Optimizing Ground Works and Plaster Works for Construction Project

Running head: ASSESSMENT 5
CPCCBC5003A ASSESSMENT 5
Name
Course
Professor
University
City/state
Date

ASSESSMENT 5 2
CPCCBC5003A Assessment 5
Question 1
The two tasks selected are ground works (bulk excavation to site) and plaster works (cement
render to internal).
i) Ground works
a. Accurate measured quantities
From the preliminary estimate file, the measured quantity for ground works (bulk
excavation) is 4,500m2. This includes the area of soil, rocks or vegetation materials excavated
from the site and carted away or used as backfill. The volume of bulk excavation can be obtained
by multiplying 4,500m2 with the average depth of excavation. The depth of excavation in this
task is 1.2m. Thus the volume of bulk excavation is: 4,500m2 x 1.2m = 5,400m3
b. Appropriate productivity constants
Ground works productivity constant includes productivity constant for excavating the top soil
(over area), backfilling and compacting the area one layer after the other. The productivity
constant in this task includes that for labour for storing, transporting, delivering and disposing
the excavating materials.
Productivity constant for ground work (bulk excavation not exceeding 1.5m) = productivity
constant for excavating over area + backfilling, levelling, trimming and compacting (Mishra,
2018).
= 0.62 (labour for excavating over areas) + 0.25 (labour for backfilling, leveling and compacting)
= 0.87

ASSESSMENT 5 3
The units for productivity constant is labour days per unit. In this case, it means that it will take
0.87 labour days to excavate 1m3.
c. Tradesman hours
As aforementioned, the productivity constant of 0.87 means that it will take 0.87 labour days to
complete 1m3 of bulk excavation.
1m3 = 0.87 labour days
5,400m2 = labour days?
5,4 00 m2 x 0.87 labour days
1 m2 =4,698labour days
It is assumed that a working day has 8 hours. Therefore the tradesman hours in 4,698 labour days
is calculated as follows:
1 labour day = 8 hours
4,698 labour days = hours?
4,698 labour days x 8 hours
1 labour day =37,584 trademan hour s
d. Suitable gang size
The gang size that is suitable for this task is 16. This gang size comprises of one supervisor,
one excavator operator, two loaders, four dumper drivers and 8 unskilled labourers.
e. Time needed to complete the task

ASSESSMENT 5 4
The time needed to complete the bulk excavation work will largely be determined by the
productivity of the two excavator operators. Assuming that the productivity of one excavator is
100m3/hour and that the average operating time of an excavator is 4 hours a day.
From the gang size above, there is one excavator operator. This means that the volume of soil
excavated by one excavator working 4 hours a day is:
1 x 4 hours x 100m3/hour = 400m3
But the total volume of bulk excavation is 5,400m3. Therefore the number of days needed to
excavate 5,400m3 of soil is calculated as follows:
400m3 = 1 day
5,400m3 = days?
5,400 m3 x 1 day
40 0 m3 =13 . 5 days 14 days
In addition to excavation, there are other tasks such as backfilling, levelling, trimming and
compacting, which are estimated to take a total of 4 days. This means that the total time needed
for ground works is:
14 days + 4 days = 18 days.
f. Task review
The predecessor of ground works is preliminaries, which include numerous activities, some
that will be undertaken as the project continues. The sequence of the task is appropriate because
it comes after necessary preceding activities have been completed such as demolition, site
clearing, site fencing, rubbish removal, temporary services installation, construction of