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Questions and Answers
What is the primary calculation used to determine production in cubic yards per hour?
What is the primary calculation used to determine production in cubic yards per hour?
What does a bucket fill factor of 0.95 indicate in excavation?
What does a bucket fill factor of 0.95 indicate in excavation?
Which type of truck is designed to operate over soft ground?
Which type of truck is designed to operate over soft ground?
What is the estimated cycle time given in the example provided for the excavating operation?
What is the estimated cycle time given in the example provided for the excavating operation?
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Which of the following is NOT a method of dumping for trucks?
Which of the following is NOT a method of dumping for trucks?
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What is a primary advantage of a wheel-type dozer compared to a crawler dozer?
What is a primary advantage of a wheel-type dozer compared to a crawler dozer?
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What equipment is standard for excavating operations?
What equipment is standard for excavating operations?
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What type of blade is used for land clearing with dozers?
What type of blade is used for land clearing with dozers?
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What is the purpose of a rear-mounted ripper on a dozer?
What is the purpose of a rear-mounted ripper on a dozer?
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Which factor is NOT considered in calculating dozer production estimates?
Which factor is NOT considered in calculating dozer production estimates?
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Which dozer operation involves side-by-side placements?
Which dozer operation involves side-by-side placements?
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What influences the efficiency factor in dozer production?
What influences the efficiency factor in dozer production?
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What is the formula to calculate production for a dozer?
What is the formula to calculate production for a dozer?
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What is the maximum lifting capacity of a lattice-boom truck-mounted crane at 23 ft?
What is the maximum lifting capacity of a lattice-boom truck-mounted crane at 23 ft?
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What is the typical maximum boom length of telecoping-boom truck-mounted cranes?
What is the typical maximum boom length of telecoping-boom truck-mounted cranes?
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Which feature is characteristic of rough-terrain cranes?
Which feature is characteristic of rough-terrain cranes?
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What is the purpose of the curved ejector top in an ejector?
What is the purpose of the curved ejector top in an ejector?
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Which factor is NOT considered in scraper selection?
Which factor is NOT considered in scraper selection?
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What is the maximum travel speed of lattice-boom truck-mounted cranes?
What is the maximum travel speed of lattice-boom truck-mounted cranes?
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What is the typical minimum radius for most models of telescoping-boom truck-mounted cranes?
What is the typical minimum radius for most models of telescoping-boom truck-mounted cranes?
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What is the difference between Heaped Capacity and Struck Capacity in load estimation?
What is the difference between Heaped Capacity and Struck Capacity in load estimation?
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What determines the Fill Factor of a loader's bucket?
What determines the Fill Factor of a loader's bucket?
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What is a common application of front shovels?
What is a common application of front shovels?
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How often does a shovel typically need to move during its operation?
How often does a shovel typically need to move during its operation?
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What is crucial for bucket penetration in hydraulic hoes?
What is crucial for bucket penetration in hydraulic hoes?
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What aspect of operational efficiency is enhanced by keeping the bowl low in hauling?
What aspect of operational efficiency is enhanced by keeping the bowl low in hauling?
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What hand signal indicates to raise the load slowly?
What hand signal indicates to raise the load slowly?
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Which of the following signals indicates to lower the boom?
Which of the following signals indicates to lower the boom?
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What does the hand signal consisting of both arms outstretched, fingers clenched and thumbs pointing inward indicate?
What does the hand signal consisting of both arms outstretched, fingers clenched and thumbs pointing inward indicate?
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What should a signal person wear to ensure they are visible while directing a crane operation?
What should a signal person wear to ensure they are visible while directing a crane operation?
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What should be done if there are three seconds of radio silence during a crane operation?
What should be done if there are three seconds of radio silence during a crane operation?
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What is the vertical movement of the load in crane terminology?
What is the vertical movement of the load in crane terminology?
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What movement allows for the adjustment of the operating radius of a crane?
What movement allows for the adjustment of the operating radius of a crane?
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Where is the slewing ring located in a fixed tower-type crane?
Where is the slewing ring located in a fixed tower-type crane?
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Which of the following configurations does not use pendants?
Which of the following configurations does not use pendants?
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What is the function of the counterweight in a crane?
What is the function of the counterweight in a crane?
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What allows for the rotation of the jib around the tower's vertical axis?
What allows for the rotation of the jib around the tower's vertical axis?
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What is the primary role of the operator cab in a tall tower crane?
What is the primary role of the operator cab in a tall tower crane?
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What does the hoist cable run through on its way to the hook?
What does the hoist cable run through on its way to the hook?
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Study Notes
Dozers
- Crawler (tracklaying) dozers are the workhorses of the construction industry.
- Dozers are designed for high drawbar pull and tractive effort.
- Crawler dozers exert low ground-bearing pressure, increasing versatility.
- Dozers, tractors equipped with a blade are standard excavating equipment.
- Dozers with special clearing blades are used for land clearing.
- Dozers equipped with push blades or blocks assist scrapers loading materials.
- A dozer can have a rear-mounted ripper for loosening and breaking up rock.
- Blade adjustments include tilting, C-frame blade mount (outside/inside the tracks) and blade angle.
- Pitch is also a type of blade adjustment.
- Dozer production estimates include ideal production based on manufacturer's charts or figures, grade correction (using reference tables), material-weight correction, operator skill, GPS and computer graphics factors, material-type correction (e.g., clay, sand, loam), operating technique (slot dozing, side-by-side dozing), visibility, efficiency factor, material conversion if required, and total operating hours required.
Scrapers
- Dozers are used for short hauls (less than 300 ft).
- Scrapers are used for medium hauls (up to 3,000 ft).
- Scrapers are effective for shot rock, ripped rock, earth/rock mix, gravel, sand, silt, and clay.
- Scrapers can be conventional (push-loaded) or elevating, depending on conditions
- Conventional scrapers are uneconomical when haul grades are greater than 5% and return grades are greater than 12%.
- Elevating scrapers are suitable for short hauls and favorable materials.
- Elevating scrapers cost more to operate and purchase than their conventional counterparts. An elevator adds weight and requires more power.
Loaders/Shovels/Hydraulic Excavators
- Loaders can be equipped with various bucket sizes and types.
- Buckets are rated for heaped and struck capacities.
- Heaped capacity is the primary rating for production estimating.
- The fill factor adjusts heaped capacity in loose cubic yards.
- Front shovels are used for hard digging above track level and loading haul units.
- A typical shovel has a mounting (substructure), boom, stick, and bucket.
- Shovel production estimates involve measuring cycles per hour, swing-depth factor, bucket volume, fill factor, and job efficiency.
- Hydraulic excavators are multipurpose tools used in different applications.
- Hydraulic excavators have a hoe that swings downward, useful for digging below running gear.
- Modern hydraulic excavators can be equipped with other attachments.
- These excavators are either track-mounted or wheel-mounted.
- Load capacity depends on the quadrant position of the boom.
Draglines & Clamshells
- Draglines are typically cable-operated.
- Clamshells can be either cable- or hydraulic-operated.
- Draglines' reach is longer than that of clamshells.
- Production estimates for draglines and clamshells should incorporate factors like machine size, swing angle, average depth of cut, material properties, job efficiency, and soil swell.
Trucks/Hauling Equipment
- Trucks are classified by their method of dumping (rear, bottom, side, conveyor).
- Trucks are also classified by frame type (rigid or articulated) and engine type (gasoline, diesel, propane).
- Additional truck classification criteria include drive configuration (2-, 4-, 6-wheel) and transmission type (direct or diesel-electric).
- Truck capacity is either gravimetric (tons) or volumetric (cubic yards).
- Distance is important when choosing the right truck for a particular haul.
Tower Cranes
- Tower cranes are extremely versatile.
- These cranes are flexible, enabling load pick-up and positioning in multiple planes.
- Tower cranes have an advantage in that both the operator and jib are typically above ground level and the work area.
- Tower cranes are constructed with a fixed base, which can be either free-standing or braced to the structure.
- Different types of tower cranes include: flattop or topless tower cranes, luffing jib cranes, and others.
- Tower crane components include the saddle jib, pendant, cat-head, counter jib, trolley, hook block, hoisting, and slewing.
- Lifting height, radius, hoisting speed, mounting configurations, and crane size can determine selection factors.
- A crane is a complex machine with many moving parts that require specific considerations for safe operation.
General
- Safety is critical for operation of any equipment.
- Operators must be competent—with training and proficiency.
- Understand the machine's specifications.
- Check the manufacturer's load charts, and follow instructions, including safety measures.
- Ensure that the crane can safely perform each specific lift based on its parameters.
- Various safety factors, including clear space for movement, should be observed.
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Description
Test your knowledge on excavation techniques and dozer operations with this quiz. Explore topics such as production calculations, equipment types, and operational efficiency. Ideal for students and professionals in construction and civil engineering.