Mechanics

2004, Special Issue

S.V. Zatsepina

THE EFFECT OF THE ASPECT OF RELATIVE PHASE PENETRABILITY ON THE OIL BASIN MODELING

By numerous researches it has been remarked that relative enetrability of gas and condensate can considerably magnified t increase discharge. In the paper the results of this phenomenon peration research carried out on hydrodynamic model of gas-condensate asin by the software package VIP Landmark are given.

E.I. Kondrateva, Zh.I. Mamatov, B.A. Riychkov

DILATANCY OF GEOMATERIALS DUE TO LOSS OF STRENGTH

Kinematic and strength properties of the rock from viewpoint of the sliding and loosening concepts on example of the cylindrical specimens behaviour under triaxial compression are considered. The relations for determination of the shear planes orientation at fracture state are obtained. The values of the shear angle are shown to be in good agreement with known experimental data at complex stress state.

L.V. Stepanova, T.N. Makarova

FINITE DIFFERENCE METHOD APPROACH TO A CREEP-DAMAGE COUPLED MODE III CRACK PROBLEM

An attempt to describe stress, creep strain rate and continuity (integrity) fields near a Mode III crack tip in the framework of the continuum damage mechanics by the aid of finite difference method is presented. The scalar damage parameter is involved into the power creep constitutive equations. The coupled system of continuum damage mechanics–creep theory equations is considered. The solution is based on introducing a self–similar variable proposed by Riedel for the creep power constitutive law coupled to the power kinetic law of the damage evolution. The stress, strain rate and damage fields near the crack tip are obtained as the functions of the similarity variable assuming the existence of a totally damaged zone. It is presumed that there is the totally damaged zone in the crack-tip region where the damage parameter reaches its critical value and all the stresses are equalled to zero. All the equations of the considered boundary value problem are then formulated as the finite difference equations resulting in the linear algebraic system of equations. The left difference scheme is employed for the approximation. The shape and the characteristic length of the totally damaged zone are found from the obtained solution.