Engineering Questions with Answers - Multiple Choice Questions
Basic Civil Engineering MCQ’s – Seasoning of Timber
Seasoning of timber is the process of:
a) Burning timber
b) Adding preservatives
c) Removing water
d) Adding glaze
Explanation: Tree when felled contains sap and high moisture content. To use it for engineering purpose, it has to be dried. The process of drying timber to remove water is called seasoning.
Which of the below changes do not occur after seasoning?
a) Increase durability
b) Decrease stiffness
c) Workable timber
d) Reduction in weight
Explanation: Seasoning increases the stiffness of timber. It takes away sap and moisture content and imparts stiffness to timber.
Kiln seasoning gives stronger timber.
Explanation: Natural seasoning is the one that gives stronger timber. Kiln seasoning results in weaker, lighter timber.
How much time does natural seasoning takes for timber to be properly seasoned?
a) 1-4 years
b) 6-12 months
c) 5-10 months
d) 5-7 years
Explanation: Natural seasoning is a very slow process, as timber is stacked and blowing natural wind seasons it. It may take anywhere from 1-4 years for obtaining properly seasoned timber.
Which of the below is a disadvantage of air seasoning?
a) Power requirement
b) Skilled supervision
c) Elaborate equipment
d) Uniformity of seasoning
Explanation: Air or natural seasoning does not require power, skilled supervision and elaborate equipment. These are all advantage of air seasoning. It might not give uniformly seasoned timber.
How many methods of artificial seasoning are there?
Explanation: The 5 types are water seasoning, boiling, chemical seasoning, electrical seasoning and kiln seasoning.
Which method leaves the timber brittle after seasoning?
a) Water seasoning
b) Kiln seasoning
c) Electric seasoning
Explanation: Timber pieces are totally immersed in running water for 2-4 weeks. The sap, organic matter is carried away by water in water seasoning. It renders the timber brittle.
Which of the below chemicals is not used in chemical seasoning?
a) Sodium chloride
c) Sodium hypochlorite
d) Sodium nitrate
Explanation: Chemicals used are dehydrating agents. Timber is immersed in such salt solutions and allowed to reduce water content. Sodium hypochlorite is a disinfectant.
Which is the most rapid and effective method of seasoning?
a) Chemical seasoning
b) Electric seasoning
c) Kiln seasoning
d) Natural seasoning
Explanation: Electric seasoning involves passing high electricity through timber. Since it is a bad conductor of electricity, it gets heated up. It results in rapid seasoning and it is effective as it provides uniform seasoning.
In kiln seasoning, the temperature of air inside chamber and humidity is high.
Explanation: Seasoning starts at low temperature and high humidity. As it proceeds, conditions are gradually altered. At the end, in the chamber, temperature is high and the humidity is low.
For how long is timber boiled in water in the seasoning method of boiling?
a) 3-4 hours
b) 1-2 hours
c) 5-6 hours
d) 10-12 hours
Explanation: Timber is immersed in water and allowed to boil for 3-4 hours. Then it is taken into shed and dried very slowly.