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The major principal stress at the toe of a gravity dam under full reservoir condition neglecting the tailwater effect is given by ____________________

The major principal stress at the toe of a gravity dam under full reservoir condition neglecting the tailwater effect is given by ____________________ Correct Answer Pv secQ2

When there is no tailwater, the principal stress in such a case is Pv secQ2 where Pv is the intensity of vertical pressure. This value of principal stress should not be allowed to exceed the maximum allowable compressive stress of dam material.

Related Questions

Which of the following statements are true with regard to energy dissipation below a dam? (i) If the upper conjugate depth of a hydraulic jump is below the tailwater, little energy will be dissipated (ii) An upturned bucket will protect the dam from scour by moving material toward the dam. (iii) A secondary dam may increase tailwater height, thereby causing a hydraulic jump to form at the toe of the main dam. (v) A slopping apron above streambed level may be used to control the hydraulic jump so that it occurs on the apron. 
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A concrete gravity dam having a maximum reservoir level at 200 m and the RL of the bottom of the dam 100 m. The maximum allowable compressive stress in concrete is 3000 KN/m2 and the specific gravity of concrete is 2.4. Calculate the height of the dam and check whether it is a high dam or low dam.
Presence of tail water in a gravity dam
i) increases the principal stress
ii) decreases the principal stress
iii) increases the shear stress
iv) decreases the shear stress
The correct answer is
Tresca or maximum-shear stress criteria assumes that yielding occurs when the maximum shear stress reaches a value of the shear stress in the uniaxial tension test. Assume the principal stress being σ1, σ2, σ3 where σ1 is largest, and σ3 is the smallest principal stresses. Find the value of minimum shear stress to cause yielding, given that yield stress in tension is equal to σo?
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From an alloy, two specimens are machined and tested separately under tension and compression. The engineering stress-strain curves as well as the true stress-true strain curves for tension and compression are plotted in the same diagram. Identify the correct statements:
P. The engineering stress-strain curves in tension and compression are identical.
Q. The true stress-true strain curve in compression is lower than the true stresstrue strain curve in tension due to Bauschinger effect.
R. The true stress-true strain curve in tension is above the corresponding engineering stress-strain, curve.
S. The true stress-true strain curve in tension and compression are identical.
The governing compressive stress in a concrete gravity dam which should not be allowed to exceed the permissible value of about 3000 KN/m2 while analyzing full reservoir case is ____________________