摘要:

AbstractThe study presented herein concerns the double‐layer repulsive force that exists between clay particles in a clay–water–electrolyte system. The objective is to examine the nature of the double‐layer repulsive force between two negatively charged clay particles that are inclined to each other and have finite length. The finite element numerical technique is used first to determine the spatial distribution of the electric potential. The net repulsive force and its location are then evaluated from this known distribution of the potential on the basis of the theory of electrostatics. A systematic parametric study is performed by varying certain dimensionless system variables, particularly to investigate the effect of orientation, surface potential and particle length. It is found that for non‐parallel orientation, as the value of inclination and surface potential increase, the repulsive force decreases and its location shifts towards the particle ends that are closer to e

ISSN:0363-9061    

DOI:10.1002/nag.1610151002

出版商:John Wiley&Sons, Ltd    

年代:1991

数据来源: WILEY

摘要:

AbstractIn this article we solve the equations for a 2D model of compaction of sedimentary basins saturated with water by the finite‐element method. This compaction model considers the rock described by the porosity as a function of effective stress, and both the anisotropic permeability and the anisotropic heat conductivity as functions of porosity. The water density is approximated linearly in the water pressure and temperature, and the water viscosity is a function of temperature. The main variables in the model are the water excess pressure and the temperature, and we account for an implicit solution scheme where we solve for both main variables simultaneously. The non‐linearities in the model are either dealt with by the Newton method or by fixed‐point iterations. We compare the coupled solution of temperature and pressure with the same decoupled equations. Then we study the contribution to the temperature by convection, the effect of the non‐constant water density, and some anisotropic case e

ISSN:0363-9061    

DOI:10.1002/nag.1610151003

出版商:John Wiley&Sons, Ltd    

年代:1991

数据来源: WILEY

摘要:

AbstractA direct boundary element method for the iterative analysis of the lowered groundwater level and the steady‐state airflow in porous soil for tunnels driven under compressed air is presented. The soil may be zoned and anisotropic. It is shown that disregard of the compressibility of the air leads to results for the excess air pressure and the flow of air through the surface of the soil, which are on the unsafe side. The lowered groundwater level is determined by means of an iterative procedure. During the iteration large changes of the shapes of boundary elements may occur. In order to reduce the resulting danger of divergence of the iteration, the boundary element mesh is adapted suitably in the course of the iteration proces

ISSN:0363-9061    

DOI:10.1002/nag.1610151004

出版商:John Wiley&Sons, Ltd    

年代:1991

数据来源: WILEY

ISSN:0363-9061    

DOI:10.1002/nag.1610151005

出版商:John Wiley&Sons, Ltd    

年代:1991

数据来源: WILEY

ISSN:0363-9061    

DOI:10.1002/nag.1610151006

出版商:John Wiley&Sons, Ltd    

年代:1991

数据来源: WILEY

ISSN:0363-9061    

DOI:10.1002/nag.1610151001

出版商:John Wiley&Sons, Ltd    

年代:1991

数据来源: WILEY