Soil Mechanics Chapter 5: Compaction of Soil – 20 PYQs Quiz with Answers

Soil Mechanics – Chapter 5

Compaction of Soil | 20 PYQs | Interactive 20 Marks Quiz

Chapter 5: Compaction of Soil
Is quiz mein OMC, MDD, Proctor test, compaction energy, zero air voids, field compaction, rollers, relative compaction aur compaction curve ke important PYQs cover kiye gaye hain.

20 Questions = 20 Marks

Quiz Instructions: Har question 1 mark ka hai. Option select karke Check Answer dabao. Sabhi 20 questions complete hone ke baad score aur percentage automatically show hogi.

Progress: 0/20 Score: 0/20

GATE 1992

1. Zero-air-voids curve nonlinear kyon hoti hai?

A) Proctor test curve nonlinear hoti hai B) 100% saturation par dry density void ratio ka nonlinear function hoti hai C) Water content compaction ke dauran change hota hai D) Number of blows odd hota hai

Answer: B)
Zero-air-voids condition mein dry density void ratio ke relation ke karan nonlinear curve milti hai.

GATE 1995

2. Zero-air-voids condition par soil ka unit weight kin quantities par depend karta hai?

A) Specific gravity B) Water content C) Unit weight of water D) All of the above

Answer: D) All of the above
Zero-air-voids relation mein G, water content aur γw sab relevant hote hain.

GATE 1995

3. Soil compaction ko measure karne ke liye wet density ki jagah kaunsi density use ki jati hai?

A) Saturated density B) Dry density C) Bulk density only D) Submerged density

Answer: B) Dry density
Soil compaction ka standard measure dry density hota hai.

GATE 1997

4. Compaction effort badhane par optimum moisture content:

A) Decreases B) Remains same C) Increases D) Pehle increase phir decrease

Answer: A) Decreases
Higher compactive effort se MDD increase aur OMC decrease hota hai.

GATE 2003

5. Embankment compaction ke energy-equivalence numerical mein Indian Standard light compaction ke equivalent passes/blows approximately kitne aaye?

A) 10 B) 16 C) 20 D) 25

Answer: D) 25
GATE 2003 numerical mein energy comparison se approximately 24.71, yani 25, aata hai.

GATE 2005

6. Ek clayey soil ka MDD 16 kN/m³ aur OMC 12% hai. Field mein dry density 15.2 kN/m³ aur water content 11% mila. Situation acceptable hone ka reason kya hai?

A) Density MDD se kam hai aur water content OMC ke dry side par hai B) Density bahut low hai C) Compaction wet side par hua hai D) Water content 12% se zyada hai

Answer: A)
Given field condition dry side of OMC par hai, jo specified acceptable range mein hai.

GATE 2006

7. Standard Proctor test mein G = 2.7 aur given moisture content par theoretical maximum dry unit weight kitna hai?

A) 4.67 kN/m³ B) 11.5 kN/m³ C) 16.26 kN/m³ D) 18.85 kN/m³

Answer: D) 18.85 kN/m³
GATE 2006 numerical mein zero-air-void condition apply karne par 18.85 kN/m³ milta hai.

GATE 2008

8. Vibratory roller sabse suitable kis soil ke compaction ke liye hai?

A) Moist silty sand B) Well-graded dry sand C) Medium compressibility clay D) Highly compressible silt

Answer: B) Well-graded dry sand
Vibratory rollers granular soils, especially sands aur gravels, ke liye highly effective hote hain.

GATE 2010

9. Zero-air-voids line ke liye dry unit weight ka correct relation kaunsa hai?

A) γd = Gγw / (1 + Se) B) γd = Gγw / (1 + Gw) C) γd = Gw / (1 + γwS) D) γd = Gw / (1 + Se)

Answer: B)
Zero-air-voids condition ke liye S = 1 hota hai aur relation γd = Gγw/(1+Gw) obtain hota hai.

GATE 2012

10. Higher compaction energy use karne par OMC aur MDD ka kya trend hota hai?

A) OMC increases, MDD decreases B) OMC decreases, MDD increases C) Both decrease D) Both increase

Answer: B)
Higher energy → higher MDD + lower OMC.

GATE 2013

11. Dry-side aur wet-side compaction ke statements mein incorrect statement kaunsa hai?

A) Dry side par structure relatively flocculated hota hai B) Wet side par pore-water pressure higher develop ho sakta hai C) Drying par shrinkage dry side par low hota hai D) Wet side par swelling comparatively low ho sakti hai

Answer: C)
GATE 2013 mein incorrect statement tha ki dry side par drying shrinkage low hota hai. Correct trend iska opposite hai.

GATE 2016 Set-II

12. Standard Proctor aur Modified Proctor ke OMC-SP, MDD-SP, OMC-MP aur MDD-MP ke beech correct relation kya hai?

A) OMC-SP < OMC-MP and MDD-SP < MDD-MP B) OMC-SP > OMC-MP and MDD-SP < MDD-MP C) OMC-SP < OMC-MP and MDD-SP > MDD-MP D) OMC-SP > OMC-MP and MDD-SP > MDD-MP

Answer: B)
Modified Proctor ka energy higher hota hai, isliye MDD higher aur OMC lower hota hai.

GATE 2022 Set-I

13. Uncompacted soil ka volume 10000 m³ aur void ratio 1 hai. Compaction ke baad volume 7500 m³ ho gaya. Compacted soil ka void ratio approximately kya hoga?

A) 0.25 B) 0.50 C) 0.75 D) 1.25

Answer: B) 0.50
Initial Vs = 10000/(1+1) = 5000 m³. Final V = 7500 m³, hence Vv = 2500 m³. Therefore e = 2500/5000 = 0.50.

GATE 2023 Set-I

14. Compaction test ke regarding following mein INCORRECT statement kaunsa hai?

A) Compaction curve ka peak MDD aur OMC deta hai B) Compaction effort badhne par MDD increase hota hai C) Compaction effort badhne par OMC decrease hota hai D) Compaction curve zero-air-voids curve ko cross karti hai

Answer: D)
Actual compaction curve theoretical zero-air-voids curve ko cross nahi karti.

GATE 2024

15. Ek embankment ko compaction ke dauran 75% degree of saturation par maintain kiya gaya. G = 2.68 aur water content = 17% hai. Is type ke numerical mein void ratio nikalne ke liye kaunsa relation use hoga?

A) e = wG/S B) e = wG/Sr C) e = Sr/(wG) D) e = w/(G Sr)

Answer: B) e = wG/Sr
Phase relation: Sr × e = wG, hence e = wG/Sr.

RSMSSB JE Civil 2021

16. Indian Standard Light Compaction Test mein hammer ka approximate weight kitna hota hai?

A) 6.5 kg B) 2.6 kg C) 4.5 kg D) 10 kg

Answer: B) 2.6 kg
Indian Standard Light Compaction test mein 2.6 kg rammer aur approximately 310 mm drop use hota hai.

DDA JE Civil 2023

17. Compaction curve par water content badhne se dry density initially:

A) Continuously decrease hoti hai B) Maximum dry density tak increase hoti hai C) Hamesha constant rehti hai D) Zero ho jati hai

Answer: B)
Water content initially increase karne par lubrication ke karan dry density increase hoti hai aur OMC par MDD milti hai.

SSC JE Civil 10 Oct 2023 Shift-1

18. Subgrade compact karne ke baad desired compaction achieve hua hai ya nahi, ise check karne ke liye kaunsa test kiya jata hai?

A) Consolidation test B) Moisture content and field density determination C) Compaction and triaxial shear test D) Direct shear test

Answer: B)
Field density aur moisture content determination se achieved field compaction verify ki jati hai.

SSC JE Civil 05 Dec 2025 Shift-2

19. Modified Proctor test mein compactive effort increase karne par kya trend hota hai?

A) OMC increases and MDD increases B) OMC decreases and MDD increases C) OMC increases and MDD decreases D) OMC decreases and MDD decreases

Answer: B)
Compactive effort increase → MDD increase aur OMC decrease.

SSC JE Civil 06 Dec 2025 Shift-2

20. Agar moisture content OMC se zyada ho jaye, to dry density ka kya effect hota hai?

A) Increases B) Decreases C) Same rehti hai D) Unpredictable ho jati hai

Answer: B) Decreases
OMC ke baad additional water soil particles ko lubricate karta hai aur dry density decrease hone lagti hai.

🎯 Quiz Complete!

Quick Revision – Compaction of Soil

Compaction: Mechanical means se mainly air voids reduce karke soil density increase karna.

OMC: Water content at which maximum dry density (MDD) is obtained.
MDD: Given compactive effort ke liye maximum dry density.
Compactive effort ↑: MDD ↑ and OMC ↓
Standard / Light Proctor: 2.6 kg rammer, approximately 310 mm drop, 3 layers, 25 blows/layer.
Modified / Heavy Proctor: 4.54 kg rammer, approximately 457 mm drop, 5 layers, 25 blows/layer.
Zero Air Voids: Theoretical condition where air content = 0 and degree of saturation = 100%.
Rollers: Vibratory roller → granular soil
Sheepsfoot roller → cohesive soil
Smooth wheel roller → granular soil / finishing
Pneumatic roller → wide range of soils