effects of beam depth and length, strength of the frame increases as the span becomes short. Stiffness and strength of the frame decrease as the height becomes high. If the frame have joints with shear-key, stiffness and strength of the frame with vertical load is higher than without vertical load. Yield load of the frame with shear wall on the beam is about the same as without shear wall.

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In the previous paper, the practical calculation method to predict the long-term deflection of reinforced concrete slab was proposed. In this paper, the simple method that simplified further the calculation formula of the practical calculation method was proposed to facilitate its application to practical. Based on the comparison with experimental results and calculated values in many experiments, it proved that calculated values by the simple method were almost equal to values by the practical calculation method as the degree of variety. In addition, when tolerance risk was 5%, extra factor for variation of calculated value was about 1.1 to 1.4.

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The school building suffered from a great deal of damage during the 2007 Chuetsu-Oki Earthquake. The previous study revealed that the anticipated design failure modes of most of the columns of the building were flexure although most of them actually failed in shear. In order to study the reason a parametric study was also conducted and it was concluded that the diagonal crack generated from cut off point caused shear failure in these columns. In this study static loading tests were conducted varying the length of cut off bars and the presence of spandrel walls. Main conclusions were as follows; (1)The deformation capacity of a column with cut off bars degraded tremendously on condition that the yielding hinge location was cut off point and the inclination angle of diagonal cracks generated from the cut off point was approximately 50 degree. (2)The effect of presence of spandrel walls on deformation capacities was small.

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Reinforced concrete multi-story structural walls supported on pile foundations are commonly designed assuming that they stand on solid foundation without considering their interaction. In this study, parametric studies with a two-dimensional finite element model were conducted in order to simulate their seismic-force-resisting mechanisms. The numerical model was first calibrated using the experimental data on three-story structural wall with pile foundation. The main analytical variable was the amount of upper longitudinal reinforcement in the foundation beam. Failure modes, deformation capacity and damage process of the numerical models varied depending on whether the upper longitudinal reinforcement in the foundation beam yielded in tension or not. The procedure for calculating moment acting on the foundation beams in the flexural ultimate state of the structural walls was established.

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The method to evaluate deformation at shear failure of reinforced concrete columns or beams after flexural yielding is proposed. The proposed method is based on the stress condition at the critical end of members that is the equation between force action and resistant capacity on the orthogonal cross-section of the compressive strut. The advantage of this method is simple and contains the effective factors related to the deformation capacity, shear stress ratio, axial stress ratio, shear reinforcement ratio. The statistical analysis based on previous researches shows that the method has a sufficient accuracy comparing to other method.

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The structural system with the rotational foundation can control the response of the super structure easily and has splendid merits in the viewpoint of the cost efficiency and the planning of super structure, etc. The purpose of this study is to present the response evaluation method for the buildings with the rotational foundation system due to uplift and subsidence at pile heads.
In the study, first, an influence of drawing out and subsiding of piles on an earthquake response is examined. After that, the calculation formula of equivalent damping ratio taking account of the rotational foundation due to uplift and subsidence at pile heads is induced. Lastly, the response evaluation method using the ultimate strength and equivalent damping ratio is proposed. This method is simple and show excellent agreement with time history analysis.

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Post-installed anchor is widely-spread for the seismic retrofit in existing RC and SRC buildings. Usually, anchor bars are vertically installed in a concrete surface. There are regulations diagonal angle for post-installed anchor in Japan Building Disaster Prevention Association standard. However, we think that post-installed anchor using diagonal anchor bars improves shear strength. In this research, we confirmed the shear strength of post-installed anchor using diagonal anchor bars through the structural test. The structural tests of three series are composed of the experiment on the specimen of anchor bar yield, concrete bearing failure and cone failure. From the structural tests, it was shown that if the concrete cone failure is not caused, post-installed diagonal anchor clearly improves shear strength. In addition, we proposed the evaluation method of shear strength for various failure modes. Proposed evaluation method for shear strength is in accordance with the test result well.

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Spherical graphite cast iron is not allowed to use the structural members, because its ductility is considered to be very low. On the other hand, this iron is often used to automobile parts to have high machinability and high damping, and machined specimen of spherical graphite cast iron has high ductility. This paper investigates the possibility to apply the members such as gravity columns in the structures.
In this paper, the monotonic and cyclic loading tests are performed, and the ultimate strength and plastic deformation capacity of pipe members for spherical graphite cast iron are estimated.

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When the continuously braces such as folded-roof plate can be jointed to the upper flanges of H-shaped beams, the continuously braces are expected to be effective to restrain the lateral deformation of H-shaped beams.
In this paper, the elastic lateral buckling load of H-shaped beams with continuously bracings and the required lateral and rotational rigidities of braces are developed with the energy method. Next, the elasto-plastic buckling stress is evaluated using the modified slenderness ratio with the elastic lateral buckling load for continuously braces. Finally, the relationship between the rigidity and strength of braces is clarified.

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Columns are subjected to bi-axial bending moment, since buildings behave 3-dimensionally under seismic excitations. However, only few researches on post local buckling and deterioration behavior of RHS columns under bi-directional horizontal forces have been reported. In this study, at first, a simple horizontal loading protocol was proposed based on the investigation of random horizontal displacement orbits obtained by elasto-plastic response analyses of multi-story steel frames subjected to bi-directional horizontal ground motions. After that, using the simple loading protocol, a series of tests on RHS columns subjected to bi-directional horizontal cyclic loading and constant axial force were conducted. Experimental results were compared with analytical results using multiple shear spring (MSS) model.

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An anchor-bolt-yield-type exposed column-base is typically used in low to medium-rise steel buildings. These column-base details are generally designed to consider the semi-rigid rotation spring, that caused by elastic/plastic elongation of anchor bolts. Such semirigid rotation spring stiffness (rotational rigidity) of column-base have a large effect on the seismic behavior of the building.
In this paper, the authors proposed new type of column-base, that hysteresis same to a restoring force characteristics of generally type exposed column-base. And more, the new type of column base can controlled rotational rigidity. An experimental study has been carried out on new type of column-base subjected to cyclic loadings, and the following conclusions were drawn.
1) Rotational rigidity of column base changed by the adjusting of anchor bolt length & column-base detail. 2) The proposed models of the restoring force characteristics showed good agreement with the experimental results for all specimens. 3) New type of column base having repaired performance, that anchor bolt can changed after the earthquake.

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Coupon tension tests varying with the type of structural steel and dimension of specimen were conducted in order to obtain the relation between uniform elongation and rupture elongation. Four types of steel materials (SN490B, SA440C, H-SA700B, TMCP325B) were selected and tension tests with a total of 125 specimen were carried out. Then, the characteristics of uniform elongation, rupture elongation and reduction of area were analyzed. Finally, a prediction formula for the relation between uniform elongation and rupture elongation was examined with the tension test data and a revised prediction formula was presented.

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This paper deals with load-carrying capacity and ductility of double layer latticed wall consisting of aluminum alloy truss system subjected to in-plane shear loading. Several experiments and analyses have been carried out to investigate the ultimate strength and collapse behavior of the wall, such conventional structures show brittle behaviors of member buckling and weld fracture. In order to control the fracture types of the walls, we present a new connection system based on the fuse concept to prevent brittle fracture of the whole structure. The proposed system shows good hysteresis load-deflection curve by bolt elongation of the connections.

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