Practice Question: Effective Stress on a Soil Profile

NCEES Civil PE Specification III.C.: Effective and Total Stresses

Problem

Given the following soil profile, determine the effective stress at bottom of Soil Layer 2:

Select an Answer:

CORRECT 😃

INCORRECT 😟

% Students Correctly Answered:

46.5%

Solution

Answer: B) 2954 psf

Effective stress is calculated based on the portion of stress that may be resisted by soil contact. To calculate effective stress, first calculate total stress at the bottom of layer 2, then subtract pore water pressure. Note that the layer of water above soil layers is ignored in this calculation.