EARTHMOVING (Chap 5) Flashcards
involves moving soil or rock to
meet construction needs and modifying it to meet construction requirements. Activities include excavation, loading, hauling, placing, compacting, grading, and finishing. Efficient management requires accurate estimating, equipment selection, and competent job management.
Earth moving
KEY ACTIVITIES:
______: Removing soil or rock from its natural location using machines like
excavators or bulldozers.
______: Placing excavated material into hauling equipment such as dump trucks
or loaders.
______: Transporting the material to its destination using trucks, dump trailers,
or other vehicles.
______: Dumping and spreading the material in its final location.
Excavation, Loading, Hauling, Placing
KEY ACTIVITIES:
______: Compressing the material to achieve desired density and stability
using rollers or vibratory equipment.
______: Smoothing and leveling the surface to create the desired shape and
grade.
______: Applying final touches to the surface, such as paving or landscaping
Compacting, Grading, Finishing
(DESIGNING STAGE)
GENERAL SOIL CHARACTERISTICS:
______: Measured in pounds per cubic yard or kilograms per cubic meter. It depends on soil type, moisture content, and compaction. It relates to bearing capacity and haul unit capacity.
______: The percentage of water in a soil, calculated as
(moist weight - dry weight) / dry weight * 100.
Unit Soil Weight, Moisture Content
(DESIGNING STAGE)
GENERAL SOIL CHARACTERISTICS:
______: The ability of a soil to support vehicle weight under repeated traffic. It affects access roads and equipment
operations.
______: Impacts trafficability and drying ease.
______: The difficulty of excavating and loading a soil.
Granular soils are easy, cohesive soils and rock are difficult.
Trafficability, Soil Drainage, Loadability
SOIL - VOLUME CHANGE CHARACTERISTICS
______: Material in its natural state, measured in bank cubic yards (BCY) or bankcubic meters (Bm^3).
______: Material after excavation or loading, measured in loose cubic yards (LCY)
or loose cubic meters (Lm^3).
______: Material after compaction, measured in compacted cubic yards
(CCY) or compacted cubic meters (Cm^3).
Bank, Loose, Compacted
SOIL - VOLUME CHANGE CHARACTERISTICS
______: When soil is excavated, it increases in volume due to loosened grains and
air filling voids. This is called swell.
______: The ratio of compacted volume to bank volume, which
accounts for the decrease in volume during compaction.
Swell, Shrinkage Factor
FACTORS INFLUENCING EARTH MOVING
______: The type, condition, and volume of the material significantly affect the equipment and methods used.
* Site Conditions: The topography, accessibility, and proximity to haul routes influence the efficiency of earthmoving operations.
______: The desired shape, grade, and compaction levels determine the specific tasks and equipment needed.
______: Compliance with local regulations regarding erosion control, waste disposal, and noise pollution is essential.
Soil and Rock Properties, Project Requirements, Environmental Regulations
ENVIRONMENTAL CONSIDERATIONS
______: Measures like silt fences, erosion blankets, and revegetation are used to prevent soil erosion.
______: Proper disposal of excavated materials and debris is essential to comply with environmental
regulations.
______: Mitigation measures such as water spraying, noise barriers, and limiting operating hours may be required.
Erosion Control, Waste Management, Noise and Dust Control
EXCAVATING AND LIFTING EQUIPMENT
are power-driven digging machines used in earthmoving operations.
Excavators
Hydraulic excavator
* Cable-operated crane-shovel family
(shovels, draglines, hoes, and
clamshells)
* Dozers, loaders, and scrapers
Major Types of Excavators
operate heavy equipment to move, load, and grade earth, rock, gravel or other materials during construction. They are entirely reliant onhydraulic systems, with the chassis rotating 360 degrees and controlling the independent
boom and bucket.
Advantages over cable-operated excavators
* faster cycle time * more precise digging
* higher bucket penetrating force * easier operation control
hydraulic excavators
In 1836, William S. Otis developed a
machine that mechanically duplicated
the motion of a man digging with a
hand shovel. From this machine
evolved the family of construction
machines known as
the crane-shovel
The ______ consists of three
major assemblies:
* carrier or mounting
* a revolving superstructure containg
the power and control unit (a.k.a.
revolving deck or turntable)
* a front-end attachment
crane-shovel
are commonly used for
excavating vertical shafts and
footings, unloading bulk materials
from rail cars and ships, and moving
bulk material from stockpiles to bins,
hoppers, or haul units. Operation
relies on a closing line to control the
bucket halves.
Clamshells
______ is a bucket equipped
constuction equipment used for excavating
and transporting all classes of earth (except
solid rocks without prior loosening) to
nearby trucks or other hauling equipments.
Applications:
* Best suited for embankment digging,
sidecasting, loading haul units, dressing
slopes, loading hoppers, and shallow trench digging.
Power shovel is a bucket equipped
constuction equipment used for excavating
and transporting all classes of earth (except
solid rocks without prior loosening) to
nearby trucks or other hauling equipments.
Applications:
* Best suited for embankment digging,
sidecasting, loading haul units, dressing
slopes, loading hoppers, and shallow trench
digging
______ are primarily used for lifting,
lowering, and transporting loads, moving
them horizontally by swinging or traveling.
______ are rated by a specific capacity
system (PCSA), which defines safe load
capacities based on operating radius. This
ensures cranes operate within safe
parameters during construction.
Cranes
The ______ is a versatile machine with the
longest digging and dumping reach in the
crane-shovel family, capable of excavating
significant depths in soft to medium-hard
materials. However, it lacks the precise
digging control and lateral stability of a
shovel, leading to potential bucket
movement during hard digging and
increased spillage during loading.
dragline
A ______ is a tractor equipped with a front-mounted blade used for earthmoving tasks such as pushing, digging, and leveling
soil.
Operations:
The ______ lowers its blade to cut and gather soil until the blade is full.
It pushes the material to the desired location, where it is unloaded by raising
the blade, pushing it over a cliff, or into a pile.
Both rubber-tired (wheel) and crawler (track) ______ are available, and they can
be equipped with additional attachments like rakes, plows, and rippers.
bulldozer (dozer)
LOADERS
A ______ (front-end ______ or bucket ______) is a tractor equipped with a front-end bucket, used for various earthmoving and material handling tasks.
loader
______ come in two types:
Wheel loaders- offer excellent mobility and
can move between jobs over the road at speeds of 40 km/h or higher, but they are less capable on difficult terrains compared to track loaders.
Track loaders -with low ground pressure and high tractive effort, perform
better in rough or low-trafficability soils but are slower and less productive
over long distances.
Loaders
______ are machines used for excavating,
loading, hauling, and dumping material over medium to long distances. They cut material using replaceable blades and can be either self-loading or require assistance from a pusher tractor.
Advantages:
Efficient for long-distance hauling, with some models capable of self-loading.
Disadvantages:
Most ______ need pusher tractors, except for elevating and auger types.
SCRAPERS
______ and ______ are key for
transporting excavation materials.
Trucks and wagons
______ are flexible and can move quickly
between sites, with models designed for
on- and off-highway use. ______,
equipped with earthmoving semitrailers,
are efficient for spreading material,
especially when moving.
Trucks
Wagons
