Analysis of Working Cost and Time of the Structure on the “X” Showroom Project in Surabaya using the

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Analysis of Working Cost and Time of the Structure on the “X” Showroom Project in Surabaya using the

Concept "Earned Value Analysis"

Satria Waseso Ardiyanto, Fredy Kurniawan Faculty of Engineering, Civil Engineering Study Program

Narotama University Surabaya

satria.waseso26@gmail.com , task.sipilnarotama@gmail.com Abstract

Construction management is the study of practicing the managerial and technological aspects of the construction industry. Construction management has a very crucial function and role. The success or failure of a project depends on the management in managing its various resources. The main objective in this paper is to evaluate the time and cost of implementing the structural work, the 12-storey Attic Showroom building on Jalan Dharmahusada No.152 Surabaya. A project often experiences additional work / construction time. Through evaluation, a company must be able to manage and plan an appropriate time and cost. So that in the implementation of structural work activities can be completed on time and at the right cost, so that all kinds of waste that occur can be minimized and the profits to be achieved can be optimized.

Keywords :

Attic showroom projects, Construction management, Efficiency, Structural work

1. Introduction

1.1. Background

Construction management is one of the important aspects that greatly affects cost and time in implementing a project. One of the aspects reviewed from the construction management study in relation to the acceleration of work implementation is the overtime system (additional work hours), as well as the system of adding manpower. Efficiency measures in a project are capital in work according to a predetermined schedule by determining the right equipment and using costs and time skillfully and efficiently in carrying out the work of a project (Ervianto Wulfram, 2002).

In a structural work must have complex problems. The bigger the structural work, the bigger the problems that arise, if not handled properly and correctly, these problems will result in delays in work, cost overruns, waste of resources, deviation in the quality of results and failure to achieve the desired goals and objectives (Dipohusodo, 2006). This is due to the interdependence of many factors in its implementation.

What is no less important in the implementation of structural work is what is called project management and construction management which is applied to all stages of the project starting from design, planning and design, to implementation.

Controlling this construction project using the Concept of Value Results (Earned Value Analysis), is a method that integrates the relationship between cost and time and provides an overview of the condition of the project's continuity (Dwi Kartikasari, 2014). The advantages of this method areprovides information regarding the position of the project's progress within a certain period of time and can estimate the progress of the project in the next period, namely in terms of costs and time for project completion. This method has also been reviewed and written by many other authors so that it can help the author to understand this method. The advantage of Earned Value compared to S-Curve is Remaining Cost analysis.

Based on this background, the problems to be studied are:

1. How do delays in work and cost overruns for MEPs, structures, and architects affect the project?

2. What factors influence work delays and overruns in the special costs of MEPs, structures, and architects?

3. How do you manage costs and time using the earned value analysis concept?

1.2. Project Definition

A project is a business / activity that is complex, irregular, limited by time, budget, resources and performance specifications designed to meet consumer needs, a project can also be defined as an effort or activity organized to achieve important goals, objectives and expectations. by using the budget and available resources, which must be completed within a certain time.

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+ Usage Time⁵ 1.3. The Concept of Earn Value

The Result Value Concept is the concept of calculating the amount of costs according to the budget according to the work that has been carried out or completed (budgeted cost of work performed). When viewed from the amount of work completed, this means that this concept measures the size of the work unit that has been completed, at a time when assessed based on the amount of budget provided for the work. With this calculation it is known the relationship between what has actually been achieved physically and the amount of the budget that has been issued. The basic concept of value can be used to analyze performance and estimate achievement of goals. For this reason, three indicators are used, namely, ACWP (Actual Cost of Work Performed), BCWP (Budgeted Cost of Work Performed) and BCWS (Budgeted Cost of Work Scheduled).

1. ACWP Is the actual cost of the work that has been carried out. This cost is obtained from accounting or project financial data at the reporting date. So ACWP is the actual amount of expenses or funds used to carry out work during a certain period of time.

2. BCWP BCWP shows the result value from the point of view of the value of the work that has been done completed against the budget that has been provided to carry out the project. If the ACWP figure is compared with the BCWP, it will be seen the comparison between the costs incurred for the work carried out with the costs that should have been incurred for the work.

3. BCWS BCWS is a budget for a work package, but is compiled and linked to an implementation schedule. So here there is a combination of costs, schedules and work scope where each element of the work has been given an allocation of costs and a schedule that can be used as a benchmark in the implementation of work.

By using the three indicators above, various factors that indicate the progress and performance of project implementation can be calculated, such as:

a. Cost variant and schedule variant

b. Monitor variant changes against standard numbers

c. Productivity and performance index d. Estimated cost and time of project completion The formula for finding cost and time variants is as follows:

Variant of cost (CV) = BCWP – ACWP¹ Schedule variant (SV) = BCWP – BCWS²

A negative number on the cost variant indicates that costs are higher than budget, called cost overrun.

The zero number shows the work carried out according to budget costs. Meanwhile, a positive number means that the work is carried out at a cost less than the budget, which is called cost underrun. Likewise with schedules, a negative number means being late, zero means being on time and a positive means being faster than planned.

The formula for finding the productivity and performance index is as follows:

Cost Performance Index (CPI) = BCWP / ACWP³ Schedule Performance Index (SPI) = BCWP / BCWS⁴

An index number less than one indicates that costs are higher than the budget, which is called cost overrun. The number one shows the work carried out according to budget costs. Meanwhile, a number of more than one means that the work is carried out at a cost less than the budget, which is called cost underrun.

Likewise with schedules, numbers less than one means late, one means on time and more than one means sooner than planned.

By calculating the variance and index as above, it will be seen that the project will be late or sooner and the costs that must be incurred will be more or less than budgeted, so the progress of the project for the future needs to be predicted in the way below.

Estimated project completion

Total Lifetime + Usage Time (Estimated Completion Date) ECD = SPI

Percentage of Schedule Delay / Acceleration = 100% - ECD / Planned Schedule × 100%⁶ Estimated at Completion costs

EAC = (Total Cost − BCWP) + ACWP⁷

CPI

Percentage of Cost Addition / Reduction = 100% –EAC / Total Cost × 100%⁸

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2. Research Methodology

Figure 1. Research Methodology 2.1. Place and time of research

PeThis research was carried out in the city of Surabaya, which is one of the cities that is currently developing development, therefore this city is currently doing a lot of construction of multi-storey buildings to meet the development of the business market in Indonesia. This research will be carried out between March 2020 - May 2020 with the object of being one of the X Showroom Construction in Surabaya City.

Start

Done

Primary data : - Shop Drawing - Theory - Literature

Identification of problems

Data collection Study of literature

Data Processing Analysis:

- Calculation of work delays - Calculation of cost overruns - Factors affecting tardiness - Factors affecting cost overruns

Conclusions and recommendations

Secondary Data:

- RAB data "S" curve - Project Schedule Plan - Schedule Realization

Plan

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4 2.2. Data Collection Stage

Primary data : Primary data is data obtained directly from the research location and interviews with the Site Manager or the head of the project. Secondary data: in the form of RAB data, “S” curves, project schedule plans, actualization schedule plans.

3. Result and Discussion

This study examines the implementation of the Showroom Development project. According to this project work contract, the completion time is scheduled for 360 calendar days (1 year). Work Value Rp.

22,765,000,000 (Estimated Cost).

In this showroom development project, performance evaluation data and costs are presented in weekly periods or per seven working days. In order to see fluctuations in the work performance of the entire project, data was taken during two evaluation periods, namely:

Evaluation I on September 22 - 28 2019 (week 31) and Evaluation II on November 17 - 24 2019 (week 40), for budget data obtained from the percentage of work weight that must be achieved during the evaluation multiplied by the project cost budget plan . For expenditure data obtained from project finances at the time of evaluation.

3.1. BCWS Calculation (Budgeted Cost of Work Schedule

Table 1. Budgeted Cost of Work Schedule

No Moon Sunday Period

Weekly Plan Weights

BCWS

Per Week (Rp.) Commutative (Rp.) 1 June 26 01-07 1,97 64.616.000.000 64.616.000.000

27 08-14 2,65 86.920.000.000 151.536.000.000 28 15-21 2,32 76.096.000.000 227.632.000.000 29 22-30 3,69 121.032.000.000 348.664.000.000 2 July 30 01-07 3,34 109.552.000.000 458.216.000.000 31 08-14 3,69 121.032.000.000 579.248.000.000 32 15-21 3,20 104.960.000.000 684.208.000.000 33 22-31 3,55 116.440.000.000 800.648.000.000 3 August 34 01-07 3,19 104.632.000.000 905.280.000.000 35 08-14 3,74 122.672.000.000 1.027.952.000.000 36 15-21 3,49 114.472.000.000 1.142.424.000.000 37 22-31 3,78 123.984.000.000 1.266.408.000.000 4 September 38 01-07 3,63 119.064.000.000 1.385.472.000.000 39 08-14 3,76 123.328.000.000 1.508.800.000.000 40 15-21 3,01 98.728.000.000 1.607.528.000.000 41 22-30 3,05 100.040.000.000 1.707.568.000.000 5 October 42 01-07 2,60 85.280.000.000 1.792.848.000.000 43 08-14 2,27 74.456.000.000 1.867.304.000.000 44 15-21 2,10 68.880.000.000 1.936.184.000.000 45 22-30 2,05 67.240.000.000 2.003.424.000.000 6 November 46 01-07 1,86 61.008.000.000 2.064.432.000.000 47 08-14 1,68 55.104.000.000 2.119.536.000.000 48 15-21 1,54 50.512.000.000 2.170.048.000.000 49 22-30 1,49 48.872.000.000 2.218.920.000.000 7 December 50 01-07 0,82 26.896.000.000 2.245.816.000.000 51 08-14 0,75 24.600.000.000 2.270.416.000.000 52 15-21 0,73 23.944.000.000 2.294.360.000.000 53 22-30 0,71 23.288.000.000 2.317.648.000.000

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3.2. BCWP Calculation (Budgeted Cost of Work Performance)

Table 2. Budgeted Cost of Work Performance

No Moon Sunday Period

Weekly Realization

Weight

BCWP

Per Week (Rp.) Commutative (Rp.)

1 June 26 01-07 1,90 62.320.000.000 62.320.000.000

27 08-14 2,60 85.280.000.000 147.600.000.000

28 15-21 2,30 75.440.000.000 223.040.000.000

29 22-30 3,50 114.800.000.000 337.840.000.000

2 July 30 01-07 3,07 100.696.000.000 438.536.000.000

31 08-14 1,98 64.944.000.000 503.480.000.000

32 15-21 3,00 98.400.000.000 601.880.000.000

33 22-31 2,00 65.600.000.000 667.480.000.000

3 August 34 01-07 1,99 65.272.000.000 732.752.000.000

35 08-14 2,00 65.600.000.000 798.352.000.000

36 15-21 1,99 65.272.000.000 863.624.000.000

37 22-31 2,00 65.600.000.000 929.224.000.000

4 September 38 01-07 2,00 65.600.000.000 994.824.000.000

39 08-14 2,00 65.600.000.000 1.060.424.000.000

40 15-21 2,50 82.000.000.000 1.142.424.000.000

41 22-30 2,00 65.600.000.000 1.208.024.000.000

5 October 42 01-07 1,99 65.272.000.000 1.273.296.000.000

43 08-14 2,00 65.600.000.000 1.338.896.000.000

44 15-21 1,85 60.680.000.000 1.399.576.000.000

45 22-30 1,75 57.400.000.000 1.456.976.000.000

6 November 46 01-07 1,25 41.000.000.000 1.497.976.000.000

47 08-14 1,00 32.800.000.000 1.530.776.000.000

48 15-21 1,10 36.080.000.000 1.566.856.000.000

49 22-30 1,01 33.128.000.000 1.599.984.000.000

7 December 50 01-07 1,05 34.440.000.000 1.634.424.000.000

51 08-14 1,01 33.128.000.000 1.667.552.000.000

52 15-21 1,33 43.624.000.000 1.711.176.000.000

53 22-30 1,44 47.232.000.000 1.758.408.000.000

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3.3. ACWP calculation (Actual Cost for Work Performed)

Table 3. Actual Cost for Work Performed

No Moon Sunday Period ACWP

Per Week (Rp.) Commutative (Rp.)

1 June 26 01-07 49.250.000.000 49.250.000.000

27 08-14 66.250.000.000 115.500.000.000

28 15-21 58.000.000.000 173.500.000.000

29 22-30 92.250.000.000 265.750.000.000

2 July 30 01-07 83.500.000.000 349.250.000.000

31 08-14 92.250.000.000 441.500.000.000

32 15-21 80.000.000.000 521.500.000.000

33 22-31 88.750.000.000 610.250.000.000

3 August 34 01-07 79.750.000.000 690.000.000.000

35 08-14 93.500.000.000 783.500.000.000

36 15-21 87.250.000.000 870.750.000.000

37 22-31 94.500.000.000 965.250.000.000

4 September 38 01-07 90.750.000.000 1.056.000.000.000

39 08-14 94.000.000.000 1.150.000.000.000

40 15-21 75.250.000.000 1.225.250.000.000

41 22-30 76.250.000.000 1.301.500.000.000

5 October 42 01-07 65.000.000.000 1.366.500.000.000

43 08-14 56.750.000.000 1.423.250.000.000

44 15-21 52.500.000.000 1.475.750.000.000

45 22-30 51.250.000.000 1.527.000.000.000

6 November 46 01-07 46.500.000.000 1.573.500.000.000

47 08-14 42.000.000.000 1.615.500.000.000

48 15-21 38.500.000.000 1.654.000.000.000

49 22-30 37.250.000.000 1.691.250.000.000

7 December 50 01-07 20.500.000.000 1.711.750.000.000

51 08-14 18.750.000.000 1.730.500.000.000

52 15-21 18.250.000.000 1.748.750.000.000

53 22-30 17.750.000.000 1.766.500.000.000

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3.4. Performance calculations using the method Earn Value Analysis Table 4. Structure Work Performance Status on Week 41

Earn Value Method Calculation The Calculation

Results Information Earn Value Graph I. Cost Parameters

1

CV (Cost Variance) / Cost

variance

BCWP - ACWP

= 2,678,000,000 - 114,330,000 2,563,670,000

CV> 0, Cost Underrun

2

CPI (Cost Performed Index) Cost Performance

Index

BCWP / ACWP

= 2,678,000,000 / 114,330,000

23,42342342

CPI> 1, Cost Underun

II. Time Parameters

1

SV (Schedule Variance)

/Variant integrated

schedule

BCWP – BCWS

= 2,678,000,000 - 4,493,125,000

-1,815,125,000 ^{SV <0,} Schedule

Overrun

2

SPI (Schedule Performaned

Index)

BCWP / BCWS

= 2,678,000,000 / 4,493,125,000

0.5960217

SPI <1, Schedulle

Overrun

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-2,406,625,000

0.657493062 Table 5.Structure and Architect Work Performance Status on Week 49

Earn Value Method Calculation The calculation results Information Earn Value Graph I. Cost Parameters

1

CV (Cost Variance) /

Cost variance BCWP - ACWP

=4,619,875,000 - 181,040,000

4,438,835,000

CV> 0, Cost Underrun

2

CPI (Cost Performed Index) Cost Performance Index

BCWP / ACWP

=4,619,875,000 / 181,040,000

25.51853182

CPI> 1, Cost Underrun II. Time Parameters

1 SV (Schedule Variance) / Variant integrated schedule

BCWP – BCWS

=4,619,875,000 - 7,026,500,000

SV <0, Schedule Overrun 2 SPI (Schedule

Performaned Index)

BCWP / BCWS

=4,619,875,000 / 7,026,500,000

SPI <1, Schedulle

Overrun

Table 6. Estimated costs and time required to complete structural work

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9 Earn Value

Method

Calculation The

calculati on results

Information Earn Value Graph

I. Estimated Costs and Time of Week 41

1

EAC (Estimate at Complectio n) Estimated

Cost of Project Completion

EAC = (Total Cost – BCWP) + ACWP CPI

EAC = 32,800,000,000-2,678,000,000 + 114,330,000 23,423,423,42

1,400,30 7,692

Estimated Cost Greater

Than Project Budget Plan, Rp.

31,399,692, 308

2 ECD (Estimate Complectio n Date) Estimated Time of Project Completion

ECD = Total Lifetime + Usage Time + Usage Time SPI

ECD = 53 – 41 + 41 0.5960217

61.1 Week

≈ 428 Days

Estimated Time Is

Longer Than Project Design Time, 57

Days II. Estimated Cost and Time of Week 49

1

EAC (Estimate at Complectio n) Estimated

Cost of Project Completion

EAC = (Total Cost – BCWP) + ACWP CPI

EAC = 32,800,000,000-4,619,875,000 + 181,040,000 23,423,423,42

1,285,34 0,404

Estimated Cost Greater

Than Project Budget Plan, Rp.

31,514,659, 596

2

ECD (Estimate Complectio n Date) Estimated

Time of Project Completion

ECD = Total Lifetime + Usage Time + Usage Time SPI

ECD = 53 – 49 + 49 0.657493062

55.1Sun day

≈ 385 Days

Estimated Time Is

Longer Than Project Design Time, 14

Days 3.5. Estimated Costs and Time to Complete the Work Structure

Based on the values of BCWS, BCWP and ACWP during the 41st and 49th week reporting as well as the previously obtained CPI and SPI indicators, it can be predicted that the costs incurred are less and the time required to complete all work is longer, which can be seen in Table 16.

If the performance when reporting remains the same until the rest of the work is completed, the predicted costs incurred to complete all structural and architectural work (EAC) will be IDR 31,399,692,308 in the 41st week baseline monitoring and IDR. 31,514,659,596 in the 49th week, then this contractor will experience a profit of Rp. 985,340,404 (under budget / cost underrun).

Meanwhile, the estimated completion time from the schedule aspect is estimated that the work completion time (ECD) is 428 days in the 41st week and 385 days in the 49th week. This means that the project is delayed from the planned schedule of 360 days.

When viewed from the time schedule from the start of the project work, this project has experienced delays due to the problematic construction permit that takes time out and it greatly interferes with other work so that other jobs are forced to experience delays from the predetermined time, another problem of delays is the delay in funds from the owner so that the contractor cannot provide materials on time and slightly reduce these materials.

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10 3.6. Evaluation Process

Based on the results of the analysis, it can be seen that the expenses incurred are below the contract price (cost underrun) but the time required is delayed, therefore the acceleration is rare, namely by ordering materials well in advance to arrive on time. so that there are no more delays and workers can work optimally. Then by adding 2 to 3 more people to meet the weekly progress so that there are no more delays.

Based on the daily reports of labor used quite a lot. So that it can speed up the process of implementing project completion. However, in terms of costs, there will be an over budget for the payment of labor wages. For this reason, the use of labor must be considered and adjusted to the needs of the job.

If it is not considered carefully, until the end of the implementation of this Showroom development project, it will be over budget. For this reason, the use of materials and labor is carried out as efficiently and effectively as possible so as not to experience excess materials and labor, and in purchasing materials, it must also be considered because it could be that the price is too high at the time of purchase. At the time of ordering the material there delay constraints that affect the performance of the project completion.

4. Conclussion

Based on the analysis that has been done, several conclusions can be drawn as follows:

1. Late work and cost overruns have greatly affected progress so that there is no progress report to the Constitutional Court. So that the Owner is reluctant to pay expenses that are not necessarily progress from the work.

2. Factors that influence work bridging are materials that do not come, workers (craftsmen) who are in short supply, lack of coordination between workers in the field and those in the office. Meanwhile, the factors that influence cost overruns are the exhaustion of a lot of materials due to the supervisor's negligence in arranging the materials so that workers (builders) use excessively, additional workers (builders) are done to catch up with progress.

3. The result value (Earned Value) in this evaluation is the estimated time for completion of structural and architect work is longer than the time for structural and architect work plans (schedule overrun) and the estimated cost of structural and architect work is greater than the work budget plan (cost overrun). In the implementation of the Showroom X development project in Surabaya, the Time and Cost Management System has not been carefully planned and made by the company so that it experiences cost and time swelling so that it will experience enormous losses, so if it is not handled quickly by experts, the swelling will be bigger. again and the Contracting company will be penalized. This can be seen from the results of observations and interviews with the Head of the Section.

References

Dipohusodo, I. (2006). Manajemen Proyek Dan Konstruksi. Kanisius.

Dwi Kartikasari. (2014). Pengendalian Biaya Dan Waktu Dengan Metode Earned Value. Teknik Sipil, 7.

Ervianto Wulfram. (2002). Manajemen Proyek Konstruksi.