Chapter 1 remade luong duc long

1


Review
Last week we studied about several characteristics of
Vietnamese construction industry and
about the
construction process. We have known that there is a tight
relationship between the construction industry and the
national economy. The construction industry is one of the
most important and largest industries. We learnt about types
of contractors and five approaches by which facilities are
constructed.
The next chapter “introduction to earthwork”

2


3


4


5


Earthmoving Materials and Operations
• 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, and so on.

6


7


8


9


Number of factors for selecting equipments
• The most important criterion is the ability of equipment to
perform the required work .
• The principal criterion for selection should be maximizing
the profit or return on the investment produced by the
equipment (usually, when the lowest cost per unit is
achieved).
• Others:
- Possible future use
- Its availability
- The availability of part and service
- The effect of equipment downtime on other construction
equipment and operations
10

Planning and controlling for
equipment usage
• After the equipment has been selected for a
project, a plan (such as assignment for
equipment, schedule of usage, plan for
maintenance, risk plan…) must be developed
to efficiently utilize the equipment.
• The final phase of the process is competent
job management to assure compliance with
the operating plan and to make adjustments
for unexpected conditions.
11


• The basic relationship for estimating of all
earthmoving equipment is:
Production= Volume per cycle * Cycles per hour (*)

12


• The term “volume per cycle”= the average
volume of material moved per equipment cycle.
Thus the nominal capacity of the excavator or
haul unit must be modified by an appropriate fill
factor based on the type of material and
equipment involved.
• The term “cycle per hour” must include any
appropriate efficiency factors, so that it

represents the number of cycles actually
achieved per hour. (see Table 2-1)
13


14


15


16


17


Sorting of soils into groups each of which would show
similar behavior is the objective of soil classification.
Any soil classification system must provide us with
information about the probable engineering behavior
of soil.
- Unified Soil Classification System (USCS)
-American Association of State Highway and Transport
Officials (AASHTO) System
18


19

20


21


22


23


24


25