鋼材腐食の進行がコンクリート表面の変形性状に与える解析的検討
角野拓真; 岡崎慎一郎; 車谷麻緒, Last
第24回コンクリート構造物の補修・補強・アップグレードシンポジウム論文集, Oct. 2024, [Reviewed]
Two-scale topology optimization for transient heat analysis in porous material considering the size effect of microstructureN. Sukulthanasorn; H. Hoshiba; K. Nishiguchi; M. Kurumatani; R. Fleischhauer; K. Ushijima; M. Kaliske; K. Terada; J. Kato, This paper presents a two-scale topology optimization framework for determining the optimal microstructure in porous material under transient heat conduction and transfer. The new optimization model, which can consider the surface area directly from microstructure topology as the size-dependent term, is introduced to enhance the heat transfer performance. In more detail, a homogenization method capable of considering the size-dependent microscopic heat transfer effect is adopted to express the microscopic material responses. A well-known material interpolation, referred to as the SIMP approach, and the design-dependent linear function are used for interpolating intermediate material properties. The minimal transient heat compliance is chosen as an objective function in this optimization problem. For the sensitivity analysis, a coupled-adjoint variable method is adopted to derive transient sensitivity formulation. The analysis shows that the proposed topology optimization model captures not only the transient heat but also the size effect of the microstructure in a transient heat analysis in porous material.
Structural and Multidisciplinary Optimization, Jul. 2022,
[Reviewed] Transient thermal porous structure designed by two-scale concurrent topology optimizationN. Sukulthanasorn; M. Kurumatani; K. Nishiguchi; J. Kato; K. Terada, The present paper proposes the novel design framework for thermal porous structure based on two-scale concurrent topology optimization subject to transient heat analysis. The optimization model considers the heat transfer through the microstructure surface to enhance the heat dissipation performance design. In particular, a well-known homogenization method incorporated the size-dependent term of microscopic heat transfer is exploited to obtain the material properties. Meanwhile, the unsteady-state heat condition is applied to the macrostructure. Furthermore, the heat compliance objective function and the derived analytical sensitivity formulations are adopted to determine the two-scale optimal topologies. As a numerical result, the concurrent design of micro-and macrostructures show the remarkable transient effect. It is also indicated that the microstructure size and the volume constraint are significant parameters for the design of heat performance.
Transactions of the Japan Society for Computational Engineering and Science, 14 Jun. 2022,
[Reviewed] A SURROGATE MODEL FOR NONLINEAR FINITE ELEMENT ANALYSIS OF REINFORCED CONCRETE BEAM AND ITS VALIDATION
Mao KURUMATANI; Toshihide SAKA; Yoshihito YAMAMOTO; Naoshi UEDA; Masayuki RYUTO and Mikito KOBAYASHI, Lead
土木学会論文集A2（応用力学）, 01 Feb. 2022, [Reviewed]
APPLICABILITY OF MODIFIED VON-MISES DAMAGE MODEL TO COMPRESSIVE FRACTURE BEHAVIOR OF CEMENT-BASED MATERIALS
Hiroto MASUI; Mao KURUMATANI, Last
土木学会論文集A2（応用力学）, 01 Feb. 2022, [Reviewed]
A nonlinear computational model for predicting flexural fracture behavior of reinforced concrete beam based on beam theory and its verification and validation
Mao Kurumatani; Toshihide Saka; Yoshihito Yamamoto; Naoshi Ueda; Shinichiro Okazaki; Hiroki Ogura, Lead
Transactions of JSCES, 17 Nov. 2021, [Reviewed]
Digital Image Correlation Analysis of Corrosion Crack Behavior in a Reinforced Concrete Member
Kato; S.; Fujimura; S.; Okazaki; S.; Kurumatani; M.; Matsushima; M.
Advances in Science and Technology, 28 Jul. 2021, [Reviewed]
MONTE CARLO SIMULATIONS ON MESO-SCALE HETEROGENEITY OF CONCRETE BY A DAMAGE MODEL
Hiromu Sasaki; Takumi Kato; Mao Kurumatani, Last
土木学会論文集A2（応用力学）, 01 Feb. 2021, [Reviewed]
Predicting the Width of Corrosion-Induced Cracks in Reinforced Concrete Using a Damage Model Based on Fracture Mechanics
Okazaki; S.; Okuma; C.; Kurumatani; M.; Yoshida; H.; Matsushima; M.
Applied Sciences, 30 Jul. 2020, [Reviewed]
Modeling of concrete’s meso-structure by phase-field method and its application to numerical experimentMao Kurumatani; Takumi Kato; Mayu Muramatsu, Lead, © 2020 by the Japan Society for Computational Engineering and Science. This paper proposes a method for modeling three-dimensional (3D) concrete’s meso-structure composed of mortar and coarse aggregates. The method consists of an automatic generation of coarse aggregates and their random arrangement in concrete’s domain. The phase-field method is applied to generate large number of coarse aggregates, each of which has arbitrary 3D shape. The aggregates are arranged randomly in concrete’s domain by repeating trial-and-error calculation with random numbers. After explaining the modeling procedure, several numerical examples are presented to demonstrate the validity and availability of the proposed method. First, the comparison of meso-scale model with an actual concrete verifies the validity of the method. The availability is then demonstrated by generating concrete’s meso-scale models with various grain size distributions. Finally, the application to a numerical experiment reveals that the proposed method allows the simulation of 3D crack propagation behavior in concrete’s meso-scale.
Transactions of JSCES, 27 May 2020,
[Reviewed] FRACTURE SIMULATION OF REINFORCED CONCRETE USING DAMAGE MODEL CONSIDERING FRICTIONAL CONTACT ON INTERFACE
Yuto Soma; Mao Kurumatani, Lead
土木学会論文集A2（応用力学）, 06 Feb. 2020, [Reviewed]
HIGH RESOLUTIONAL 3D-DIC MEASUREMENT SYSTEM AND ACCURACY VERIFICATION FOR CONCRETE SPECIMENS
Kazuya Hashiguchi; Mao Kurumatani; Shinichiro Okazaki, Corresponding
土木学会論文集A2（応用力学）, 06 Feb. 2020, [Reviewed]
SIMULTANEOUS EXPERIMENTS OF RC BEAMS FOR THE QUANTIFICATION OF UNCERTAINTY
Mao Kurumatani; Shinichiro Okazaki; Yoshihito Yamamoto; Naoshi Ueda; Hiroki Ogura, Lead
土木学会論文集A2（応用力学）, 06 Feb. 2020, [Reviewed]
Damage model for simulating fracture behavior involving frictional contact on crack face and its performance verification
Mao Kurumatani; Yuto Soma, Lead
Transactions of JSCES, 24 Jan. 2020, [Reviewed]
SIMULTANEOUS EXPERIMENTS OF RC BEAMS FOR THE QUANTIFICATION OF UNCERTAINTY
OKAZAKI Shinichirou
Journal of JSCE, Jan. 2020, [Reviewed]
EVALUATION OF CORROSION CRACK BEHAVIOR OF REINFORCED CONCRETE BY DIGITAL IMAGING CORRELATION METHOD
Y. Kabeyama; S. Fujimura; C. Ohkuma; S. Okazaki; M. Kurumatani, Last
土木学会論文集B3（海洋開発）, 09 Oct. 2019, [Reviewed]
A DAMAGE MODEL FOR MULTIPHASE COMPOSITES AND ITS VERIFICATION
Mao Kurumatani; Takumi Kato; Hiromu Sasaki, Lead
土木学会論文集A2（応用力学）, 20 Jun. 2019, [Reviewed]
Analysis of 3D crack propagation due to steel corrosion using damage model
Mao Kurumatani; Hisashi Anso; Yuto Soma; Shinichiro Okazaki, Lead
Transactions of JSCES, 31 May 2019, [Reviewed]
Simulations of cohesive fracture behavior of reinforced concrete by a fracture-mechanics-based damage model
Kurumatani; M.; Soma; Y.; Terada; K., Lead
Engineering Fracture Mechanics, 01 Feb. 2019, [Reviewed]
画像相関法による粗骨材周辺に発生・進展するひび割れの計測と可視化
車谷麻緒; 会田涼太; 橋口和哉, Lead
土木学会論文集A2（応用力学）, 31 Jan. 2019, [Reviewed]
摩擦接触を考慮した損傷モデルによる準脆性材料の破壊シミュレーション
相馬悠人; 車谷 麻緒, Last
土木学会論文集A2（応用力学）, 31 Jan. 2019, [Reviewed]
DIC計測と非線形FEMによるRCはりの変形・破壊挙動の定量的比較
車谷麻緒; 小圷祐輔; 橋口和哉; 佐々木浩武; 会田涼太; 加藤匠, Lead
土木学会論文集A2（応用力学）, 20 Dec. 2018, [Reviewed]
Simulation of crack propagation owing to deformed bar corrosion
OKAZAKI Shinichiro; Chisato Okuma; Mao Kurumatani; Hidenori Yoshida
Proceedings of the Sixth International on Life- Cycle Civil Engineering, Oct. 2018, [Reviewed]
破壊力学に基づく損傷モデルによる鉄筋コンクリートの腐食ひび割れ進展解析
大熊 千紗都; 岡崎 慎一郎; 吉田秀典; 車谷麻緒, Last
土木学会論文集B3（海洋開発）, 12 Sep. 2018, [Reviewed]
3D visualization of crack propagation in reinforced concrete by means of 3D-printing
Mao Kurumatani; Hiromu Sasaki, Lead
Transactions of JSCES, 17 May 2018, [Reviewed]
レベルセット関数を用いた形状評価によるコンクリート構造物のひび割れ自動計測
車谷麻緒; 中野 葵; 渡辺ともみ, Lead
土木学会論文集F3（土木情報学）, 26 Mar. 2018, [Reviewed]
SLAM技術に基づく空間情報を用いたAR可視化システムの構築とその適用性の検討
池田直旺; 花立 麻衣子; 樫山和男; 車谷麻緒; 吉永 崇; 前田勇司
土木学会論文集F3（土木情報学）, 26 Mar. 2018, [Reviewed]
破壊力学に基づく損傷モデルによるRC部材の大規模破壊シミュレーションに関する基礎的検討
相馬悠人; 車谷麻緒, Last
土木学会論文集A2（応用力学）, 31 Jan. 2018, [Reviewed]
鉄筋コンクリートに生じる内部ひび割れの可視化に関する実験的および解析的検討
車谷麻緒; 邊見哲一; 岡崎慎一郎, Lead
土木学会論文集A2（応用力学）, 31 Jan. 2018, [Reviewed]
コンクリート供試体の圧縮試験に対するデジタル画像相関法の計測精度に関する基礎的検討
車谷麻緒; 邊見哲一; 小圷祐輔; 橋口和哉, Lead
土木学会論文集A2（応用力学）, 31 Jan. 2018, [Reviewed]
有限ひずみ損傷モデルを用いた断層の動きに伴う表層地盤変状解析
大川真里奈; 鈴木峻; 高瀬慎介; 森口周二; 寺田賢二郎; 車谷麻緒, Last
土木学会論文集A2（応用力学）, 31 Jan. 2018, [Reviewed]
Basic study on 3D fracture simulation of reinforced concrete using finite-strain material models
Mao Kurumatani; Yuto Soma, Lead
Transactions of JSCES, 26 Jan. 2018, [Reviewed]
Damage model for simulating chloride concentration in reinforced concrete with internal cracks
M. Kurumatani; H. Anzo; K. Kobayashi; S. Okazaki; S. Hirose, Lead
Cement and Concrete Composites, 05 Sep. 2017, [Reviewed]
Phantom-node法に基づく非圧縮性オイラー型有限要素法による固体接触解析
西口浩司; 車谷麻緒; 岡澤重信; 坪倉 誠
土木学会論文集A2（応用力学）, 29 Jan. 2017, [Reviewed]
コンクリートの破壊力学に基づく損傷モデルを用いたせん断補強筋の異なるRCはりの3次元破壊シミュレーション
相馬悠人; 根本優輝; 車谷麻緒, Last
土木学会論文集A2（応用力学）, 29 Jan. 2017, [Reviewed]
損傷モデルによる内部ひび割れを有する鉄筋コンクリート中の塩化物イオン濃度の定量的評価
車谷麻緒; 小林賢司; 安藏 尚; 岡崎 慎一郎; 廣瀬壮一, Lead
土木学会論文集A2（応用力学）, 29 Jan. 2017, [Reviewed]
コンクリートの破壊力学と修正von-Mises基準に基づく等方性の有限ひずみ損傷モデル車谷麻緒; 阿部俊逸; 相馬悠人; 寺田 賢二郎, Lead, This paper presents a finite strain isotropic damage model for finite deformation FE analyses of crack propagations in concrete and reinforced concrete. The modified von-Mises criterion is extended to finite deformation problem for evaluating damage. The evolution of the damage variables is defined as the traction — separation law which is based on fracture mechanics for concrete. We first show the formulation of the proposed finite strain damage model with the modified von-Mises criterion. Several numerical experiments are presented for verification and validation of the proposed model. The mesh sensitivity in crack propagation FE analyses is verified in 1-D and 3-D problems. The FE numerical results with the damage model are then compared with the own experimental test results of 4-point bend test of RC beam without shear reinforcements., Japan Society of Civil Engineers
土木学会論文集A2（応用力学）, 20 Jan. 2017,
[Reviewed] 破壊力学的損傷を考慮したコンクリート中の物質移動解析手法の開発とその性能評価小林賢司; 車谷麻緒; 岡崎 慎一郎; 廣瀬壮一, A method for simulating mass transfer in cracked concrete by means of a damage model and finite elements is proposed in this paper. The damage model, which is based on fracture mechanics for concrete with the modified von-Mises criterion, is applied to model crack propagations in concrete. The mass transfer in concrete is represented by the unsteady diffusion equation. The diffusivity coefficients in cracked concrete are modeled by using the damage variables obtained from the crack propagation analysis with the damage model. We first show the formulation of mechanical problem with the damage model and unsteady diffusion problem in consideration of the damage. Then, after verifying the mesh-dependency and mesh-objectivity of the proposed model, the numerical FE results are compared with the experimental results available in literatures to demonstrate the validity of the proposed method., Japan Society of Civil Engineers
土木学会論文集A2（応用力学）, 22 Feb. 2016,
[Reviewed] 構造物の破壊を考慮した有限被覆法に基づく構造流体連成解析高瀬慎介; 森口周二; 寺田 賢二郎; 小山直輝; 金子賢治; 車谷麻緒; 加藤準治; 京谷孝史, This paper presents stabilized finite cover based fluid-structure interaction analysis including fracture of structure. The fracture of structure and the contact of structure uses the discrete element method using Cohesive model. The stabilized method based on SUPG/PSPG methods are employed to solve the incompressible Navier-Stokes equation. Since the physical domain is defined independently of the mathematical domain in the finite cover method, the physical boundaries of the structure are represented explicitly in a spatially fixed mesh so that the continuity condition can be imposed directly on the actual interface within the framework of Eulerian approach, and the continuity conditions of velocity and stress vectors at the interface are imposed with the penalty method. Several numerical examples are presented to demonstrate the validity and efficiency of the proposed fluid-structure interaction method., Japan Society of Civil Engineers
土木学会論文集A2（応用力学）, 22 Feb. 2016,
[Reviewed] 3D fracture simulation of reinforced concrete based on fracture mechanics for concrete and its performance assessmentMao Kurumatani; Yuki Nemoto; Yuto Soma; Kenjiro Terada, Lead, This paper presents fracture simulations of reinforced concrete involving crack propagation in concrete and plastic deformation in reinforcements. The simulation is based on the nonlinear finite element framework in which the von-Mises plasticity model and the modified von-Mises damage model are applied to reinforcement and concrete respectively. The method is also capable of simulating mesoscopic fracture behavior of reinforced concrete together with internally propagating cracks. We first show the material modeling of reinforcing bar and concrete based on the von-Mises and the modified von-Mises criterion. Several numerical experiments for material behavior are presented to verify the performance of the proposed model. The mesh sensitivity and objectivity of the proposed model is also verified in 4-point bend test of RC beam without shear reinforcements. Finally, the comparisons between numerical and experimental results show that the proposed method is able to simulate the failure behavior of RC beams with shear reinforcements and the simulation results are conformable with the experimental ones., Japan Society for Computational Engineering and Science
Transactions of JSCES, 12 Feb. 2016,
[Reviewed] An isotropic damage model based on fracture mechanics for concrete
Kurumatani; M.; Terada; K.; Kato; J.; Kyoya; T.; Kashiyama; K., Lead
Engineering Fracture Mechanics, 20 Jan. 2016, [Reviewed]
Extended voxel finite element method and its evaluationMao KURUMATANI; Haruka KAWASE, Lead, Extended voxel finite element method (X-VFEM) for the analysis of heterogeneous solids using voxel mesh is developed in this paper. The method is based on the enrichments with the level set function for material interfaces employed in the extended finite element method. To model and simulate very complex heterogeneous materials, we formulate the multiple enrichment for elements including number ofmaterial interfaces. We first formulate the X-VFEM and explain the procedure of multiple enrichment by means of level set functions and voxel data for representing complex material interfaces. In section 3, several verification examples are presented. The validity of multiple enrichment is demonstrated in 1-D tensile problem of a bar. The accuracy of stress along material interface is assessed with reference to the solutions by the standard FEM and the voxel FEM in 3-D tensile problem of a 2-phase material. In section 4, a numerical example is presented to demonstrate the effectiveness of the X-VFEM for extremely complex heterogeneous materials., Japan Society for Computational Engineering and Science
Transactions of JSCES, 11 Sep. 2015,
[Reviewed] Effect of internal crack on mass transfer resistance
Shinichiro Okazaki; Mao Kurumatani; Isao Ujike
Proceedings of Conmat’15, Sep. 2015, [Reviewed]
コンクリートのひび割れ進展計測のための画像解析手法に関する基礎的研究車谷麻緒; 松浦 遵; 根本 忍; 呉 智深, Lead, Image analysis methods based on the digital image correlation (DIC) for measuring strain distribution together with crack propagation in concrete are developed in this paper. The hierarchical modeling in the DIC is introduced to construct high resolution grids of measurement. The tracking of material points and the updating of displacement vector using finite element interpolation are also introduced to increase the accuracy of the DIC. We first show the detail of our image analysis method based on the DIC. After the validation test of strain is performed, we apply the present method to compressive tests of mortar specimen and examine how to detect crack propagations clearly. Finally, the present method is applied to concrete to visualize the complicated crack propagations due to coarse aggregates., Japan Society of Civil Engineers
土木学会論文集A2（応用力学）, 20 Feb. 2015,
[Reviewed] フェーズフィールド法によるミクロ構造トポロジー最適化の基礎的研究加藤準治; 加茂純宜; 高瀬慎介; 森口周二; 車谷麻緒; 寺田 賢二郎; 京谷孝史, It is well known that the mechanical behavior of material mainly depends on the geometric properties of the microstructure, such as material distribution, shape or size of the material. It is said that it will be possible to maximize the mechanical performance of a macro-structure, if 'types or kinds of materials to be mixed or the combinations thereof' are optimized and 'the geometric properties of micro-structure' are optimized. For this reason, the authors have developed topology optimization of microstructure using the general finite element method as a numerical approach. However, the general finite element mesh is not necessary appropriate to express the complicated real material distribution of microstructure and furthermore depends considerably on the initial value of some parameters. Thus, the present study applies a new approach,
the phase-field method, to express the complicated topology of microstructure and introduces the formulation to maximize the stiffness of the microstructure with a prescribed material volume under linear elastic regime. For the fundamental research, we firstly start from investigation of the initial value dependency of the present method on the final optimization solution by making use of a series of numerical examples., Japan Society of Civil Engineers
土木学会論文集A2（応用力学）, 20 Feb. 2015,
[Reviewed] 三次元非構造メッシュ修正システムへの要素細分化手法の導入とシステム適用性の向上研究田中 智; 樫山和男; 今西準紀; 車谷麻緒, This paper presents an interactive 3D unstructured mesh modification system using virtual reality (VR) technology. The mesh quality is evaluated and the quality is improved by the node relocation and mesh refinement. The user can change the position of nodes and refine the element in VR space by using a handy controller. The software is developed by VR programming languages; Open GL and CAVE library. The present system is applied to the mesh modification for the simulation of 3D solid analysis and is shown to be a useful tool to assist the high quality computing., Japan Society of Civil Engineers
土木学会論文集A2（応用力学）, 20 Feb. 2015,
[Reviewed] 内部ひび割れを可視化するための新奇な手法の提案
岡崎 慎一郎; 車谷 麻緒; 氏家 勲; 高本 直樹
コンクリート工学年次論文集, Jul. 2014, [Reviewed]
異形鉄筋周辺のコンクリートに形成する内部ひび割れモードの再現シミュレーション
車谷麻緒; 根本優輝; 岡崎慎一郎; 廣瀬壮一, Lead
日本計算工学会論文集, 04 Jun. 2014, [Reviewed]
微細ひび割れの形成と接触を考慮した準脆性材料の圧縮破壊シミュレーション神野真弥; 車谷麻緒; 寺田 賢二郎; 京谷孝史; 樫山和男, Corresponding, This paper proposes a method for simulating compressive failure in quasi-brittle materials involving micro- or meso-scale contact on crack interfaces. The macroscopic compressive failure is assumed to be caused by tensile and shear fractures at micro-scale, both of whose traction-crack-opening behavior is represented by the cohesive crack model. The penalty method is employed to realize the frictional contact on cracked interfaces under compressive loading. First, the discrete micro-crack behavior is introduced to a finite element framework in consideration of material inhomogeneity of cement-based materials and by using penalty springs. Then, after verifying the basic performance for simulating fracture behavior involving tensile or shear cracks, we examine the role of the micro-scale frictional contact behavior on the compressive fracture behavior. Finally, a numerical example is presented to demonstrate the validity of the proposed method in comparison with the experimental result, reported in the literature, for the compressive fracture behavior in mortar and cement paste., JAPAN SOCIETY FOR COMPUTATIONAL ENGINEERING AND SCIENCE
日本計算工学会論文集, 24 Apr. 2014,
[Reviewed] Effect of internal cracking on mass transfer resistance of cover concreteS. Okazaki; M. Kurumatani; I. Ujike; N. Takamoto, A number of studies have shown that internal cracking of cover concrete around deformed bars degrades the tightness and mass transfer resistance of the concrete member and promotes the ingress of deformed bar corrosion factors such as water, air, and various ions. However, little attention has been given to the relation between cover deterioration from internal cracking and mass transfer resistance because quantifying invisible internal cracking in concrete is difficult. In this study, a novel specimen was developed that displays internal cracking on its surface; the proposed specimen was validated by finite element analysis. An air permeability test was carried out to evaluate the deterioration in the tightness of the cover concrete because of internal cracking., CRC PRESS-TAYLOR & FRANCIS GROUP
CONCRETE SOLUTIONS: PROCEEDINGS OF CONCRETE SOLUTIONS, 5TH INTERNATIONAL CONFERENCE ON CONCRETE REPAIR, 2014,
[Reviewed] NUMERICAL EVALUATION OF TSUNAMI IMPACT FORCE ACTED ON A BRIDGE GIRDER DURING TSUNAMI BY USING A PARTICLE METHODShoichi Tanabe; Mitsuteru Asai; Kenjiro Terada; Kazuo Kashiyama; Shuji Moriguchi; Mao Kurumatani, On March 11, 2011, the huge Tsunami caused by the great east Japan earthquake devastated the Pacific coast of north-eastern Japan. Many infrastructures including bridges were collapsed by the Tsunami. New generation of Tsunami disaster prevention and mitigation method should be reconsidered toward the next millennium Tsunami. In this study, a stabilized Smoothed Particle Hydrodynamics (SPH) has been utilized for an evaluation of fluid force acted on bridge girders. In addition, a new boundary treatment using a virtual marker and fixed boundary particle is developed to satisfy the slip and no-slip boundary condition for the velocity field and to satisfy the pressure Neumann condition at the same time. The accuracy and efficiencies of our proposed method are validated by comparison between a numerical solution and experimental results. Finally, a simple treatment for the particle method has been introduced to our developed SPH tool to simulate wash out of the bridge girder., INT CENTER NUMERICAL METHODS ENGINEERING
11TH WORLD CONGRESS ON COMPUTATIONAL MECHANICS; 5TH EUROPEAN CONFERENCE ON COMPUTATIONAL MECHANICS; 6TH EUROPEAN CONFERENCE ON COMPUTATIONAL FLUID DYNAMICS, VOLS II - IV, 2014,
[Reviewed] An isotropic damage model based on fracture mechanics for concrete and its evaluationMao Kurumatani; Kenjiro Terada; Junji Kato; Takashi Kyoya; Kazuo Kashiyama, This paper proposes a new isotropic damage model for quasi-brittle materials and demonstrates its performance in crack propagation analysis for concrete. The suggested damage model is based on fracture mechanics for concrete, and is therefore capable of simulating the quasi-brittle fracture behavior with the fracture energy. We first formulate the damage model in 1-D problem by borrowing the ideas of traction-separation law based on the fracture energy of concrete. And then the damage model is extended to 2-D or 3-D problems by introducing the modified von-Mises equivalent strain. The fundamental characteristics of the suggested damage model are examined in chapter 3. We evaluate the energy balance in 3-point bend test specimen with a single-edge notch, and verify the mesh objectivity of finite element solution with the damage model. Finally, a benchmark test characterized by mixed-mode fracture, which is called Nooru-Mohamed Test, is performed to demonstrate the capability of the suggested damage model. © 2013 The Japan Society For Computational Engineering and Science.
Transactions of the Japan Society for Computational Engineering and Science, 2013,
[Reviewed] 破壊シミュレーションのための構造要素を用いた離散体解析法
車谷麻緒; 寺田賢二郎; 京谷孝史; 加藤準治; 樫山和男, Lead
日本計算工学会論文集, 2013, [Reviewed]
粗骨材の幾何学的非均質性に着目したコンクリートの圧縮破壊シミュレーション
車谷麻緒; 神野真弥; 寺田賢二郎, Lead
土木学会論文集A2（応用力学）, 2013, [Reviewed]
コンクリートの破壊力学に基づく等方性損傷モデルの定式化とその性能評価
車谷麻緒; 寺田賢二郎; 加藤準治; 京谷孝史; 樫山和男, Lead
日本計算工学会論文集, 2013, [Reviewed]
一般化有限要素法による不連続性の近似に関する比較考察
車谷麻緒; 寺田賢二郎, Lead
土木学会論文集A2（応用力学）, 2012, [Reviewed]
土木工学における計算力学手法の研究動向
応用力学委員会; 計算力学小委員会
土木学会論文集A2（応用力学）, 2012, [Reviewed]
A method of global-local analyses of structures involving local heterogeneities and propagating cracksKurumatani; M.; Terada; K, Lead, This paper presents the global-local finite cover method (GL-FCM) that is capable of analyzing structures involving local heterogeneities and propagating cracks. The suggested method is composed of two techniques. One of them is the FCM, which is one of the PU-based generalized finite element methods, for the analysis of local cohesive crack growth. The mechanical behavior evaluated in local heterogeneous structures by the FCM is transferred to the overall (global) structure by the so-called mortar method. The other is a method of mesh superposition for hierarchical modeling, which enables us to evaluate the average stiffness by the analysis of local heterogeneous structures not subjected to crack propagation. Several numerical experiments are conducted to validate the accuracy of the proposed method. The capability and applicability of the proposed method is demonstrated in an illustrative numerical example, in which we predict the mechanical deterioration of a reinforced concrete (RC) structure, whose local regions are subjected to propagating cracks induced by reinforcement corrosion., TECHNO-PRESS
Structural Engineering and Mechanics, 2011,
[Reviewed] X-FEMによる非均質材料の波動伝搬解析に関する基礎的研究
車谷麻緒; 寺田賢二郎; 京谷孝史, Lead
土木学会論文集A2（応用力学）, 2011, [Reviewed]
有限被覆法に基づく自由表面を有する流体.構造連成解析手法の構築
中村正人; 高瀬慎介; 樫山和男; 寺田賢二郎; 車谷麻緒, Last
土木学会論文集A2（応用力学）, 2011, [Reviewed]
Eulerian finite cover method for solid dynamicsS. Okazawa; H. Terasawa; K. Kashiyama; M. Kurumatani; K. Terada, In order to deal with the kinematic and dynamic boundary conditions in the Eulerian framework, we develop an Eulerian finite cover method (FCM) for large deformation solid dynamics by incorporating the approximation strategy of the FCM into the existing Eulerian explicit finite element method. The operator split method is employed to solve Eulerian solid dynamics problems, and the resulting numerical algorithm consists of two steps. One is the nonadvective step, in which the standard Lagrangian FC analysis is carried out with the explicit time integration scheme, and the other is the advective step, in which the CIVA method is applied to project the solution obtained in the nonadvective step to the Eulerian mesh. Two representative numerical examples are presented to validate the proposed Eulerian FCM and demonstrate its capability especially in appropriately treating the kinematic and dynamic boundary conditions., WORLD SCIENTIFIC PUBL CO PTE LTD
International Journal of Computational Methods, 2010,
[Reviewed] A method of two-scale thermo-mechanical analysis for porous solids with micro-scale heat transferK. Terada; M. Kurumatani; T. Ushida; N. Kikuchi, A two-scale thermo-mechanical model for porous solids is derived and is implemented into a multi-scale multi-physics analysis method. The model is derived based on the mathematical homogenization method and can account for the scale effect of unit cells, which is our particular interest in this paper, on macroscopic thermal behavior and, by extension, on macroscopic deformation due to thermal expansion/contraction. The scale effect is thought to be the result of microscopic heat transfer, the amount of which depends on the micro-scale pore size of porous solids. We first formulate a two-scale model by applying the method of asymptotic expansions for homogenization and, by using a simple numerical model, verify the validity and relevancy of the proposed two-scale model by comparing it with a corresponding single-scale direct analysis with detailed numerical models., SPRINGER
Computational Mechanics, 2010,
[Reviewed] Two-scale diffusion-deformation coupling model for material deterioration involving micro-crack propagationK. Terada; M. Kurumatani, Last, In this paper, we introduce a two-scale diffusion deformation coupled model that represents the aging material deterioration of two-phase materials involving micro-crack propagations. The mathematical homogenization method is applied to relate the micro- and macroscopic field variables, and a weak coupling solution method is employed to solve the two-way coupling phenomena between the diffusion of scalar fields and the deformation of quasi-brittle solids. The macroscopic mechanical behavior represented by the derived two-scale two-way coupled model reveals material nonlinearity due to micro-scale cracking induced by the scalar-field-induced deformation, which can be simulated by the finite cover method. After verifying the fundamental validity of the proposed model and the analysis method, we perform a simple numerical example to demonstrate their ability to predict aging material deterioration. Copyright (C) 2010 John Wiley & Sons, Ltd., JOHN WILEY & SONS LTD
International Journal for Numerical Methods in Engineering, 2010,
[Reviewed] 微細ひび割れの形成・連結・開閉に起因した準脆性材料の破壊進行メカニズム
車谷麻緒; 寺田賢二郎; 竹内則雄, Lead
土木学会論文集A, 2010, [Reviewed]
構造物のエネルギー収支に着目した準脆性材料の破壊靱性評価法に関する基礎的研究
車谷麻緒; 湯本達也; 寺田賢二郎; 京谷孝史; 秋山充良, Lead
応用力学論文集, 2010, [Reviewed]
超高強度セメントペースト微細構造のひび割れ挙動解析と圧縮強度評価
笹川崇; 車谷麻緒; 寺田賢二郎; 閑田徹志; 全振煥; 百瀬晴基
応用力学論文集, 2010, [Reviewed]
エネルギー収支に基づくコンクリートの破壊靭性評価法に関する基礎的研究
車谷麻緒; 湯本達也; 寺田賢二郎; 秋山充良
コンクリート工学年次論文報告集, 2009
Finite cover method with multi-cover-layers for the analysis of evolving discontinuities in heterogeneous mediaM. Kurumatani; K. Terada, Lead, We extend the finite cover method (FCM), which is known as a generalized finite element method, to crack simulations for quasi-brittle heterogeneous solids by using only a regular structured mathematical mesh. The proposed version of the FCM is powered by a method of modeling arbitrary numbers of physical cover layers. This 'multi-cover layer modeling' relies crucially on not only the introduction of multiple layers of physical covers, each of which is associated with a single physical domain, but also the identification of the values of level-set functions for discontinuities, which can be evaluated from their digital image information. Several numerical examples are presented to demonstrate the successful mesh-based mesh-free analyses of heterogeneous solids with arbitrarily evolving cracks and interfacial debonding thanks to the introduction of multiple cover layers. Copyright (C) 2009 John Wiley & Sons, Ltd., JOHN WILEY & SONS LTD
International Journal for Numerical Methods in Engineering, 2009,
[Reviewed] 準脆性材料の離散ひび割れ進展解析手法の開発とその混合モード破壊への応用
車谷麻緒; 寺田賢二郎; 京谷孝史; 橋詰知尚, Lead
土木学会論文集A, 2009, [Reviewed]
材料内部の微細ひび割れ形成に着目した準脆性材料の寸法効果発現メカニズム
車谷麻緒; 寺田賢二郎, Lead
土木学会論文集A, 2009, [Reviewed]
グローバル・ローカル有限被覆法の開発とRC構造物の腐食ひび割れ進展解析への応用
車谷麻緒; 寺田賢二郎, Lead
土木学会論文集A, 2008, [Reviewed]
微視的ひび割れ進展を考慮した経年的材料劣化のマルチスケール・マルチフィジックス解析
車谷麻緒; 寺田賢二郎, Lead
土木学会論文集A, 2008, [Reviewed]
Cohesive crackモデルに対する陽的近似アルゴリズムの提案とその性能評価
車谷麻緒; 寺田賢二郎, Lead
土木学会論文集A, 2008, [Reviewed]
Cohesive crackモデルに対する陽的近似アルゴリズムの3次元ひび割れ進展問題への応用
車谷麻緒; 寺田賢二郎; 京谷孝史, Lead
応用力学論文集, 2008, [Reviewed]
多孔質体の微視的寸法を考慮した均質化法に基づく熱・固体変形のマルチスケール・マルチフィジックス解析
車谷麻緒; 寺田賢二郎; 奥村弘, Lead
日本計算工学会論文集, 2008, [Reviewed]
鉄筋の腐食膨張のモデル化とコンクリートのひび割れ挙動の数値解析
車谷麻緒; 寺田賢二郎; 久田真
土木学会論文集A, 2007, [Reviewed]
Eulerian finite cover method for quasi-static equilibrium problems of hyperelastic bodiesK. Terada; A. Maruyama; M. Kurumatani, We introduce a Eulerian finite cover method that realizes implicit structural analyses for hyperelastic bodies in quasi-static equilibrium by using both the Lagrangian and the Eulerian mathematical meshes simultaneously. The recursive covering of the equilibrated current configuration determined with the Lagrangian mesh by the Eulerian mesh provides the reference configuration in the corresponding time interval, after the physical quantities on the former are mapped onto the latter. Several numerical examples are presented to demonstrate the capability of the method, to assess its validity, and to address a remark on the mapping process of physical quantities. Copyright (C) 2006 John Wiley & Sons, Ltd., JOHN WILEY & SONS LTD
Communications in Numerical Methods in Engineering, 2007,
[Reviewed] 節点積分有限要素法の変形・近似性能に関する基礎的検討
車谷麻緒; 小島隆嗣; 寺田賢二郎, Lead
日本計算工学会論文集, 2007, [Reviewed]
複合材料の非線形解析のためのイメージベース節点積分有限要素法
車谷麻緒; 寺田賢二郎, Lead
応用力学論文集, 2007, [Reviewed]
領域分割問題における有限要素メッシュ界面の接合手法について
車谷麻緒; 寺田賢二郎, Lead
土木学会論文集A, 2006, [Reviewed]
均質化法に基づく濃度・変位場のマルチスケール連成解析手法
車谷麻緒; 寺田賢二郎, Lead
土木学会論文集A, 2006, [Reviewed]
多孔質体微視領域での熱伝達を考慮した均質化法に基づくマルチスケール熱伝導解析
車谷麻緒; 寺田賢二郎, Lead
土木学会論文集A, 2006, [Reviewed]
有限被覆近似における一般化要素の界面近似特性（界面を含む一般化要素のパッチテスト）
車谷麻緒; 寺田賢二郎, Lead
日本計算工学会論文集, 2006, [Reviewed]
多重被覆モデリングによる有限被覆法（非均質脆性材料の不連続面進展解析）
車谷麻緒; 寺田賢二郎
日本計算工学会論文集, 2006, [Reviewed]
高次有限被覆近似に基づく一般化要素の近似性能に関する一考察
車谷麻緒; 寺田賢二郎, Lead
土木学会論文集, 2005, [Reviewed]
An integrated procedure for structural analysis with the finite cover methodK. Terada; M. Kurumatani, In this paper an integrated procedure for three-dimensional (3D) structural analyses with the finite cover method (FCM) is introduced. In the pre-process of this procedure, the geometry of a structure is modelled by 3D-CAD, followed by digitization to have the corresponding voxel model, and then the structure is covered by a union of mathematical covers, namely a mathematical mesh independently generated for approximation purposes. Since the mesh topology in the FCM does not need to conform to the physical boundaries of the structure, the mesh can be regular and structured. Thus, the numerical analysis procedure is free from the difficulties mesh generation typically poses and, in this sense, enables us to realize the mesh-free analysis. After formulating the FCM with interface elements for the static equilibrium state of a structure, we detail the procedure of the finite cover modelling, including the geometry modelling with 3D-CAD and the identification of the geometry covered by a regular mesh for numerical integration. Prior to full 3D modelling and analysis, we present a simple numerical example to confirm the equivalence of the performance of the FCM and that of the standard finite element method (FEM). Finally, representative numerical examples are presented to demonstrate the capabilities of the proposed analysis procedure. Copyright (c) 2005 John Wiley & Sons, Ltd., JOHN WILEY & SONS LTD
International Journal for Numerical Methods in Engineering, 2005,
[Reviewed] Finite cover method with mortar elements for elastoplasticity problemsM. Kurumatani; K. Terada, Lead, Finite cover method (FCM) is extended to elastoplasticity problems. The FCM, which was originally developed under the name of manifold method, has recently been recognized as one of the generalized versions of finite element methods (FEM). Since the mesh for the FCM can be regular and squared regardless of the geometry of structures to be analyzed, structural analysts are released from a burdensome task of generating meshes conforming to physical boundaries. Numerical experiments are carried out to assess the performance of the FCM with such discretization in elastoplasticity problems. Particularly to achieve this accurately, the so-called mortar elements are introduced to impose displacement boundary conditions on the essential boundaries, and displacement compatibility conditions on material interfaces of two-phase materials or on joint surfaces between mutually incompatible meshes. The validity of the mortar approximation is also demonstrated in the elastic-plastic FCM., SPRINGER
Computational Mechanics, 2005,
[Reviewed] 不連続Galerkin有限被覆法の開発とその性能評価
車谷麻緒; 寺田賢二郎, Lead
応用力学論文集, 2005, [Reviewed]
Performance assessment of generalized elements in the finite cover methodK. Terada; M. Kurumatani, We perform numerical experiments to assess the performance of generalized elements that partially have a physical domain in the context of the finite cover method (FCM). The partial physical domain of interest is in a rectangular or an arbitrary shape and the comparison is made with the standard finite element model (FEM). We also report the appearance of cancellation errors in assembling elemental matrices and vectors and in treating essential boundary conditions. After making a simple convergence study, we conclude that the performance of generalized elements in the FCM are equivalent to or slightly superior to that of the FEM. (C) 2004 Elsevier B.V. All rights reserved., ELSEVIER SCIENCE BV
Finite Elements in Analysis and Design, 2004,
[Reviewed] 有限被覆法における一般化要素の近似性能に関する基礎的研究
車谷麻緒; 寺田賢二郎, Lead
日本計算工学会論文集, 2003, [Reviewed]
