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Research in Cold and Arid Regions 2013年第4期5卷 488-497页

作者： Tao Wang GuoQing Zhou State Key Laboratory for Geomechanics and Deep Underground Engineering China University of Mining and Technology School of Architecture and Civil Engineering China University of Mining and Technology

To study the effect of uncertain factors on the temperature field of frozen soil, we propose a method to calculate the spatial average variance from just the point variance based on the local average theory of random fields. We model the heat transfer coefficient and specific heat capacity as spatially random fields instead of traditional random variables. An analysis for calculating the random temperature field of seasonal frozen soil is suggested by the Neumann stochastic finite element method, and here we provide the computational formulae of mathematical expectation, variance and variable coefficient. As shown in the calculation flow chart, the stochastic finite element calculation program for solving the random temperature field, as compiled by Matrix Laboratory （MATLAB） sottware, can directly output the statistical results of the temperature field of frozen soil. An example is presented to demonstrate the random effects from random field parameters, and the feasibility of the proposed approach is proven by compar- ing these results with the results derived when the random parameters are only modeled as random variables. The results show that the Neumann stochastic finite element method can efficiently solve the problem of random temperature fields of frozen soil based on random field theory, and it can reduce the variability of calculation results when the random parameters are modeled as spatial- ly random fields.

关键词： fi'ozen soil Neumann expansion stochastic finite element method random temperature field

STRUCTURE RELIABILITY ANALYSIS BASED ON stochastic finite element method

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STRUCTURE RELIABILITY ANALYSIS BASED ON STOCHASTIC FINITE EL...

Deterministic and probabilistic analysis of great-depth braced excavations:A 32 m excavation case study in Paris

The International Symposium on Innovation & Sustainability of Structures in Civil Engineering

作者： Jun Zhao Xia Cao and Linzhi Jin Department of Civil Engineering Guilin University of Technology Guilin 541004 China College of Civil Engineering Guangxi University Nanning 530004 China

＜正＞Based on the stochastic finite element method （SFEM） and the structural reliability theory, a calculate model of simulated beam is proposed in this Paper. Software for calculation based on SFEM has been developed to evaluate the reliability of beam. It can make sure of the load effect of beam units, and then the reliability of arbitrary section of the beam can be calculated The result is logical and is almost inosculated with the experimental data. It would be significant in the safety control of a reinforced concrete structure.

关键词： stochastic finite element method structural reliability.

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第5期16卷 1505-1521页

作者： Tingting Zhang Julien Baroth Daniel Dias Khadija Nejjar Université Grenoble Alpes CNRSGrenoble INP3SRGrenoble38000France Antea Group Antony92160France School of Automotive and Transportation Engineering Hefei University of TechnologyHefei23009China Terrasol 42-52 Quai de la RapéeParis75012France

The Fort d’Issy-Vanves-Clamart(FIVC)braced excavation in France is analyzed to provide insights into the geotechnical serviceability assessment of excavations at great depth within deterministic and probabilistic *** FIVC excavation is excavated at 32 m below the ground surface in Parisian sedimentary basin and a plane-strain finite element analysis is implemented to examine the wall deflections and ground surface settlements.A stochastic finite element method based on the polynomial chaos Kriging metamodel(MSFEM)is then proposed for the probabilistic *** with field measurements and former studies are carried *** academic cases are then conducted to investigate the great-depth excavation stability regarding the maximum horizontal wall deflection and maximum ground surface *** results indicate that the proposed MSFEM is effective for probabilistic analyses and can provide useful insights for the excavation design and construction.A sensitivity analysis for seven considered random parameters is then *** soil friction angle at the excavation bottom layer is the most significant one for *** soil-wall interaction effects on the excavation stability are also given.

关键词： Braced deep excavation Soil-wall interaction stochastic finite element method Horizontal wall deflection Settlement Failure probability

RELIABILITY OF ELASTO-PLASTIC STRUCTURE USING finite element method

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Acta Mechanica Sinica 2002年第1期18卷 66-81页

作者：刘宁邓汉忠卓家寿 College of Civil Engineering Hohai University Nanjing China 210098 Department of Civil Engineering The Hong Kong University of Science and Technology Hong Kong China

A solution of probabilistic FEM for elastic-plastic materials is presented based on the incremental theory of plasticity and a modified initial stress method. The formulations are deduced through a direct differentiation scheme. Partial differentiation of displacement, stress and the performance function can be iteratively performed with the computation of the mean values of displacement and stress. The presented method enjoys the efficiency of both the perturbation method and the finite difference method, but avoids the approximation during the partial differentiation calculation. In order to improve the efficiency, the adjoint vector method is introduced to calculate the differentiation of stress and displacement with respect to random variables. In addition, a time-saving computational method for reliability index of elastic-plastic materials is suggested based upon the advanced First Order Second Moment (FOSM) and by the usage of Taylor expansion for displacement. The suggested method is also applicable to 3-D cases.

关键词： stochastic finite element method elastic-plastic problem FOSM structural reliability

A Discussion on Two stochastic Elliptic Modeling Strategies

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Communications in Computational Physics 2012年第3期11卷 775-796页

作者： Xiaoliang Wan Department of Mathematics and Center for Computation and Technology Louisiana State UniversityBaton RougeLA 70803USA

Based on the study of two commonly used stochastic elliptic models:I:−∇·(a(x,w)·∇u(x,w))=f(x)and II:−∇·(a(x,w)⋄∇u(x,w))=f(x),we constructed a new stochastic elliptic model III:−∇·(a^(−1))^(⋄(−1))⋄∇u(x,w)=f(x),in[20].The difference between models I and II is twofold:a scaling factor induced by the way of applying theWick product and the regularization induced by theWick product ***[20],we showed that model III has the same scaling factor as model *** this paper we present a detailed discussion about the difference between models I and III with respect to the two characteristic parameters of the random coefficient,i.e.,the standard deviation s and the correlation length *** results are presented for both one-and twodimensional cases.

关键词： Wiener chaos stochastic PDE stochastic modeling stochastic finite element method

Effects of Crack Opening Angle and External Loads on Reliability of Welded Pipe with Circumferential Crack

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Journal of Shanghai Jiaotong university(Science) 2011年第3期16卷 368-371页

作者：何柏林于影霞霍立兴张玉凤 School of Mechatronics & Electrical Engineering East China Jiaotong University College of Material Science and Engineering Tianjin University

The reliability of welded pressure pipe with circumferential surface crack was calculated by using 3D stochastic finite element *** method has overcome the shortcomings of conservative results in safety assessment with deterministic fracture mechanics *** calculation of reliability was based on 3D elasticplastic stochastic finite element program which was developed by *** effects of variables such as fracture toughness,bending moment and depth of the circumferential surface crack on the structure reliability were also *** calculation results indicate that the crack opening angle has certain effect on the reliability of the welded *** the mean value of bending moment is 10kN·m,with the crack opening angle increasing from 30°to 180°,the failure probability of the welded pipe changes from 3.8379×10-8to 3.6943×*** the mean value of bending moment is 15kN·m,with the crack opening angle increasing from 30°to 180°,the failure probability of the welded pipe changes from 3.986 5×10-6to 1.936 7×*** bending moment has great effect on the reliability of the welded *** the mean value of moment is changed from 10 to 15 kN·m,the failure probability of the welded pipe increases dramatically for the same circumferential crack opening *** of changing of moment,the pipe has higher reliability if the crack opening angle is less than 60°.The method has put forward a new way for safety assessment of welded pipe with circumferential surface crack.

关键词： welded pipe circumferential surface crack stochastic finite element method reliability safety assessment

Fiber Concrete under Temperature Drop Load with stochastic FEM

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Journal of Shanghai Jiaotong university(Science) 2008年第2期13卷 161-165页

作者：齐锋张文金 School of Landscape Architecture and Art Zhejiang Forestry University

Plain concrete plate and fiber concrete plate subjected to temperature drop load were analyzed on stochastic finite element method (FEM).It is found that fibers can enhance concrete ability to resist tem- perature drop load for improving concrete's fracture energy and deferring the crack *** is found for concrete not to improve apparently its tensile strength and fracture energy is recommended to be its appraisal parameter.

关键词： fiber concrete stochastic finite element method temperature drop load

Effect of strength matching on the reliability of welded pipe with circumferential surface crack

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China Welding 2004年第2期13卷 106-110页

作者：何柏林于影霞霍立兴张玉凤 East China Jiaotong University Nanchang 330013 Tianjin University Tianjin 300072

For different strength matching, the reliability index and failure probability of welded pressure pipe with circumferential surface crack were calculated using three dimensional stochastic finite element method. This method has overcome the shortcomings of conservative results in safety assessment with deterministic fracture mechanics method. The effects of external moment and the depth of the circumferential surface crack (a) on the reliability of pressure pipe were also calculated and discussed. The calculation results indicate that the strength matching has certain effect on the reliability of the welded pressure pipe with circumferential surface crack. The failure probability of welded pressure pipe with high strength matching is lower than that with low strength matching at the same conditions. The effects of strength matching on the failure probability and reliability index increased by adding external moment (M) and the depth of the circumferential surface crack (a).

关键词： welded pressure pipe reliability crack strength matching stochastic finite element method

Static Force Reliability Analysis of Truss Structure with Piezoelectric Patches Affixed to Its Surface

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Chinese Journal of Aeronautics 2009年第1期22卷 22-31页

作者：安海安伟光哈尔滨工程大学航天工程系

For the truss structure composed of active-elements with piezoelectric patches affixed to its surface,taking the mechani-cal-electric coupling effect under the action of electric loads and mechanical loads into consideration,the finite element model for static force analysis is established by using the theory of mechanics. The failure mechanism of piezoelectric elements is discussed and the failure criteria of piezoelectric elements are proposed. The expression of safety margins for the element of piezoelec...

关键词： piezoelectric truss structure piezoelectric patch mechanical-electric coupling safety margin stochastic finite element method structural reliability theory

Probabilistic durability assessment approach of deteriorating RC bridges

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Journal of Southeast University(English Edition) 2011年第1期27卷 70-76页

作者：朱劲松高嫦娥天津大学建筑工程学院天津300072 天津大学滨海土木工程结构与安全教育部重点实验室天津300072

A stochastic finite element computational methodology for probabilistic durability assessment of deteriorating reinforced concrete（RC） bridges by considering the time-and space-dependent variabilities is ***,finite element analysis with a smeared cracking approach is *** time-dependent bond-slip relationship between steel and concrete,and the stress-strain relationship of corroded steel bars are ***,a stochastic finite element-based computational framework for reliability assessment of deteriorating RC bridges is *** spatial and temporal variability of several parameters affecting the reliability of RC bridges is *** on the data reported by several researchers and from field investigations,the Monte Carlo simulation is used to account for the uncertainties in various parameters,including local and general corrosion in rebars,concrete cover depth,surface chloride concentration,chloride diffusion coefficient,and corrosion ***,the proposed probabilistic durability assessment approach and framework are applied to evaluate the time-dependent reliability of a girder of a RC bridge located on the Tianjin Binhai New Area in China.

关键词： stochastic finite element method space-dependent reliability time-dependent reliability durability assessment concrete carbonation corrosion of rebars