TIME OPTIMIZATION STUDY USING THE CRASHING METHOD ON THE MANGKARAP – GUMPA ROAD IMPROVEMENT PROJECT (DAK)

ABSTRACT

The Mangkarap – Gumpa Road Improvement Project (DAK) initially targeted for completion within 120 calendar days, has experienced delays with a deviation reaching 11.8%. This study aims to accelerate the project's duration using the Crashing method to achieve earlier completion than the initial 120-day timeline.

The research begins with the development of a Work Breakdown Structure (WBS), an analysis of dependency logic, and the creation of a Precedence Diagram Method (PDM). The selected acceleration alternative involves extending working hours with time variations. Acceleration calculations are focused on the critical path to obtain the optimal time and cost.

The project can be completed under normal conditions in 120 days with a cost of IDR 8,382,005,370.91. After implementing crashing by adding one hour of work on the critical path, the duration is reduced to 111 days at a total cost of IDR 8,362,264,025.40. Adding two working hours results in a 105-day duration with a total cost of IDR 8,367,079,713.05. Adding three hours yields a duration of 100 days at a cost of IDR 8,372,014,419.50. The cost differences compared to the normal scenario are IDR 19,741,345.51, IDR 14,925,657.86, and IDR 9,990,951.41 for the one, two, and three-hour additions, respectively. Thus, the most optimal scenario is the one-hour work extension, which meets the target duration with the most efficient cost.

Keywords:Crashing, Precedence Diagram Method, Extended Working Hours, critical path