Work Improvement

7/27/2019 Work Improvement

1/14

CE 5806 - Construction Project & Site Control 0

Improvement of work flow for lifting of Insulation Material with Tower Crane

Improvement of work

flow for lifting of

Insulation Material

with Tower Crane

CE5806 Construction Project

& Site Control

Presented By

Allan Tay Eng Mian A010

Diwakar Velu A0104260X

Song Zujiang A0103244X

Suresh Lakshana A0103323B

Thirunavukkarasu Thayathan A010
http://www.google.com.sg/imgres?q=nus+logo&um=1&hl=en&sa=N&biw=1920&bih=999&tbm=isch&tbnid=dRIytVAHmwmNqM:&imgrefurl=http://www.siiaonline.org/?q=events/visions-a-region%E2%80%99s-future-south-asia-2060&docid=fUq8DbIPvmvMIM&imgurl=http://www.siiaonline.org/files/u3709/NUS_LOGO_-_blue.jpg&w=500&h=262&ei=RH-9TqDaH4jZrQfC9628AQ&zoom=1


2/14



CHAPTER 1: INTRODUCTION

1.1 Background Information

The Down Town Line is one of the on-going MRT project that is being constructed in Singapore

Government to ease the traffic congestion. This line is connecting Bukit Panjang to the Expo for

40 kms and is one of the important project in terms of completion and the cost considered .Hence

it is very important that the work is carried out effectively and efficiently.

Figure 1. The Down Tine LIne


3/14



Scope of Work Improvement:

The scope of the work improvement report is to analyse a particular construction activity and

show the result of one of cycle of work. This will discuss the problems that are faced such as idle

labours, resource managing etc.. due to the current condition as seen in the video submitted. This

work improvement is done in the following steps

Activity Considered

Actual Work Analysis

Thinking over an ideal Solution

Resolved Problem Analysis

The recommendation for improving the process of the workflow cycle will be given in this report

with a detailed analysis and study. This is a concept of Lean construction.

2.1 Work Description

The video taken is to monitor a DOWN TOWN LINE MRT Project. This is particularly focussed

on the lifting of Insulation Materials at the Bukit Batok Depot for the covering of the roof in

order to reduce the heat affect. This is being shifted with the help of a Tower Crane and Helpers.

Lean Concept


4/14



Objective:

The objective of the work analysis done for the above mentioned activity is as follows

Reduce idle time of work men

Manage the Tower Crane Effectively

Reduce the manpower if necessary

Activity Considered:

The work to be done in the situation taken is to shift a 200 Rolls of Insulation coils to the roof of

the Bukit Panjang MRT where it is to be spread over. The stock is arrived and has been stored at

the ground level.

As in this case it is planned to be shifted with the help of a tower crane. Two workmen are

bought in along with a supervisor and a signal man .The characters are as shown in the video

below.


5/14



Actual Work Analysis :

Below shows the snapshot of the actual work sequence that is to be carried out and the time at

which the particular activity is done and what is the status of the workmen

Scene 1 :

Scene 2:

This scene shows the helpers

loading the material on the rope

for lifting

TIME NOW : 02:10

This scene shows the materials

fully loaded and lifted

TIME NOW : 03:01


6/14



Scene 3:

Thus from the above analysis it is found that

Manpower gets idle once the load is sent. This is because they do not have an extra

loading SLING/ROPE.

Tower Crane gets idle as material needs to be loaded.

A table showing the cycle time study is given below.

This scene shows the workmen

are idle as the crane being at the

top

TIME NOW : 04:52


7/14



Average Actual Time cycle with 1 hook and 2 helpers

Total Duration 10:20

Nos Shifted 14.00

DescriptionSta

rt

En

d

Du

r

Signal man Lifting Supervisor Helper1 Helper2 Crane

Working Time

Working

contributary Idle Time Working Time Idle Time Working Time Idle Time Working Time Idle Time Working Time Idle Time

Sta

rt

En

d

Du

r

Sta

rt

En

d

Du

r

Sta

rt

En

d

Du

r

Sta

rt

En

d

Du

r

Sta

rt

En

d

Du

r

Sta

rt

En

d

Du

r

Sta

rt

En

d

Du

r

Sta

rt

En

d

Du

r

Sta

rt

En

d

Du

r

Sta

rt

En

d

Du

r

Sta

rt

En

d

Du

r

Arrangement of

lifting Sling

00:

00

00:

21

00:

21

00:

00

00:

21

00:

21

00:

00

00:

21

00:

21

00:

00

00:

21

00:

21

00:

00

00:

00

00:

21

00

21

Loading of

materials on to

Sling

00:

21

02:

10

01:

48

00:

21

02:

10

01:

48

00:

21

01:

41

01:

20

00:

21

01:

41

01:

20

00:

00

02:

13

02:

13

00:

21

02:

10

01

49

hooking back 02:10 03:01 00:51 02:10 03:01 00:51 01:41 02:32 00:51 01:41 02:20 00:39 02:13 02:32 00:20 02:10 03:01 0051

Lifting up of Sling

03:

01

04:

52

01:

51

03:

01

04:

52

01:

51

02:

32

04:

52

01:

51

02:

20

04:

52

02:

04

02:

32

04:

52

01:

51

03:

01

04:

52

01:

51

Unloading

04:

52

09:

29

04:

36

04:

52

09:

29

04:

36

04:

52

09:

29

04:

36

04:

52

09:

29

04:

36

04:

52

09:

29

04:

36

04:

52

09:

29

04

36

lowering of Sling

09:

29

10:

20

00:

52

09:

29

10:

20

00:

52

09:

29

10:

20

00:

52

09:

29

10:

20

00:

52

09:

29

10:

20

00:

52

09:

29

10:

20

00:

52

Total

10:

20

00:

51

03:

04

06:

25

01:

12

08:

39

02:

20

07:

31

02:

13

07:

39

02:

43

07

37


8/14



Based on the work carried out and the above calculations, a detailed pie chart is prepared and

plotted as shown below. This gives a detailed report on percentage of idle time and effective

work done,

Working Time22%

Idle Time

78%

Helper 2

Working Time

Idle Time

Working Time

26%

Idle Time

74%

Crane

Working Time

Idle Time


9/14



IDEAL SOLUTION:

From the problem analyzed and the cycle time considered the following strategy is used

Usage of 3 Nos Sling/Rope instead of One.

Reducing a workmen considering the crane rotation time.

Usage of 3 Slings:

The sequence of work done is as follows

When crane is lowered material are loaded and hooked for lifting with Sling 1.

Meanwhile the workmen start loading in the Sling 2

Now as and when the crane is lowered the Sling 2 is hooked and sent without idling the

crane for loading.

Repeating the same process

Reducing the Manpower:

After implementing this idea it is observed that the helpers remained ideal as the crane rotation

time is found to be more 2mins 24 secs, the loading time with 2 helpers . In order to reduce this

time , we replaced 2 workmen by just one 1 Helper. This reduced the ideal time and managed

the tower crane rotation time.

Working Time

25%

Idle Time

75%

Total

Working Time

Idle Time


10/14



A flowchart showing the above operation is given below:-

Based on this proposal, A cycle time table that is prepared is attached herewith.


11/14



Proposed Time cycle with 3 hooks & 1 helpers

Total Duration 12:34

Increase in

efficiency 60%

Nos Shifted 42.00

DescriptionSta

rtEnd Dur

Signal man Lifting Supervisor Helper1 Crane

Working Time

Working

contributary Idle Time Working Time Idle Time Working Time Idle Time Working Time Idle Time

Sta

rtEnd Dur

Sta

rtEnd Dur Start

En

d

D

ur

Sta

rtEnd Dur

Sta

rtEnd Dur

Sta

rtEnd Dur

Sta

rtEnd Dur Start End Dur

Sta

rtEnd Du

Unlocking of Sling 1

00:

00

00:

21

00:

21

00:

00

00:

21

00:

21

00:

00

00:

21

00:

21

00:

00

00:

24

00:

24

00:

00

00:

21

00

21

hooking & Lifting up of

Sling 2

00:

21

03:

03

02:

42

00:

21

01:

12

00:

51

01:

12

03:

03

01:

51

00:

21

00:

51

00:

30

00:

51

03:

03

02:

12 00:51

03:

03

02:

12

00:

21

00:

51

00

30

unhooking of Sling 2,

hooking & lowering of

Sling 3

03:

03

04:

24

01:

21

03:

03

04:

24

01:

21

04:

03

04:

24

00:

21

03:

03

04:

03

01:

00

04:

24

04:

27

00:

03 03:03

04:

24

01:

21

Loading of materials on

to Sling 1

00:

24

04:

24

04:

00

00:

24

04:

24

04:

00

04:

24

04:

54

00

30


Sling 1

04:

28

07:

10

02:

42

04:

28

05:

19

00:

51

05:

19

07:

10

01:

51

04:

24

04:

54

00:

30

04:

54

07:

10

02:

16 04:54

07:

10

02:

16



Sling 2

07:

10

08:

31

01:

21

07:

10

08:

31

01:

21

08:

10

08:

31

00:

21

07:

10

08:

10

01:

00

08:

27

08:

31

00:

03 07:10

08:

31

01:

21


to Sling 3

04:

27

08:

27

04:

00

04:

27

08:

27

04:

00

08:

31

09:

01

00

30


Sling 3

08:

31

11:

13

02:

42

08:

31

09:

22

00:

51

09:

22

11:

13

01:

51

08:

31

09:

01

00:

30

09:

01

11:

13

02:

12 09:01

11:

13

02:

12



Sling 1

11:

13

12:

34

01:

2111:

13

12:

34

01:

21

12:

13

12:

34

00:

21

11:

13

12:

13

01:

00

12:

31

12:

34

00:

03 11:13

12:

34

01:

21


to Sling 2

08:

31

12:

31

04:

00

08:

31

12:

31

04:

00

Total

02:

33

09:

57

No idle

time

02:

54

09:

40

12:

00

00:

34

10:

43

01

51


12/14



A pie chart showing the effective work time & idle time for the proposed work is given below

Working Time

76%

Idle Time

24%

Total

Working Time

Idle Time


13/14



The Comparison of the actual & proposed work is as shown in the bar chart below.

Thus from the analysis it is seen that

S.No Item Actual Proposed

1 Cycle Time 10 m 20 s 12 m 34 s

2 No of rolls transferred 14 42

3 % of working time 25% 76%

4 % of idle time 75% 24%

5 % of productivity increase 60%

62%

88%

76%

78

%

74%

75%

0%

77%

4% 1

5%

24%3

8%

12% 2

4%

22%

26%

25%

100%

23%

96%

85%

76%

0%

20%

40%

60%

80%

100%

120%

Actual Idle Time

Proposed Idle time

Actual Working Time

Proposed Working time


14/14



CHAPTER 5: CONCLUSION

Thus from the work analysis it is see that the small tool has reduce particular cost and

time in the project.

Hence all small activity also must be studied prior t and a proper o being carried out and

analysis is to be done on order to avoid the above.

REFERENCES

Documents

Work Improvement