日本建築学会構造系論文集
Online ISSN : 1881-8153
Print ISSN : 1340-4202
ISSN-L : 1340-4202
77 巻, 680 号
選択された号の論文の15件中1~15を表示しています
  • 松沢 晃一, 橘高 義典
    2012 年 77 巻 680 号 p. 1477-1483
    発行日: 2012/10/30
    公開日: 2013/04/25
    ジャーナル フリー
    This paper reports on the investigation into the fracture properties of concrete subjected to the effect of high temperature heating up to 800°C. Wedge splitting tests were conducted to measure the load versus crack mouth opening displacement curves. The initial cohesive stress and fracture energy were estimated by the inverse analysis of tension softening diagram calculated by the load versus crack mouth opening displacement curves. As a result, the effect of high temperature heating on the fracture properties was discussed.
  • 金 容徹, 吉田 昭仁, 田村 幸雄
    2012 年 77 巻 680 号 p. 1485-1492
    発行日: 2012/10/30
    公開日: 2013/04/25
    ジャーナル フリー
    A large number of wind pressure measurements were performed to investigate the influence of upstream surrounding buildings on the wind pressures and forces on a cubical low-rise building. The primary purpose of the present study was to understand the effects of proximity buildings by introducing the two different normalization methods for the wind pressures and to examine the methodology of design application. The considered parameters were the area densities and long upstream distance under the turbulent boundary layer representing a suburban area. Results show that wind pressures decrease with increasing area density, but the variations of mean and fluctuating components within one area density are relatively small. And most of the increases in the local wind pressure coefficients originate from the rapid decrease in local velocity pressures at the model position. And by using the interference factor which is an exponential function of area density only, it was found that the wind loads on structural frames and component/cladding element of the target low-rise building in group can be easily evaluated.
  • 山口 陽司, 仲野 一秀, 宮本 裕司
    2012 年 77 巻 680 号 p. 1493-1499
    発行日: 2012/10/30
    公開日: 2013/04/25
    ジャーナル フリー
    During the 1995 Hyogo-ken Nanbu earthquake, building damages concentrated in the southern part of Toyonaka city. Most of the damaged buildings were wooden houses. In this study, we evaluate the ground motions to clarify the cause of damages concentration in Toyonaka city. 2D FEM models of the deep underground are analyzed considering irregular structures by Uemachi fault running north-south of Toyonaka. The observed record at the surface near Toyonaka city was used to estimate the input motion. 1D nonlinear analyses of the surface soils are also carried out on the basis of boring data.
  • 日下 彰宏, 鈴木 康嗣, 安達 直人, 岩本 賢治, 中島 正愛
    2012 年 77 巻 680 号 p. 1501-1509
    発行日: 2012/10/30
    公開日: 2013/04/25
    ジャーナル フリー
    A vibration test for a 9-story building shows that fractures at steel beam-to-column connections change the vertical vibration characteristics at the center of the beams. By use of the result, this study proposes a fracture detecting method, in which beam vibration modes are compared by MAC (modal assurance criterion) value each other, then, fractures are detected to locate at beams related with peculiar MAC values.
    Finite element method analysis is executed for the 9-story building to examine the proposed method. MCS (Monte Carlo Simulation) is also executed in order to consider the effect of variation in beam vibration, which is found in practical buildings. The MCS shows that even with 15% of the maximum displacement of beam as variation, which is around half of that measured in a test for a 3-story building, the proposed method can be informative for fracture detection. Future works are to develop the criteria to judge whether to be fractured as well as to accumulate the data on practical buildings.
  • 内接円を持つ四角形,等脚台形,直角を2つ持つ台形の場合
    野村 圭介, 諸岡 繁洋
    2012 年 77 巻 680 号 p. 1511-1516
    発行日: 2012/10/30
    公開日: 2013/04/25
    ジャーナル フリー
    The purpose of this study is to propose calculation formula of maximum deflection and the maximum bending moments of arbitrary shape of slabs, and we treat fixed end quadrilateral slab such as tangential quadrilateral, isosceles trapezoid and right-angled trapezoid subjected to uniform load in this paper. In our previous paper, we proposed the calculation formula of arbitrary triangle slab, where we found out main variables and their compositions of the calculation formula from FEM solutions and we assumed FEM solutions to be the targeted values. In the triangle slab, the main variable was found to be inradius of inscribed circle, because the maximum deflection generally occurs at the further point from the sides and the point is the incenter. So in first half of this paper, we consider whether the calculation formula of tangential quadrilateral slab can be formulated by the same variable. Furthermore, we consider that trapezoid slab is more practical shape, and formulate the calculation formula of that.
  • 森 隆浩, 加藤 秀章, 室田 伸夫
    2012 年 77 巻 680 号 p. 1517-1526
    発行日: 2012/10/30
    公開日: 2013/04/25
    ジャーナル フリー
    In this study, we propose FEM analysis model and time history response analysis model for high damping rubber bearings. These models can be used for the condition of repeated deformation which is often caused by the long-period ground motion or wind response. In this condition, high damping rubber bearings experience stiffness degradation due to fatigue and temperature increase of inner rubber. First, by taking account of these two effects, we establish the constitutive law of high damping rubber material for FEM analysis model and check the reproductivity of test results. Next, we derive the hysteresis model from the constitutive law of high damping rubber material. A prediction equation of temperature increase for the hysteresis model is determined from thermal FEM analysis.
  • 間瀬 辰也, 中井 正一
    2012 年 77 巻 680 号 p. 1527-1535
    発行日: 2012/10/30
    公開日: 2013/04/25
    ジャーナル フリー
    This paper describes the evaluation method of soil springs in the design of the pile foundation in which a pile is expressed with beam elements and the ground with soil springs of horizontal and vertical directions. The proposed model of soil springs is based on the concept of the subloading surface model that realizes a smooth transition from elastic state to plastic state of the soil. Simulation analyses of lateral and vertical loading tests in an actual ground were carried out by using the proposed model. The computed results show a fairly good agreement with the test results.
  • 濱田 純次, 麻生 直木, 花井 厚周, 山下 清
    2012 年 77 巻 680 号 p. 1537-1544
    発行日: 2012/10/30
    公開日: 2013/04/25
    ジャーナル フリー
    Seismic observation on piled raft foundation subjected to unsymmetrical earth pressure was performed since after the 2011 off the Pacific Coast of Tohoku Earthquake. Accelerations of building, dynamic sectional forces of piles and dynamic earth pressures on both sides of an embedded foundation and beneath a raft were observed at 235 seismic events including an earthquake magnitude of Me7.1. The maximum acceleration of 32.2 cm/s2 was observed on building foundation. Based on the seismic record, it is confirmed that a lateral inertial force of the building is related to shear forces and bending moments of piles, and lateral resistant force beneath the raft. It was also found that lateral load sharing ratio of piles was estimated about 10 to 20 % of the inertial force of building from observed record. The load sharing ratio between piles and raft and bending moments of pile could be approximately explained by simplified theoretical equations.
  • エネルギーの釣合に基づく地盤の地震時挙動の評価に関する研究 その3
    下村 修一, 安達 俊夫, 朝枝 亮太, 酒句 教明
    2012 年 77 巻 680 号 p. 1545-1552
    発行日: 2012/10/30
    公開日: 2013/04/25
    ジャーナル フリー
    The main purpose of this study is to form an evaluation method of the ground motion caused by an earthquake on the basis of the energy balance concept. The relationship between the ground settlement (volume strain) and the accumulate plastic strain energy should be investigated to conduct the proposed method for predicting the ground settlement. In this paper, it is demonstrated that the ground settlement is strongly dependent on the accumulate plastic strain energy through the cyclic undrained shear tests. Further, the simulation analysis of the shaking table test results with the large shear box and the simulation analysis of the actual seismic damage are conducted to discuss the applicability of the proposed method. From the simulation analyses results, it is confirmed that the proposed method can approximately predict the measurement value of the ground settlement that is the wide range value from 0 to 50 cm.
  • 望月 英二
    2012 年 77 巻 680 号 p. 1553-1560
    発行日: 2012/10/30
    公開日: 2013/04/25
    ジャーナル フリー
    The embedment in orthogonal direction of fibers is a major structural element of timber structures. The relationship between axial force and bending moment considering geometric separation of members and yield of material is discussed and some formulae for analyses are derived. A simple modeling method for analysis is devised from the formulae. Comparison between results of an experiment and elasto-plastic analyses in keeping with the method shows the effectiveness and the limitation of the formulae and the method.
  • 長岡 修, 五十田 博, 槌本 敬大, 清水 秀丸
    2012 年 77 巻 680 号 p. 1561-1568
    発行日: 2012/10/30
    公開日: 2013/04/25
    ジャーナル フリー
    This paper presents the p-delta effect and collapse limit state for wooden structures. The static lateral loading tests of walls were conducted to evaluate the p-delta effect and rocking behavior using the wall specifications, width, live load and column-beam connection type, as parameters. Also the load-displacement relationship under a collapse test of a full-sized wooden house was followed using the outcome from shear wall tests. The results of the shear wall tests and following of the load-displacement relationship in a full-sized wooden house are summarized:
    1) The bracing and plywood shear wall are close to the column-beam simple frame in the shear performance without making contact with the base beyond 0.1 radium displacement. The collapse limit state cannot be expressed using the shear performance of the frame only. 2) The P-delta effect and rocking behavior are calculated based on the consideration of vertical load, tensile performance of column-beam joints and widths of the walls. 3) The load-displacement relationship and collapse limit state are predicted based on consideration of the contact of panels with the foundation and floor.
  • ポリマーセメントモルタルを用いて補強したそで壁付き柱の構造性能 その1
    杉山 智昭, 松崎 育弘
    2012 年 77 巻 680 号 p. 1569-1578
    発行日: 2012/10/30
    公開日: 2013/04/25
    ジャーナル フリー
    This paper proposes a seismic retrofitting technique for existing RC columns with cast-in-place RC sidewall using polymer-cement mortar. In the technique, additional shear reinforcement (deformed steel bar: prefabricated reinforcing unit) is adhered to the surface of existing RC columns with RC sidewall by using polymer-cement mortar. Shear-loading tests of the RC columns with RC sidewall were conducted to clarify the structural performance of the columns with sidewall strengthened by polymer-cement mortar. The results suggested that the technique improved the shear capacity of the RC columns with RC sidewall, and clarified the mechanism of shear resistance of the strengthened columns with sidewall. Furthermore, a method of estimating the shear strength of RC columns with RC sidewall strengthened by polymer-cement mortar was proposed by modeling the shear resistance mechanism.
  • - 免震構造用U字形鋼材ダンパーの水平2方向特性 その1 -
    吉敷 祥一, 高山 大, 山田 哲, エネ ディアナ, 小西 克尚, 川村 典久, 寺嶋 正雄
    2012 年 77 巻 680 号 p. 1579-1588
    発行日: 2012/10/30
    公開日: 2013/04/25
    ジャーナル フリー
    Evaluation of bi-directional characteristics of base-isolation devices is a very important issue for base-isolated structures. This paper describes a bi-directional loading test of U-shaped steel dampers widely-used for energy dissipation in base-isolated structures. The major findings obtained from the test are as follows: (1) torsion-induced residual deformation leads to contact with damper connections; (2) evaluation method of cyclic deformation capacity, which divides bi-directional orbit into deformations in 0 and 90 degree, is proposed and the validity is verified; (3) cyclic deformation capacity is reduced by cumulative torsion; (4) two indices Jc and Jf proposed in this paper can evaluate the limitation of cumulative torsion until contact with connections and the tendency of torsioninduced reduction of cyclic deformation capacity.
  • 耐震壁に新設開口を有する既存壁式プレキャスト鉄筋コンクリート構造集合住宅建物の耐震性能評価 その2
    下錦田 聡志, 高木 次郎, 見波 進, 北山 和宏
    2012 年 77 巻 680 号 p. 1589-1598
    発行日: 2012/10/30
    公開日: 2013/04/25
    ジャーナル フリー
    In order to utilize existing wall-type precast reinforced concrete (WPC) residential buildings, which were constructed more than 30 years ago maintaining high structural performance and good quality, the authors created static pushover analysis models, which are composed of elastic line elements and inelastic joint springs. The analyses showed that the ultimate seismic strength coefficient in short side direction (CQ1) was approximately 0.6 and rocking of the multi-story walls was the collapse mechanism. In this research, full-scale experiment of the joint was conducted, in order to investigate its vertical restoring force characteristics. In addition to the improvement of the joint models, coupling beams were newly included in the analysis models. Consequently, CQ1 increased to 0.68-0.72 and the mechanism was the rocking associated with shear failure of the beams. Furthermore, the analyses were compared with the result from Japanese simple seismic performance evaluation method. The contribution of the coupling beams may be overestimated in the method.
  • 林 和宏, 柳沢 学, 柴田 道生
    2012 年 77 巻 680 号 p. 1599-1604
    発行日: 2012/10/30
    公開日: 2013/04/25
    ジャーナル フリー
    Exterior columns of Steel-Reinforced Concrete (SRC) structures are often composed of non-symmetric steel sections (e.g., tee section) embedded in concrete. However, due to the non-symmetricity, the full plastic moments in the weak-axis bending are not explicitly available for such SRC columns. The current design code (i.e., the AIJ standard for structural calculation of SRC structures) has a provision for weak-axis calculations but, in some cases, may lead to significant underestimation of member strength due to its poor approximation. This paper proposes new approximate design formulas with good accuracy for the weak-axis bending and bi-axial bending full plastic moments for non-symmetric SRC columns. The proposed design formula shows great agreements with high-fidelity numerical solutions.
feedback
Top