EARTHMOVING MATERIALS & OPERATIONS

Lecture 03

ECE 404: Construction Technologies & Processes 1

Lecture 01

ECE 404: Construction Technologies & Processes 1

Sung-Woo MOON, Ph.D, P.E

Nazarbayev University

Department of Civil Engineering

LECTURE 3

EARTHMOVING MATERIALS &

OPERATIONS

September 05 , 2018

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ECE 404: Construction Technologies & Processes 3

PROFESSIONAL ENGINEERING

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ECE 404: Construction Technologies & Processes 4

•Earthmoving is the process of moving soil or rock from

one location to another and processing it so that it meets

construction requirements of location, elevation, density,

moisture content.

•Earthmoving activities

–Excavating / loading / hauling / placing (dumping and spreading)

/ compacting / grading / finishing

•For efficient earthmoving process

–Accurate estimating of work quantities and job conditions

–Proper selection of equipment

–Competent job management

EARTHMOVING PROCESS

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ECE 404: Construction Technologies & Processes 5

EARTHMOVING PROCESS

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ECE 404: Construction Technologies & Processes 6

•Choice of equipment influences on the efficiency &

profitability of the construction operation

•Factors that should be considered in selecting equipment

for a project

–The ability of the equipment to perform the required work

•Maximize the profit produced by the equipment

•Achieve the lowest cost per unit of production

–Possible future use of the equipment

–Availability of parts and service

–Effect of equipment downtime on other construction equipment

and operations

EQUIPMENT SELECTION

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ECE 404: Construction Technologies & Processes 7

•Basic relationship for estimating the production

of all earthmoving equipment

𝐶𝑜𝑠𝑡 𝑝𝑒𝑟 𝑢𝑛𝑖𝑡 𝑜𝑓 𝑝𝑟𝑜𝑑𝑢𝑐𝑡𝑖𝑜𝑛 = 𝐸𝑞𝑢𝑖𝑝𝑚𝑒𝑛𝑡 𝑐𝑜𝑠𝑡 𝑝𝑒𝑟 ℎ𝑜𝑢𝑟

𝐸𝑞𝑢𝑖𝑝𝑚𝑒𝑛𝑡 𝑝𝑟𝑜𝑑𝑢𝑐𝑡𝑖𝑜𝑛 𝑝𝑒𝑟 ℎ𝑜𝑢𝑟

𝑃𝑟𝑜𝑑𝑢𝑐𝑡𝑖𝑜𝑛 = 𝑉𝑜𝑙𝑢𝑚𝑒 𝑝𝑒𝑟 𝑐𝑦𝑐𝑙𝑒 × 𝐶𝑦𝑐𝑙𝑒𝑠 𝑝𝑒𝑟 ℎ𝑜𝑢𝑟

Where,

Vol. per cycle ∶ average vol.of material moved per equipment

Cycles per hour ∶ the number of cycles actually achieved expected per hour

PRODUCTION OF EARTHMOVING

EQUIPMENT

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ECE 404: Construction Technologies & Processes 8

(From TM 5-331B, U.S. Department of the Army)

•Job efficiency factors for earthmoving

operations

PRODUCTION OF EARTHMOVING

EQUIPMENT (Cont’d)

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ECE 404: Construction Technologies & Processes 9

•Trafficability

–Ability of a soil to support the weight of

vehicles under repeated traffic

–Function of soil type and moisture conditions

–Factors impacting soil trafficability

•Soil strength / Slipperiness / Stickiness / Slope /

Stoniness

–Drainage, stabilization of haul routes, or the

use of low-ground pressure construction

equipment may be required when poor

trafficability conditions exist

EARTHMOVING MATERIALS:

GENERAL SOIL CHARACTERISTICS

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ECE 404: Construction Technologies & Processes 10

•Loadability

–Measure of the difficulty in excavating and loading a soil

•E.g. Loose granular soils vs. compacted cohesive soils and rock

•Soil unit weight (lbs/yd3or kg/m3)

–Used as measure of compaction

–Factor in determining the capacity of a haul

–Depend on soil type, moisture content, and degree of

compaction

•Moisture content

𝑀𝑜𝑖𝑠𝑡𝑢𝑟𝑒 𝑐𝑜𝑛𝑡𝑒𝑛𝑡 = 𝑀𝑜𝑖𝑠𝑡 𝑤𝑒𝑖𝑔ℎ𝑡 − 𝑑𝑟𝑦 𝑤𝑒𝑖𝑔ℎ𝑡

𝐷𝑟𝑦 𝑤𝑒𝑖𝑔ℎ𝑡 × 100

EARTHMOVING MATERIALS:

GENERAL SOIL CHARACTERISTICS

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ECE 404: Construction Technologies & Processes 11

•Soil

–Consist of gravel, sand, silt, clay, and organic

materials

2mm

SOIL CLASSIFICATION

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•Soil Classification Systems

–Two principal soil classification systems are used

for design and construction in the United States

•Unified Soil Classification System (USCS)

•AASHTO System (American Association of State

Highway and Transportation Officials)

•In both systems, soil particles 7.6 cm (3 in. ) or larger in

diameter are removed before performing classification

tests.

SOIL CLASSIFICATION

•Step 1. Determine Atterberg Limits

SOIL CLASSIFICATION: USCS

Liquid limit (LL) – Plastic limit (PL)