Find out the correlated parameters with construction labor Productivity(CLP)

1. MINISTRY OF EDUCATION,
YOUTHS AND SPORTS
INSTITUTE OF TECHNOLOGY OF CAMBODIA
Department Of Industrial And Mechanical Engineering
FINAL YEAR THESIS
Topic: Investigation on the relation of Heat Stress to
Construction Labor Productivity for Rebar workers
Case Study: Phnom Penh
Student’s Name : KUM Visal & OU Puthy
Advisor : Dr. Kinnaleth VONGCHANH
Co-advisor : Dr. Sarin CHAN
Academic year : 2018-2019

2. I. Introduction
II. Objectives
III. Methodology
IV. Experimental procedure
V. Data analysis
VI. Results and conclusion
Contents Slide: 2

3. I. Introduction
 Increase of the risk of heat
 Exacerbation of heat
 Heat-related illnesses
 High of heat-related accidents
Global warming
Rapid urbanization
(heat island effect)
Increase of the frequency and
duration of extremely high temperatures
Prolonged work
duration
Strenuous physical
activities
Increase of extremely
high temperatures
Slide: 3

4. Find out the correlated parameters with
construction labor Productivity(CLP)
Find out the work productivity of rebar workers
Conduct measurement on Heat stress to
construction site
II. Objective Slide: 4

5. Participants
12 men rebar workers
No major health problems
No drinking Coffee and alcohol
Cardiovascular problem Hypertension Neurological disease Heat related illness
III. Methodology Slide: 5

6.  Measurement devices
Ear Temperature
Heat stress
monitor(WBGT)
Heart rate
polar sensor
Ear Temperature Digital Balance
III. Methodology Slide: 6

7.  Construction labor Productivity (Yi , 2017)
A. Direct/Productive Work Activities
A-1 Make use of wrenches to connect, cut, band, and modify reinforcing steel bars
A-2 Place reinforcing steel bars
A-3 Modify reinforcing steel bars
A-4 Carry reinforcing steel bars
A-5 Use meter sticks for measurements
A-6 Bending
B. Indirect Work Activities
B-1 Walk towards equipment, tools, materials
B-2 Wait for materials to be carried
B-3 Review the list of materials to understand the work
B-4 Talk with foreman and co-workers about the tasks
B-5 Take materials
C. Non-Productive Activities
C-1 Employees or machines, or both, due to work stoppage from any cause
C-2 Chat, smoke, drink, sit, use cell phones, go to the washroom
III. Methodology Slide: 7

8.  Perceptual Strain Index
III. Methodology Slide: 8
(BORG, G. A.V ,1970,) (GAGGE, A. P.,1967)

9. Experiment Procedure
Heat stress monitor
Measurement heart rate Measurement Ear
Temperature
Slide: 9
Demographic information
Medical Checklist
Measurement High Measurement Weight

10. Install Heat Stress Monitor
Demographic and medical Checklist
information
Perceptual Strain Index, productivity
observation, ear temperature were
synchronized measurement every 15min
interval
 Flow of the process
Experiment Procedure Slide:10

11. V. Data analysis Slide: 11

12. VI. RESULT
0:00h
1:00h
2:00h
3:00h
4:00h
5:00h
6:00h
7:00h
DWT IWT NPT
Duration
Activities During Working Time
P1 P2 P3 P4 P5 P6 P7 P8 P9 P10 P11 P12
DWT: Direct Working Time
IWT : Indirect working Time
NPT : Non- productive Time
 Construction Labor Productivity
Slide:12

13. Time
DWT (%)= CLP% IWT (%) NPT (%)
Average Average average
7:00-8:00 55.64% 20.64% 23.72%
8:00-9:00 72.50% 14.17% 13.33%
9:00-10:00 85.42% 7.50% 7.08%
10:00-11:00 68.47% 11.94% 19.58%
1:00-2:00 62.78% 17.92% 19.31%
2:00-3:00 61.67% 18.47% 19.86%
3:00-4:00 68.06% 16.94% 15.00%
4:00-5:00 54.17% 22.64% 23.19%
High
productivity
Less
productivity
 Construction Labor Productivity
Labor Productivity Slide: 13

14. 24.51%
7.19%
10.13%
15.84%
3.61%
4.72%
2.79%
6.94%
0.17%
6.23%
0.23%0.83%
14.65%
0%
5%
10%
15%
20%
25%
30%
A-1 A-2 A-3 A-4 A-5 A-6 B-1 B-2 B-3 B-4 B-5 C-1 C-2
DWT IWT NPT
PERCENTAGE(%)
Total percentage of type working productivity
A-1: Wrenches to connect, Bend, and modify reinforcing steel bars
C-2: Drinking water, chatting, sitting, taking a rest
Labor Productivity Slide: 14

15. Labor Productivity
DWT=67.46% equal about 5h: 24 min per 8 hours
IWT= 16.71% equal about 1h: 20 min per 8 hours
NPT= 15.83% equal about 1h: 16 min per 8 hours
Slide: 15
67.46%
16.71% 15.83%
DWT IWT NPT
Percentage of Productivity

16. 24
26
28
30
32
34
36
7:00
7:15
7:30
7:45
8:00
8:15
8:30
8:45
9:00
9:15
9:30
9:45
10:00
10:15
10:30
10:45
11:00
1:00
1:15
1:30
1:45
2:00
2:15
2:30
2:45
3:00
3:15
3:30
3:45
4:00
4:15
4:30
4:45
5:00
Average WBGT for 15min interval For 6 days
Day 1 Day 2 Day 3 Day 4 Day 5 Day 6
Area Risk II
Area Risk III
Area Risk I
Risk I 26.66 <WBGT< 29.3(˚C)
Risk II 29.4(˚C) ˂ WBGT < 32.1(˚C)
Risk III WBGT >32.1(˚C)
Slide: 16WBGT

17. 35.6
35.8
36
36.2
36.4
36.6
36.8
37
37.2
37.4
7:00
7:15
7:30
7:45
8:00
8:15
8:30
8:45
9:00
9:15
9:30
9:45
10:00
10:15
10:30
10:45
11:00
1:00
1:15
1:30
1:45
2:00
2:15
2:30
2:45
3:00
3:15
3:30
3:45
4:00
4:15
4:30
4:45
5:00
Temperature
Ear Temperature for 15min Interval
Slide: 17Ear temperature

18. Thermal Sensation
6.77%
11.98%
25.52%
46.35%
8.33%
1.04%
0.00%
Neutral and comfortable
Slightly warm
Warm
Hot
Very hot
Extremely hot
Intolerably hot
Thermal sensation (TS) percentage in the morning
10.66%
9.64%
12.69%
18.27%
25.38%
23.35%
0.00%
Neutral and comfortable
Slightly warm
Warm
Hot
Very hot
Extremely hot
Intolerably hot
Thermal Sensation (TS) percentage in the afternoon
Slide: 18

19. Rating of perceived exertion
4.66%
3.11%
8.81%
19.17%
24.35%
20.73%
10.88%
3.63%
2.59%
2.07%
0.00%
Rest
Very, very easy
Easy
Moderate
somewhat hard
Hard
Very Hard
Maximal
Rating of perceived exertion in morning
4.06%
3.55%
20.30%
10.15%
10.15%
9.64%
11.68%
10.66%
12.18%
7.61%
0.00%
Rest
Very, very easy
Easy
Moderate
somewhat hard
Hard
Very Hard
Maximal
Rating of perceived exertion in afternoon
Slide: 19

20. 30%
35%
40%
45%
50%
55%
60%
65%
70%
75%
80%
HRMAX% ( DIRECT WORKING TIME)
p1 p2 p3 p4 p5 p6 p7 p8 p9 p10 p11 p12
Area moderate working load
Area heavy working load
Area Light working load
<=54%(light) 55%-69% Moderate >=70% High
Slide: 20Hrmax%

21. time subject CLP% WBGT TS RPE Ear-T HRmax% Age
7:15 1 0.60 25.08 9.00 4.00 37.00 0.48 23.00
7:30 1 0.67 25.65 9.00 4.00 37.10 0.47 23.00
7:45 1 0.80 26.28 9.00 4.00 37.10 0.54 23.00
8:00 1 0.60 26.65 8.00 4.00 36.70 0.55 23.00
8:15 1 0.93 26.82 10.00 2.00 37.00 0.45 23.00
8:30 1 1.00 28.01 10.00 3.00 37.00 0.51 23.00
8:45 1 0.73 28.14 10.00 5.00 36.90 0.49 23.00
9:00 1 0.73 28.07 10.00 6.00 37.10 0.49 23.00
9:15 1 1.00 27.84 9.00 6.00 37.00 0.49 23.00
9:30 1 1.00 27.33 8.00 5.00 36.70 0.52 23.00
9:45 1 0.67 27.25 8.00 5.00 36.80 0.53 23.00
10:00 1 0.93 27.23 8.00 5.00 36.90 0.48 23.00
10:15 1 0.87 27.44 8.00 4.00 37.20 0.47 23.00
10:30 1 0.67 27.70 9.00 5.00 37.20 0.49 23.00
10:45 1 1.00 30.90 11.00 8.00 36.90 0.68 23.00
11:00 1 1.00 32.34 12.00 8.00 36.80 0.67 23.00
13:00 1 1.00 32.52 12.00 8.00 37.10 0.61 23.00
13:15 1 1.00 31.92 11.00 7.00 36.90 0.60 23.00
13:30 1 0.80 30.58 12.00 8.00 36.80 0.57 23.00
13:45 1 1.00 31.05 12.00 8.00 37.10 0.60 23.00
14:00 1 0.87 31.11 11.00 8.00 37.00 0.54 23.00
14:15 1 1.00 31.98 10.00 8.00 37.10 0.53 23.00
14:30 1 1.00 30.22 9.00 3.00 37.10 0.50 23.00
14:45 1 0.87 29.50 8.00 5.00 37.30 0.56 23.00
15:00 1 0.73 29.16 10.00 3.00 37.30 0.52 23.00
15:15 1 0.20 29.58 10.00 2.00 37.50 0.49 23.00
15:30 1 0.87 29.11 9.00 4.00 37.30 0.53 23.00
15:45 1 1.00 29.19 8.00 8.00 37.30 0.62 23.00
16:00 1 0.80 25.56 7.00 1.00 36.20 0.50 23.00
16:15 1 1.00 26.13 8.00 2.00 36.20 0.49 23.00
16:30 1 0.87 26.54 9.00 3.00 36.00 0.49 23.00
16:45 1 0.80 26.92 9.00 3.00 36.10 0.47 23.00
17:00 1 1.00 26.82 9.00 3.00 36.30 0.42 23.00
Synchronize Data Slide: 21

22. P-value < 0.05
Correlations of Variable with CLP%
Parameter
correlation
coefficient
P-value N comment
TS 0.033 0.542 343 No relationship
RPE 0.142 0.009 343 Very weak Relationship
Ear-T 0.126 0.020 339 Very weak Relationship
Hrmax% 0.123 0.023 343 Very weak Relationship
WBGT 0.024 0.662 343 No relationship
Age 0.173 0.001 339 Very weak Relationship
Correlation Slide: 22

23. Conclusion
 For the construction labor productivity, results
showed that DWT is 67.46%, IWT is 16.71% and
NPT is 15.83%. For the NPT, sitting, chatting and
taking rest are mostly happened.
 We found that correlation of parameter with CLP%
are HRmax%, rating of perceived exertion
,Age(years) and ear temperature. They are
considered as very weak correlation which correlate
coefficient is between 0.0-0.19
Slide: 23

25. Correlations
variable CLP% TS RPE Ear-T HRmax% WBGT Age
Spearman
CLP%
Sig. (2-
tailed)
0.542 0.009 0.020 0.023 0.662 0.001
TS
Sig. (2-
tailed)
0.542 0.000 0.000 0.001 0.000 0.374
RPE
Sig. (2-
tailed)
0.009 0.000 0.000 0.000 0.000 0.002
Ear-T
Sig. (2-
tailed)
0.020 0.000 0.000 0.000 0.000 0.000
Hrmax
%
Sig. (2-
tailed)
0.023 0.001 0.000 0.000 0.000 0.000
WBGT
Sig. (2-
tailed)
0.662 0.000 0.000 0.000 0.000 0.000
Age
Sig. (2-
tailed)
0.001 0.374 0.002 0.000 0.000 0.000

27. Formula Spearman’s correlation

29. Two simple t-test

32. Participants name Age Height Weight
P1: E MI 23 1.55 54.4
P2: CHORK CHINCHAV 25 1.57 55.2
P3: YEOM NUY 45 1.54 48.8
P4: LORY CHORN 32 1.63 63
P5: REN DARA 18 1.6 43.9
P6: HORN SEANGHAI 18 1.7 55.6
P7: Kung VI 28 1.64 69.4
P8: Hor RIN 39 1.7 68.2
P9: Cheom sim 31 1.55 63.4
P10: Aom Phun 37 1.64 60.2
P11: Seom Mo 29 1.72 59
P12: Ring Mang 33 1.7 65.8