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Intelligent direct analysis of physical and mechanical parameters of tunnel surrounding rock based on adaptive immunity algorithm and BP neural network

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Journal of Pharmaceutical Analysis 2009年第1期21卷 22-30页

作者： Xiao-rui Wang1,2, Yuan-han Wang1, Xiao-feng Jia31.School of civil engineering and Mechanics,Huazhong University of Science and technology, Wuhan 430074,china.2.department of civil engineering,nanyang institute of technology,nanyang 473004,china.3.department of Chemistry and Bioengineering,nanyang institute of technology,nanyang 473004,china. School of civil engineering and Mechanics Huazhong University of Science and Technology Wuhan 430074 China department of civil engineering Nanyang Institute of Technology Nanyang 473004 China department of Chemistry and Bioengineering Nanyang Institute of Technology Nanyang 473004 China

Because of complexity and non-predictability of the tunnel surrounding rock, the problem with the determination of the physical and mechanical parameters of the surrounding rock has become a main obstacle to theoretical research and numerical analysis in tunnel engineering. During design, it is a frequent practice, therefore, to give recommended values by analog based on experience. It is a key point in current research to make use of the displacement back analytic method to comparatively accurately determine the parameters of the surrounding rock whereas artificial intelligence possesses an exceptionally strong capability of identifying, expressing and coping with such complex non-linear relationships. The parameters can be verified by searching the optimal network structure, using back analysis on measured data to search optimal parameters and performing direct computation of the obtained results. In the current paper, the direct analysis is performed with the biological emulation system and the software of Fast Lagrangian Analysis of Continua (FLAC3D. The high non-linearity, network reasoning and coupling ability of the neural network are employed. The output vector required of the training of the neural network is obtained with the numerical analysis software. And the overall space search is conducted by employing the Adaptive Immunity Algorithm. As a result, we are able to avoid the shortcoming that multiple parameters and optimized parameters are easy to fall into a local extremum. At the same time, the computing speed and efficiency are increased as well. Further, in the paper satisfactory conclusions are arrived at through the intelligent direct-back analysis on the monitored and measured data at the Erdaoya tunneling project. The results show that the physical and mechanical parameters obtained by the intelligent direct-back analysis proposed in the current paper have effectively improved the recommended values in the original prospecting data. This is of p

关键词： adaptive immunity algorithm BP neural network physical and mechanical parameters surrounding rock direct-back analysis

Assessing a soft twin tunneling numerical model using field data

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Journal of Pharmaceutical Analysis 2009年第1期21卷 36-41页

作者： Ke-shuan Ma1,2,Lie-yun Ding11. School of civil engineering and Mechanics,Hubei Key Laboratory of Control Structure, Huazhong University of Science & technology, Wuhan 430074, china.2. department of civil engineering, nanyang institute of technology, nanyang 473004, china. School of civil engineering and Mechanics Hubei Key Laboratory of Control Structure Huazhong University of Science and Technology Wuhan 430074 China department of civil engineering Nanyang Institute of Technology Nanyang 473004 China

Using a five-floor building affected by the Yangtze River highway tunnels in Wuhan as the engineering background, we have constructed a free-field model and a coupled model to study the soil, lining, foundations and upper structure, and analyze the rules of movements of building foundation and ground induced by single tunnel and twin tunnel excavation with the Finite Element Analysis method. It is shown that for the coupled model, the longitudinal displacement of each foundation increases slowly when the tunnel face gets close to the foundation section and then increases fast when the tunnel face moves away from the foundation during the single and twin tunneling. For a single tunnel, the surface settlements are overestimated by the free-field and coupled tunnel. This might be crucial in urban areas. Regarding the maximum settlements and the width of the settlement trough, the difference between the free-field model and the coupled model is quite obvious. This comparison with the field measurement value reveals that the coupled model seems to be superior to the free-field model. These results are of instructive significance for design and excavation.

关键词： finite element analysis three-dimensional slurry shield tunneling building settlement

Intelligent optimization of the structure of the large section highway tunnel based on improved immune genetic algorithm

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Journal of Pharmaceutical Analysis 2009年第3期21卷 163-166页

作者： Hai-tao Bo1,Xiao-feng Jia2,Xiao-rui Wang11.School of civil engineering and Mechanics,Huazhong University of Science and technology, Wuhan 430074 2.department of Chemistry and Bioengineering,nanyang institute of technology,nanyang 473004,china. School of civil engineering and Mechanics Huazhong University of Science and Technology Wuhan 430074 China department of Chemistry and Bioengineering Nanyang Institute of Technology Nanyang 473004 China

As in the building of deep buried long tunnels,there are complicated conditions such as great deformation,high stress,multi-variables,high non-linearity and so on,the algorithm for structure optimization and its application in tunnel engineering are still in the starting stage. Along with the rapid development of highways across the country,it has become a very urgent task to be tackled to carry out the optimization design of the structure of the section of the tunnel to lessen excavation workload and to reinforce the support. Artificial intelligence demonstrates an extremely strong capability of identifying,expressing and disposing such kind of multiple variables and complicated non-linear relations. In this paper,a comprehensive consideration of the strategy of the selection and updating of the concentration and adaptability of the immune algorithm is made to replace the selection mode in the original genetic algorithm which depends simply on the adaptability value. Such an algorithm has the advantages of both the immune algorithm and the genetic algorithm,thus serving the purpose of not only enhancing the individual adaptability but maintaining the individual diversity as well. By use of the identifying function of the antigen memory,the global search capability of the immune genetic algorithm is raised,thereby avoiding the occurrence of the premature phenomenon. By optimizing the structure of the section of the Huayuan tunnel,the current excavation area and support design are adjusted. A conclusion with applicable value is arrived at. At a higher computational speed and a higher efficiency,the current method is verified to have advantages in the optimization computation of the tunnel project. This also suggests that the application of the immune genetic algorithm has a practical significance to the stability assessment and informationization design of the wall rock of the tunnel.

关键词： immune genetic algorithm tunnel super-large section optimization

Influence of Calcium Sulfate State and Fineness of Cement on Hydration of Portland Cements Using Electrical Measurement

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Journal of Wuhan University of technology(Materials Science) 2006年第4期21卷 141-145页

作者：魏小胜 department of civil engineering Huazhong University of Science and Technology Wuhan 430074 China

The influence of calcium sulfate state and fineness of cement on hydration of Portland cement was studied using electrical resistivity measurement. The bulk resistivity curve of the paste from the abnormal cement mainly with hemihydrate had a characteristic abnormal peak and rapid increase in early period. The resistivity measurement technique can be used to discriminate abnormal setting. For normal cement with gypsum, the increase in fineness of the Portland cement decreases the minimum resistivhy due to a higher ionic concentration and increases the 24 hour resistivity due to a reduction in macroscopic pore size. The setting time, compressive strength, pore structure of pastes made from different cements were carried out to compare the influence of water to cement ratio, calcium sulfate state and fineness. It is found that the electrical and mechanical properties are strongly affected by the initial porosity, the presence of hemihydrate or gypsum, and the fineness of cement.

关键词： false setting electrical resistivity fineness hydration

The Compatibility of Polycarboxylate-Type Superplasticizers with Cement

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Journal of Wuhan University of technology(Materials Science) 2005年第3期20卷 95-98页

作者：李崇智 department of civil engineering Beijing Institute of Civil Engineering and Architecture

Four polycarboxylate- type （ PC ） superplasticizers of different functional groups were used ; their dispersing and retaining behaviors were analyzed through ZETA potential measurement, mini-slump test of cement paste and performance test of concrete. The experimental results show that the dispersing and flow-retaining ability of PC was determined by two factors of anionic groups and nonionic groups ： the density of anionic groups - COO^- or - SO3^- acted on the electronic repulsive force. and the length and proportion of nonionic graft groups of PEO in PC chemical stracture affected the steric effect. The compatibility between PC superplasticizers and cement mainly depended on the type of PEO groups ; furtlwrmore, adding mineral powders is good to the compatibility for high performance concretes （ HPCs ）.

关键词： PC superplasticizers cement compatibility

A two-dimensional study on natural convection and heat transfer in the enclosure with heat transfer and radiation coupled in natural convection

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Science china.Technological Sciences) 2010年第4期53卷 991-999页

作者： ZHAN NaiYan1,2,YANG Mo1 & XU PeiWei2 1 College of Power engineering,University of Shanghai for Science and technology,Shanghiai 200093,china.2.department of Environmental engineering,Jilin Architectural and civil engineering institute,Changchun 130021,china 1. College of Power engineering University of Shanghai for Science and Technology Shanghiai 200093 China2. Department of Environmental Engineering Jilin Architectural and Civil Engineering Institute Changchun 130021 China

Numerical investigation using SIMPLE algorithm with QUICK scheme for natural convection and heat transfer in the enclosure bounded by a solid wall and with heat transfer and radiation coupled in natural convection has been *** various parameters are:Rayleigh number(from 103 to 105),dimensionless conductivity of bounding wall(from 0 to 100),dimensionless wall thickness(from 0 to 0.6) and radiation emissivity of all surfaces(from 0 to 1).The results suggest that flow and heat transfer are influenced by *** is a dominant action on flow and heat *** increase of the thermal conductivity of wall,flow and heat transfer turn *** temperature distribution changes *** the thermal conductivity of wall is over a certain critical number,the increasing trend of flow and heat transfer may *** increase of enclosure wall thickness,flow and heat transfer turn *** the enclosure wall thickness is over a certain critical number,the flow and heat transfer will turn slow.

关键词： conduction natural convection radiation couple numerical simulation

Numerical Simulation and Assessment of Self-induced Tensile Stresses in Steel Ring Restrained Concrete

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Journal of Wuhan University of technology(Materials Science) 2010年第3期25卷 530-533页

作者：马新伟 department of civil engineering Harbin Institute of Technology

For a better understanding of the strains and stresses,numerical simulation was conducted by using ANSYS under the assumption of absolute bond between the steel and *** results show that the stresses and strains in such concrete and steel rings are uneven;the curves of strains and stresses change gradually around the *** ease numerical computation,the mechanical system was simplified under the assumptions of synchronous deformation and uniform strains and *** results of the numerical simulation and simplified stress calculation can match almost *** means that the simplified mechanical model can be used in stress and visco-elastic behavior quantification.

关键词： restrained shrinkage numerical simulation model simplification

Conservation laws for mechanical systems with unilateral holonomic constraints

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Progress in Natural Science:Materials International 2004年第1期14卷 56-60页

作者： ZHANG Yi*(department of civil engineering, University of Science and technology of Suzhou, Suzhou 215011, china. Univ Sci & Technol Suzhou Dept Civil Engn Suzhou 215011 Peoples R China

A general approach to the construction of conservation laws for mechanical systems with unilateral holonomic constraints by finding corresponding integrating factors is presented. The definition of integrating factors for the Routh equations of motion of the systems is given, and the necessary conditions for the existence of conserved quantities of the unilateral holonomic constraint systems are studied in detail. The conservation theorem and its inverse for the systems are established, and an example is given to illustrate the application of the results.

关键词： unilateral holonomic constraint integrating factor conservation theorem Killing equation

Analytical theory of flexural behavior of concrete beam reinforced with textile-combined steel

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Science china.Technological Sciences) 2010年第6期53卷 1700-1710页

作者： XU ShiLang & YIN ShiPing department of civil engineering,Dalian University of technology,Dalian 116024,china 1. department of civil engineering Dalian University of Technology Dalian 116024 China

Textile-reinforced concrete (TRC) is a new high performance cementitious composite material,which not only has superior corrosion resistance but also can effectively limit the development of concrete cracks and make the crack width and spacing of concrete become ***,due to the brittle feature of fiber materials,the TRC structural member has no distinct failure symptom when it arrives at its ultimate *** the same time,ordinary reinforced concrete (RC) elements have large dead weight and can not efficiently restrict the expansion of the main crack of structures because of the restriction of their special cover *** order to overcome the disadvantages of both the TRC and the RC,a new architecture reinforced with textile-combined steel is proposed in this study,making full use of the advantages of the above two *** cover concrete at the tension zone of an RC element is partially replaced with TRC and thus the steel reinforcements replaced with textiles are *** with the old one,the new structure has less dead weight and has the merits of service safety and good *** flexural development process of the proper beam with this new structure is investigated in this paper and based on the plane section assumption,analytical equations are derived by using nonlinear analysis theory,including the load-carrying capacity at different stages and moment-curvature relationship and mid-span deflection during the entire loading *** between the calculated and the experimental results reveals satisfactory agreement and thus verifies the feasibility of the equations.

关键词： textile-reinforced concrete limiting the crack beam reinforced with textile-combined steel flexural behavior analytical theory