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Model test of the tunnel subjected to high water pressure in Jinping Second Cascade Hydropower Station,China

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Science China(Technological Sciences) 2011年第S1期54卷 192-198页

作者： WANG JianXiu 1,2,FENG Bo 2,HU LiSheng 2,TIAN PuZhuo 2,SUI DongChang 2,TANG YiQun 1,2 &YANG Ping 1,2 1 Key Laboratory of geotechnical and Underground engineering of Ministry of Education,tongji university,{3.,China 2 department of geotechnical engineering,tongji university,{3.,China 1. Key Laboratory of geotechnical and Underground engineering of Ministry of Education Tongji University Shanghai 200092 China2. Department of Geotechnical Engineering Tongji University Shanghai 200092 China

In the area with high groundwater pressure,grout curtain is often adopted to reduce the water pressure on tunnel lining.A series of model tests for the diversion tunnel of the Jinping Second Cascade Hydropower Station,China,is designed to study the effect of grout *** impact of the thickness of grout curtain,permeability of grout curtain,internal water pressure and drainage inflow on the distribution of water pressure are *** results indicates that under un-drained condition,water pressure is equal to hydrostatic one no matter grout curtain is selected or not,water pressure under drained condition is far less than that of un-drained condition,drainage in tunnel can reduce tunnel water pressure *** same inflow,both increasing of thickness and decrease of hydraulic conductivity of grout curtain can reduce water pressure *** the same water pressure,the smaller inflow of grout curtain,the less volume of water to be *** impact of hydraulic conductivity of grout curtain is more obvious than that of *** increasing of internal water pressure,the water pressure of grout curtain increases too,and the water pressure increases nearly *** proposed thickness of grout curtain for the diversion tunnels is 16 m.

关键词： tunnel grout curtain water pressure model test

AN EXACT SYMPLECTIC SOLUTION FOR THE DYNAMIC ANALYSIS OF SHEAR DEFORMABLE ANTISYMMETRIC ANGLE-PLY LAMINATED PLATES

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Acta Mechanica Solida Sinica 1996年第3期9卷 263-273页

作者： Zou Guiping (department of engineering Mechanics,tongji university,{3.) tongji UNIV DEPT MECH ENGN SHANGHAI 200092 PEOPLES R CHINA

From the mixed variational principle, by the selection of the state variables and its dual variables, the Hamiltonian canonical equation for the dynamic analysis of shear deformable antisymmetric angle-ply laminated plates is derived, leading to the mathematical frame of symplectic geometry and algorithms, and the exact solution for the arbitrary boundary conditions is also derived by the adjoint orthonormalized symplectic expansion method. Numerical results are presented with the emphasis on the effects of length/thickness ratio, arbitrary boundary conditions, degrees of anisotropy, number of layers, ply-angles and the corrected coefficients of transverse shear.

关键词： Hamilton canonical equation symplectic free vibration analysis antisymmetric angle-ply laminated plates

Nonlinear constitutive law for ferroelectric/ferroelastic material and its finite element realization

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Science China(Physics,Mechanics & Astronomy) 2007年第1期50卷 70-86页

作者： LI YaoChen department of Aerospace engineering and Applied Mechanics,tongji university,{3.,China department of Aerospace engineering and Applied Mechanics Tongji UniversityShanghai 200092 China

The hysteresis phenomena of ferroelectric/ferroelastic material in polarization procedure are investigated. Some assumptions are presented based on the published experimental data. The electrical yielding criterion, mechanical yielding criterion and isotropic hardening model are established. The flow theory in incremental forms in polarization procedure is presented. The nonlinear constitutive law for electrical-mechanical coupling is proposed phenomenologically. Finally, the nonlinear constitutive law expressed in a form of matrices and vectors, which is immediately associated with finite element analysis, is formulated. In the example problem of a rectangular specimen subjected to a uniaxial electric field, the procedure from virgin state to fully polarized state is simulated. Afterward, a uniaxial compressive loading is applied to depolarizing the specimen. Results are in agreement with the experimental data.

关键词： ferroelectric/ferroelastic material constitutive law nonlinear finite element method.

Analytical solution for wave-induced response of isotropic poro-elastic seabed

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Science China(Technological Sciences) 2010年第10期53卷 2619-2629页

作者： ZHANG YongLi & LI Jie department of Building engineering, tongji university, {3., China 1. department of Building engineering Tongji University Shanghai 200092 China

By use of separation of variables,the governing equations describing the Biot consolidation model is firstly transformed into a complex coefficient linear homogeneous ordinary differential equation,and the general solution of the horizontal displacement of seabed is constructed by employing a complex wave number,thus,all the explicit analytical solutions of the Biot consolidation model are determined. By comparing with the experimental results and analytical solution of Yamamoto etc. and the analytical solution of Hsu and Jeng,the validity and superiority of the suggested solution are verified. After investigating the influence of seabed depth on the wave-induced response of isotropic poro-elastic seabed based on the present theory,it can be concluded that the influence depth of wave-induced hydrodynamic pressure in the seabed is equal to the wave length.

关键词： linear wave dynamic water pressure seabed analytical solution Biot consolidation model

Research on nonlinear constitutive relationship of permanent deformation in asphalt pavements

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Science China(Physics,Mechanics & Astronomy) 2006年第6期49卷 671-682页

作者： PENG Miaojuan1 & XU Zhihong2 1. department of Civil engineering,shanghai {3.,shanghai 200072,China 2. School of Transportation engineering,tongji university,shanghai 200092,China 1. department of Civil engineering Shanghai University Shanghai 200072 China 2. School of Transportation engineering Tongji University Shanghai 200092 China

To predict correctly the rut depths in asphalt pavements,a new nonlinear viscoelastic-elastoplastic constitutive model of permanent deformation in asphalt pave-ments is presented. The model combines a generalized Maxwell model with an elasto-plastic one. Then from the creep theory,the linear and nonlinear constitutive equations of the generalized Maxwell model are obtained. From the nonlinear finite element method for the rutting of the asphalt pavement,the rut depths of 4 asphalt-aggregate mixtures are obtained. And the results are compared with the ones from the finite element method by SHRP and the experiments by SWK/UN. The results in this paper are better than the ones by SHRP,and agree with the ones of the experiment by SWK/UN. This shows that the nonlinear viscoelastic-elastoplastic constitutive model,which is presented in this paper for the rutting of the asphalt pavement,is effective. The properties,such as nonlinear elastic-ity,plasticity,viscoelasticity and nonlinear viscoelasticity,which affect the rutting of an asphalt pavement,can be shown in the model. And the characteristics of the permanent deformation of the asphalt pavement can be presented entirely in the model.

关键词： asphalt pavement,permanent deformation,nonlinear viscoelastic-elastoplastic constitutive relationship,generalized Maxwell model,creep compliance.

Unified solutions for stresses and displacements around circular tunnels using the Unified Strength Theory

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Science China(Technological Sciences) 2010年第6期53卷 1694-1699页

作者： ZHANG ChangGuang1,WANG JiangFeng2 & ZHAO JunHai3.1 department of geotechnical engineering,{3.,shanghai 200092,China 2 North China Institute of Water Conservancy and Hydroelectric Power,Zhengzhou 450011,China 3.School of Civil engineering,Chang’an university,Xi’an 710061,China 1. department of geotechnical engineering Tongji University Shanghai 200092 China2. North China Institute of Water Conservancy and Hydroelectric Power Zhengzhou 450011 China3. School of Civil Engineering Chang’an University Xi’an 710061 China

The unified solutions are presented for stresses and displacements around a circular tunnel subjected to a hydrostatic stress *** rock mass is assumed to be elastic-brittle-plastic and governed by the Unified Strength *** displacements are obtained accounting for three different definitions for elastic strains and different Young's modulus in the plastic *** unified solutions obtained in this paper are especially versatile in reflecting the intermediate principal stress effect to different extents for different *** conventional solutions,based on the Mohr-Coulomb failure criterion and the Generalized Twin Shear Stress yield criterion,are special cases of the present unified *** new unified solutions can compare with those computed by the latest generalized Hoek-Brown failure *** results obtained demonstrate the importance of the intermediate principal stress influence for the stresses and displacements *** effects of different definitions for elastic strains and different Young's modulus in the plastic zone on the displacements are significant.

关键词： Unified Strength Theory intermediate principal stress different definitions for elastic strains different Young’s modulus

Preliminary design and parametric study of 1400 m partially earth-anchored cable-stayed bridge

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Science China(Technological Sciences) 2010年第2期53卷 502-511页

作者： SUN Bin, CHENG Jin & XIAO RuCheng department of Bridge engineering, tongji university, {3., China 1. department of Bridge engineering Tongji University Shanghai 200092 China

The preliminary design and parametric study of 1400 m partially earth-anchored cable-stayed bridge are described. Static per-formance of this new type of bridge is discussed. Compared with fully self-anchored cable-stayed bridge, its advantages in fin-ished state are summarized. Based on numerical calculation, effects of several structural parameters on static performance are presented.

关键词： partially earth-anchored cable-stayed bridge preliminary design parametric study

Simultaneously inducing synthesis of semiconductor selenium multi-armed nanorods and nanobars through bio-membrane bi-templates

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Science China Chemistry 2004年第6期47卷 507-511页

作者： LI Li1, WU Qingsheng1 DING Yaping2 & LI Ping3.1. department of Chemistry, tongji university, shanghai 200092, China 2. department of Chemistry, shanghai university, shanghai 20043., China 3. department of Food, Anhui Agricultural university, Hefei 23.03., China 1. department of Chemistry Tongji University 200092 Shanghai China 2. department of Chemistry Shanghai University 200436 Shanghai China 3. department of Food Anhui Agricultural University 230036 Hefei China

Multi-armed nanorods and nanobars of semiconductor selenium were simultane- ously synthesized in the light of biomineralization process through bio-membrane bi-templates of rush at room temperature. The multi-armed nanorods are 60 nm in diameter and 1.5 μm in length; the nanobars are 150 nm in diameter and 1000—1100 nm in length. The XRD pattern indicates that these nanocrystals were crystallized in the hexagonal structure with lattice constants a = 0.43. nm, c = 0.495 nm. The possible formation mechanism was investigated.

关键词： selenium, multi-armed nanorods, nanobars, bio-membrane, bi-templates.

STABILITY OF IMPULSIVE LINEAR HYBRID SYSTEMS WITH TIME DELAY

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Journal of Systems Science & Complexity 2010年第4期23卷 738-747页

作者： Yu ZHANG·Jitao SUN department of Mathematics,tongji university,shanghai 200092,China. JitaoSUN department of Mathematics Tongji University

This paper investigates the stability of impulsive linear hybrid systems with time *** a number of delay-independent/delay-dependent stability criteria are obtained by using Lyapunovfunctions or Lyapunov *** examples ... 详细信息

关键词： Impulsive linear hybrid system Lyapunov function Lyapunov functional time delay.