Rock Mechanics and Roof Supporting MCQs Questions & Answers | Mining Engineering

Home / Mining Engineering / Rock Mechanics And Roof Supporting

52.
The measurements of a site investigation are as follows:
In = 9, Jr = 1.5, Ja = 2.0, Jw = 1.0. SRF = 2.5. The RQD values taken from five boreholes of the area are 94.2, 95.6, 99.4, 95.3 and 98.0 respectively. The rock mass quality index (Q) is

Answer & Solution Discuss in Board Save for Later

53.
The objective of such activity is to restrict displacements of the country rock to elastic orders of magnitude and to maintain as far as practicable the integrity of both the country rock and the unmined remnants within the ore body. Identify the mining activity?

Answer & Solution Discuss in Board Save for Later

54.
During uniaxial compressive testing of a rock specimen of diameter 54 mm and length 120 mm, the axial strain was found to be 6.5 × 10-4 mm/mm. If the Poisson's ratio of the rock is 0.3, the volumetric strain of the rock specimen in mm/mm is

Answer & Solution Discuss in Board Save for Later

55.
From a series of tri-axial tests conducted on some sandstone specimens, the relationship between the major and the minor principal stresses in MPa is found to be σ1 = 100 + 5 σ3. The angle of internal friction in degrees of that sandstone is

Answer & Solution Discuss in Board Save for Later

56.
The components of state of stress at a point in x - y plane are given as σxx = 5 MPa, σyy = 10MPA and $${\tau _{xy}}$$ = 2MPa. The sum of the principal stresses acting on the x - y plane in MPa is

Answer & Solution Discuss in Board Save for Later