Determine percent of Coarse, Silt and Clay

Problem 1: In a sieve analysis  30% passing 4.75 mm sieve and 2% passing in the 0.075 mm sieve. Determine percent of coarse, silt and clay?
Exam name: BIPCL 2015

Solution:

Sieve Size	% of Retain
4.75 mm	(100-30)% = 70%
0.075 mm	(30-2)% = 28%

Passing through 0.075 mm sieve 2%

So,
Percentage of coarse = 70%
Percent of silt and clay = 2%

---

Problem 2:  Difference between initial setting time and final setting time.
Exam Name: PGCB 2017 

Answer:  

Initial Setting Time	Final Setting Time
1. It is the interval between the moment water added to the cement to the time paste start loosing it's plasticity	1. The time taken to reach the stage when the paste becomes a hard mass and can sustain some minor load is known as final setting time. 2
2. It should be less than 30 minutes	2. It should not be more than 10 hours.

---