Consider the following statements regarding bearing capacity values specified in building codes : 1. The codes tacitly assume that the allowable bearing capacity is dependent only on the soil type. 2. The codes assume that the bearing capacity is dependent of the size, shape and depth of foundation. 3. Building codes are usually not up-to-date. Which of the above statements are correct ?
- A1 and 2 only
- B1 and 3 onlyCorrect
- C2 and 3 only
- D1, 2 and 3
Solution
Concept
Presumptive bearing capacity in codes
Step-by-step solution
1. Codes tabulate allowable (presumptive) values by soil type only (statement 1 true). 2. They do not account for the size, shape and depth of the foundation (statement 2 false). 3. Code values are often outdated compared with current knowledge (statement 3 true).
Explanation
Presumptive bearing values are simple tables that ignore foundation geometry, so they are conservative or unreliable in some cases.
Why the other options are wrong
Statement 2 is the opposite of the facts.
Shortcut
Code tables: soil type only, not B and D.
Common mistake
Accepting statement 2.
Correct answer: B) 1 and 3 only