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Damage-constitutive model for seawater coral concrete using different stirrup confinements subjected

《结构与土木工程前沿（英文）》 2023年 第17卷 第3期   页码 429-447 doi: 10.1007/s11709-022-0913-2

摘要： Recently, the application of detrital coral as an alternative to natural aggregates in marine structures has attracted increased attention. In this study, research on the compressive performance of coral aggregate concrete (CAC) confined using steel stirrups with anti-rust treatment was experimentally conducted. A total of 45 specimens were cast, including 9 specimens without stirrups and under different strength grades (C20, C30, and C40) and 36 specimens under different strength grades (C20, C30, and C40). Moreover, three stirrup levels (rectangular, diamond-shaped compound, and spiral stirrups) and different stirrup spacings (40, 50, 60, and 70 mm) were used. Subsequently, the stress−strain curves of specimens subjected to axial loading were measured. The effects of the stirrup spacing and stirrup configurations on the stress and strain were investigated, respectively, and the lateral effective stress of the different stirrups was calculated based on the cohesive-elastic ring model and modified elastic beam theory. Moreover, a damage-constitutive model of CAC considering the lateral stress was set up based on damage mechanics theory. The results indicated an increase in the stress and strain with a decrease in the stirrup spacing, and the adopted stirrup ratio had a better strengthening effect than the different concrete grades, and the variation in the deformation was restricted by the performance of coral coarse aggregate (CA). However, an increment in the lateral strain was observed with an increase in the axial strain. The lateral stress model showed a good agreement with the experimental data, and the proposed damage-constitutive model had a good correlation with the measured stress−strain curves.

关键词： coral aggregate concrete     stress−strain curves     lateral effective stress     peak stress     axial−lateral curves     damage-constitutive model.    

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Endochronic damage constitutive model for fully-graded aggregate mass concrete

SONG Yupu, WANG Huailiang

《结构与土木工程前沿（英文）》 2007年 第1卷 第3期   页码 274-280 doi: 10.1007/s11709-007-0035-x

摘要： The behavior of deformation and strength of a fully-graded aggregate concrete under complex stress state is the basis of the nonlinear analysis and design for mass concrete structures such as concrete dams. In this paper, based on the combined endochronic theory with damage mechanics and on the quantities of experimental data, an endochronic damage constitutive model suitable for various aggregate grade concrete is proposed. This model takes into consideration the scale effect and the effect of wet screen sieve of aggregate in which the concept of yield surface is not needed and the difference of damage evolution rule of various graded aggregate concrete is a concern. The proposed model is used to analyze the deformation and strength of fully-graded aggregate mass concrete and the wet screened aggregate concrete specimens. The calculated results are in good agreement with experimental data, which can be used as a guide for the design of arch dams and other mass concrete structures.

关键词： concept     surface     design     concern     strength    

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Development of a constitutive model for rockfills and similar granular materials based on the disturbed

Mehdi VEISKARAMI, Ali GHORBANI, Mohammadreza ALAVIPOUR

《结构与土木工程前沿（英文）》 2012年 第6卷 第4期   页码 365-378 doi: 10.1007/s11709-012-0178-2

摘要： Behavior of rockfills was investigated experimentally and theoretically. A series of standard triaxial compression tests were carried out on a quarried rockfill material at different stress levels. It was found that both the stress level and the shear stress ratio, like most of granular materials, controls the behavior of rockfill materials. At lower shear stress ratios the behavior is much more similar to a nonlinear elastic solid. When the shear stress goes further, the stress-strain curve shows an elasto-plastic behavior which suggests using the disturbed state concept to develop a constitutive model to predict the stress-strain behavior. The presented constitutive model complies reasonably with the experimental data.

关键词： constitutive model     granular material     rockfill     plasticity     disturbed state concept     stress level    

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Cyclic behavior of prefabricated reinforced concrete frame with infill slit shear walls

Kui XIAO,Qilin ZHANG,Bin JIA

《结构与土木工程前沿（英文）》 2016年 第10卷 第1期   页码 63-71 doi: 10.1007/s11709-015-0294-x

摘要： A composite structural system consisting of prefabricated reinforced concrete frame with infill slit shear walls (PRCFW), with good ductility, is a new type of earthquake resistant structure. Pseudo-static tests were performed to evaluate the seismic behavior of the PRCFW system. Two one-bay, two-story PRCFW specimens were both built at one-half scale. Additional computational research is also conducted to enhance the nonlinear analytical capabilities for this system. Combined with the concrete damaged plastic (CDP) model provided by finite element program ABAQUS and the constitutive model of concrete proposed by Chinese code, the damage process of the PRCFW structure under cyclic load is simulated. The simulated results show a good agreement with the test data, the dynamic behavior of the PRCFW system can be simulated sufficiently accurate and efficient to provide useful design information. The experimental and numerical study show that this system has the potential to offer good ductility and energy absorption capacity to dissipate input energy, and stiffness adequate for controlling drift for buildings located in earthquake-prone regions.

关键词： slit shear wall     constitutive model     cyclic     seismic     damage    

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Unified description of sand behavior

Feng ZHANG, Bin YE, Guanlin YE

《结构与土木工程前沿（英文）》 2011年 第5卷 第2期   页码 121-150 doi: 10.1007/s11709-011-0104-z

摘要： In this paper, the mechanical behavior of sand, was systematically described and modeled with a elastoplastic model proposed by Zhang et al. [ ]. Without losing the generality of the sand, a specific sand called as Toyoura sand, a typical clean sand found in Japan, has been discussed in detail. In the model, the results of conventional triaxial tests of the sand under different loading and drainage conditions were simulated with a fixed set of material parameters. The model only employs eight parameters among which five parameters are the same as those used in Cam-clay model. Once the parameters are determined with the conventional drained triaxial compression tests and undrained triaxial cyclic loading tests, then they are fixed to uniquely describe the overall mechanical behaviors of the Toyoura sand, without changing the values of the eight parameters irrespective of what kind of the loadings or the drainage conditions may be. The capability of the model is discussed in a theoretical way.

关键词： constitutive model     sand     stress-induced anisotropy     density     structure    

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An enhanced damage plasticity model for predicting the cyclic behavior of plain concrete under multiaxial

Mohammad Reza AZADI KAKAVAND, Ertugrul TACIROGLU

《结构与土木工程前沿（英文）》 2020年 第14卷 第6期   页码 1531-1544 doi: 10.1007/s11709-020-0675-7

摘要： Some of the current concrete damage plasticity models in the literature employ a single damage variable for both the tension and compression regimes, while a few more advanced models employ two damage variables. Models with a single variable have an inherent difficulty in accounting for the damage accrued due to tensile and compressive actions in appropriately different manners, and their mutual dependencies. In the current models that adopt two damage variables, the independence of these damage variables during cyclic loading results in the failure to capture the effects of tensile damage on the compressive behavior of concrete and vice-versa. This study presents a cyclic model established by extending an existing monotonic constitutive model. The model describes the cyclic behavior of concrete under multiaxial loading conditions and considers the influence of tensile/compressive damage on the compressive/tensile response. The proposed model, dubbed the enhanced concrete damage plasticity model (ECDPM), is an extension of an existing model that combines the theories of classical plasticity and continuum damage mechanics. Unlike most prior studies on models in the same category, the performance of the proposed ECDPM is evaluated using experimental data on concrete specimens at the material level obtained under cyclic multiaxial loading conditions including uniaxial tension and confined compression. The performance of the model is observed to be satisfactory. Furthermore, the superiority of ECDPM over three previously proposed constitutive models is demonstrated through comparisons with the results of a uniaxial tension-compression test and a virtual test.

关键词： damage plasticity model     plain concrete     cyclic loading     multiaxial loading conditions    

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Nonlinear cumulative damage model for multiaxial fatigue

SHANG De-guang, SUN Guo-qin, DENG Jing, YAN Chu-liang

《机械工程前沿（英文）》 2006年 第1卷 第3期   页码 265-269 doi: 10.1007/s11465-006-0035-x

摘要： On the basis of the continuum fatigue damage theory, a nonlinear uniaxial fatigue cumulative damage model is first proposed. In order to describe multiaxial fatigue damage characteristics, a nonlinear multiaxial fatigue cumulative damage model is developed based on the critical plane approach. The proposed model can consider the multiaxial fatigue limit, mean hydrostatic pressure and the unseparated characteristic for the damage variables and loading parameters. The recurrence formula of fatigue damage model was derived under multilevel loading, which is used to predict multiaxial fatigue life. The results showed that the proposed nonlinear multiaxial fatigue cumulative damage model is better than Miner s rule.
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Confining pressure effect on dynamic response of high rockfill dam

Xuexing CAO, Yunlong HE, Kun XIONG,

《结构与土木工程前沿（英文）》 2010年 第4卷 第1期   页码 116-126 doi: 10.1007/s11709-010-0014-5

摘要： Studies show that the dynamic properties of rockfill are strongly dependent on the confining pressure. Therefore, confining pressure effect has become a very important factor in the seismic analysis of high rockfill dam. The relationships of dynamic shear modulus versus dynamic shear strain and damping ratio versus dynamic shear strain had been improved to a certain degree on the basic of widely used Hardin-Drnevich constitutive model in this paper. Then a new model that could consider confining pressure effect has been established. Regression analysis was carried out of the dynamic triaxial experimental data of the damming materials in the Changheba hydropower station of Sichun Province, China. The results show that, the new model can fit the test data well under various confining pressures. A corresponding computational procedure was compiled and applied in the dynamic response analysis of the Changheba Dam. Comparing the calculation results between the new constitutive model and the ordinary Hardin-Drnevich model, it can be seen that the result is conservative to some extent without considering confining pressure effect.

关键词： confining pressure effect     high rockfill dam     dynamic response     Hardin-Drnevich constitutive model    

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钨合金的冲击拉伸行为及其本构和断裂判据的表述

张宝,丁淳彤,刘宝华,陈雪莲

《中国工程科学》 2003年 第5卷 第3期   页码 44-50

摘要：

利用飞轮式Hopkinson拉杆实验技术对钨质量分数为93% 的钨合金在-50～100℃温度范围、应变率ε=102～103s-1区间的动态拉伸性态进行了测试，提供了相应的σ-ε曲线和最大拉伸失效应变，并以此为依据建立了该合金动态拉伸行为的本构关系，提出了该合金受动载发生塑性失稳以致发生拉断的判据。利用断口分形分析理论，对试件拉伸断口微观特征所作的分析和对宏观力学性态实验所作的结论给予了有力的支持。

关键词： 动态拉伸本构模型     钨合金     断裂失效判据    

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Hypoplastic constitutive modeling of wetting deformation of weathered rockfill materials

Erich BAUER, Zhongzhi FU, Sihong LIU,

《结构与土木工程前沿（英文）》 2010年 第4卷 第1期   页码 78-91 doi: 10.1007/s11709-010-0011-8

摘要： The wetting deformation of weathered rockfill materials has been attracting growing attention from both engineers and scientists. The importance of realistic predictions of wetting deformations for high earth and rockfill dams is a strong motivation to establish a suitable constitutive model. Recently, the hypoplastic constitutive model by Gudehus and Bauer was extended by introducing solid hardness depending on the state of weathering. The extended model takes into account the influence of the current density, the effective stress state, the rate of deformation, and the time dependent process of degradation of the solid hardness. In the present paper, the performance of this model is evaluated by comparing numerical simulations with experiments obtained from a water sensitive rockfill material. In particular, triaxial compression paths and creep deformation under deviatoric stress states are considered. Finally, the constitutive model proposed is used to study the influence of a degradation of the solid hardness on the long term behavior of a hypothetical fill dam.

关键词： rockfill dams     weathered granular materials     hypoplasticity     solid hardness     creep     stress relaxation    

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Numerical modeling of nonlinear deformation of polymer composites based on hyperelastic constitutive

Qingsheng YANG, Fang XU

《机械工程前沿（英文）》 2009年 第4卷 第3期   页码 284-288 doi: 10.1007/s11465-009-0067-0

摘要： Fiber reinforced polymer (FRP) composites exhibit nonlinear and hyperelastic characteristics under finite deformation. This paper investigates the macroscopic hyperelastic behavior of fiber reinforced polymer composites using a micromechanical model and finite deformation theory based on the hyperelastic constitutive law. The local stress and deformation of a representative volume element are calculated by the nonlinear finite element method. Then, an averaging procedure is used to find the homogenized stress and strain, and the macroscopic stress-strain curves are obtained. Numerical examples are given to demonstrate hyperelastic behavior and deformation of the composites, and the effects of the distribution pattern of fibers are also investigated to model the mechanical behavior of FRP composites.

关键词： composites     hyperelastic     finite deformation     homogenization     micromechanics    

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Multiscale computation on feedforward neural network and recurrent neural network

Bin LI, Xiaoying ZHUANG

《结构与土木工程前沿（英文）》 2020年 第14卷 第6期   页码 1285-1298 doi: 10.1007/s11709-020-0691-7

摘要： Homogenization methods can be used to predict the effective macroscopic properties of materials that are heterogenous at micro- or fine-scale. Among existing methods for homogenization, computational homogenization is widely used in multiscale analyses of structures and materials. Conventional computational homogenization suffers from long computing times, which substantially limits its application in analyzing engineering problems. The neural networks can be used to construct fully decoupled approaches in nonlinear multiscale methods by mapping macroscopic loading and microscopic response. Computational homogenization methods for nonlinear material and implementation of offline multiscale computation are studied to generate data set. This article intends to model the multiscale constitution using feedforward neural network (FNN) and recurrent neural network (RNN), and appropriate set of loading paths are selected to effectively predict the materials behavior along unknown paths. Applications to two-dimensional multiscale analysis are tested and discussed in detail.

关键词： multiscale method     constitutive model     feedforward neural network     recurrent neural network    

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An efficient two-stage approach for structural damage detection using meta-heuristic algorithms and groupmethod of data handling surrogate model

Hamed FATHNEJAT, Behrouz AHMADI-NEDUSHAN

《结构与土木工程前沿（英文）》 2020年 第14卷 第4期   页码 907-929 doi: 10.1007/s11709-020-0628-1

摘要： In this study, the performance of an efficient two-stage methodology which is applied in a damage detection system using a surrogate model of the structure has been investigated. In the first stage, in order to locate the damage accurately, the performance of the modal strain energy based index for using different numbers of natural mode shapes has been evaluated using the confusion matrix. In the second stage, to estimate the damage extent, the sensitivity of most used modal properties due to damage, such as natural frequency and flexibility matrix is compared with the mean normalized modal strain energy (MNMSE) of suspected damaged elements. Moreover, a modal property change vector is evaluated using the group method of data handling (GMDH) network as a surrogate model during damage extent estimation by optimization algorithm; in this part of methodology, the performance of the three popular optimization algorithms including particle swarm optimization (PSO), bat algorithm (BA), and colliding bodies optimization (CBO) is examined and in this regard, root mean square deviation ( ) based on the modal property change vector has been proposed as an objective function. Furthermore, the effect of noise in the measurement of structural responses by the sensors has also been studied. Finally, in order to achieve the most generalized neural network as a surrogate model, GMDH performance is compared with a properly trained cascade feed-forward neural network (CFNN) with log-sigmoid hidden layer transfer function. The results indicate that the accuracy of damage extent estimation is acceptable in the case of integration of PSO and MNMSE. Moreover, the GMDH model is also more efficient and mimics the behavior of the structure slightly better than CFNN model.

关键词： two-stage method     modal strain energy     surrogate model     GMDH     optimization damage detection    

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Damage mechanism and evaluation model of compressor impeller remanufacturing blanks: A review

Haiyang LU, Yanle LI, Fangyi LI, Xingyi ZHANG, Chuanwei ZHANG, Jiyu DU, Zhen LI, Xueju RAN, Jianfeng LI, Weiqiang WANG

《机械工程前沿（英文）》 2019年 第14卷 第4期   页码 402-411 doi: 10.1007/s11465-019-0548-8

摘要： The theoretical and technological achievements in the damage mechanism and evaluation model obtained through the national basic research program “Key Fundamental Scientific Problems on Mechanical Equipment Remanufacturing” are reviewed in this work. Large centrifugal compressor impeller blanks were used as the study object. The materials of the blanks were FV520B and KMN. The mechanism and evaluation model of ultra-high cycle fatigue, erosion wear, and corrosion damage were studied via theoretical calculation, finite element simulation, and experimentation. For ultra-high cycle fatigue damage, the characteristics of ultra-high cycle fatigue of the impeller material were clarified, and prediction models of ultra-high cycle fatigue strength were established. A residual life evaluation technique based on the “ - - ” (where was the nonlinear parameter, was the Vickers hardness, and was the fatigue life) double criterion method was proposed. For erosion wear, the flow field of gas-solid two-phase flow inside the impeller was simulated, and the erosion wear law was clarified. Two models for erosion rate and erosion depth calculation were established. For corrosion damage, the electrochemical and stress corrosion behaviors of the impeller material and welded joints in H S/CO environment were investigated. (critical stress intensity factor) and d /d (crack growth rate, where is the total crack length and is time) varied with H S concentration and temperature, and their variation laws were revealed. Through this research, the key scientific problems of the damage behavior and mechanism of remanufacturing objects in the multi-strength field and cross-scale were solved. The findings provide theoretical and evaluation model support for the analysis and evaluation of large centrifugal compressor impellers before remanufacturing.

关键词： remanufacturing     centrifugal compressor impeller     remanufacturing blank     damage mechanism     evaluation model    

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Static-based early-damage detection using symbolic data analysis and unsupervised learning methods

João Pedro SANTOS,Christian CREMONA,André D. ORCESI,Paulo SILVEIRA,Luis CALADO

《结构与土木工程前沿（英文）》 2015年 第9卷 第1期   页码 1-16 doi: 10.1007/s11709-014-0277-3

摘要： A large amount of researches and studies have been recently performed by applying statistical and machine learning techniques for vibration-based damage detection. However, the global character inherent to the limited number of modal properties issued from operational modal analysis may be not appropriate for early-damage, which has generally a local character. The present paper aims at detecting this type of damage by using static SHM data and by assuming that early-damage produces dead load redistribution. To achieve this objective a data driven strategy is proposed, consisting of the combination of advanced statistical and machine learning methods such as principal component analysis, symbolic data analysis and cluster analysis. From this analysis it was observed that, under the noise levels measured on site, the proposed strategy is able to automatically detect stiffness reduction in stay cables reaching at least 1%.

关键词： structural health monitoring     early-damage detection     principal component analysis     symbolic data     symbolic dissimilarity measures     cluster analysis     numerical model     damage simulations    

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标题 作者 时间 类型 操作

Damage-constitutive model for seawater coral concrete using different stirrup confinements subjected

期刊论文

Endochronic damage constitutive model for fully-graded aggregate mass concrete

SONG Yupu, WANG Huailiang

期刊论文

Development of a constitutive model for rockfills and similar granular materials based on the disturbed

Mehdi VEISKARAMI, Ali GHORBANI, Mohammadreza ALAVIPOUR

期刊论文

Cyclic behavior of prefabricated reinforced concrete frame with infill slit shear walls

Kui XIAO,Qilin ZHANG,Bin JIA

期刊论文

Unified description of sand behavior

Feng ZHANG, Bin YE, Guanlin YE

期刊论文

An enhanced damage plasticity model for predicting the cyclic behavior of plain concrete under multiaxial

Mohammad Reza AZADI KAKAVAND, Ertugrul TACIROGLU

期刊论文

Nonlinear cumulative damage model for multiaxial fatigue

SHANG De-guang, SUN Guo-qin, DENG Jing, YAN Chu-liang

期刊论文

Confining pressure effect on dynamic response of high rockfill dam

Xuexing CAO, Yunlong HE, Kun XIONG,

期刊论文

钨合金的冲击拉伸行为及其本构和断裂判据的表述

张宝,丁淳彤,刘宝华,陈雪莲

期刊论文

Hypoplastic constitutive modeling of wetting deformation of weathered rockfill materials

Erich BAUER, Zhongzhi FU, Sihong LIU,

期刊论文

Numerical modeling of nonlinear deformation of polymer composites based on hyperelastic constitutive

Qingsheng YANG, Fang XU

期刊论文

Multiscale computation on feedforward neural network and recurrent neural network

Bin LI, Xiaoying ZHUANG

期刊论文

An efficient two-stage approach for structural damage detection using meta-heuristic algorithms and groupmethod of data handling surrogate model

Hamed FATHNEJAT, Behrouz AHMADI-NEDUSHAN

期刊论文

Damage mechanism and evaluation model of compressor impeller remanufacturing blanks: A review

Haiyang LU, Yanle LI, Fangyi LI, Xingyi ZHANG, Chuanwei ZHANG, Jiyu DU, Zhen LI, Xueju RAN, Jianfeng LI, Weiqiang WANG

期刊论文

Static-based early-damage detection using symbolic data analysis and unsupervised learning methods

João Pedro SANTOS,Christian CREMONA,André D. ORCESI,Paulo SILVEIRA,Luis CALADO

期刊论文