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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 {2., Wuhan 430074,china.2.department of civil engineering,nanyang institute of {2.,nanyang 473004,china.3.department of Chemistry and Bioengineering,nanyang institute of {2.,nanyang 473004,china. School of civil engineering and Mechanics Huazhong University of Science and Technology Wuhan 430074 China department of civil {2. 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

Theoretical analysis of natural frequency of externally prestressed concrete beam based on rigidity correction

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Journal of Pharmaceutical Analysis 2009年第1期21卷 31-35页

作者： Hui-xia Xiong1,2. Yao-ting Zhang11.School of civil engineering & Mechanics, Huazhong University of Science and {2., Wuhan 430074, china.2.department of civil engineering, 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 {2. Nanyang Institute of Technology Nanyang 473004 China

A dynamic test on externally prestressed simply supported concrete beams separately with three typical types of tendon distributions was conducted. The results show that the natural frequencies of the beams increase with the increase in the prestressing force at the tensioning stage, and the natural frequencies decrease after the cracks occur in the beams. Following the calculation formula of natural frequency of externally prestressed beam, which was reported in a literature, the natural frequencies of the experimental beams are calculated, and big errors are found between the test results and the calculated ones of natural frequency values. As a result, this paper has tried to adopt two methods to correct the rigidity parameter of the concrete beam in the formula for natural frequency calculation, and to use the corrected formula to calculate the frequencies of the experimental beams. The calculation results indicate a good consistency with the experimental ones, which verifies the feasibility of the corrected formula.

关键词： externally prestressed concrete beam natural frequency rigidity correction regression analysis

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 {2., Wuhan 430074 2.department of Chemistry and Bioengineering,nanyang institute of {2.,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

Bipolar charged aerosol agglomeration and collection by a two-zone agglomerator

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Journal of Environmental Sciences 2001年第3期13卷 276-279页

作者： XIANG Xiao dong 1, CHEN Bao zhi 1, COLBECK I 2.(1. School of Resource and civil engineering, Northeastern University, Shenyang 110006,{2. 2. institute for Environmental Research, department of Biological and Chemical Sciences, University of Es School of Resource and civil engineering Northeastern University Shenyang 110006 China.

In older to collect fine particles more efficiently, a new-type electrostatic agglomerator with two zones was developed. The distinguishing feature of this electrostatic agglomerator is that the particles are bipolarly charged and coagulated in the same alternating electric field simultaneously. The silica flour with 2.fun mass median diameter and the smoke from burning wood powder were used as test aerosol. The comparison experimental results have shown that when the mean electric field is 4 kV/cm the collection efficiency of the new electrostatic agglomerator was 98.2. for silica flour and 67.4% for wood powder smoke, Under the same experimental condition. the collection efficiency of the electrostatic agglomerator with three zones was 97.4% for collecting silica flour and the collection efficiency of the electrostatic precipitator was 56.3% for wood powder smoke.

关键词： charged particle agglomeration alternating electric field electrostatic agglomerator (EA) electrostatic precipitator (ESP) collection efficiency

On three-dimensional geological modeling and visualization

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Science china.Earth Sciences 2004年第8期47卷 739-748页

作者： WU Qiang1 & XU Hua2.1. department of Resource Exploitation engineering,{2.University of Mining and technology, Beijing 100083,{2.2. Beijing institute of Petrochemical technology, Beijing 102.17, china 1. department of Resource Exploitation engineering China University of Mining and Technology 100083 Beijing China 2. Beijing institute of Petrochemical technology 102617 Beijing China

The technology of 3D geological modeling will bring about great changes in the methods of geological data acquiring, storing, processing and displaying. However, no perfect or convenient software systems have been developed up to now since the geologic data which re-flect geological entities bear the feature of diversity, uncertainty and complexity. Some supervoxel models, mathematical models of fault and geometrical models of fold have been contrived so as to show the space geometric configuration of the complicated geologic structures. The application-oriented system architecture for 3D geological modeling is established; and a novel design concept based on spatial data processing is also proposed with the technology of solid modeling as its core and the application of models as its objective. Theories and methods for 3D geological modeling will hopefully be enriched and developed. In the light of these theories and methods, a feature-based navigation visualization technique is also put forward in the paper. By integrating geo-database, graphics libraries and KBS with 3D dynamic simulation systems, geologists will be able to capture the partial characteristics and whole structure embodied in the geological data in a direct-viewing, figurative and accurate manner.

关键词： 3D geological modeling,geometrical model,system architecture,visualization

A new sequential learning algorithm for RBF neural networks

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Science china.Technological Sciences) 2004年第4期47卷 447-460页

作者： YANG Ge1, LV Jianhong1 & LIU Zhiyuan2.1. department of Power engineering, Southeast University, Nanjing 2.0096,{2.2. department of Power engineering, Nanjing institute of technology, Nanjing 2.0013, china 1. department of Power engineering Southeast University 210096 Nanjing China 2. department of Power engineering Nanjing Institute of Technology 210013 Nanjing China

Due to their inherent imperfections, it is hard to use the static neural networks for nonlinear time-varying process modeling and prediction, and the minimal resource allocation network (MRAN) is difficult to be realized for its too many regulation parameters. A new sequential learning algorithm for radial basis function (RBF) neural networks based on local projection named Local Projection Network (LPN) is proposed in this paper. The results of validation for several benchmark problems with the new algorithm show that the presented LPN not only has the same level as M-RAN in network size and precision of the outputs, but also has fewer regulation parameters and is more predictable.

关键词： radial basis functions, local projection network, minimal resource allocation network, learning algorithm.

Analysis on cohesive crack opening displacement considering the strain softening effect

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Science china.Physics,Mechanics & Astronomy) 2006年第1期49卷 88-101页

作者： WANG Limin1, XU Shilang2.& ZHAO Xiqiang3 1. Mechanics department, Shandong University of technology, Zibo 2.5049,{2.2. civil engineering department, Dalian University of technology, Dalian 11602.,{2.3. Mathematics department, Ocean University of{2. Qingdao 2.6071, china Mechanics department Shandong University of Technology Zibo 255049 China civil engineering {2. Dalian University of Technology Dalian 116024 China Mathematics department Ocean University of China Qingdao 266071 China

In order to investigate the crack propagation in quasi-brittle materials like rock, ceramic and concrete, Hillerborg and his co-researchers abstracted the fracture process zone in front of a stress free crack in terms of a “fictitious crack zone”. On the fictitious crack zone, cohesive stresses distribute following a given softening relationship of stress vs. crack opening. Based on the polynomial or power series expression of cohesive crack opening displacement, the relationship of the cohesive stress vs. the crack opening displacement is established using elastic theory and integral equation, and some unknown physics variables are obtained using variation approach. The calculation results gained in this paper are close to the experimentally test ones.

关键词： cohesive crack, softening, dissipation work, variation approach.

Allocation of power generating and shipping of Hanjiang upstream cascade

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Progress in Natural Science:Materials International 2005年第8期15卷 733-741页

作者： LIU Junping1* and CHANG Mingqi 2.3(1. School of civil engineering and Architecture, Zhejiang University of {2., Hangzhou 310014, china.2. institute of Water Resources & Hydroelectric engineering, Xi'an University of {2., Xi'an 710048, china.3. Shanxi institute of Water Resources, Taiyuan 030001, china. School of civil engineering and Architecture Zhejiang University of Technology Hangzhou 310014 China institute of Water Resources and Hydroelectric engineering Xi'an University of Technology Xi'an 710048 China Shanxi institute of Water Resources Taiyuan 030001 China

The optimal model and simulating model of the Hanjiang cascade reservoirs operation with one day as its calculating period are established to coordinate the contradictions between power generating and shipping. The optimal model is solved by progressive optimality algorithm method adopting the theory of large system decomposing and coordinating. By analyzing the water allocation results obtained from six schemes, which are two cascades, four cascades and seven cascades joint operation considering shipping or not, the contradiction degree between power generating and shipping is investigated and some joint operation schemes are proposed.

关键词： cascade power generating contradiction shipping optimal operation.

A land surface model incorporated with soil freeze/thaw and its application in GAME/Tibet

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Science china.Earth Sciences 2006年第12期49卷 1311-1322页

作者： HU Heping1, YE Baisheng2. ZHOU Yuhua3 & TIAN Fuqiang1 1. department of Hydraulic engineering, Tsinghua University, Beijing 100084,{2.2. Cold and Arid Regions Environmental and engineering Research institute, Chinese Academy of Sciences, Lanzhou 730000,{2.3. department of civil engineering, Massachusetts institute of technology, USA 1. department of Hydraulic engineering Tsinghua University Beijing 100084 China 2. Cold and Arid Regions Environmental and engineering Research institute Chinese Academy of Sciences Lanzhou 730000 China 3. department of civil {2. Massachusetts Institute of Technology USA

Land surface process is of great importance in global climate change, moisture and heat exchange in the interface of the earth and atmosphere, human impacts on the environment and eco- system, etc. Soil freeze/thaw plays an important role in cold land surface processes. In this work the diurnal freeze/thaw effects on energy partition in the context of GAME/Tibet are studied. A sophisti- cated land surface model is developed, the particular aspect of which is its physical consideration of soil freeze/thaw and vapor flux. The simultaneous water and heat transfer soil sub-model not only reflects the water flow from unfrozen zone to frozen fringe in freezing/thawing soil, but also demon- strates the change of moisture and temperature field induced by vapor flux from high temperature zone to low temperature zone, which makes the model applicable for various circumstances. The modified Picard numerical method is employed to help with the water balance and convergence of the numerical scheme. Finally, the model is applied to analyze the diurnal energy and water cycle char- acteristics over the Tibetan Plateau using the Game/Tibet datasets observed in May and July of 1998. Heat and energy transfer simulation shows that: (i) There exists a negative feedback mechanism between soil freeze/thaw and soil temperature/ground heat flux; (ii) during freezing period all three heat fluxes do not vary apparently, in spite of the fact that the negative soil temperature is higher than that not considering soil freeze; (iii) during thawing period, ground heat flux increases, and sensible heat flux decreases, but latent heat flux does not change much; and (iv) during freezing period, soil temperature decreases, though ground heat flux increases.

关键词： land surface model,soil freeze/thaw,GAME/Tibet,simultaneous liquid,vapor and heat transfer.