COMPARATIVE ANALYSIS OF ACCELERATION ALTERNATIVES FOR THE DRAINAGE CHANNEL PROJECT ON XYZ STREET USINGTHE TIME-COST TRADE-OFF (TCTO) METHOD

In response to the increasing occurrence of rain, the city government is actively striving to mitigate urban flooding by enhancing the drainage system. Collaboration with contracted construction firms is central to this endeavor, although it is not without its challenges, including community opposition driven by concerns over potential disruptions and limited financial resources among contractors. This study adopts the Critical Path Method (CPM) and Microsoft Project software, supplemented with the Time Cost Trade Off (TCTO) method to expedite project completion, emphasizing a comprehensive evaluation that encompasses both time and financial aspects. Notably, the analysis identifies the most feasible acceleration opportunity within the excavation of ordinary soil for construction, with original plans indicating a cost of Rp. 60,818,919 over a 40-day period. Three alternatives are considered: (1) overtime labor, incurring Rp. 65,520,000, with a 34-day duration; (2) increased workforce, incurring Rp. 68,000,000, with a 34-day duration; and (3) introducing a new addendum for the replacement of manual excavation with heavy machinery, incurring Rp. 37,440,000, with a 16-day duration. In conclusion, this study provides a comprehensive strategy for accelerating the urban drainage project, considering the critical path, time-cost trade-offs, and cost-benefit factors, highlighting the significance of selecting the most cost-effective alternative while addressing community concerns and resource limitations in flood risk mitigation efforts.


INTRODUCTION
In the urban context, weather uncertainty, particularly in the form of frequent rainfall, has emerged as a persistent concern, precipitating significant flood risks.As a proactive measure in the endeavor to mitigate the impact of these floods, the municipal government has taken decisive actions.A central strategy in this endeavor is the establishment of an efficient drainage system, aimed at diminishing the city's vulnerability to flooding.This ambitious project is being executed through a strategic partnership with construction contractors possessing specialized expertise in this field.To ensure the completion of the drainage project prior to the Eid al-Fitr celebration, thereby enabling the city's residents to observe the festival safely and comfortably, stringent measures have been taken.However, regrettably, the project has encountered substantial challenges resulting in detrimental delays.
The timeliness of project delivery has emerged as a pressing issue necessitating resolution.The increasing variance between the actual project schedule and the originally planned timeline has presented substantial impediments impacting various project phases.In addressing these issues, the Time Cost Trade Off (TCTO) methodology has emerged as a pertinent and relevant solution.As articulated by Ervianto (2004), the TCTO concept embodies a systematic and analytical process that prioritizes the evaluation of all activities within a project, with a particular focus on those situated along the critical path.This approach places paramount emphasis on cost considerations in assessing various acceleration alternatives.Moreover, TCTO transcends the temporal dimension, enabling the municipal government to gain comprehensive insights into the financial implications associated with each alternative.
Following meticulous analysis, it becomes evident that expediting the excavation of ordinary soil for construction emerges as the most promising course of action.The initial cost estimate for this task is Rp.60,818,919, with a projected duration of 40 days.However, a comprehensive evaluation of three alternatives has been undertaken.The first alternative involves the incorporation of overtime labor incurring an acceleration cost of Rp. 65,520,000, thereby reducing the duration to 34 days.The second alternative entails augmenting the workforce with an acceleration cost of Rp. 68,000,000, maintaining a 34day duration.The third alternative introduces a new item, which replaces manual soil excavation with the utilization of heavy machinery, incurring an acceleration cost of Rp. 37,440,000, and significantly reducing the timeline to 16 days.
It is imperative to underscore that this evaluation encompasses not only the temporal dimension but also the financial aspects.The results of this analysis underscore the urgency of selecting the most cost-efficient alternative while vigilantly considering community concerns and the inherent resource constraints within the context of urban flood risk mitigation.Thus, the primary aim of this research is to provide a comprehensive perspective on how the Time Cost Trade Off (TCTO) method can be applied to address project delay issues within the vital urban infrastructure construction project, duly considering temporal and financial facets, alongside the community's needs in the realm of flood risk mitigation.

Data Collection Procedure
In this research, data collection was conducted through direct observation using the following references: a. Secondary The data collected consisted of secondary data, specifically the Budget Cost Plan (Rencana Anggaran Biaya -RAB) of the contract.b.Existing time schedules or schedules submitted during the tender process were also collected.c.Data collection was carried out over a period of one month.
This multifaceted data collection approach formed the basis for subsequent analyses, including critical path identification, financial assessments, and evaluation of acceleration measures.

Data Analysis Technique 2.2.1. Identification of the Critical Path
In the drainage project on XYZ Street in Surabaya, each sub-task comprises specific work items.The project's scheduling utilizes a time schedule (S-curve).The project was initially scheduled for completion within 75 calendar days, from January 24, 2023, to April 17, 2023.However, during the execution, the project experienced delays.Specifically, on February 13, 2023, when the project should have already commenced, the progress of the project remained at 0%.
In accordance with the penalty regulations for project delays as stipulated in Article 120 of Presidential Regulation 70 of 2012 regarding penalties for delays, suppliers of goods/services who fail to complete work within the contractual time frame due to their fault are subject to a penalty for each day of delay amounting to 1/1000 (one per thousand) of the contract value or the contract portion value.In this context, if the project is not remedied with acceleration measures, the prescribed penalty will be enforced.

Identification of Project Financing
For the Drainage Channel Construction project on XYZ Street in Surabaya, the contract value is Rp. 2,125,338,733.To perform an analysis of project time acceleration that may impact the project cost, financing details, including direct and indirect costs, will be broken down, as a follow-up to the Time Cost Trade Off (TCTO) method.The following is a breakdown of the work items for the construction of the Drainage Channel on XYZ Street in Surabaya, which will be studied using the TCTO method.These work items will be rescheduled using the Critical Path Method.

Accelerating the Project Completion Time
Accelerating the project's duration leads to changes in both time and cost, which encompass: a. Normal Time is the time required to complete an activity at a normal productivity level.b.Crash Time is the shortest time possible to technically complete an activity.c.Normal Cost represents the direct cost required to complete an activity within the normal time frame.d.Crash Cost is the total direct cost to complete the work within the shortest time frame.
Overtime work productivity is calculated at 75% of normal productivity.Work productivity reflects the relationship between the quantity of work performed and the resources utilized.The following is the weekly progress report data obtained from the Supervisory Consultant.From here is the reference for acceleration.Based on the data from the Supervisory Consultant's weekly progress report, the deviation of the project is -14.16% while the limit is -10.00%,so it is necessary to accelerate so that the project does not experience delays.

Critical Path Method
Based on the data that has been delayed, we reschedule with the remaining time, namely in week 4 on February 14, 2023 until the end of work on April 17.The following are the results of the reschedule with CPM calculations: After getting the reschedule results, we can input it into Ms.Project so that the critical trajectory is known.

List of Critical Activities
Based on the results of Ms. Project analysis for project scheduling, critical activities are obtained.The list of critical activities under normal conditions can be seen in Table 1: The given data pertains to the critical path analysis, where the original duration of a project was 57 days, resulting in a 6-day overtime situation.In light of this, the focus is on identifying alternative acceleration strategies to ensure the project is completed on schedule.
The selection criteria for the critical path activities are as follows: a.The chosen critical activities involve resource work, i.e., tasks that require labor resources and can be expedited through resource optimization.b.These critical activities offer potential for acceleration through either overtime work or increasing the labor force, enabling adjustments to be made to meet the project's deadline.c.Another option is to consider omitting one of the critical activities, provided that its omission does not lead to severe adverse consequences for the overall project.In an academic context, these criteria outline the basis for selecting specific critical path activities for acceleration, highlighting the importance of resource allocation, workforce adjustments, and the potential consequences of omitting certain tasks.

Application of Time Cost Trade Off Method
In the context of planning for overtime work, the standard working hours consist of 8 normal working hours with a 1-hour break (from 08:00 to 17:00).Overtime work is performed beyond the regular working hours (from 19:00 to 22:00).According to the decision of the Minister of Manpower Number KEP.102/MEN/VI/2004, the regulations regarding overtime wages are as follows: https://ojs.transpublika.com/index.php/IJATEIS/E-ISSN: 2828-5425 165 a. Overtime work can only be performed for a maximum of 3 hours in one day and up to 14 hours in one week.b.Employers must provide food and beverages with a minimum of 1,400 calories when overtime work is performed for 3 hours or more.c.For the first hour of overtime work, employees should be paid 1.5 times the hourly wage.d.For each subsequent hour of overtime work, employees should be paid twice the hourly wage.The fundamental principle in determining the items to be expedited is to seek those with the lowest additional costs but the greatest impact.In this context, the selected item for acceleration is ordinary earth excavation.Based on the available data, the volume of this item is 956.24 cubic meters.An analysis of the ordinary earth excavation item is provided in Figure 11

Unit Price Analysis of Ordinary Land Excavation Items for Construction
Here is the translation of the provided calculation: a. Alternative 1 (Overtime Hours Addition) From the critical path analysis, it was determined that there would be overtime for 6 days.In this project, normal working hours are 8 hours, starting from 08:00 to 17:00.Adhering to the requirements of the Minister of Manpower's Decision Number KEP.102/MEN/VI/2004, as specified in articles 3, 7, and 11, which stipulate that overtime work can only be performed for a maximum of 3 hours, the required time is calculated as follows: Given: - Based on the overtime calculation, it requires 16 days of overtime work, which means the cost to be incurred is as follows: -Foreman's Wage = Rp.120,000 x 1.5 = Rp.180,000 Then, the time taken to achieve acceleration is: 40 -6 = 34 days This implies 16 days of overtime and 18 days of normal work.Therefore, the cost of foreman wages for the ordinary earth excavation work item for construction is calculated as: -Overtime Time = Rp.180,000 x 16 x 1 = Rp.2,880,000 -Normal Time = Rp.120,000 x 18 x 1 = Rp.2,160,000 -So, the total cost is Rp.5,040,000.Based on the overtime calculation, it requires 16 days of overtime work, which means the cost to be incurred is as follows: Assistant Mason's Wage = Rp.80,000 x 1.5 = Rp.120,000 Then, the time taken to achieve acceleration is: 40 -6 = 34 days This implies 16 days of overtime and 18 days of normal work.Therefore, the cost of assistant mason wages for the ordinary earth excavation work item for construction is calculated as: -Overtime Time = Rp.120,000 x 16 x 18 = Rp.34,560,000 -Normal Time = Rp.80,000 x 18 x 18 = Rp.25,920,000 So, the total cost is Rp.60,480,000.In conclusion, for the ordinary earth excavation work item in construction, the cost to be incurred is Rp.65,520,000.

b. Alternative 2 (Addition of Manpower)
The addition of manpower is done by recalculating the labor requirements for each activity based on the duration of acceleration or crashing, which will be achieved without increasing the number of working hours per day.From the data in Ms. Project, there is overtime for 6 days.Originally, the work was scheduled from February 14, 2023, to April 3, 2023, but it was extended to April 10, 2023, to meet the rescheduled timeline.This necessitates the addition of manpower.The calculation to determine the required manpower is as follows: We This means the cost of assistant mason wages for the ordinary earth excavation work item for construction is calculated as: -Assistant Mason's Wage = Rp.80,000 x 34 x 22 = Rp.59,840,000 In conclusion, for the ordinary earth excavation work item in construction, the cost to be incurred is Rp.68,000,000.

c. Alternative 3 (New Item Addition)
In this third alternative, the intention is to replace the ordinary earth excavation, which originally involved manual labor, with the introduction of a new item that uses heavy machinery (excavator).To determine the cost associated with this alternative, it is essential to calculate the productivity of the heavy machinery.Here are the specifications of the heavy machinery to be used and its productivity calculation: The productivity calculation for the excavator, based on the type of work being undertaken, is as follows: - From the provided diagram, the total expenditure for the Ordinary Earth Excavation item can be calculated as follows: We This means the cost of assistant mason wages for the ordinary earth excavation work item for construction is calculated as: -Assistant Mason's Wage = Rp.80,000 x 16 x 14 = Rp.17,920,000 As for the Dump Truck calculation, the rental period is already known, and the cost is calculated as follows: We can calculate as follows: So, for the ordinary earth excavation work item in construction, the cost to be incurred is Rp.37,440,000.
For easier comparison, a table is created to summarize the acceleration options.Here is the comparison table:

CONCLUSION
In the analysis of project acceleration through various alternatives, it is evident that each approach comes with distinct cost implications and timeframe reductions.The decision to choose among the alternatives should take into consideration both budget constraints and the urgency of project completion.For future research, a broader range of acceleration methods and the incorporation of real-world site practices and habits should be explored to enrich the analysis and better reflect the complexities of construction project management.
Furthermore, future studies could benefit from the inclusion of additional variables that influence decision-making in project acceleration.This may involve considering factors like resource availability, environmental impact, and potential risks, providing a more holistic perspective for project managers to make informed decisions regarding acceleration strategies.
Source: Processed data (2023) Figure 1.Research Flowchart ojs.transpublika.com/index.php/IJATEIS/E-ISSN: 2828-5425 159 c.Daily productivity after crash = Daily productivity + (3 x hourly productivity x 75%) d.From the daily productivity value after the crash, we can find the project completion time after being accelerated Crash duration = e.Crash Cost and Cost Slope Crash cost is the cost used to carry out project activities within a period of time equal to the duration of the crash.The formula is as follows: Total overtime wage cost = number of workers x total additional overtime time x overtime cost/day f.Crash cost = normal direct cost + total overtime wage cost g.Cost slope is the addition of direct costs per unit time.Basically, it is necessary to find critical activities that will be accelerated which have the smallest cost slope.The formula for calculating the cost slope is found in equation 5 below.  = ℎ  −     − ℎ  Source: Soeharto, 1995 Figure 2. Normal and Shortened Time-Cost Relationship Chart for One Activity 3. RESULTS AND DISCUSSION Based on primary and secondary data obtained from the Drainage Channel Project on XYZ Street, the following information has been gathered: a. Project Owner: A b. Planning Consultant: PT.A c. Supervision Consultant: PT.B d. Executing Contractor: PT.ABC e. Budget Allocation: Rp. 2,500,000,000,f.Contract Value: Rp. 2,125,338,733,g.Execution Period: 72 working days h.Start Date: January 24, 2023 i. Completion Date: April 17, 2023 COMPARATIVE ANALYSIS OF ACCELERATION ALTERNATIVES FOR THE DRAINAGE CHANNEL PROJECT Arif Prasetiyo W., Wateno Oetomo, Esti Wulandari 160 IJATEIS | INTERNATIONAL JOURNAL ON ADVANCED TECHNOLOGY, ENGINEERING, AND INFORMATION SYSTEM https://ojs.transpublika.com/index.php/IJATEIS/E-ISSN: 2828-5425 j.Late Penalty: 0.1% per day k.Deviation Limit: 10.00%The following data pertains to the contract value of the Drainage Channel Project on XYZ Street.Source: Processed data (2023) Figure 3. Recapitulation of Contract Value From the recapitulation value, the RAB data for the Drainage Channel Project on Jl.XYZ can also be drawn.Source: Processed data (2023) Figure 4. RAB (Budget Plan) https://ojs.transpublika.com/index.php/IJATEIS/E-ISSN: 2828-5425 161 In addition to the recapitulation data and rab, the plan timeschedule data is also obtained.Source: Processed data (2023) Figure 5.Time Schedule Plan Source: Processed data (2023) Figure 6.Week-1 Progress Report COMPARATIVE ANALYSIS OF ACCELERATION ALTERNATIVES FOR THE DRAINAGE CHANNEL PROJECT Arif Prasetiyo W., Wateno Oetomo, Esti Wulandari 162 IJATEIS | INTERNATIONAL JOURNAL ON ADVANCED TECHNOLOGY, ENGINEERING, AND INFORMATION SYSTEM https://ojs.transpublika.com/index.php/IJATEIS/E-ISSN: 2828-5425 Source: Processed data (2023) Figure 7. Week-2 Progress Report Source: Processed data (2023) Figure 8. Week-3 Progress Report https://ojs.transpublika.com/index.php/IJATEIS/E-ISSN: 2828-5425 163 Source: Processed data (2023) Figure 9. Acceleration Reschedule Results From the reschedule results, an S-curve comparison of the schedule plan can be drawn, so that it is obtained: Source: Processed data (2023) Figure 10.Comparison of S-Curve of Plan and Reschedule below: Source: Processed data (2023) Figure 11.