In the prediction of roof snow loads on buildings, unbalanced snow distribution due to wind flow on roofs is a problem. Although some experimental research has been carried out using wind and water tunnels, till date, only a few attempts have been made to apply computational fluid dynamics (CFD) to this issue. In this study, a method based on CFD was applied to the prediction of roof snow depth for an isolated gable-roof building. By comparing the results with data from observations, the accuracy of prediction using CFD simulations was investigated.
 An isolated gable-roof building, with the height of the eaves H_e = 6 m and width W = 6.6 m, was considered (Fig. 1). It was placed such that it was perpendicular to the approaching wind flow. The model could be given one of three different roof pitches, specifically, 3:10 (=16.7°), 5:10 (=26.6°), and 7.5:10 (=36.9°). ANSYS Fluent 14.5 commercial software was used to perform the steady-RANS (Reynolds-averaged Navier-Stokes equations model) computations based on a control volume approach for solving the flow equations. The computational grid consisted of 2,355,280 cells for the domain for the 5:10 roof pitch case (the other roof pitches had similar number of grids). Special care was taken to allocate an adequate number of hexahedral cells along the oblique roof so as to avoid the tetrahedral and pyramid cells. The computational conditions used in this study were set based on the guidelines of the Architectural Institute of Japan. The realizable k-ε model was used as the turbulence model. The snowdrift model proposed by the authors was implemented in the CFD code as the User Defined Function. For modeling suspension, the transport equation of snowdrift density Φ was solved.
 Figs. 5-7 compare the mean streamwise velocity U₁, turbulent kinetic energy k and the pressure coefficient obtained by CFD with the measured values obtained by the wind tunnel experiment for the all roof pitches. The agreement between the results of the CFD analyses and those obtained by the experiment is generally good. The model parameters appeared in the snowdrift model were examined by the sensitive analysis on the predicted snow accumulation as shown in Figs. 8 and 9. Figs. 12 and 13 shows the normalized snow depth with different wind velocities. The well-known tendency that snow is eroded on the windward side and accumulates on the downwind side was reproduced. Furthermore, the drift coefficient C_d obtained by the CFD result was compared with the observational results, as shown in Fig. 14. The observational data consisted of approximately 1,300 examples of snowdrift formation on gable roofs in Norway, which are also the basis of the model equation in ISO 4355. The CFD result obtained with U_ave = 2.0 m/s and U_H = 2.0 m/s is very close to the observational data and the model.
 It was confirmed that the observational data can generally be reproduced by the proposed CFD simulation. The prediction accuracy for different roof geometries will be examined in future studies.

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 The Tohoku earthquake of magnitude 9.0 occurred on March 11, 2011. As a result, the need for Structural Health Monitoring (SHM) was highlighted. To assess the health of buildings, modal parameters such as natural frequencies and damping ratios are the basic and important damage indicators. In addition, maximum inter-story drift angle is also recognized as an important indicator. If we have to estimate these indicators very precisely, we need to install accelerometers on all floors. However, it is not realistic due to the cost. In many methods to estimate the response using small number of accelerometers, the excitation (input) is assumed to be available. However, in some cases, some sensors including the input sensor may not be available. Thus, in this paper, we propose two methods for the estimating inter-story drift angle using small number of accelerometers without knowing input information.
 The proposed methods (method 1 and method 2) are based on two assumptions. One is that the response is represented by the superposition of the response of only lower modes. The other is that mode vectors and participation factors are available from the structural design model.
 Based on the assumption, for the method 1, first, we estimate modal frequencies and damping ratios using the subspace method from obtained acceleration data. Second, we decompose observed acceleration data to each mode by solving simultaneous equations using pseudo-inverse matrix. Third, we calculate mode response by focusing on the vibration equation of each mode. On the other hand, for the method 2, we directly calculate the mode response by just solving simultaneous equations. It was verified that these methods could successfully estimate the modal response as well as the inter-story drift angles.

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 Recently, Inertia Mass Dampers have been developed and realized. The damper can exert negative stiffness with neither energy supply from outside nor complicated electronic control devices. It is possible for the damper to exert inertia mass much greater than physical mass. In practical applications to controlling relatively large structures, great mass would be required inertia mass. But in the case of controlling small structures, smaller inertia force yielded by flowing fluid would be enough.
 In this paper, we propose a Linked Fluid Inertia Mass Damper (LFIMD) which is effective to reduce seismic response of low-rise structure. The damper is composed of two cylinders, two piston rods and two link tubes that connect two oil chambers of each cylinder. There is no orifice in the piston and the fluid runs in the tube at high velocity when piston rod moves back and forth. The ratio of two piston displacements can be adjusted based on the ratio of cross section area of two oil chambers linked with a tube. The damper works in three ways. They are viscous damping effect by flowing fluid, negative stiffness by inertia mass effect with moving fluid at high velocity in the tube and the displacement control by hydraulic link mechanism. The damper is quite effective in reducing acceleration response, because load-displacement relationship of the damper has negative stiffness by inertia force, decreasing the maximum shear force of a total structure. The LFIMD yields negative stiffness by means of simple passive mechanism. It can prevent damage concentration to a specific part of a multi-story building, as well as the torsional vibration of a building with stiffness or strength eccentricity.
 In the first part of the paper, we propose seismic response control method with LFIMD and show its dynamic mechanical properties by performance test on a LFIMD. Important findings are; there exists constant internal friction force between the cylinder and the piston, the damping force depends on the squared piston velocity, inertia force depends on frequency and linking force depends on the compression stiffness of the fluid and rigidity of the tube. It was confirmed that the test results conclude with simulated results fairly well.
 We perform seismic response analysis of a wooden house with LFIMDs. It is shown that LFIMD is capable of exerting seismic response control in multiple ways. In the case of no damper, the deformation and absorbed energy are concentrated to either of the story. On the other hand, in the case of using LFIMDs, it is possible to make structural deflection distribution uniform and to reduce the maximum deformation with link mechanism. Maximum acceleration is reduced due to negative stiffness by inertia force. Finally, we confirmed the use of LFIMD is quite effective in reducing seismic response of low to mid rise building structure.

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 Durability or weather resistance is one of the biggest concerns about isolation rubber bearings. Since rubber material is thought to be less durable than other structural materials such as concrete and steel, several investigations about the durability of rubber materials actually used for structural members of bridges and buildings for several decades to one century have been conducted. Those results show that mechanical properties of surface part of the rubber materials have been changed to a certain degree, by being exposed to some degradation factors such as oxygen, ozone, ultraviolet rays and water, and those of inner part are assumed to keep almost the same as those in the initial condition. Hence, covering rubber or surface rubber has an important role for rubber bearings to keep their properties less changed for an expected long life span.
 In this paper, aging effects of oxygen, water / saltwater and the combination of oxygen and water / saltwater on chemical properties of two types of covering rubbers actually used for rubber bearings were experimentally studied. Rubber A (natural rubber, NR) and Rubber B (complex of NR and Ethylene-Propylene-Diene terpolymer, EPDM) were selected for test materials. Accelerated aging test corresponding to 80 years, water / saltwater cyclic spray test for 30 / 60 days, and the serial testing of the above two tests were conducted for the both rubber materials. Considering the configuration of rubber bearings and the environmental condition of isolation levels, it is evident that degradation factors affect only in one direction from the surface to the inside of rubber bearings. Therefore, rubber blocks, not thin pieces such as dumbbell specimens, were chosen and exposed to the above degradation factors. After the degradation, rubber blocks were sliced and cut into small specimens, disposing the peripheral part and the back side, to remove the degradation effects from the side and the back of the rubber blocks. Finally, some chemical properties, such as chlorine penetration depth, chemical constitution, crosslinking density, glass transition temperature and antioxidant quantity, were evaluated for each degraded specimens, and compared to the initial values.
 Test results showed that oxidative degradation affected the chemical properties of the both materials much greater than water / saltwater degradation. Also it became clear that oxidative degradation had a complicated effect on the changes in the chemical constitution of Rubber A, due to the counterbalance of the depolymerization characteristics of NR and the lasting vulcanization, while Rubber B simply became harder and denser with the progress of oxidation, due to the synergistic effect of the cross linking characteristics of EPDM and the lasting vulcanization. Although antioxidants contained in the both rubber materials were apparently decreased by the consumption and the leakage, some sufficient amount were still remained even after the oxidative degradation corresponding to 80 years. Thus, it might be concluded that covering rubbers were able to protect rubber bearings from degradation factors such as oxygen and water / saltwater for an expected life span of isolation buildings.

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 For seismic design for embedded large structure, evaluation of soil-structure interaction is very important. However, the effect that embedded side soil gives structure uplift behavior is not clear.
 In this paper, uplift constraint mechanism of side soil is examined. And, new modeling method for seismic response analysis of embedded structure is proposed. First, to confirm the accuracy of embedded SR model considering side rocking spring, seismic response analysis of reactor building is conducted by soil FE model and traditional embedded SR model. Then, by static uplift analysis of rigid foundation, it is clear the difference between both models in uplift behavior. And then, considering this difference, a new modeling method is proposed. The validity of this proposed method is confirmed by static and dynamic analysis by comparing from result of FE model.

 The Results obtained from this study are summarized as follows.
 (1) In embedded SR model with Novak side soil spring, by considering rocking side soil spring, the building response result of analysis comes to match that of soil FE model. And at the point of view of uplift behavior evaluation, embedded SR model with Novak rocking side soil spring make safe side evaluation, when the result of soil FE model is assumed to be true.

 (2) There are two reasons why there is the difference between the uplift evaluation between embedded SR model with Novak horizontal and rocking spring and soil FE model. One is that interaction of soil stiffness between the side soil stiffness and bottom soil is not considered. The other is that vertical constraint effect of side soil is not considered. By considering these effects, the result of embedded SR model comes to match that of soil FE model.

 (3) The proposed embedded SR model makes safe side evaluation of uplift behavior when the result of soil FE model is assumed to be true.

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 There are many examples of application of TMD. A high-rise building and a floor slab with large span in architecture field, a cable stayed bridge and a suspension bridge in civil engineering, for example. The response reduction effects by those examples are verified. TMD is fit for the vibration control of spatial structure because it is possible to install TMDs by a single supporting point. Therefore there are many studies on the vibration control for spatial structures. The vibration controls for arch structures are examined by Kato and Yamada for example. Those for dome structures are investigated by Yamada and Yoshinaka. However, the practical examples for spatial structures can not be found. There is still much left to be studied hereafter about the vibration control of spatial structures by using TMDs in practice. This paper is intended as an investigation of vibration control effects by plural TMDs of cylindrical lattice shell roofs with TMDs by numerical vibration analyses.
 First, the effects of the number of installed TMDs and location on response reduction effects are examined. In addition, the effects of differences of period and phase characteristics of input earthquake motions on response reduction effects are investigated. Finally, the response estimation by the parallel multi-mass system substituted for arch structure with TMDs is attempted.
 From the numerical results, it is concluded as follows.
 1) By installing a plurality of TMDs which target a single mode for plural modes, the responses of shell roof are reduced with wide periodic band.
 2) By installing the plural TMDs spatially distributed on antinodes of target modes for control, the responses of cylindrical lattice shell roofs are reduced evenly regardless of period and phase characteristics of input earthquake motions.
 3) Each TMD of plural TMDs has different frequency ratios, therefore there are cases where the responses of mode with the period which is close to the period of target mode are also reduced.
 4) The effects of distribution of Quadruple TMD which is installed four TMDs on the antinodes of mode on response reduction effects are small. The responses in the vicinity of the period of target mode for control reduce uniformly regardless of the distribution of TMDs.
 5) The vibration control effect is more sensitive to the differences of the period characteristics than to the differences of phase characteristics of input earthquake motions.
 6) The response reductions of cylindrical lattice shell roofs installed TMDs agree with the energy absorption of TMDs.
 7) The response reduction factors of cylindrical lattice shell roofs by installing the TMDs can be estimated by the energy absorption factors for parallel multi-mass systems.

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 It is important to evaluate that the existing strength of wooden construction has maintained enough strength performance experiencing a long time for using long term safely. Therefore, it is necessary to understand the survival strength of structural members and joints damaged by biodeterioration in the wooden houses and building. But there is very limited database covering the survival strength of damaged materials in relation to the measurements from diagnostic tools. Many wooden constructions have been damaged by subterranean termites. The aim of this study was to investigate the relationship between the survival strength of single shear of a wood screwed joint damaged by termites and biodeterioration measurements made from the diagnostic tools. In addition, it was proposed the estimating method of a survival strength of wood screwed joint using the penetration depth that is a biodeterioration measurement value.
 In this study, a test specimen made of Todomatsu (Abies Sachalinensis) and Norway spruce (Picea abies). The wood screw is 45 mm in total length, 40 mm in screw length, and 5.4 mm in outside diameter. The steel plate is 3.2 mm in thickness and has a hole of 6.0 mm in diameter. The damaged specimens were carried out in pine forest close to the sea in Kagoshima and Wakayama. The diagnostic tools were used from measuring the penetration depth is called Pilodyn® and the ultrasonic propagation velocity is called Dr.Wood. The both of measurement positions are closed to the joint part.
 As a result, the specimens shows the four failure modes, which included the fracture of wood screw head, embedded failure of wood, splitting failure of wood, and shear failure of wood. The yield strength was decreasing accordance with the increase in the penetration depth or decrease in the ultrasonic propagation velocity. It was found that there was a good correlation between the survival strength and the penetration depth.
 The survival strength was estimated by a small damaged part and a damaged part using the penetration depth. The estimated strength was calculated by the EYT and the improved EYT for CLT by Uible. The damaged part was separated by subtracting the penetration depth measured from the sound penetration. The damaged part was assumed to be the strength was lose, and the small damaged part was assumed to have the same strength as the sound part. As a result of estimating, the estimated values indicate the good correlation with the experimental values. In addition, it was estimated by the material strength exchanged to AIJ standard from the experimental value in the same way for using generally. As a result, it was shown the good correlation between the experimental strength and the estimated value by using the boundary value obtained in the experimental values.

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 In the precast prestressed concrete frame assembled by post-tensioning unbonded tendons with ungrouted sheaths, called an unbonded PCaPC frame, the beam rotates against the column face as a rigid body, causing remarkable opening at a connecting interface between a precast concrete column and a beam with scarce residual deformation. This can be achieved by the post-tensioning unbonded tendon, since its tensile strain is kept constant over the whole length. The unbonded PCaPC frame is designed as a strong column-weak beam system, so an accurate and simplified evaluation method for the ultimate flexural strength and deformation of the beam is necessary to mitigate earthquake damage. Attempts to estimate these values were carried out in previous studies. However, most studies dealt with an isolated beam removed from a moment-resisting frame, which cannot well reflect the precise seismic behavior of actual frames. In addition, they also requires a complicated mathematical calculation.
 In this study, therefore, a macro-model, which can reproduce the flexural behavior of the cruciform unbonded PCaPC subassemblage, is proposed to evaluate the ultimate flexural strength and deflection of the beam, whose unbonded tendons are placed symmetrically at the top and the bottom. An accurate and simplified estimation method for the ultimate flexural strength and deflection is then proposed based on the macro-model. These values predicted by the method are finally compared with previous experimental results to verify its validity. The proposed macro-model and general findings taken from this study can be summarized as follows.

 (1) In the macro-model, after an opening occurs at the beam-column interface due to bending moment, the beam rotates as a rigid body. Beam axial deformation resulting from compressive strain, which develops at the extreme compression fiber along the entire length of the beam, is supposed to concentrate on the beam end. Concrete on the compressive side of a beam is shortened at a tendon position, and the opening at the beam-column interface contributes primarily to elongation of the beam at a tendon position on the tensile side.

 (2) The evaluation formula for the ultimate flexural strength and deflection of a beam was proposed based on the plane section assumption at the beam end and the following conditions; the sum of axial deformation attributed to both the concrete shortening and the opening distance at the beam-column interface at the tendon position in a cruciform subassemblage is equal to the total elongation of the tendon, and the tensile and compressive resultant force in a beam section is the same.

 (3) In the evaluation formula, the distance from extreme compression fiber to neutral axis in a beam section at the beam flexural strength, defined as x_n, is a crucial factor to calculate the beam strength and deflection. To obtain x_n, therefore, both an iterative method and a simplified manner were introduced.

 (4) Predicted ultimate flexural strength and deflection of a beam by the proposed method showed a good agreement with the previous experimental results. The discrepancy between the calculated and observed ultimate flexural strength remained in a range of ±10%, and that of the ultimate beam deflection remained within ±15%.

 (5) Since the distance x_n, obtained from the simplified manner aforementioned, tended to be slightly greater than that from the iterative method, the ultimate flexural strength and deflection of a beam by the simplified manner were found to be somewhat smaller than those by the iterative method. However, their discrepancy remained in a range of ±5% for both the ultimate flexural strength and deflection when the prestressing ratio of a tendon to its yield strength is greater than 0.6, which is generally accepted in an actual construction.

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 When a pin-ended buckling restrained brace is subjected to axial compressive force, the rotation of the joint is involved by local deformation at the end of the buckling restrained member (called as local deformation at the end) and affects the condition to prevent global buckling. In the previous research 5), the method to calculate deflection of the core member and bending moment of the buckling restraining member considering local deformation at the end were presented. Moreover, conditions of global buckling were proposed and the validity was verified by cyclic loading tests and finite element analysis. However, the method to estimate local deformation at the end of the buckling restraining member remains as a problem to be solved.
 In this paper, the method to calculate local deformation at the end is proposed for a pin-ended tube-in-tube brace shown in Fig. 2. The validity of the proposed method is verified by loading tests and finite element analysis.
 In Chapter 2, as shown in Fig. 4, a mechanical model called as an end part model, which focuses on the end of tube-in-tube brace is proposed. In this model, the round bar located at the bottom of the rigid member simulates plastic rotation of the yielded core member. The restraining member is subjected to stiffening force B by applying horizontal force Q instead of axial compressive force of brace N. The relationships among N, Q and B are indicated by proposed equations (2) and (3).
 In Chapter 3 and Chapter 4, loading tests and finite element analysis about the end part model are conducted.
 From comparison with loading test results, the accuracy of finite element analysis is verified. In finite element analysis, effect of other parameters which is not regarded in loading test, i.e. D_B (diameter of buckling restrained member) and l_C (length of clevice), is investigated. These parameters cover practical conditions applied to tube-in-tube braces of building structures.
 In Chapter 5, relationship between stiffening force and local deformation at the end of the end part model is led by using the mechanical model shown in Fig. 11. The surface of the restraining member is modeled as 3 rigid bars connected by 2 hinges and horizontal springs distributed along the middle rigid bar. From the results of finite element analysis concerning deformation of buckling restrained member (Fig. 12), the stiffness of horizontal springs are obtained by Eq.(10) as the load-displacement relationship of the ring shown in Fig. 13. This ring consists of elastic part ψ and rigid part. The stiffening force is estimated as the sum of restoring force of springs and obtained by Eq.(15); it is considered that buckling restrained member becomes plastic if local deformation at the end increases to δ_y. The values of ψ and δ_y are obtained by regression equation indicated by Eq.(14) and Eq.(16). From Fig. 10 and Fig. 18, it is verified that the relationship between stiffening force and local deformation at the end is precisely predicted by Eq.(14)-Eq.(16).
 In Chapter 6, calculation results of relationship between stiffening force and local deformation at the end for pin-ended tube-in-tube brace is shown in Fig. 21. From the results, it is verified that the estimated values by Eq.(15) agrees well with the result of cyclic loading tests and finite element analysis for tube-in-tube braces⁵⁾. Based on the aforementioned results, the condition to prevent global buckling is proposed in Chapter 7.
 From this study, the validity of proposed calculation method to estimate the local deformation at the end of the buckling restrained member is verified and, consequently, the theoretical design method to prevent buckling of pin-ended tube-in-tube braces is proposed.

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 In recent years, attention to pulse type earthquakes that cause large displacement responses are concentrated. Some of them are predicted much higher than the level used in the current design, so it is promoted to set new seismic waves for design and to study about new design methods. To reduce damage of buildings against large earthquake, it has been considered to increase the elastic limit deformation using high strength steels in columns and girders. In this study, on the contrary, we propose the frames using hybrid H-section columns consist of flange with high strength steels and web with conventional strength steels, and conventional girders. In the case of using the high strength steel in columns, it is difficult to avoid the column bases of the first story being plasticized in the ultimate state. So, we consider the column base models showing stable behaviors against excessive earthquake ground motion.
 In Chapter 2, we show the damage reduction effect of the frames using hybrid columns and conventional girders by using fish bone shaped models that are taken out of single-spans from multi-layer multi-span flat frames have uniform members. In addition, it was also evaluated from the cost effectiveness. In Chapter 3, we propose the column base models which show stable behaviors against excessive earthquake ground motion. After understanding the static behavior by finite element models and multi-spring models, we evaluated the performance during earthquake by defining the index called the limit magnification. With H-SA700 as a high strength steel and SN490 as a conventional strength steel, assuming inner columns of high-rise buildings, using column base sections of small width-thickness ratio, we obtained the following results.

 (1) The frames using hybrid columns and conventional girders, compared to the frames using conventional columns and girders composed of thickened plate, have same degree of the proof stress and the cost, and also reduced more damage.
 (2) By using the frame using hybrid columns and conventional girders, we can design a high earthquake resistance building without an increase in significant cost compared to a building designed with existing standards.
 (3) To increase the limit magnification in the column bases of the first story against excessive input, it is effective to have a deformation capacity without plasticizing of high strength steels of hybrid columns.
 (4) The model obtained by adding a high strength steel in the center of the H-section composed of conventional steel can show stable behavior against about 2 times the level which is the largest Uemachi fault zone seismic. In addition, the superstructure reaches the deformation limit before the column base reaches the limit state. As a result, the performance of the building as the total collapse mechanism can be sufficiently exhibited.

 In the future, we are going to research the combination of steel species, effects of varying axial force, the case of using column base sections of large width-thickness ratio. On the other hand, Research on the application of the frames using hybrid columns and conventional girders is under way by experiments using the test piece of the column members and the cross structures. In addition, we are going to research the behavior of the column bases by experiments.

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The CHS column without a diaphragm at the beam-to-column connection undergoes local out-of-plane distortion in its cylindrical wall, which is anticipated to reduce the axial and bending strength of the column leading to premature failure during the semi-rigid action. This issue is investigated through numerical case studies in this paper. In result, the strength capacities of the non-diaphragm column are little impaired by the local deformation under vertical loads as well as horizontal forces. The ultimate state of a moment frame accommodating such a non-diaphragm connection is primarily governed by the joint failure, and the column failure follows it. The effect of column compression on joint performances is observed in the manner that the reduction in joint strength is proportional to the square of axial stress ratio.

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 1. Introduction
 The spheroidal graphite cast iron has higher mechanical strength and toughness than the flake graphite cast iron because the graphite becomes spheroidal. It has excellent properties which is damping and economy. The cast iron is better than steels for environment because steel melting point is lower and less CO₂ emissions of electric arc furnace. Today, the spheroidal graphite cast iron is used various main part that car strength parts and metal fastener of wooden building and metal fastener for joint of reinforced concrete building. However, a study performance and a case study of steel building are not conducted until now.
 2. Material properties
 This chapter show the results of four material tests which performed to grasp material properties. 2.1 round-bar tensile tests, 2.2 Charpy impact tests, 2.3 3-points bending fracture toughness tests, 2.4 circumferentially notched round-bar tensile tests.
 3. Tensile tests of tension structure joint
 This chapter show the outline and results of tensile tests of tension structure joint. The maximum tensile load and displacement at that time relationship is shown (Table. 7). The curve of tensile load P - displacement relationship by specimens shape are shown (Fig. 14).
 4. Elasto-plastic FEM of tensile tests of tension structure joint
 This chapter show the outline and results of elasto-plastic FEM of tensile tests of tension structure joint. The analysis model is shown (Fig. 15). All results of the principal stress and value of path-integral of at maximum load are shown (Table. 8-9).
 5. Consideration
 We compare the material property _pσ_c and analysis _pσ, also do material property J-integral that the crack initiation time by the experimental value of J-integral (called J_i value) and analysis path-integral. The curve of analysis _pσ - tensile stress relationship and of analysis path-integral — tensile load relationship are shown (Fig. 19-20). We compare the material property _pσ_c and mechanical properties, also do J_i. The curve of _pσ_c/σ_flow - uniform elongation relationship and J_i - _vE₀ relationship are shown (Figs. 34-35).
 6. Conclusion
 As a conclusion, the following results are obtained.
 1) _pσ is value of the maximum principal stress at analysis of tension structure joint test. _pσ_c is value of circumferentially notched round-bar tension test. _pσ is shown good correspondence with _pσ_c. Therefore, _pσ_c can be regarded as a material constant.
 2) At all of specimens of tension structure joint test, load was above to maximum load after J integral value was above J_i. J integral value increased from J_i to fracture in the materials which elongation performance is high, and we presumed that progress length of crack is come larger. Therefore, J_i can be regarded as a material constant.
 3) σflow is average value of σ_y and σ_u. The _pσ_c/σ_flow and uniform elongation relationship has linear. If uniform elongation is called ε_u, the estimate equation is _pσ_c/σ_flow=0.114ε_u+1.13.
 4) _vE₀ is absorption value in 0 degrees Celsius by Charpy impact tests. The J_i and _vE₀ relationship has generally linear. The estimate equation is J_i=0.785_vE₀+11.09.

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 The discusser can not understand some parts of the above paper. Several questions are presented here in this discussion.
 The questions are concerned with the following items.
 The items are (1) applicability of the AIJ Design Recommendations, (2) exactness of description, (3) confirmation of cone failure mode, (4) evaluation of yield shelf, and (5) definition of crack width.
 The discusser asks the authors to answer the questions.

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 The authors thank Prof. Katsuki Takiguchi for his discussion, and the answers are as follows: (1) The consideration about the applicability between the specimens and AIJ Design Recommendations was lack. (2) 6. Conclusion 5) is corrected in this answer owing to Prof. Takiguchi's discussion. (3) The reason why confirmed as the cone failure mode was that the conical shape fracture of concrete was observed around the anchor bolt head. (4) Because 6. Conclusion 4) was described the summary about the effect of the anchor bolt yielding on the declined stiffness between the load and the displacement, the yield shelf is negligible for the summary. (5) The crack was caused the rotation around the anchor bolt head, and that is defined Model II^a2). The reason why shown the maximum crack width was providing some notice for decision of damage degree.

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