Dump trucks (also known as "tipping trucks" or "dump trucks") are widely used in mining, earthwork, construction, road construction, and municipal waste disposal due to their ability to lift and unload cargo containers. However, their structural characteristics, heavy-load operation, and unloading dynamics also pose significant safety risks. Driving stability is closely related to loading and unloading operations. This article aims to systematically review the key safety points of dump trucks during driving and loading and unloading operations from a professional perspective, and provide management and operational recommendations.
Before delving into the operating guidelines, it is necessary to first clarify the structural and stress differences between dump trucks and conventional cargo trucks, as well as the typical risks arising from these differences:
High center of gravity and high inertia: Dump trucks typically have a higher center of gravity when loaded than conventional flatbed trucks, making them more susceptible to rollover or overturning when driving or turning.
Sudden load fluctuations: During unloading, the load can drop momentarily, causing a sudden shift in the vehicle's weight distribution, which can easily lead to instability.
Lifting mechanism and power coupling: Lifting the cargo box typically relies on a hydraulic system, which places high demands on the oil circuits, seals, and structural strength. Improper operation or equipment failure can lead to loss of control or breakage.
Significant impact of terrain and road conditions: Roads on construction sites and mining areas are often uneven, steep, and have a weak roadbed, posing increased risks to heavily loaded vehicles.
Blind spots and human interference: Unloading sites are often filled with workers, machinery, and other vehicles. Blind spot management and on-site coordinated control are crucial.
Understanding these risk sources will help to more specifically address them in subsequent operating instructions.
The driving phase is the most fundamental phase of a dump truck and one of the most common areas where accidents (such as rollovers, rollovers, and collisions) occur. The following are key safety points:
2.1 Pre-trip Inspection and Preparation
Before you depart, you must be fully prepared to prevent potential hazards:
2.1.1 Pre-trip Inspection
The frame, body, and connecting parts must be free of cracks, deformation, or looseness.
Tires (including spare tires): tire pressure, wear, and cracks.
Braking system: main, auxiliary, Check if the parking brake is functioning properly.
Hydraulic system: Check for leaks in the lift cylinder, oil pipes, seals, and oil return lines.
Lubrication and fluids: Check for engine oil, transmission oil, hydraulic oil, radiator level, and cooling system.
Check if the lights, signals, reflective markings, and warning signs are functioning properly.
Check if the cab's instruments, alarm system, rearview mirrors, and cameras are functioning properly.
Check if the vehicle's structure (cargo box, tailgate) and locking mechanisms are reliable.
Check if additional mechanisms such as the differential lock and power take-off are reset or deactivated (to prevent accidental operation while driving).
Multiple national and industry guidelines emphasize the importance of immediate decommissioning and repair if the vehicle fails this inspection.
2.1.2 Route Planning and Terrain Assessment
Select a route with sufficient load capacity, appropriate slope, and reasonable turning radius.
Avoid soft, muddy, or pothole-prone sections or reinforce the roadbed.
Pre-identify obstacles along the route (power lines, bridge clearances, low structures, flooded sections, etc.).
If crossing bridges or passing through drainage ditches, assess whether the load and axle load exceed the specified standards.
2.1.3 Load Distribution and Securing
Before loading, ensure that the cargo is evenly distributed and symmetrically arranged.
Secure the cargo using baffles, partitions, anti-slip mats, or tie ropes or ballast bars to prevent shifting or sliding during travel.
For loose materials (sand, rocks, soil, etc.), cover with dust screens or canvas to reduce the risk of spillage.
Comply with national and regional regulations regarding vehicle load ratings and axle load limits. Do not overload the vehicle. Overloading is a common violation and significantly increases the risk of accidents.
2.2 Starting, Accelerating, and Shifting Controls
During the starting, accelerating, and shifting phases of a dump truck, operate it gently and avoid sudden movements, as this can easily cause dynamic load shock, slippage, or structural stress and strain:
When starting, gently apply the accelerator and avoid sudden acceleration. Avoid sudden accelerator application or abrupt clutch release when fully loaded.
When shifting, select the appropriate gear to match the engine speed (do not force up or down). When operating with a heavy load, shift gears in stages within the engine's braking force to avoid sudden speed changes.
When driving on undulating roads or slopes, maintain a steady speed and avoid repeated application of the accelerator or brakes.
2.3 Turning, Overtaking, Avoiding, and Braking
Heavy-loaded vehicles are at high risk during these dynamic maneuvers and require extreme caution:
When turning, slow down, maintain a straight line, and avoid sudden steering movements to prevent rollover.
Take a curve or widen the turning radius to avoid excessive load on the inside of the curve.
When overtaking or merging, carefully check your blind spots, traffic lights, and mirrors, and leave a buffer between yourself and others.
Maintain a sufficient distance from the vehicle behind you, especially on downhill or slippery roads.
Avoid sudden braking while driving to prevent the load from being thrust forward due to inertia and shifting unsecured cargo.
On downhill roads, use engine braking or lower gears as a braking aid whenever possible to avoid frequent braking, which can cause the brake system to overheat and fail.
2.4 Handling Special Conditions
Driving on Hills: When driving uphill, maintain a higher gear and avoid excessive downshifts. When driving downhill, use a lower gear to control speed and reduce reliance on the brakes.
Wet, slippery, On muddy roads: Slow down and maintain adequate steering margin. If the wheels slip, reduce the throttle and maintain stability, avoiding sudden braking.
At night, in fog, or in rain: Use low beams, width indicators, and hazard lights, control speed, and maintain safe distance between vehicles.
At intersections and on narrow roads: Slow down and sound the horn in advance, and be mindful of oncoming vehicles and pedestrians.
In multi-vehicle transport and oncoming traffic: Be aware of the pressure from oncoming vehicles and avoid the risk of overtaking when passing in narrow sections.
Unloading is one of the most challenging and dangerous stages of dump truck operation. Failure to be vigilant can easily lead to serious accidents such as rollovers, structural damage, and casualties.
3.1 Safety Precautions During Loading
While this article focuses primarily on driving and unloading, the loading phase is also part of the safety chain:
During loading, the vehicle must be stationary with the brakes locked, and the driver must monitor from a safe position;
When loading with a loader or forklift, avoid dropping heavy objects directly onto the container walls, drive shaft, or tailgate;
Avoid stacking heavy objects on one side near the container walls or tailgate to prevent excessive stress on one side;
Large objects (such as large rocks) should be lifted and positioned using a crane and should not be dropped directly from the loader;
After loading, check the cargo for loose items and any parts that require securing;
Multiple industry guidelines emphasize in their unloading safety manuals that "stability must be ensured before unloading."
3.2 Unloading Environment Requirements
Environmental preparation is essential before unloading:
3.2.1 Site Selection
Preferably select a flat, solid surface without loose or deformed surfaces.
Avoid unloading on slopes, potholes, soft soil, or side slopes.
If unloading on a slope, keep the vehicle's head downward to prevent a shift in center of gravity that could cause a rollover.
If the unloading site has boundaries (such as ditches, pit edges, retaining walls, etc.), maintain a safe distance from the vehicle.
Accounts show that many rollovers are caused by uneven surfaces or sideways unloading.
3.2.2 Clearing the Area and Isolating Personnel
The unloading area must be cleared, and personnel and equipment are prohibited from entering the unloading area.
Warning lines or safety warning signs should be set up where necessary.
Unloading operations should be coordinated by a signalman and monitoring personnel to ensure synchronization and prevent personnel from entering hazardous areas.
3.2.3 Stability Inspection
Check the cargo box's tailgate locking mechanism for integrity and smooth opening.
Ensure that the hydraulic hoses, cylinders, support arms, hinge points, and connecting pins are free of abnormal deformation or cracks.
If the carrier has an air suspension system, consider deploying the airbags and lowering the suspension height before unloading to enhance stability. Pik Rite's unloading safety manual recommends deploying the air suspension before lifting the cargo box.
3.3 Unloading Procedure and Risk Control
The following is a relatively standard unloading procedure, with key risk control points highlighted:
3.3.1 Confirming the Vehicle Position and Posture
Before unloading, position the vehicle in a straight line to avoid twisting.
If the ground is slightly tilted, correct this by slightly adjusting the wheels.
Ensure the vehicle's nose is facing downward (on a slope) or at least level.
3.3.2 Raising the Cargo Box and Lifting Operations
Start by slowly raising the cargo box to allow the cargo to initially move within the box.
Observe the cargo for signs of sticking, adhesion, or difficulty sliding.
If the cargo shows signs of abnormal tilt, sticking, or sinking on one side, immediately stop and lower the cargo box.
Once the cargo box has been raised to a certain angle, proceed to the main unloading phase.
Throughout the lifting process, ensure the load center remains within the vehicle frame rails to prevent the center of gravity from shifting beyond the specified limits and causing overturning.
3.3.3 Unloading and Lifting Dumping Materials
Material should slide smoothly to avoid sticking, getting stuck, or falling pieces impacting the tank walls.
For wet or sticky materials, auxiliary vibration, shock, or impact release may be necessary.
It is not recommended for anyone to enter the tank or perform auxiliary work while the vehicle is being lifted.
During the operation, the driver should remain in the cab, fasten their seat belt, and avoid jumping out of the vehicle or controlling the lift from outside. US guidelines clearly state that "do not exit the vehicle during unloading" is a key safety principle.
3.3.4 Lowering the Cargo Box
After all materials have been unloaded, slowly lower the cargo box back to the ground or its original position.
Avoid sudden impacts or collisions with the load-bearing structure during the lowering process.
If any abnormality occurs during the lowering process (such as a sudden drop in oil pressure, sticking, or unusual noise), immediately stop and inspect the operation.
3.3.5 Closing the Tailgate and Residual Material Removal
After unloading, close the tailgate promptly, ensuring the locking mechanism is secure.
If residual material adheres to the tailgate or the cargo box walls, clean it safely with tools (be careful not to stand under the cargo box or near the hinges).
Only depart the unloading area after confirming that there are no residual materials and no structural abnormalities.
Many industry safety guidelines consider "ground inspection before unloading, vehicle stability control during unloading, and no random operations after unloading" as basic requirements.
3.4 Typical Causes and Prevention of Improper Unloading Accidents
Combining accident cases with the safety manual, we can summarize several typical unloading risks and corresponding prevention and control measures:
|
Typical risks |
Causes/Inducements |
Preventive measures |
|
Overturning/tip-over during cargo box lifting |
The ground is uneven, tilted, the center of gravity of the cargo is offset, or the cargo is not parked in a straight line |
Select flat ground/downhill position, align the vehicle body, distribute the load evenly, and slowly ascend and observe |
|
Goods stuck or stuck |
High humidity, sticky materials, rough box walls |
Use liners, vibrating equipment, release inertia measures |
|
Structural failure/hydraulic leak |
Oil pipe rupture, seal damage, lifting overload |
Regular maintenance and inspection, replacement of aging parts, and strict avoidance of overloading |
|
Personnel injured by unloading |
Personnel enter the unloading area without any monitoring |
Clear the area, coordinate signals, and prohibit people from approaching |
|
Tailgate malfunction/projectile material injuring someone |
The lock fails, the tailgate is stuck, or it is hit by a strong impact |
Check the lock before unloading, use the buffer mechanism, and close the tailgate promptly after unloading |
In short, during the unloading phase, every action must be strictly controlled, the vehicle must be stable, and personnel management must be extremely cautious.
Operator safety awareness alone is often insufficient to completely prevent accidents. Systems and training are an effective "safety line of defense." The following are some suggestions:
4.1 Establishing Standard Operating Procedures (SOPs)
Develop a detailed dump truck operating manual for your company and project, including:
Pre-departure inspection checklist;
Control points during the driving phase;
Unloading site and operating procedures;
Emergency response procedures (such as lifting failure, rollover hazards, and cargo jams);
Demarcation of responsibilities and reporting procedures;
SOPs should be reviewed and updated regularly and posted prominently at fleet meetings or on the work site.
4.2 Training and Assessment Mechanism
Provide systematic training for drivers, including knowledge of vehicle structure, driving mechanics, safe operating procedures, and emergency response capabilities;
Implement regular skills assessments and refresher training, especially for new drivers;
Improve safety awareness and response capabilities through simulation training, case studies, and on-site operational drills;
Conduct post-incident analysis of accidents or dangerous situations, identify lessons learned, and incorporate them into training materials.
4.3 Maintenance and Inspection System
Establish a regular vehicle maintenance system, focusing on inspections of the hydraulic system, connecting pins, hinges, seals, locks, and braking systems;
Manage the service life of key components (such as lift cylinders, control valves, and oil pipes) and promptly replace aging parts;
Complete a vehicle inspection report before each trip and after each return to the factory. Any abnormalities must be repaired immediately;
Implement a patrol inspection and safety supervision system for fleets and projects to ensure compliance with procedures.
4.4 Safety Culture and Accountability Mechanism
Establish a culture of "safety first, prevention first";
Clearly define company, project, and Drivers and operators should share safety responsibilities and implement a reward and punishment mechanism;
Drivers and on-site personnel should be encouraged to proactively report potential hazards and violations;
For major projects or hazardous areas, third-party safety consultants or supervisory mechanisms can be introduced.
Dump truck driving, loading, and unloading operations are a highly coupled, risk-prone system. Comprehensive safety controls must be implemented across multiple dimensions, including vehicle structure, load layout, ground conditions, operating procedures, personnel management, and regulatory systems.
For engineering units, transportation companies, and operators, continuous improvement and advancement in technology, management, and training are the only way to ensure efficiency while minimizing accident risks.
We hope the above introduction has given you a better understanding of dump truck driving and loading operations. If you have any questions or would like to purchase dump trucks and accessories, please contact us.
