Carbonation of concrete is one of the factors that determines the service life expectancy of reinforced concrete buildings. It is well known that paint exterior finishes on a reinforced concrete building suppress the concrete carbonation and prolonging service life of building.
 As exterior finishes deteriorate and the protection function against the underlying concrete decreases with the passage of time, predicting the service life of the exterior finishes is a serious issue. Degradation of the exterior finish progresses for many reasons such as the type of material, the external force of deterioration, the site to be used, the construction level, the level of maintenance and maintenance, and therefore it is difficult to predict deterioration of the exterior finish.
 Furthermore, the service life of the exterior finish is individual depending on the state of consideration of lifetime. Regarding the method of estimating the service life of the reinforced concrete exterior in “Principal guide for service life planning of buildings” edited by the Architectural Institute of Japan, the life time is defined as the condition that the coating cannot be recovered by normal repair. On the other hand, since protective performance against carbonation of reinforced concrete is required for exterior finish materials, it can also be considered that the life would be the time when the carbonation inhibiting effect becomes smaller than a certain value. However, the relationship between the deterioration of the exterior finish material and the decrease in carbonation inhibiting effect is not clear in many cases.
 In this study, authors performed field survey of existing buildings, and based on the results, proposed the deterioration prediction method of exterior materials using Markov chain model which is one of probability theory. Authors have proposed a method for evaluating the service life of exterior finish to minimize the progress of neutralization of building concrete considering the carbonation inhibiting effect of the exterior finish suppress the progress of carbonation to reinforcing bars up to the number of years required by the owner of the building.
 First, authors investigated the cracks of exterior finish painted on real buildings and predicted crack deterioration progress by using Markov chain model in Chapter 2. Next, based on previous literature showing the relationship between permeability and carbonation, authors examined the relationship between the cracks of the exterior finish and the carbonation of the concrete in Chapter 3. As a result, authors showed a possibility that there is a tentative correlation between the cracks of the overcoat layer of the exterior finish and the surface permeability. In addition, authors propose a method to evaluate the progress of carbonation from the cracks of the finish paint and the neutralization condition of concrete of real buildings. Finally, authors proposed the service life of exterior multi-layer finish to minimize the progress of carbonation of building concrete by using survey results on carbonation of actual buildings and prediction of crack deterioration in Chapter 4.

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This paper discusses the seismic performance of buildings which stories are subtracted through time history analysis. Target buildings have stories ranging from five to fourteen and are office, hotel, and residential complex. A practical evaluation method of the maximum inter-story drift is proposed for reinforced concrete buildings which stories are subtracted. Its required information is an elastic natural period of buildings, a predominant period of ground motion, and a target ductility factor. With this method, convenient required number of stories is computed so as to mitigate the maximum inter-story drift.

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 Floor response spectrum is essential for the seismic design of nonstructural components in buildings. Standardized floor response spectrum enables to evaluate seismic design forces without time history analysis. However, this approach is not often applicable to structures with a wide variety of damping ratio. This paper proposes a novel evaluation method of floor response spectra based on machine learning with neural networks. The proposed method transforms target response spectra into the corresponding floor response spectra with dynamic characteristics of buildings and nonstructural components.
 Both buildings and nonstructural components are assumed to be linear elastic. Simulated ground motions generated from a specified acceleration response spectrum are employed. Time history analysis creates floor response spectra for training data regarding various natural periods and damping ratio.
 Firstly, buildings with a single degree of freedom are assumed to design the architecture of a neural network. A simple feedforward network underestimates the dynamic amplification factor for systems with low damping ratio. For floor response spectrum in these buildings, we propose a neural network with two subnetworks. One is a network evaluating resonance characteristics. The input values to this subnet are damping ratio and natural frequency. Another is a network representing response characteristics over a wide range of natural period. The two subnetworks are joined each other before the output layer. The neural network is trained with backpropagation algorithm.
 Parametric studies investigate the adequate number of the hidden layers and the units. As a result of the investigation, the subnetwork regarding resonance characteristics should have more hidden layers compared to the other subnetwork. With the best neural network, the predicted dynamic amplification factors coincide with theoretical values in a wide variety of damping factor and natural period. The predicted floor response spectrum obtained from the neural network also has good agreement with the results from time history analysis.
 Next, the framework of the evaluation method of the floor response spectra is extended to cover multi-degree of freedom systems. This paper considers three vibration modes at most. A proper way of the modal combination is discussed regarding floor response spectra. Through the discussion, the neural network is extended to consider multiple modal responses.
 Finally, numerical examples are demonstrated for steel buildings having five or ten stories. Predicted floor response spectra have the same shape as the ground truth on any floor. The neural network infers quite instantly, and this advantage is useful to implementation of interactive software.

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 Simulation analysis is an effective method for assessing the safety of a building after an earthquake. This kind of analysis is effective for evaluating foundations or piles, whose safety cannot be confirmed by a visual check.
 During such analyses, the input motion should be set to reproduce observed waves at observed points if it exists. In the case of a single target wave the modal iterative error correction (MIEC) method can be used to set the input motion even if the analysis model exhibits nonlinear behavior. However, this method is not applicable to multi-point observed waves.
 In this study, the MIEC method was modified to be applicable to multi-point target waves. The precision of the method was confirmed experimentally.

 The findings of this study were as follows:
 (1) A new time domain inversion method was developed for multi-point records. The proposed method improves upon the method for single-point records. The proposed method increases the size of the output vector according to the number of target points. Then, the perturbation impulse matrix becomes a rectangular matrix from a square matrix. The main mode of the general inverse of this rectangular matrix is used to calculate the input correction amount. These corrections are then repeated until the error becomes sufficiently small.

 (2) The proposed method was applied to a sample problem to confirm its accuracy. An identified input motion was confirmed to reproduce target output motions at target points of the elastoplastic soil model. Moreover, using more acceleration records increased the convergence speed.

 The findings of this study confirmed that the proposed method can be applied to inversion. However, the procedure needs to be further improved because a large amount of calculation time is needed even when multi-point records are used.

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 This paper presents a new type of analytical model for an oil damper to improve the capturing accuracy of force-displacement relationship due to the small excitation such as the vertical seismic response. The structural design of buildings have been required the performance specification, and its specification has been major diversification. The building employed the three-dimensional isolation system was designed and constructed to ensure the isolation performance in the vertical direction as well as the horizontal direction. The concept of a three-dimensional isolation system for a reactor building has been proposed by the authors to ensure the structural integrity for a large reactor vessel. This three-dimensional isolation system, which consist of thick rubber bearings, disc springs and vertical oil dampers, has the horizontal natural period of 3.4 s and the vertical natural period of 0.33 s. According to the Maxwell model, the damping force is reduced as reducing the natural period (high-frequency) for the input wave. To realize the proposed three-dimensional isolation system, it is required to clarify the damping force characteristics of the vertical oil dampers because the vertical oil dampers are employed under the higher frequency (0.33 s) compared to the conventional vibration controlled buildings with oil dampers.
 The purposes of this paper are divided into three main groups. The first is to clarify the damping characteristic of the full scale of vertical oil damper for both the linear type and the bilinear type, which has the maximum damping force of 2000 kN at 25 cm/s, through conducting the excitation tests which include the small amplitude with the high frequency and the seismic response excitation. The second is to investigate the variation of damping force due to the increasing temperature of the vertical oil dampers by conducting the sinusoidal excitation tests. The third is to create a new analytical model applying to the time history response analysis, which is focused on both the increasing temperature phenomena and the damping force characteristic in the small excitation such as the vertical seismic response displacement.
 The primary results are summarized as follows:
 1) The stable force-displacement relationships were obtained against the excitation waves with the small amplitudes and the high-frequency up to 5.0 Hz by ensuring higher stiffness of the vertical oil damper.
 2) The reducing ratio for the damping coefficient up to the allowable temperature (80°C) was revealed to be approximately 7%. The increasing temperature due to the seismic response excitations were clarified to be from 2°C to 4°C. This result means that the decreasing damping force has little impact on the seismic response.
 3) The new type of analytical model consisting of the double dashpot elements and the single stiffness element, which is referred to as the D.D.P model, was proposed to improve the force-displacement relationships in small excitation that results in the orifice characteristic. The analytical results obtained by the D.D.P model correspond to the test results not only for the small excitations but also the large excitations. These results demonstrate that D.D.P model can calculate the force-displacement relationships, which have the orifice characteristic, are closer to the measured value than to the ordinary Maxwell model. Additionally, the D.D.P model can accurately simulate the force-displacement relationships considering the reducing forces in response to the increasing temperature by using the increasing temperature model.

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 In steel roof gymnasiums with RC substructures, out-of-plane response of Cantilevered RC walls are predominant during seismic responses, which triggers sequential damages of structural or non-structural components. Particularly, in 2016 Kumamoto earthquake, structural damages related to space frames (i.e. member buckling, member local buckling, post-buckling ductile fracture and connection bolt fracture) were reported, which is the newly observed damage characteristic. Space frames are generally elastically designed, thus it is important issue to make clear the damage process for the aseismic design, which is the main purpose of this paper. The chapter 2 presents the detail of the damaged gymnasiums (Gym. A and Gym. B), the numerical modeling, the observed seismic inputs. The chapter 3 and chapter 4 present the seismic damage evaluations of Gym. A and Gym. B, respectively. The numerical simulation results were analyzed by the comparison with the observed damages. The chapter 4 presents the applicability of static estimation method proposed by the AIJ design recommendation.
 In summary, the following results were obtained:
 1) In Gym. A, out-of-plane response of the cantilevered RC walls along the transvers direction were main reason causing the roof damages. After the collisions between the anchor bolts and the slotted hole ends during the main shock, the upper chords and diagonals connected to these bearings are forced to be bucked. Following the buckling behavior of these member, the load path is considered to shift from the transvers direction to the longitudinal direction, which triggered the load increasing of the lower chords along the longitudinal direction and the subsequent connection bolt fracture.
 2) In Gym. B, out-of-plane response of cantilevered RC walls along the longitudinal direction and the asymmetrical. 1 wave mode of the roof along the transvers direction were main reason causing the roof damages. The lower chords connected to the roof bearings along the longitudinal direction are forced to be buckled by the reaction force of the cantilevered RC walls during the former shock. The lower chords connected to the roof bearings in the transverse direction are forced to be buckled by the roof response itself during the main shock. Considering the actual damage, it is assumed that the actual ground motion level could be less than the input seismic waves.
 3) Vertical collapse displacement may be dependent on the stability and load capacity of the upper compression chords along the transverse direction. Based on the results, the roof damage of Gym. B was more moderate than that of Gym. A because the main direction of the seismic responses of Gym. B was not the transverse direction. On the other hand, the vertical collapse displacement is less than the actual situation. It is assumed that the non-structural members, which is not considered in this numerical simulation, could affect on this difference.
 4) Static analysis considering the combination load of the roof response used in the AIJ design recommendation and bearing forces by cantilevered RC responses generally captured the observed damaged roof members. This relatively simple method can be used for screening the expected damages in these kind of space frame roof gymnasiums.

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 This paper presents a numerical computation procedure to solve the minimal surface problem based on discrete differential form. Since membrane structures possess structural stiffness by introducing prestress, an initial form is needed to be stable after introducing appropriate tension stress. Therefore, a form-finding for membrane structures is required to decide the initial form. The form-finding is classified into methods based on mechanical description and geometric description. The former methods are the analysis of an equilibrium form with uniform tension stress distribution in a membrane. The latter methods are variational problems to find a form of minimal area with a boundary, making use of the property that the uniform stress surface is equal to the minimal surface. However, It is well known that the numerical computation procedure is unstable in convergence process when three-dimensional coordinate values are set as unkown variables in the minimal surface problem. It is necessary to know the reason of unstability in a computational procedure.
 In this paper, we formalize the form-finding analysis based on discrete differential form which provides the simple formulation for cable-reinforced membrane structures in Chapter 3 by Ref. 9). As a result, it reveals that the coefficient matrix of linearized equations for convergence corresponds with the geometrical stiffness matrix as shown in Ref. 10). Numerical results of discrete minimal surface with fixed boundary and with free boundary constraint by cables in Fig. 6-8. These results agree very well with the previous research of minimal surface problem. Next, we compare with the present method and the initial stress method focused on a geometrical stiffness matrix. This result shows that the present method corresponds with the initial stress method without material property and the nonlinear term of strain-displacement matrix in calculating unbalance force affects also the result as shown in Fig. 9.
 Finally, we confirm that obtained solutions possess the uniform stress distribution on discrete surfaces by using the geometrically nonlinear analysis by finite element method. In the case of the model with fixed boundary, exact uniform stress distribution is obtained as shown in Table2. In the case of the model with free boundary constraint with cables, the slight error can be found around the central part of cables. However, these results approximate the minimal surface very well, it is verified that present method is useful for the form-finding of membrane structures and cable-reinforced membrane structures. In future, we develop the form-finding analysis with good convergence procedure.

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 Construction of wooden buildings utilizing CLT has become active in Japan. Although a design manual for CLT buildings was published in 2016, it does not cover a connection using drift pins and insert-steel gusset plate which are one of the frequently used connection types. Nakashima et al. showed that the performance of the connection could be simulated by conducting nonlinear analysis of rigid-body-spring model representing a drift pin on CLT. However, simple formulae to calculate shear stiffness and shear strength of the connection is required in practical design. In this paper, the connection with different strength grade and layer constitution of CLT were tested. In addition, the effect of the location of un-bonded edge-jointing, grain direction and the number of drift pins and their layout were also discussed. Finally, calculation formulae of shear stiffness and shear strength of the connection were proposed.
 Chapter2 introduces the connection tests and the test results. A steel plate was inserted into CLT and they were jointed with drift pins. The connection was subjected to static monotonic loading. Parameters of specimens were strength grade and layer constitution of CLT, the location of un-bonded edge-jointing, grain direction and the number of drift pins and their layout. Total forty types were tested, each of which had six specimens. The variability of the shear stiffness was large while the one of the shear strength was small. The effect of the location of un-bonded edge-jointing on the shear stiffness and the shear strength was not significant. 3-layer 3-ply specimens using two drift pins tended to fracture by split failure between the two drift pins as compared with 5-layer 5-ply specimens. In addition, the shear stiffness and the shear strength of some specimens having two drift pins did not reach twice of the ones having one drift pin. It was more significant in the shear stiffness, and the corresponding coefficient of variations were also increased.
 Chapter3 introduces evaluation of shear stiffness of the connection based on theory of a beam on elastic foundation. In order to obtain the strict solution, different deflection curves have to be defined at each lamina and they are combined based on the boundary conditions because the foundation constants are different at each lamina. Therefore simplified mechanical model are proposed, which gives practical formula of shear stiffness, instead of solving complicated strict model.
 Chapter4 introduces evaluation of shear strength of the connection based on European yield theory. Since a lot of yield modes can be assumed, the candidates of the yield modes are reduced by considering possible range of parameters and the corresponding formula is simplified.
 Chapter5 introduces comparison between test results and calculation results. Yield strength and ultimate strength were evaluated by Nakashima's method as well as by proposed method. The proposed method could predict test results with good accuracy.

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 In Chapter 1, the background and purpose of the research and outline of the study will be described.
 The purpose of this research is to evaluate the bending performance of Glued Build-up Member (GBM). When comparing the Timber used in GBM and the lamina of Glulam, the lamina is as small as 20 to 50 mm while the lamina in the cross section direction is 105 to 180 mm in timber, and the timber used in this GBM is the point that the pith necessarily exists near the center of the cross section, the sawn timber is higher than the lamina, the distribution of the moisture content is not uniform within the lumber cross section. The influence of these features on the bending performance of GBM is not clear. In order to investigate these effects, in this paper, a bending test of a full scale GBM test specimen in which 120-150 mm square cedar timber was adhered with 2, 3, 4, 5 epoxy adhesive was carried out.
 In Chapter 2, explains the test specimen, the method of experiment and the experimental results.
 Cedar timber from Kumamoto prefecture, which conforms to the machine grade E70, E90, E110 of Japan Agricultural Standards and has a water content of 18% or less, was used as the test specimen. Production of test specimens was conducted according to the manufacturing method prescribed for this GBM, by selection of sawn timber, application of adhesive, clamping, curing, finishing processing. The specimen size is determined for each timber size and number of layers, the shear span a is 4.5H or more (H: GBM cross section height) so as to cause bending failure, the test specimen total length L is 9 m or less from the experimental dimension, The number of specimens was set to 5 or more for each sawmill. The experimental method is a two-point loading bending test, and the supporting point is the both-end pin support. We classify the failure types of specimens into five types of A, B1, B2, C and S based on load-center deflection relationship.
 In Chapter 3, evaluation of experiment results will be described.
 When a bending stress and bending stiffness are calculated with a uniform cross section model for each number of layers, the 5% lowest value of the bending stress is smaller than the bending strength. Moreover, the experimental value and the estimated value were about the same as the 50% lowest value of the bending stiffness. When evaluating bending stress and bending stiffness using a GBM cross section model considering the difference in elastic bending modulus of each timber, the values of bending stress and bending stiffness are both smaller than the variation of the uniform cross section model. Also, the bending stress is close to the estimated value of the strength. Therefore, it is considered that evaluation of bending performance using GBM cross section model is effective.
 Using the GBM cross-section model, if the stress level of the lowermost timber is evaluated by the combination stress of the bending component and the tensile component, the combination stress becomes larger than the strength as a whole. This is considered to be due to the fact that many safety factors are expected for the tensile strength.
 In Chapter 4, presents a summary of this paper.

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 Traditional-type boarding floor diaphragm of wooden structures consists of narrow boards fastened by nails and has low shear stiffness unlike plywood sheathing floor diaphragm. It is incapable of achieving so-called rigid floor assumption which is generally assumed in the current seismic design standard. In practical design and seismic diagnosis, when the structure has flexible floor diaphragm, three dimensional framing analysis is required. Therefore, the flexible floor diaphragm is believed to make the dynamic behavior quite complicated and to make the simulation difficult.
 In this paper, simplified evaluation method of basic dynamic properties such as natural circular frequency and mode shape for single-story wooden structures is proposed. A theory of 2x2-span flexible floor dynamics model which the authors has proposed is developed, and useful indexes indicating the effect on the dynamic properties are derived in the process. Although eigen value analysis requires matrix operation and numerical solver to obtain natural circular frequency and mode shape, the proposed method can provide them only with the four arithmetic operations of the indexes. The accuracy of the method is confirmed by comparison with numerical analysis solutions. In addition, applicability of conventional method such as sparsely discretized model (i.e. lumped mass model) and static pushover analysis is also investigated.
 The followings are findings of this research.
 1) Dynamic properties such as natural circular frequency and mode shape were estimated using the ones of simplified models with smaller number of degrees of freedom: reverse symmetric shear model and symmetric shear model. Regarding mode shape, another model might be included, and the accuracy was improved in particular cases.
 2) Dynamic properties of the simplified models stated above could be calculated using a controlling index.
 3) Lumped mass model was likely to give smaller natural circular frequency compared to strict solutions due to neglect of flexural stiffness of floor diaphragm and to sparsely discretized mass.
 4) Accuracy of static analysis for natural circular frequency(i.e. initial stiffness) was variable. Mode shape was well predicted except for particular cases.
 5) Natural circular frequency and mode shape of whole structure could be determined by the two controlling indexes, and the contours were drawn. If the criteria of dynamic properties are set, the acceptable range of the two indexes is clearly found out from the contours.
 By considering mode shape given by the proposed method as acceleration distribution, it can be applied to static force distribution in horizontal direction when static push-over analysis is conducted. As a future plan, two-story structures and inelastic behavior derived from plasticity of shear walls will be addressed.

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 In reinforced concrete buildings with soft-first-stories, sections of columns in the first-stories are usually enlarged from those of the second-story columns to prevent story collapse at the first stories. Test results (Ref. 4) show the strength and stiffness of this type of frames are lower than the expected values by assuming flexural failure at the top of the first-story column. These lacks are due to the damages on the beam-column joint at the top of the first-story column. In this paper, a method for calculating the strength of the beam-column joints is proposed focusing the cases that columns extended outside the building and the joints are subjected closing loads. The method is based on the failure mechanism observed in the tests and able to consider anchorage failure of beam top bars.
 Two failure modes named the column failure mode and the beam failure mode are considered for a beam-column joint. The column failure mode is the flexural failure of the first-story column at the beam bottom face. The moment capacity for the column failure mode is calculated by flexural analysis assuming the whole cross-section of the first-story column is effective (Fig. 6b). The beam failure mode is the flexural failure at the inclined section connecting the two reentrant corners of the beam-column joint (Fig. 7). The moment capacity for the beam failure mode is calculated from the moment equilibrium between external forces and resultant forces at the section (Eq. 5). Anchorage failure by the local crushing of the concrete should be considered in determining the forces in the beam top bars in the calculation while yielding is assumed for the column bars and the lateral reinforcement in the joint.
 The local failure of concrete is assumed to occur when the compressive stress of concrete inside the bend of the anchored bars (f_b) reaches the compressive strength of concrete (f_c). The bearing force acts inwards in the radial direction against the tensile forces of the top beam reinforcement and the first-story column reinforcement (Fig. 9). The compressive stress f_b is derived by dividing the bearing force by the area determined by the product of the width of the first-story column and the width of the strut. For the case that the reinforcements are arranged in multi-layer, the sum of the compressive stress of concrete at each layer is treated as f_b.
 The strengths calculated by the proposed method agree with the test results at a rate of 1.05 to 1.23 and evaluate the observed failure modes appropriately (Fig. 17).
 In addition to the method to evaluate the strength of beam-column joints, a design process to prevent the anchorage failure is also proposed. In the design process (Fig. 19), it is examined that the compressive stress of concrete inside the bend of bars at that the tensile forces of the bars reach yield strengths is lower than the compressive strength of concrete.

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 Damage controlling performance has been becoming an important issue for recent structural design to achieve a good business continuity plan based on lessons obtained from Kobe, Tohoku and Kumamoto earthquakes. Society seeks for good seismic damage reduction ability in buildings, which may be seen in the base isolated buildings. Another structural system to realize damage reduction ability for reinforced concrete buildings is unbonded post-tensioned precast concrete system (hereafter, rocking system). The rocking system has high seismic damage reduction ability, but the seismic response drift tends to be larger due to insufficient energy dissipation ability. This paper demonstrates structural performance of rocking walls with energy dissipating elements from experiment, accuracy of analytical procedure of Guidelines for Structural Design and Construction of Prestressed Concrete Buildings Based on Performance Evaluation Concept (hereafter, the 2015 AIJ draft guidelines) to compute ultimate flexural capacity, and accuracy of the multi-spring model to obtain envelop curve and hysteresis loops of lateral load － drift relation.

 Firstly, seismic damage reduction ability of four rocking walls with energy dissipating elements was investigated by comparing their performance with that of a reinforced concrete wall and a rocking wall without energy dissipating elements. Four rocking walls, tested in Tokyo Institute of technology in 2016, were 1800mm tall with cross section of 200 x 450mm. Test parameters were cross section dimension of energy dissipating elements and presence of steel fiber. The test was carried out under cyclic static lateral loading with constant axial load. Four rocking walls with energy dissipating elements showed flag-shaped hysteresis loops with small residual deformation and large energy dissipation. Damage concentrated on the edge of walls as that for the rocking wall without energy dissipating elements. Residual drift angle was less than 0.25%, which is the reparability limit state I in the 2015 AIJ draft guidelines, until 2.0% of drift angle. Equivalent damping ratio was approximately constant of 10% until 2.0% of drift angle.

 Secondly, the ultimate flexural capacity was well simulated with the equation based on the 2015 AIJ draft guidelines considering with the effect of energy dissipating capacity. The multi-spring model also simulated the ultimate flexural capacity and hysteresis loop with good accuracy in terms of backbone curve and residual deformation.

 The experimental and numerical results showed superior seismic damage reduction ability of rocking walls with energy dissipating elements.

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