Analysis of Project Time Scheduling on Box Culvert at Banjar Sugihan – Kandangan, Surabaya with Pert

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Analysis of Project Time Scheduling on Box Culvert at Banjar Sugihan – Kandangan, Surabaya with Pert

Method

Ganang Ilham Gutomo, Diah Ayu Restuti Wulandari Departement of Civil Engineering, Narotama University Surabaya

[email protected], [email protected]

Abstract

There are many ways to solve problems that always arise from floods, one of which is by making channels and roads using the Box Culvert construction. As construction progresses, there are more and more problems that arise during construction, one of which is project management problems, which before the implementation of construction is always planned to determine the schedule, time, and cost needed. In the construction of the Gunung Sari Box Culvert Diversion project, there was a schedule setback in the planned schedule which should have been implemented for 270 days. The CPM and PERT methods are used to speed up work and delays. The acceleration of the project duration from the critical path for 187 days, the time obtained on the critical path with the addition of labor with normal costs of Rp. 45,222,751,385.35 and after the addition of labor or time acceleration with a total cost of Rp. 45,542,140,274.24. after accelerated.

Keywords:

Box Culvert, Critical Path Method, Duration, PERT

1. Introduction

The project is located in Surabaya City, East Java, along Jalan Banjar Sugihan, Tandes District to Jalan Kandangan, Benowo District, Surabaya City, East Java. The project is intended to reduce the number of vehicles causing congestion from Jalan Kyai Amir who wants to turn towards Jalan Manukan Kulon to Jalan Kandangan and from Jalan Banjar Sugihan which will turn back towards Jalan Kandangan, Benowo District. The area of the Jalan Kecamatan Tandes to Kecamatan Benowo whose geographical location there is a river flow from Jalan Banyu Urip so that the road passed in the area is not wide enough and the traffic flow that passes through it is too dense. So, it is necessary to build a Box Culvert in the area which is useful for reducing the density of traffic fl ows that pass through the road and does not reduce the function of the river flow to accommodate water discharge from settlements around the Benowo District to Tandes District. The Box Culvert project on the road requires a cost of Rp. 75,565,747,573.04, which is the Surabaya City Budget, which has been delayed in the agreed schedule.

. Therefore, there is a need for analysis for scheduling in projects related to the acceleration of project time, there are several methods that can be used, one of which is the Program Evaluation Review Technique (PERT). To analyze the schedule in the implementation of channel and road project development with Box Culvert because this method can control critical activities that occur in the project and further optimize the tim e obtained to complete them.

1.1. Literature Review

The application or application of network planning in project implementation requires requirements that must be met to be implemented. These requirements are certainty about the project that must be impl emented. If there are provisions regarding the project to be implemented, then the next stage is the network planning application stage which consists of three groups, namely: design, design, and design improvement (Frederika, 2010).

Crashing In this event, changing times cause the costs incurred to also change. In the Crashing method, there are several terms related to the time and cost of an activity. These terms include (Dimyati & Nurjaman, 2014)

Critical Path Method (CPM) The CPM method is known for the critical path which has a series of activity components with the longest amount of time and shows the fastest project completion time. So, the critical path consists of a series of critical activities, starting from the first activity to the last project activity. (Soeharto, 1999) PERT, which stands for Program Evaluation Review Technique, is a project management methodology used to schedule, manage and coordinate modules/work sections in a project (Isa, 2014).

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The PERT method is a method that can calculate the duration of project completion that contains uncertainty, namely the duration of the activity. Activity duration is expressed in 3 predictors, namely optimistic time, most likely time, and pessimistic time (Vizkia et al., 2014).

2. Methodology

2.1. Problem Identification

In the planned schedule, which was originally planned at 47.407% but the realization in the field reached 35.845% which had a delay deviation of 11.562%. Infield observations as well as from data sources received delays occur due to various causes of problems from project implementers who have not ordered Box Culverts at the factory, heavy equipment problems that are often constrained, lack of working workers, lack of workers in every worker's job, work the installation of Box Culverts which can only be done at night and the obstruction of soil excavation which makes some work stop. Of the various problems that arise that result in delays in work, the formulation of the problem is determined to speed up the analyzed project time to avoid delays.

2.2. Data collection

In collecting data, primary data and secondary data are taken from within the Box Culvert channel project Primary Data: Research Questionnaire Value Tm, To, Tp

1. Secondary Data: List of Project Budget Draft (RAB) 2. Box Culvert Plan Plan Drawing

3. Schedule the Project

4. Documentation of work drawings in the project 2.3. Data processing

In data processing, the sequence of steps is carried out systematically and logically by the theory of work problems to produce an accurate analysis to achieve this research. The data is taken by a method that can be implemented by researchers, namely the Critical Path Method (CPM) to determine the critical network in project activities and the Program Evaluation Review Technique (PERT) method to determine the acceleration of the project time. The stages in analyzing the data obtained by the author are as follows:

1. Calculating project work duration

2. Determine the three durations of the activity 3. Determine the possibility of project completion 4. Determining the Acceleration of Activity Duration

3. Results and Discussion

3.1. Network Diagram Preparation

Compile a Network or Network Diagram on the preparation of the Gunung Sari Diversion Channel Box Culvert project to get a working relationship between activities using Microsoft Project to arrange work activities for each other.

Figure 1 Network Diagram Preparation

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The following figure is obtained from Microsoft Project which obtains the critical path in the table above which is the path that there can be no time delay in the work or execution

3.2. Activity Duration Calculation

After getting the resulting network then looking for an optimistic duration value, a pessimistic duration value, the most likely duration value. Of the three durations, it was obtained from a questionnaire given to practitioners who were involved in project work and had a better understanding of the timing of making the duration. So that the results obtained from optimistic time duration, pessimistic time duration

Tabel 1 Activity Duration Calculation No Activity Name

Plan Duration (Day)

Average Duration (Day)

Te

(to+4tm+tp)/6 to (optimistic) tm (often) tp (pessimist)

A Soil Excavation with

Heavy Equipment 77 79 88 101.75 88.79

B Land Transport Out of the

Project 70 70.75 77 99.25 79.67

C Gedeg Guling Foundation

Works 63 65.5 74.5 85.75 74.88

D

Rent Steel Sheet Pile (SSP) Height = 6 m + Braching

84 85.5 92 119 95.42

F

Installation of Steel Sheet Pile (SSP) Height = 6 m + Braching (Including Piling and Pulling)

84 84.75 94.75 121.25 97.50

G

Work of Reinforced Concrete Plate Strip fc 30 Mpa Tb. 40 cm (For Ground Floor)

147 150.75 159 179.25 161.00

H

Procurement of Top- Bottom Box Culvert Uk.

350,350,120 fc 35 Manufacturing Type A

168 169.25 178.75 205 181.54

I

Top-Bottom Mount 350,350,120 fc 35 Mpa Type A Manufacturer

140 138.25 152.75 178.75 154.67

J

Procurement of Box Culvert Top-Bottom Uk.

350,350,120 fc 35 Manufacturing Type B

168 171.25 181 205 183.38

K

Top-Bottom Mount 350,350,120 fc 35 Mpa Type B Manufacturer

140 143 157 185.75 159.46

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350,350,120 fc 35 Manufacturing Type C

168 169.25 178.5 204 181.21

M

Top-Bottom Mount 350,350,120 fc 35 Mpa Type C Manufacturer

140 142.25 155 178.75 156.83

N

350,350,120 fc 35 Manufacturing Type D

168 169.25 180.75 205 182.88

O

Top-Bottom Mount 350,350,120 fc 35 Mpa Type D . Manufacturer

140 141.75 156 184.5 158.38

P

350,350,120 fc 35 Manufacturing Type E

168 173 180 210.25 183.88

Q

Top-Bottom Mount 350,350,120 fc 35 Mpa Type E . Manufacturer

140 142.75 151.75 177.75 154.58

R

350,350,120 fc 35 Manufacturing Type F

168 169 176.25 208.5 180.42

S

Top-Bottom Mount 350,350,120 fc 35 Mpa Type F . Manufacturer

140 142 153 180.25 155.71

T

350,350,120 fc 35 Manufacturing Type G

168 168.5 180.75 211.5 183.83

U

Top-Bottom Mount 350,350,120 fc 35 Mpa Type G . Manufacturing

140 144.5 153.75 174.25 155.63

V

350,350,120 fc 35 Manufacturing Type H

168 171.5 183.75 215 186.92

W

Top-Bottom Mount 350,350,120 fc 35 Mpa Type H . Manufacturer

140 141.75 150.5 180 153.96

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350,350,120 fc 35 Manufacturing Type I

168 170.25 178 206 181.38

Y

Top-Bottom Mount 350,350,120 fc 35 Mpa Type I Manufacturer

140 143.75 153.5 174.5 155.38

Z Welding Work Join Iron

Plate 168 170 181.5 216.5 185.42

Te obtained is 186.92 days from activity V which is the longest activity and has a critical path in it that has no time delay in it. It can be said that the longest path of a project rounded off the duration of the known 187 days of that V activity. And the total value of variance (σ2) on the critical path found a value of 5441.35 which is used to find the standard deviation to be able to find the probability value in its implementation.

3.3. Determining the Probability of Project Completion

Meanwhile, to obtain the standard deviation value on the critical path is as follows:

S = √Σ (variance on the critical path) S = √ Σ (variance on the critical path) = √ 5441.35

= 73.77

Adjusting the maximum time for completion on the daily calendar of work agreements, the probability value can be calculated by:

Z = ^{T (d) – Te}

𝑆

Z = ^{T (d) – Te}

𝑆

Z = ^{270 – 187}

73,77

Z = 1.125

Based on these calculations, the z-value is 1.125, so that when viewed in the z-score table, the 1.125 value has a probability value of 0.8686. This value, if presented as a percentage, will be 86.86% or it can be said that the probability of the project being completed in less than 187 days is 86.86% the probability that it will occur.

3.4. Determining the Acceleration of Activity Duration

Crash Duration and Crash Cost calculations are then carried out for all project activities on the critical path so that when recapitulation is carried out, the following values will be obtained:

No Activity Normal Duration

(Day) Normal Cost (Rp) Crash Duration

(Hari) Crash Cost (Rp)

1 A 88.79 1,153,101,865.36 73.99 1,160,501,170.92

2 B 79.67 1,271,599,939.50 66.39 1,278,238,828.39

3 C 74.88 320,673,697.34 62.40 326,913,280.68

4 D 95.42 566,060,000.00 79.51 574,011,388.89

5 E 97.50 532,234,436.80 81.25 540,359,436.80

6 F 161.00 4,939,621,763.79 134.17 4,953,038,430.46

7 G 181.54 2,188,956,000.00 151.28 2,204,084,472.22

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8 H 154.67 36,306,937.04 128.89 49,195,825.93 9 \I 183.38 2,188,956,000.00 152.81 2,204,237,250.00 10 J 159.46 36,306,937.04 132.88 49,595,131.48

11 K 181.21 12,562,704,000.00 151.01 12,577,804,694.44

12 L 156.83 208,370,247.36 130.69 221,439,691.80 13 M 182.88 8,541,687,000.00 152.40 8,556,926,583.33 14 N 158.38 141,675,982.58 131.98 154,873,899.25 15 O 183.88 8,541,687,000.00 153.23 8,557,009,916.67 16 P 154.58 141,675,982.58 128.82 154,557,927.02 17 Q 180.42 214,137,000.00 150.35 229,171,722.22 18 R 155.71 3,551,765.58 129.76 16,527,460.02 19 S 183.83 214,137,000.00 153.19 229,456,444.44 20 T 155.63 3,551,765.58 129.69 16,520,515.58 21 U 186.92 95,172,000.00 155.76 110,748,388.89 22 V 153.96 1,578,562.48 128.30 14,408,423.59 23 W 181.38 962,280,000.00 151.15 977,394,583.33 24 X 155.38 14,207,062.32 129.48 27,154,978.99 25 Y 185.42 342,518,440.00 154.51 357,969,828.89

Total 45,222,751,385.35 Total 45,542,140,274.24

With the addition of 25 workers in the construction of the Gunung Sari Diversion Channel Box Culvert, it can speed up work, especially in the critical path that has no time delay in the work that has been accelerated.

With a project duration of 187 calendar days with a probability of 86.86%, it can be accelerated by add ing handyman workers as calculated above the costs incurred are Rp. 45,542.140.274.24 from the planned costs of Rp. 45,222.751,385.35 and the probability that is found to be 86.86% of the work can be completed.

4. Conclusion

1. From the Critical Path Method, we get a critical path that cannot have a delay in it, including soil excavation activities, soil transportation, installation of bolster layers, strip plate casting, procurement of box culverts, installation of box culverts, and welding of joint plates that is a critical activity

2. By using the PERT method, an acceleration in the implementation of which the duration of the plan for 270 days can be accelerated by using the method by 187 days with the possibility that 86.86% of the work can be completed during that duration.

3. By ensuring that the acceleration is carried out with a time duration of 187 days, activities on the critical path can be added to the addition of handyman labor obtained at a normal cost of Rp. 45,222,751,385.35 while the costs incurred by the project after the addition of a handyman or time acceleration with a total cost of Rp.

IDR 45,542,140,274.24. after accelerating.

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5. Suggestion

From the results of the research carried out, it is hoped that these suggestions can be considered in their implementation

1. To avoid delays in the implementation, more attention is needed, especially in critical activities which are activities that cannot be delayed

2. In planning project scheduling, it is necessary to use the acceleration method to get more effective and efficient scheduling results in work during implementation

3. For further research it is necessary to calculate the inhibiting factors and other accelerations to get a more optimal time in it to reduce the inhibiting factors in its implementation

5.1. Acknowledgements

In completing the preparation of this journal, I would like to express my gratitude to Mrs. Diah Ayu Restuti Wulandari as an Advisory Lecturer who has guided, spent time, and energy, and also provided suggestions, corrections, and directions for the preparation and writing of this journal. And my parents always encourage me, and my brothers appreciate the support that has been given. Friends of Civil Engineering students at Narotama University Surabaya, who both provided support and enthusiasm in this preparation. Thank you to those who have helped complete the selection process.

References

Dimyati, H., & Nurjaman, K. (2014). Manajemen proyek. Pustaka Setia.

https://elibrary.bsi.ac.id/readbook/200052/manajemen-proyek

Frederika, A. (2010). Analysis of Acceleration Construction by Adding Optimum Work Time on the Constructiion Project (Case Study: Super Villa Development Project, Peti Tenget-Badung). Jurnal Ilmiah Teknik Sipil, 14(2), 113–126. https://pdfcookie.com/documents/jurnal-analisis-percepatan-pelaksanaan-dengan- menambah-jam-kerja-optimum-pada-proyek-konstruksi-52e116x0j1v8

Isa, I. (2014). Pentingnya sistem informasi dalam keberhasilan sebuah proyek (1st ed.). Graha Ilmu.

https://inlislite.kalselprov.go.id/opac/detail-opac?id=29923

Soeharto, I. (1999). Manajemen proyek : dari konseptual sampai operasional (2nd ed.). Erlangga.

Vizkia, N. (Naura), Sugiono, S. (Sugiono), & Mada Tantrika, C. F. (2014). Perbandingan Metode Pert Dan Fuzzy Logic Application for Schedulling (Flash) Pada Penjadwalan Proses Fabrikasi Boiler (Studi Kasus: PT Indonesian Marine Corp. Ltd.). Jurnal Rekayasa Dan Manajemen Sistem Industri, 2(3), 129455.

https://doi.org/10.0/CSS/ALL.CSS

Biography / Biographies

Ganang Ilham Gutomo, born in Surabaya on November 6, 1998. is the son of Wulan Dyah Hananing, whose father is Wahono and mother is Sih Murni, father works as a retired soldier, the mother is a housewife. My father was born in Surakarta on June 25, 1963, and my mother is the same as my father's birthplace on April 15, 1964.

And has passed education at the Hang Tuah 9 Surabaya Kindergarten school, Hang Tuah 3 Elementary School Surabaya, SMP Negeri 5 Surabaya, and SMA Negeri 8 Surabaya and studied at Narotama University Surabaya.

When I was in college, I participated in a bridge competition held by another university and won 2nd place. That's what made my experience increase. And when he was in college, he also participated in organizations that were on campus which further added to his experience in organizing.