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CSCS Crawler Crane study materials
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CSCS Crawler Crane practice questions

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Question 1Crane types, components, and terminology

On a crawler crane, what is the primary function of the crawler track assembly?

  1. To provide the counterweight moment that balances the load
  2. To spread the machine's weight over a large ground area and allow travel under load Correct answer.
  3. To raise and lower the boom through a hydraulic cylinder
  4. To slew the upper works relative to the carbody

Explanation

Crawler tracks distribute the crane's weight and load reactions over a wide bearing area, reducing ground pressure and permitting movement while carrying a load. Boom hoisting, counterweighting, and slewing are performed by other, separate systems.

Question 2Crane types, components, and terminology

In lattice-boom crane terminology, what does the term 'boom butt' refer to?

  1. The pendant line that supports the boom
  2. The lowest boom section that connects to the boom foot or boom hinge Correct answer.
  3. The auxiliary jib offset bracket
  4. The tip sheave assembly at the top of the boom

Explanation

The boom butt is the base section of a lattice boom that pins to the boom foot on the rotating bed or boom hinge. The upper end is the boom tip, and the pendant lines are separate rigging components.

Question 3Crane types, components, and terminology

What is the purpose of the load moment indicator (LMI) on a crawler crane?

  1. To measure the tension in the boom pendant lines only
  2. To measure and display the load moment and warn or stop operation when the rated capacity is approached Correct answer.
  3. To indicate the wind speed at the boom tip
  4. To record engine hours for maintenance scheduling

Explanation

The LMI (also called rated capacity limiter) computes the load moment from boom geometry and load, compares it to the rated capacity chart, and provides warning and cutout functions. It is a rated-capacity device, not a maintenance or weather instrument.

Question 4Crane types, components, and terminology

Which component of a crawler crane transmits the load from the boom to the rotating bed?

  1. The swing bearing outer race
  2. The boom foot pins at the boom hinge Correct answer.
  3. The track roller frame
  4. The hoist drum clutch

Explanation

The boom foot is pinned at the boom hinge on the rotating bed, so boom thrust and moment reactions pass into the upper works through those pins. The swing bearing and track frames carry other reaction paths, and the hoist drum only manages rope.

Question 5Crane types, components, and terminology

A crane's capacity chart lists a 'rated capacity' for a given radius and boom length. What does rated capacity already account for?

  1. The weight of the counterweight package
  2. The deduction for the weight of the hook block and all lifting attachments Correct answer.
  3. The ground bearing pressure under the tracks
  4. The weight of the crane's carbody

Explanation

Rated capacity is the gross load minus the weight of the hook block, slings, and other lifting attachments, so the chart value is the maximum allowable load including rigging. Counterweight and carbody are part of the crane, and ground bearing pressure is a separate site consideration.

Question 6Crane types, components, and terminology

What is the function of the swing (slew) bearing on a crawler crane?

  1. To raise the boom to the required operating angle
  2. To allow the upper works to rotate relative to the carbody while carrying vertical and moment loads Correct answer.
  3. To tension the boom pendant lines
  4. To hold the track frames parallel during travel

Explanation

The swing bearing is a large rolling-element bearing that supports the rotating upper works and permits slewing while transferring vertical, moment, and horizontal loads to the carbody. It does not elevate the boom or tension pendants.

Question 7Crane types, components, and terminology

In crane terminology, what is 'boom angle'?

  1. The angle of the hook block relative to vertical
  2. The angle of the track frame to the ground
  3. The angle between the two pendant lines
  4. The angle between the boom centerline and the horizontal Correct answer.

Explanation

Boom angle is measured between the boom centerline and horizontal and is a key input to radius and capacity determination. Hook block attitude, pendant geometry, and track inclination are different measurements.

Question 8Crane types, components, and terminology

What distinguishes a lattice boom from a hydraulic telescopic boom on a crawler crane?

  1. A lattice boom cannot be fitted with a jib
  2. A lattice boom is assembled from pin-connected chord and lacing sections, while a telescopic boom extends by hydraulic sections Correct answer.
  3. A lattice boom has no capacity chart
  4. A lattice boom uses only hydraulic cylinders for elevation

Explanation

Lattice booms are built up from pinned sections of chords and lacing, whereas telescopic booms are nested hydraulic sections that extend. Both types can carry jibs and both require capacity charts.

Question 9Crane types, components, and terminology

What is the purpose of the boom hoist (boom winch) system?

  1. To travel the crane
  2. To swing the upper works
  3. To raise and lower the load on the hook
  4. To raise and lower the boom by reeling the boom hoist rope that acts through the pendant lines Correct answer.

Explanation

The boom hoist winch pays rope in or out to change boom angle, working through the boom pendant (guy) lines. Load hoisting, slewing, and travel are handled by separate systems.

Question 10Crane types, components, and terminology

A crane has a main boom of 100 ft and a fixed jib of 30 ft offset at 30 degrees. Which statement about the jib is correct?

  1. The jib has no effect on main boom capacity
  2. The jib increases capacity because it shortens the effective boom length
  3. The jib offset angle does not affect the load chart
  4. The jib reduces the allowable main boom capacity because its offset increases the effective radius and overturning moment Correct answer.

Explanation

A jib adds length, weight, and an offset that pushes the load line further out, increasing radius and overturning moment, so the load chart for the jib configuration governs and typically reduces allowable load. Jib offset angle is a chart variable.

Question 11Crane types, components, and terminology

What is the 'counterweight' on a crawler crane and where is it located?

  1. Ballast carried inside the track frames
  2. The weight of the boom itself
  3. Steel blocks placed under the tracks to increase ground bearing
  4. Heavy removable plates mounted on the rear of the rotating upper works to balance the load moment Correct answer.

Explanation

Counterweight consists of heavy plates or slabs mounted at the rear of the rotating bed to provide a balancing moment against the lifted load. It is part of the upper works, not the undercarriage or boom.

Question 12Crane types, components, and terminology

What does the term 'working radius' mean in crawler crane operation?

  1. The vertical height of the boom tip above ground
  2. The distance from the boom foot to the boom tip
  3. The length of the load line paid out
  4. The horizontal distance from the crane's rotation center to the centerline of the load Correct answer.

Explanation

Working radius is measured horizontally from the slewing center to the load line, and it is the value read on the capacity chart. Boom length, tip height, and rope payout are different quantities.

Question 13Crane types, components, and terminology

What is the role of the 'boom stop' on a lattice-boom crawler crane?

  1. To hold the track frames in alignment during travel
  2. To stop the swing when the crane reaches a set angle
  3. To limit the maximum load on the hook
  4. To prevent the boom from being raised past its maximum angle and to cushion the boom if it falls back Correct answer.

Explanation

Boom stops are structural or hydraulic devices that limit maximum boom elevation and absorb energy if the boom falls backward. They are not load-limiting or swing-limiting devices.

Question 14Crane types, components, and terminology

A crawler crane is fitted with a 'luffing jib' rather than a fixed jib. What is a defining characteristic of a luffing jib?

  1. It eliminates the need for a load moment indicator
  2. It is welded permanently to the boom tip
  3. It can only be used with a hydraulic telescopic boom
  4. Its angle can be changed independently of the main boom using separate luffing pendants and a luffing hoist Correct answer.

Explanation

A luffing jib is articulated at the boom tip and its angle is adjusted by its own luffing rope and pendants, allowing the radius to be varied. It is not permanent, not restricted to telescopic booms, and still requires an LMI.

Question 15Crane types, components, and terminology

What is the function of the 'tagline' in a crawler crane lift?

  1. To hold the boom at a fixed angle
  2. To carry the load's weight along with the main hoist line
  3. To control load rotation and swing by restraining the load with a hand-held or mechanical line Correct answer.
  4. To measure the load moment

Explanation

A tagline is a separate rope used by the rigging crew or a mechanical device to control load rotation and sway. It does not support load weight, measure moment, or fix boom angle.

Question 16Crane types, components, and terminology

A crane's load chart shows a capacity of 40,000 lb at a 20 ft radius and 25,000 lb at a 30 ft radius with the same boom. What is the best interpretation?

  1. Capacity is independent of radius for a fixed boom length
  2. Allowable capacity decreases as radius increases because the overturning moment increases Correct answer.
  3. The 30 ft value is limited only by hoist rope strength
  4. Allowable capacity increases with radius because the boom is more vertical

Explanation

As radius grows, the load moment about the tipping axis increases, so allowable load falls. Structural and stability limits are both reflected in the chart, and capacity is not independent of radius.

Question 17Crane types, components, and terminology

What is meant by 'parts of line' in crane rigging terminology?

  1. The number of rope falls supporting the load between the boom tip sheaves and the hook block Correct answer.
  2. The number of boom sections in the lattice
  3. The number of track rollers per side
  4. The number of pendant lines supporting the boom

Explanation

Parts of line is the number of rope falls between the boom tip and hook block, which divides the load among the falls and affects line pull and line speed. It is unrelated to boom sections, pendants, or track rollers.

Question 18Crane types, components, and terminology

On a crawler crane, what is the 'carbody'?

  1. The lower structure that connects the track frames and supports the swing bearing Correct answer.
  2. The operator's cab enclosure
  3. The boom tip sheave assembly
  4. The rotating platform that carries the boom and counterweight

Explanation

The carbody is the lower non-rotating structure to which the track frames attach and on which the swing bearing and upper works sit. The rotating platform, boom tip, and cab are separate parts of the machine.

Question 19Crane types, components, and terminology

A crane is configured with a boom length of 120 ft and a boom angle of 60 degrees. Approximately what is the horizontal radius from the boom foot to the boom tip, ignoring boom deflection?

  1. About 104 ft
  2. About 30 ft
  3. About 120 ft
  4. About 60 ft Correct answer.

Explanation

Horizontal projection equals boom length times the cosine of the boom angle: 120 ft × cos 60° = 120 × 0.5 = 60 ft. The other values correspond to different trigonometric relationships or to the full boom length.

Question 20Crane types, components, and terminology

What is the purpose of the 'anti-two-block' device on a crawler crane?

  1. To prevent the counterweight from striking the carbody
  2. To prevent the hook block from contacting the boom tip by stopping hoist-up or boom-down motion Correct answer.
  3. To prevent the boom from contacting the ground during lowering
  4. To limit the number of parts of line

Explanation

The anti-two-block device senses proximity between the hook block and boom tip and interrupts the dangerous motion (hoist up or boom down) before contact occurs. It does not govern parts of line or counterweight travel.

Question 21Crane types, components, and terminology

What is 'boom deflection' and why is it significant in capacity calculations?

  1. Elastic stretch of the hoist rope that raises the hook
  2. Movement of the counterweight on its mounting
  3. Settling of the tracks into the ground
  4. Bending of the boom under load that increases actual radius beyond the geometric value, reducing capacity Correct answer.

Explanation

Under load, the boom bends, which pushes the load line further out and increases actual radius compared with the geometric radius. Load charts account for this, and operators must recognize that actual radius can exceed the calculated value.

Question 22Crane types, components, and terminology

In crawler crane terminology, what is a 'superlift' or 'counterweight trailer' arrangement?

  1. An additional counterweight carried on a separate trailing or suspended attachment to increase capacity at long radii Correct answer.
  2. A ground anchor for the boom pendant lines
  3. A trailer used to transport the boom sections
  4. A second crane used to assist the main crane

Explanation

Superlift systems add counterweight on an independent trailing or suspended carrier, increasing the resisting moment and allowing higher capacities at long radius. They are not assist cranes, transport trailers, or ground anchors.

Question 23Crane types, components, and terminology

What does the term 'chord' refer to in a lattice boom section?

  1. The sheave at the boom tip
  2. The diagonal lacing members between corners
  3. The main longitudinal structural members at the corners of the boom section Correct answer.
  4. The pin connecting two boom sections

Explanation

Chords are the primary longitudinal members running the length of each lattice section at the corners, carrying the main bending and axial loads. Lacing members are the diagonals, and pins and sheaves are separate components.

Question 24Crane types, components, and terminology

A crane is rated 30,000 lb at a 25 ft radius with 15,000 lb of counterweight. If counterweight is removed for transport and not reinstalled, what is the most accurate statement about the capacity chart?

  1. Capacity remains the same because counterweight only affects travel stability
  2. The published chart no longer applies because it assumes the specified counterweight is installed Correct answer.
  3. Capacity is governed only by boom strength, not counterweight
  4. Capacity increases because the crane is lighter

Explanation

Load charts are valid only for the exact configuration, including specified counterweight. Removing counterweight reduces the resisting moment and invalidates the chart, so the crane must not be operated to the published capacities.

Question 25Site and ground conditions, setup, and stability

Before a crawler crane is walked onto a prepared working pad, which condition most directly governs whether the pad can carry the crane's ground bearing pressure?

  1. The crane's boom length in the transport configuration
  2. The pad's surface color and drainage markings
  3. The bearing capacity of the underlying soil or engineered fill Correct answer.
  4. The number of track shoes in contact with the pad

Explanation

Ground bearing pressure from the tracks must be compared with the allowable bearing capacity of the soil or engineered fill beneath the pad. Surface appearance and boom configuration do not determine whether the ground can support the load. Track shoe count affects contact area but not the soil's capacity.

Question 26Site and ground conditions, setup, and stability

A crawler crane is set up on a slope. What is the primary stability concern compared with a level setup?

  1. A raised center of gravity and a component of load acting downslope Correct answer.
  2. Increased hydraulic oil temperature
  3. Reduced effective counterweight radius
  4. Faster boom hoist speed

Explanation

On a slope the crane's center of gravity shifts and part of the load and machine weight acts downslope, reducing the tipping margin. Leveling the crane is normally required by the manufacturer before lifting. Oil temperature and hoist speed are unrelated to slope stability.

Question 27Site and ground conditions, setup, and stability

When planning a lift near an excavation, what is the standard minimum setback for the crawler crane's tracks from the edge of the excavation?

  1. Determined by a competent person based on soil type and excavation depth Correct answer.
  2. Always exactly 3 m from the edge
  3. Twice the track width regardless of soil
  4. Always exactly 1 m from the edge

Explanation

Setback from an excavation edge depends on soil type, depth, and the surcharge imposed by the crane, and must be assessed by a competent person. Fixed distances cannot cover all soil and depth conditions. The setback protects against slope failure under the crane's load.

Question 28Site and ground conditions, setup, and stability

Which document typically specifies the allowable out-of-level tolerance for a crawler crane during setup?

  1. The manufacturer's operator manual Correct answer.
  2. The project's waste disposal permit
  3. The site's traffic management plan
  4. The crane's annual tax certificate

Explanation

The manufacturer's operator manual states the permissible out-of-level tolerance for setup and operation. Site plans and administrative documents do not define machine tolerances. Exceeding the manufacturer's tolerance can reduce capacity and stability.

Question 29Site and ground conditions, setup, and stability

A crawler crane must travel with a suspended load across a site. Which practice best preserves stability?

  1. Keep the load as high as possible to clear obstacles
  2. Travel at maximum track speed to reduce exposure time
  3. Raise the boom to maximum angle before moving
  4. Keep the load close to the ground and within the manufacturer's travel capacity limits Correct answer.

Explanation

Traveling with a load requires keeping it low and within the manufacturer's specified travel capacity, which is typically lower than the static lifting capacity. High load height or speed increases dynamic effects and tipping risk. Boom angle changes must follow the load chart, not be maximized arbitrarily.

Question 30Site and ground conditions, setup, and stability

What is the purpose of using crane mats under crawler tracks on soft ground?

  1. To provide a level reference for the boom angle indicator
  2. To reduce track wear during travel
  3. To increase the crane's lifting capacity
  4. To spread the load over a larger area and reduce ground bearing pressure Correct answer.

Explanation

Mats distribute the track load over a larger footprint, lowering the pressure applied to the soil. This helps prevent settlement and bearing failure. Mats do not increase the crane's rated capacity or set boom angle references.

Question 31Site and ground conditions, setup, and stability

During setup, the crane's outriggers or track pads are found to be over a buried utility. What is the most appropriate action?

  1. Relocate the crane or protect the utility per an engineered plan before setup Correct answer.
  2. Place a single timber under the track and continue
  3. Reduce the load by 10 percent and continue
  4. Proceed if the utility is marked on a drawing

Explanation

Buried utilities can be damaged or collapse under crane loads, so the crane must be relocated or the utility protected according to an engineered plan. A drawing alone does not confirm the utility can carry the load. Arbitrary load reductions or single timbers do not provide adequate protection.

Question 32Site and ground conditions, setup, and stability

Which factor most affects the crane's stability when the boom is swung over the side of the tracks versus over the ends?

  1. The direction of the wind relative to the cab
  2. The engine RPM during the swing
  3. The track gauge and the resulting tipping axis Correct answer.
  4. The color of the load being lifted

Explanation

Crawler crane capacity varies with the position of the load relative to the tracks because the tipping axis changes with track gauge and length. Side loading typically has a shorter tipping axis than end loading. Wind, load color, and engine RPM do not define the tipping axis.

Question 33Site and ground conditions, setup, and stability

A crane is set up adjacent to a recently backfilled trench. Why should the setup be evaluated by a competent person?

  1. Backfill always increases the soil bearing capacity
  2. Backfill eliminates the need for crane mats
  3. Trench walls always protect the crane from wind
  4. Backfill may be less consolidated and unable to support the track loads Correct answer.

Explanation

Recent backfill may not be compacted to the same density as native soil and can settle or fail under track loads. A competent person must assess whether the ground can support the crane. Backfill does not inherently increase capacity or remove the need for mats.

Question 34Site and ground conditions, setup, and stability

What is the primary reason for leveling a crawler crane before making a lift?

  1. To reduce track chain wear
  2. To reduce fuel consumption
  3. To improve the operator's visibility
  4. To keep the load chart valid and maintain the designed stability margin Correct answer.

Explanation

Crane load charts assume the machine is level within the manufacturer's tolerance. Operating out of level invalidates the chart and reduces the stability margin. Fuel use, visibility, and track wear are not the primary reasons for leveling.

Question 35Site and ground conditions, setup, and stability

Which ground condition is most likely to require an engineered foundation rather than simple timber mats for a crawler crane setup?

  1. Dry dense sand
  2. Weathered rock with a level surface
  3. Soft clay with a high water table Correct answer.
  4. Firm compacted gravel

Explanation

Soft clay with a high water table has low bearing capacity and is prone to settlement and bearing failure, often requiring an engineered foundation. Firm gravel, dense sand, and level rock generally provide adequate support with conventional mats.

Question 36Site and ground conditions, setup, and stability

When a crawler crane is assembled, which item should be confirmed against the load chart before the first lift?

  1. The counterweight configuration and boom length installed Correct answer.
  2. The number of personnel on site
  3. The color of the rigging tags
  4. The type of fuel in the tank

Explanation

The load chart is specific to the counterweight configuration, boom length, and other crane geometry. Confirming these match the chart ensures the rated capacities apply. Rigging tag color, personnel count, and fuel type do not affect chart validity.

Question 37Site and ground conditions, setup, and stability

A crawler crane will be operated on a site where the ground freezes and thaws overnight. What stability issue should be anticipated?

  1. Higher hydraulic pressure
  2. Reduced boom length
  3. Loss of bearing capacity as thawed soil softens Correct answer.
  4. Increased track friction

Explanation

Freeze-thaw cycles can soften soil and reduce its bearing capacity, causing settlement under the tracks. Setup should be re-evaluated as conditions change. Track friction, boom length, and hydraulic pressure are not the primary freeze-thaw stability concern.

Question 38Site and ground conditions, setup, and stability

Which action best manages the risk of the crane tipping during a swing over the corner of the tracks?

  1. Add counterweight beyond the manufacturer's specification
  2. Refer to the load chart for the specific quadrant and radius Correct answer.
  3. Increase swing speed to pass the corner quickly
  4. Lower the boom to horizontal

Explanation

Capacity varies by quadrant and radius, so the load chart for the specific configuration must be used. Increasing speed or lowering the boom does not increase capacity. Adding counterweight beyond specification can overload the crane structure and is not permitted.

Question 39Site and ground conditions, setup, and stability

What should be done if the ground beneath a crawler crane shows signs of settlement during a lift?

  1. Stop the lift, lower the load, and reassess the ground support Correct answer.
  2. Continue the lift and monitor after completion
  3. Increase engine RPM to complete the lift faster
  4. Shift the load to the opposite side of the tracks

Explanation

Settlement indicates the ground may be failing, so the lift must stop and the load lowered before reassessing support. Continuing or speeding up the lift increases the risk of tipping. Shifting the load does not correct a failing foundation.

Question 40Site and ground conditions, setup, and stability

Which of the following best describes the term 'ground bearing pressure' for a crawler crane?

  1. The pressure inside the track tensioning cylinder
  2. The pressure in the boom hoist circuit
  3. The pressure required to lift the load
  4. The pressure the crane's tracks exert on the ground beneath them Correct answer.

Explanation

Ground bearing pressure is the load per unit area that the tracks impose on the supporting ground. It must be compared with the soil's allowable bearing capacity. The other options describe hydraulic or lifting pressures unrelated to soil support.

Question 41Site and ground conditions, setup, and stability

A crane must be set up on a site with overhead power lines nearby. Which setup consideration is most relevant to stability planning?

  1. The required approach distance and any de-energizing or barriers Correct answer.
  2. The color of the line markers
  3. The type of conductor material
  4. The number of insulators on the pole

Explanation

Overhead lines require maintaining the specified approach distance, and where that cannot be achieved, de-energizing or barriers are needed. These constraints can dictate where the crane can be positioned and thus affect setup planning. Line color, insulator count, and conductor material do not define the safe approach.

Question 42Site and ground conditions, setup, and stability

Why is it important to verify the crane's actual track pressure against the mat's rated capacity?

  1. To set the engine idle speed
  2. To determine the boom length needed
  3. To confirm the mat color matches site markings
  4. To ensure the mat does not crush or punch through into soft soil Correct answer.

Explanation

Mats must be strong enough to carry the track pressure without crushing or punching into the soil, which would concentrate load and reduce support. Mat color, boom length, and idle speed are unrelated to mat capacity.

Question 43Site and ground conditions, setup, and stability

Which condition would most likely require the crane to be repositioned rather than merely adding mats?

  1. A slightly uneven surface finish
  2. A shallow puddle on the pad
  3. Loose gravel on the surface
  4. A known void or culvert beneath the setup area Correct answer.

Explanation

A void or culvert beneath the setup can collapse under crane loads and cannot be reliably fixed with mats alone, so repositioning or engineered protection is needed. Surface finish, puddles, and loose gravel are typically manageable with preparation and mats.

Question 44Site and ground conditions, setup, and stability

What is the role of a lift plan regarding ground conditions?

  1. It replaces the need for a competent person
  2. It lists the crane's maintenance history
  3. It records only the load weight
  4. It documents the assessed ground support, crane position, and capacity checks Correct answer.

Explanation

A lift plan documents the assessed ground conditions, crane position, and capacity checks so the lift can be performed safely. It does not replace the competent person's assessment or serve as a maintenance record. Load weight is only one input.

Question 45Site and ground conditions, setup, and stability

A crawler crane is set up near a slope crest. What is the main stability risk?

  1. The crane's boom may become too short
  2. The slope may fail under the crane's surcharge load Correct answer.
  3. The load chart may change color
  4. The tracks may become too clean

Explanation

A crane near a slope crest imposes a surcharge that can trigger slope failure, leading to loss of support and tipping. Boom length, track cleanliness, and chart appearance are not slope stability concerns. Setback and slope stability assessment are required.

Question 46Site and ground conditions, setup, and stability

Which practice is appropriate when blocking under a crawler crane track to level it?

  1. Use sand bags only
  2. Use loose bricks stacked to the required height
  3. Use engineered blocking sized for the load and secured against displacement Correct answer.
  4. Use a single round log under the track

Explanation

Blocking must be engineered for the load and secured so it cannot displace or crush under the track. Loose bricks, round logs, and sand bags alone can shift or fail. Stable, load-rated blocking maintains level and support.

Question 47Site and ground conditions, setup, and stability

What does the term 'surcharge' refer to in the context of crane setup near an excavation?

  1. The extra cost of crane rental
  2. The extra load imposed on the ground by the crane and its lifted load Correct answer.
  3. The additional counterweight added by the operator
  4. The overload alarm on the crane

Explanation

Surcharge is the additional load the crane and its load place on the soil near an excavation, which can reduce slope stability. It is not an operator-added counterweight, a rental cost, or an alarm. Surcharge must be considered in setback planning.

Question 48Site and ground conditions, setup, and stability

Which condition should prompt a re-evaluation of ground support after the crane has been set up?

  1. A change in the operator's shift
  2. A change from dry weather to heavy rainfall Correct answer.
  3. A change in the load's color
  4. A change in the crane's horn volume

Explanation

Heavy rainfall can soften and weaken soil, reducing bearing capacity and slope stability, so ground support should be re-evaluated. Operator shift changes, load color, and horn volume do not affect ground conditions.

Question 49Site and ground conditions, setup, and stability

When a crawler crane is configured with a long boom, how does this generally affect setup planning for ground conditions?

  1. The crane no longer needs mats
  2. Ground support requirements decrease because the boom is lighter
  3. Ground support requirements are unaffected by boom length
  4. Ground support must account for the changed load distribution and reactions Correct answer.

Explanation

Boom length changes the crane's geometry and the reactions at the tracks, so ground support planning must reflect the actual configuration. Longer booms do not reduce support needs or eliminate mats. Ground support is not independent of boom configuration.

Question 50Site and ground conditions, setup, and stability

Which document typically states the maximum allowable ground bearing pressure that a crane's supporting surface must be able to withstand?

  1. The project's traffic management plan
  2. The manufacturer's crane operator manual and load chart notes Correct answer.
  3. The site's daily lift schedule
  4. The delivery ticket for the crane counterweights

Explanation

The crane manufacturer publishes track bearing pressure and permissible support requirements in the operator manual and load chart notes, and the lift plan must be built around those values. Site logistics and delivery paperwork do not define structural ground limits.