,Transversely isotropic rock mass,Geostress,Finite element model,Stress error," />
Influence of Formation Dip Angle on the Geostress Calculation of
a Transversely Isotropic Rock Mass
Abstract The 3D geostress is an important parameter in the structural design and construction of underground works. Overcoring stress relief is the most commonly used method to measure geostress at present, but it cannot take into account the influence of the formation dip angle. In engineering applications, ignoring or modifying the influence of the formation dip angle can often cause greater errors in geostress measurement. According to the calculation principle of finite element method, solutions for geostress measurement of a transversely isotropic rock mass were studied with the formation dip angle varying from 0°~ 90° in order to make appropriate adjustments to the geostress values measured during tunneling. The results show that the formation dip angle chiefly has a great influence on the normal stress in the plane perpendicular to the hole, with the tendency to increase at first and then decrease; and the influence is most obvious at 45° of the formation dip angle, with the errors of the first, second, and third principal stress being 19.00%, 10.86% and 88.98% respectively.
Abstract：
The 3D geostress is an important parameter in the structural design and construction of underground works. Overcoring stress relief is the most commonly used method to measure geostress at present, but it cannot take into account the influence of the formation dip angle. In engineering applications, ignoring or modifying the influence of the formation dip angle can often cause greater errors in geostress measurement. According to the calculation principle of finite element method, solutions for geostress measurement of a transversely isotropic rock mass were studied with the formation dip angle varying from 0°~ 90° in order to make appropriate adjustments to the geostress values measured during tunneling. The results show that the formation dip angle chiefly has a great influence on the normal stress in the plane perpendicular to the hole, with the tendency to increase at first and then decrease; and the influence is most obvious at 45° of the formation dip angle, with the errors of the first, second, and third principal stress being 19.00%, 10.86% and 88.98% respectively.
.Influence of Formation Dip Angle on the Geostress Calculation of
a Transversely Isotropic Rock Mass[J] MODERN TUNNELLING TECHNOLOGY, 2013,V50(5): 75-79
2013, Vol. 50 