Engineering Rock Mechanics

42 In situ rock stress . Figure 4.2 Perturbation of in situ rock stress state caused by a fracture. effect adjacent to many frac ...

Questions and answers: in situ rock stress 43 1 44.2 Add the following 2-D rock stress states, and find the principal stresses a ...

44 In situ rock stress -10.0. -5.0. 0. 5.0. Shear stress, -7 I. , I , I , , , , 5.0 10.0 15.0 -5.01 oX,rs= 14.52, -1.17 30.0 0 % ...

Questions and answers: in situ rock stress^45 A4.3 TheJatjack method measures one normal stress; so, given that the stress tenso ...

46 In situ rock stress Finally, because each flatjack measures the normal stress component perpendicular to the flatjack, we add ...

-- - OA cos2 sin2 6.4 2 sin $A COS $A- OB cos2 & sin2 & 2 sin cos OD cos2 e, sin2 2 sin e, cos e, -aE - cos2 & sin2 ...

48 In situ rock stress The expected stresses, a,, are given by OA = 7.56 MPa, aB = 6.94 ma, ac = 7.37 MPa, UD = 7.19 MPa, and UE ...

Questions and answers: in situ rock stress 49 such as regions of thrust faults where the stress is being transmitted through sma ...

50 In situ rock stress The values are consistent with each other and they are consistent with worldwide trends. The value of k = ...

Questions and answers: in situ rock stress 5 1 and z = down, and take direction n as normal to the desired plane, then nx =COSan ...

52 In situ rock stress A4.8 The stress transformation equations are given by which can be written as Olmn = RuXy,RT. This means ...

Questions and answers: in situ rock stress 53 matrix. The third invariant is computed as the determinant of the stress matrix. 1 ...

54 In situ rock stress With the I axis parallel to the strike of the plane and the n axis normal to the plane, the m axis is the ...

Questions and answers: in situ rock stress 55 44.10 The plan below (Sugawara and Obara, 19997) shows a ho- rizontal section thro ...

56 In situ rock stress To interpret these results further, we would have to study the 3-D states of stress at the measurement po ...

Strain and the theory of 5 elasticity 5.1 Stress and strain are both tensor quantities The concept of strain is required to unde ...

58 Strain and the theory of elasticity stress Strain Components of the stress and strain matnces - relatlve to x, y and z refere ...

Stress and strain are both tensor quantities 59 e = Sa 21 independent c:E:ts where E = anda = and S = It can be shown from energ ...

60 Strain and the theory of elasticity Table 5.2 Number of elastic constants required to characterize different forms of rock ma ...

Questions and answers: strain and the theory of elasticity 61 45.2 The differential equations of force equilibrium were the subj ...