Question

Following data were obtained from the stability analysis of a concrete gravity dam:
Weight of the dam = 6500 tonnes/m
Uplift force = 1500 tonnes/m
Base width of dam = 60 m
The resultant force acts at 25 m from the toe.
The maximum vertical stress on the foundation soil will be

• A. $291.67t/m^2$
• B. $125t/m^2$
• C. $41.67t/m^2$
• D. $162.5t/m^2$

Answer 1

The correct option is B $125t/m^2$

Since resultant force acts at 25 m from the toe,
Eccentricity, e = 30 - 25 = 5 m

Maximum vertical stress,
$P_{max}=\frac{F_v}{B}[1+\frac{6e}{B}]$
$P_{max}=\frac{6500-1500}{60}[1+\frac{6\times 5}{60}]=125t/m^2$