Consider the following statements for precast driven piles 1.Piles can be installed without much noise, vibration 2.Being non-displacement pile, no risk of heave 3.Good quality control
- AOnly 3 and 2 are correct
- BOnly 3 is correctCorrect
- COnly 2 is correct
- DOnly 1 and 3 are correct
Solution
Concept
Precast driven piles are displacement piles known for causing noise and vibration, soil heave, but excellent structural quality control.
Step-by-step solution
1. Analyze statement 1: Precast driven piles involve heavy hammering/driving, which produces high noise and considerable ground vibration. Thus, statement 1 is incorrect. 2. Analyze statement 2: Driven piles displace a volume of soil equal to the pile volume, making them displacement piles (not non-displacement piles), which creates a high risk of soil heave. Thus, statement 2 is incorrect. 3. Analyze statement 3: Since precast piles are cast and cured in a controlled environment (casting yard) prior to installation, their material quality and dimensional accuracy are strictly controlled. Thus, statement 3 is correct.
Explanation
Precast driven piles are displacement piles that cause significant noise, vibration, and soil heave during driving. However, because they are cast and cured under factory or controlled site conditions before driving, they offer excellent quality control.
Why the other options are wrong
A: Statement 2 is incorrect because driven piles are displacement piles, not non-displacement piles, and cause heave. C: Statement 2 is incorrect as explained above. D: Statement 1 is incorrect because driven piles produce substantial noise and vibration.
Shortcut
Driven piles = displacement piles = high noise, vibration, and heave, but good pre-manufactured quality.
Common mistake
Confusing driven piles with bored piles (which are replacement/non-displacement piles).
Correct answer: B) Only 3 is correct