Concept explainers
A steel pipe is subjected to a quadratic distributed load over its height with the peak intensity q0at the base (see figure). Assume the following pipe properties and dimensions: height L, outside diameter d = 200 mm, and wall thickness f = 10 mm. Allowable stresses for flexure and shear are o~a=125 MPa and Ta= 30 MPa,
- If L = 2.6 m, Fmd^0ayM (kN/m), assuming that allowable flexure and shear stresses in the pipe are not to be exceeded.
- If q0= 60 kN/m, find the maximum height Lraajl(m) of the pipe if the allowable flexure and shear stresses in the pipe arc not to be exceeded.
(a)
The maximum uniform load intensity
Answer to Problem 5.9.6P
The maximum load intensity
Explanation of Solution
Given information:
The allowable stress is
Write the expression intensity.
Here, the intensity is
Write the expression for the differential Equation.
Here, the modulus of elasticity is
Integrate the Equation (II) with respect to x.
Applying, the boundary condition at point
Here, the reaction force at
Substitute
Applying, the boundary condition at point
Here, the reaction force at the point
Integrate the Equation (V) with respect to x.
Substitute
Here, the bending moment is
Applying the boundary condition at fixed end
Applying the boundary condition at proper end
Substitute
Substitute
Differentiate the Equation (X) with respect to x
Write the expression of the flexible stress.
Here, the allowable stress is
Write the expression of the allowed shear stress.
Here, the shear stress is
Write the expression for the area.
Calculation:
Substitute
Substitute
Substitute
Substitute
Substitute
Conclusion:
The maximum load intensity
(b)
The maximum height of the pipe.
Answer to Problem 5.9.6P
The maximum height of the pipe is
Explanation of Solution
Write the expression of the bending moment in terms of length.
Calculation:
Substitute
Conclusion:
The maximum height of the pipe is
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Chapter 5 Solutions
Mechanics of Materials (MindTap Course List)
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- Mechanics of Materials (MindTap Course List)Mechanical EngineeringISBN:9781337093347Author:Barry J. Goodno, James M. GerePublisher:Cengage Learning