the state of stress

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1. The state of stress (MPa) at a point is given by σ x =13.78 = , σ y = 26.2, σ z = 41.34, τ xy = 27.56, τ yz = 6.89 and τ xz = 10.34. Determine the stress resultants and the normal and shear stresses for a plane whose normal makes angles of 50° 70’ and 60° with the directions of x and y respectively. Solution: α = 50° 70’ ; β= 60° ; γ = ? l = Cos α = 0.62705; m = Cos β = 0.50. We know that l 2 +m 2 +n 2 = 1 and hence n = Cosγ = 0.597 which implies γ = Cos -1 0.597 = 53° 23’ S = 56.609 and Stress Resultants S x = 28.59 ; S y = 34.49; S z = 34.608 and ; 2. At a point in a material, the state of stress in MPa is given by the components σ x = 12.8, σ y = 27, σ z = 51.3, τ xy = 23.4, τ yz = -6.24 and τ xz = 11 Determine the normal and shear stresses on a plane whose normal makes angles of 48° and 71 ° to the x and y axes respectively. Also find the direction of the shear stress relative to x and y. Solution: l = Cos α = 0.66913; m = Cos β = 0.3255. We know that l 2 +m 2 +n 2 = 1 and hence n = Cosγ = 0.6680 ° 5’ 3’’ σ = =48.79 S 2 =2532.9 and S = 50.328

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The State of Stress

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The state of stress (MPa) at a point is given by x =13.78 = , y = 26.2, z = 41.34, xy = 27.56, yz = 6.89 and xz = 10.34. Determine the stress resultants and the normal and shear stresses for a plane whose normal makes angles of 50 70 and 60 with

The state of stress (MPa) at a point is given by x =13.78 = , y = 26.2, z = 41.34, xy = 27.56, yz = 6.89 and xz = 10.34. Determine the stress resultants and the normal and shear stresses for a plane whose normal makes angles of 50 70 and 60 with the directions of x and y respectively. Solution:

= 50 70 ;

= 60 ;

= ?

l = Cos = 0.62705;

m = Cos = 0.50.

We know that l2 +m2+n2 = 1 and hence n = Cos = 0.597

which implies = Cos-1 0.597 = 53 23

S = 56.609 and

EMBED Equation.KSEE3 \* MERGEFORMAT

Stress Resultants Sx = 28.59 ; Sy = 34.49; Sz = 34.608 and ;

At a point in a material, the state of stress in MPa is given by the components x = 12.8, y = 27, z= 51.3, xy = 23.4, yz = -6.24 and xz = 11 Determine the normal and shear stresses on a plane whose normal makes angles of 48 and 71 to the x and y axes respectively. Also find the direction of the shear stress relative to x and y.Solution:

l = Cos = 0.66913;

m = Cos = 0.3255.

We know that l2 +m2+n2 = 1 and hence n = Cos = 0.6680 5 3

= =48.79

S2=2532.9 and S = 50.328

Directions of shear stress are

A stress resultant of 140 MPa makes angles of 43,75 and 5053' with the x and y axes. Determine the normal and shear stresses on an oblique plane whose normal makes respective angles of 67 13'',30and 7134 with these axes.Solution:

S=140

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