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Environmental effects induced by excavation

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2008年第1期9卷 50-57页

作者： Yu-qi LI Jian ZHOU Kang-he xie Department of Civil Engineering Shanghai University Shanghai 200072 China Department of Geotechnical Engineering Tongji University Shanghai 200092 China Institute of Geotechnical Engineering Zhejiang University Hangzhou 310027 China

Based on 3D Biot’s consolidation theory and nonlinear Duncan-Chang’s model, a 3D FEM (finite element method) program is developed considering the coupling of groundwater seepage and soil skeleton deformation during excavation. The comparison between the analysis result considering the variation of water head difference and that without considering it shows that the porewater pressure distribution of the former is distinctly different from that of the latter and that the foundation pit de- formations of the former are larger than those of the latter, so that the result without considering the variation of water head dif- ference is unreliable. The distribution rules of soil horizontal and vertical displacements around the pit and excess porewater pressure are analyzed in detail in time and space, which is very significant for guiding underground engineering construction and ensuring environment safety around the pit.

关键词： Environmental effect Excavation Deformation Excess porewater pressure

Analysis of 1D consolidation with non-Darcian flow described by exponent and threshold gradient

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2010年第9期11卷 656-667页

作者： Chuan-xun LI Kang-he xie Kun WANG MOE Key Laboratory of Soft Soils and Geoenvironmental Engineering Zhejiang University Hangzhou 310027 China Department of Civil Engineering Jiangsu University Zhenjiang 212013 China

Numerous experiments have shown that the water flow in fine-grained soils can obey an exponential relationship at small gradients and a linear relationship when the hydraulic gradient exceeds a certain limit. Based on the non-Darcian flow described by exponent and threshold gradient, the theory of 1D consolidation is modified in this paper to consider a linear variation in the vertical total stress with depth and the effect of ramp loading. The numerical solutions were derived in detail by the finite difference method for excess pore water pressure and the average degree of consolidation. Finally, the influence of various parameters on consolidation behavior was investigated. The results show that the rate of consolidation is reduced when non-Darcian flow described by exponent and threshold gradient is adopted in the theory of 1D consolidation. As well the distribution of vertical total stress has a great influence on the dissipation of excess pore water pressure, either for pervious top and pervious bottom (PTPB) or for pervious top and impervious bottom (PTIB). For the case of PTIB, the distribution of vertical total stress in a foundation has a great influence on the rate of consolidation; however, for the case of PTPB, the rate of consolidation is independent of the distribution of vertical total stress. The rate of consolidation is dependent on the ratio of the thickness of a soil layer to the equivalent head of the final average vertical total stress; the greater the value of this ratio, the slower the rate of consolidation. Finally, an increase in construction time reduces the consolidation rate of a foundation. Thus, consolidation behavior of 1D consolidation with non-Darcian flow has been thoroughly acquainted in this paper.

关键词： 1D consolidation Non-Darcian flow Ramp loading Non-uniform distribution of vertical total stress

Nonlinear analytical solution for one-dimensional consolidation of soft soil under cyclic loading

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2006年第8期7卷 1358-1364页

作者： xie Kang-he QI Tian DONG Ya-qin Department of Civil Engineering Zhejiang University Hangzhou 310027 China

This paper presents an analytical solution for one-dimensional consolidation of soft soil under some common types of cyclic loading such as trapezoidal cyclic loading, based on the assumptions proposed by Davis and Raymond （1965） that the decrease in permeability is proportional to the decrease in compressibility during the consolidation process of the soil and that the distribution of initial effective stress is constant with depth the solution obtained, some diagrams are prepared and the It is verified by the existing analytical solutions in special cases. Using telex ant consolidation behavior is investigated.

关键词： One-dimensional (1 D) consolidation Nonlinear consolidation theory Analytical solution Cyclic loading

Damage on lining concrete in highway tunnels under combined sulfate and chloride attack

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Frontiers of Structural and Civil Engineering 2018年第3期12卷 331-340页

作者： Rongrong YIN Chenchen ZHANG Qing WU Baocheng LI he xie School of Architeture and Civil Engineering Jiangsu University of Science and Technology Zhenjiang 212003 China

The combined effect from sulfate and chloride is one of the important reasons to cause the damage of lining concrete in highway tunnels. To investigate the effect of chloride ions on the corrosion of lining concretes under sulfate attack, ultrasonic detecting, compression test and X-ray Diffraction （XRD） were performed on the concretes to obtain the ultrasonic velocity, corrosion thickness, compression strength and corrosion products. The ultrasonic results, compression strength and XRD patterns confirmed that the existence of chloride certainly depressed the corrosion damage on the lining concretes under sulfate attack, and the depressing effect increased with the content of chloride in the composite solution. The corrosion damage on the concretes experienced three stages independent of the composition of corrosive solution： initial slower enhancement on the strength, stabilization period and linear degradation period. The existence of chloride mainly affected the final degradation stage and obviously decreased the corrosion thickness.

关键词： lining concrete sulfate chloride compression ultrasonic

Steady-state response of a saturated half-space with an overlying dry layer subjected to a moving load

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2012年第1期13卷 33-43页

作者： An-feng HU Bo SUN Kang-he xie MOE Key Laboratory of Soft Soils and Geoenvironmental Engineering Zhejiang University Hangzhou 310058 China

In this paper,the steady-state response of a saturated half-space with an overlying dry layer subjected to a moving rectangular load is *** governing partial differential equations are solved using the Fourier *** solutions in time-space domain are expressed in terms of infinite Fourier type integrals,which can be evaluated only by numerical *** results show that the influence of a drained or undrained interface on the response is related to the permeability of the underlying saturated ***,the effect due to the upper dry layer is associated with the thickness of the layer.

关键词： Steady-state response Moving load Saturated half-space Overlying dry layer Fourier transform Drained orundrained interface

Review on the Progress and Issues in Liquid Tank Sloshing of Ships

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China Ocean Engineering 2023年第5期37卷 709-724页

作者： ZHANG Zhen TAO Ai-feng WU Qiao-rui xie Yong-he Key Laboratory of Ministry of Education for Coastal Disaster and Protection Hohai UniversityNanjing 210098China College of Harbor Coastal and Offshore EngineeringHohai UniversityNanjing 210098China College of Naval Architecture and Maritime Zhejiang Ocean UniversityZhoushan 316022China

With the development of large liquid cargo ships,liquid tank sloshing has gradually become a hot research topic in the area of shipping and ocean *** tank sloshing,characterized by strong nonlinearity and randomness,not only affects the stability of the ship but also generates a huge impact force on the wall of the *** further investigate liquid tank sloshing,a comprehensive review is given on the research process of the most focused subjects of liquid *** the existing research will help to identify issues in the current field and provide useful *** methods for investigating sloshing,the research progress and the situations worldwide are *** advantages and defects of experiments and numerical simulations are also *** problems which need to be explored in the future are subsequently proposed.

关键词： naval architecture and marine engineering liquid tank sloshing liquid cargo ship large deformation progress review

Consolidation solution for composite foundation considering a time-and depth-dependent stress increment along with three distribution patterns of soil permeability

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2011年第4期12卷 268-277页

作者： Meng-meng LU Kang-he xie Chuan-xun LI Kun WANG State Key Laboratory for Geomechanics and Deep Underground Engineering School of Meehanics & Civil Engineering China University of Mining & Technology Xuzhou 221008 China MOE Key Laboratory of Soft Soils and Geoenvironmental Engineering Zhejiang University Hangzhou 310058 China

In actual engineering practice,the stress increment within a composite foundation caused by external loads may vary simultaneously with depth and *** addition,column installation always leads to a decay of soil permeability towards the ***,almost none of the consolidation theories for composite foundation comprehensively consider these factors until *** this reason,a stress increment due to external loads changing simultaneously with time and depth was incorporated into the analysis,and three possible variation patterns of soil's horizontal permeability coefficient were considered to account for the detrimental influence of column *** three patterns included a constant distribution pattern(Pattern I),a linear distribution pattern(Pattern II),and a parabolic distribution pattern(Pattern III).Solutions were obtained for the average excess pore water pressures and the average degree of consolidation *** several special cases were discussed in detail based on the general solution ***,comparisons were made,and the results show that the present solution is the most general rigorous solution in the literature,and it can be broken down into a number of previous *** consolidation rate is accelerated with the increase in the value of the top to the bottom stress *** consolidation rate calculated by the solution for Pattern I is less than that for Pattern II,which in turn is less than that for Pattern III.

关键词： Consolidation Composite foundation Stone column Permeability Ramp load Disturbance effect

A Dynamic ID-Based Authenticated Group Key Exchange Protocol without Pairings

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Wuhan University Journal of Natural Sciences 2010年第3期15卷 255-260页

作者： xie Liyun he Mingxing School of Mathematics and Computer Engineering Xihua University Chengdu 610039 Sichuan China

So far, most of the proposed group key exchange （GKE） protocols do not consider the attack when the adversary reveals the parties＇ ephemeral private keys without their long-term private keys, so these GKE protocols are insecure on this attack. In this paper, for resisting above attack, we propose a dynamic authenticated group key exchange （AGKE） protocol in the ID-based setting. Different from previous ID-based protocols, our protocol does not utilize bilinear pairings, which makes it more efficient. At last, we analyze the security of the protocol in the cCK （enhanced Canetti-Krawczyk） security model.

关键词： group key exchange eCK security model without pairings

Shallow Donor Impurity Ground State in a GaAs/AlAs Spherical Quantum Dot within an Electric Field

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Communications in Theoretical Physics 2009年第10期52卷 710-714页

作者： YUAN Jian-Hui xie Wen-Fang he Li-Li Department of Physics College of Physics and Electronic Engineering Guangzhou University Guangzhou 510006 China

Using the configuration-integration methods （CI） [Phys. Rev. B 45 （1992） 19], we report the results of the Hydrogenie-impurity ground state in a GaAs/AIAs spherical quantum dot under an electric field. We discuss the variations of the binding energies of the Hydrogenic-impurity ground state as a function of the position of impurity D, the radius R of the quantum dot, and also as a function of electric field F. We find that the ground energy and binding energy of impurity placed anywhere depend strongly on the position of impurity. Also, electric field can largely change the Hydrogenic-impurity ground state only limiting to the big radius of quantum dot. And the differences in energy level and binding energy are observed from the center donor and off-center donor.

关键词： donor quantum dots binding energy electric field