🔹 1. Introduction

Truck haulage is the most widely used transportation system in surface mining.
Dump trucks carry fragmented ore/overburden from shovel or loader to:

• Waste dumps
  
• Crushers
  
• Stockpiles
  
• Conveyor loading points
  

Modern mining trucks (100–240 T) provide flexibility, high production, and reduced operational cost.

🔹 2. Types of Mining Trucks

2.1 Rear-Dump Trucks

Most common in surface mines.

• Payload: 60–240 T
  
• Excellent maneuverability
  
• Used with shovels/loaders
  

2.2 Bottom-Dump Trucks

• Dump through belly doors
  
• Used for spreading material on haul roads
  

2.3 Giant Off-Highway Trucks (Ultra-Class)Payload: 300–450 T
Used in mega-mines (iron ore, coal, copper).
2.4 Articulated Dump Trucks

• Tyre-mounted
  
• Used for rough terrain and small operations
  

🔹 3. Truck Selection Parameters

Key factors:

3.1 Payload CapacityMust match:

• Shovel bucket size
  
• Tonnage requirement
  
• Bench conditions
  

3.2 Engine Power

Higher HP → better gradient handling.

3.3 Body Capacity

Measured in m³ or tonnes.

3.4 Tyres

Largest cost component

• Tyre life = 3,000–6,000 hours
  
• Affected by road conditions
  

3.5 Dump HeightShould match shovel loading capability.
🔹 4. Shovel–Truck Matching

Optimal match ensures:

• Minimum idle time
  
• 3–5 passes per truck
  

Example:

Shovel Bucket	Truck Body
20 m³	100 T
35 m³	190 T
42 m³	240 T

🔹 5. Truck Cycle Time Components
Total Cycle Time = t_loading + t_haul + t_dump + t_return + delays

Typical Ranges:

• Loading: 1–2 min
  
• Hauling: 5–20 min (depends on distance)
  
• Dumping: 1–2 min
  
• Return: 5–20 min
  
• Delays: 10–15% allowance
  

🔹 6. Haul Road Design

6.1 Gradient

• Optimal: 8–10% (max)
  
• Affects speed & fuel consumption
  

6.2 Road WidthWidth=3×truck width\text{Width} = 3 \times \text{truck width}Width=3×truck width6.3 Superelevation

• Outer edge raised on curves
  
• Prevents skidding
  

6.4 Berms & Drainage

• Safety berms mandatory (DGMS)
  
• Proper water drainage to avoid slips
  

🔹 7. Truck Productivity CalculationQ=60×P×ηtcQ = \frac{60 \times P \times \eta}{t_c}Q=tc 60×P×ηWhere:

• P = Payload (tonnes)
  
• η = Efficiency (0.7–0.9)
  
• tc = Cycle time (minutes)
  

Example:Truck payload = 100 T
Cycle time = 20 min
Efficiency = 0.8Q=60×100×0.820=240 T/hrQ = \frac{60 \times 100 \times 0.8}{20} = 240 \, \text{T/hr}Q=2060×100×0.8 =240T/hr

🔹 8. Factors Affecting Truck Productivity

• Haul distance
  
• Gradient
  
• Road conditions
  
• Operator skill
  
• Shovel waiting time
  
• Tyre condition
  
• Weather
  

🔹 9. Diagram (Text Format)Truck Haul Cycle
Loading → Hauling → Dumping → Returning → (repeat)

🔹 10. Operational Delays

• Queue at shovel
  
• Queue at dump
  
• Tyre changes
  
• Fueling
  
• Breakdowns
  
• Weather delays
  

🔥  25 MCQs (DGMS Machinery Pattern)
1) Truck payload in large surface mines —

a) 5–10 T
b) 20–40 T
c) 100–240 T
d) 300–500 T
e) None
Answer: c
2) Shovel–truck ideal passes —

a) 1–2
b) 3–5
c) 8–10
d) 12–14
e) None
Answer: b
3) Cycle time includes —

a) Loading
b) Hauling
c) Dumping
d) Returning
e) All of these
Answer: e
4) Haul road gradient typically —

a) 2%
b) 4%
c) 8–10%
d) 15%
e) 25%
Answer: c
5) Productivity of truck depends on —

a) Drill diameter
b) Bench width
c) Cycle time
d) Explosive type
e) None
Answer: c
6) Major cost in truck haulage —

a) Diesel
b) Tyres
c) Operator
d) Oil
e) Air filters
Answer: b
7) Dumping time generally —

a) 15–20 min
b) 1–2 min
c) 5–10 min
d) 20–30 min
e) 40 min
Answer: b
8) Number of trucks required depends on —

a) Drill pattern
b) Shovel output
c) Coal grade
d) Pit slope
e) Ore density
Answer: b
9) Truck body size measured in —

a) moles
b) inches
c) tonnes or m³
d) psi
e) kWh
Answer: c
10) Wider roads increase —

a) Cost
b) Safety
c) Fuel
d) Bench height
e) Fragmentation
Answer: b
11) Queueing at shovel reduces —

a) Explosive cost
b) Bit wear
c) Productivity
d) Powder factor
e) None
Answer: c
12) Tyre life depends on —

a) Weather only
b) Blasting
c) Road conditions
d) Explosive type
e) Crusher
Answer: c
13) Dumping is done at —

a) Free face
b) Crusher
c) Waste dump
d) Stockpile
e) All of these
Answer: e
14) Articulated trucks used in —

a) Deep pits
b) Rough terrain
c) Coal shafts
d) Rivers
e) None
Answer: b
15) Truck engine power affects —

a) Drilling speed
b) Explosive loading
c) Gradient handling
d) Crusher input
e) None
Answer: c
16) Dump height should match —

a) Bench height
b) Sub-drill
c) Shovel dig height
d) Burden
e) None
Answer: c
17) Truck frame failures caused by —

a) Good road
b) Clean dumping
c) Poor maintenance & overload
d) Smooth benches
e) None
Answer: c
18) Cycle time is measured in —

a) m³
b) sec
c) minutes
d) hours
e) tonnes
Answer: c
19) Inefficient shovel positioning causes —

a) High VOD
b) More stemming
c) Truck idle time
d) Low drill speed
e) None
Answer: c
20) Fuel consumption increases with —

a) Flat roads
b) Steeper gradients
c) Tyre lubrication
d) Good blasting
e) High dilution
Answer: b
21) DGMS requires berm height to be —

a) 20 cm
b) 30 cm
c) Half tyre height
d) Bench height
e) None
Answer: c
22) Truck body capacity depends on —

a) Wheel speed
b) Bucket tooth size
c) Material density
d) Explosive velocity
e) None
Answer: c
23) More trucks than shovels cause —

a) High blasting cost
b) Shovel congestion
c) Less dump time
d) Oversize boulders
e) None
Answer: b
24) Truck operator skill affects —

a) Drill deviation
b) Cycle time
c) Fragment size
d) Blasting pattern
e) Bench height
Answer: b
25) The slowest leg of cycle time is often —

a) Loading
b) Dumping
c) Hauling
d) Swing-back
e) None
Answer: c
                          🔚 Conclusion

Truck haulage is a critical component of surface mine production.
Proper truck selection, haul road maintenance, and cycle-time optimization can reduce costs and increase mine output significantly.
Matching trucks with shovels ensures smooth, DGMS-compliant operation.

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