Optimasi Proyek New Sulphuric Acid Plant Akibat Perubahan Progres Terhadap Alokasi Manpower Dengan Menggunakan Metode Non Linier Programming

Abstract

Construction of New Sulphuric Acid Plant in Gresik in a company engaged in the
textile industry to support the company's expansion process in accordance with the
government's mandate in the textile industry. The construction of this project must be
completed in accordance with the schedule. If this project is delayed, a penalty of 0.1% of
the project value will be imposed. But in fact in the construction process, this project
experienced delays caused by a shift in the allocation of manpower which resulted in
disruption of progress between one work scope and another. The shift was caused by
instructions from the main contractor that were not in accordance with the schedule that had
been made. Therefore, it is necessary to optimize the work so that the project can be
completed according to the completion schedule. In this final project, cost and duration
optimization will be carried out using the Non-Linear Programming (NLP) method. The New
Sulphuric Acid Plant project with WBS which includes Mechanical, Structure, and Piping
work experiences field productivity that is not according to plan, so optimization is carried
out. Furthermore, an analysis is carried out to obtain the optimum project duration at a
minimum cost so that the best option is produced to minimize losses. The results of optimizing
the duration of the 3 work scopes to 269 days in all work scopes from the initial duration of
386 days, 274 days, and 317 days. As for the cost of this optimization, it only saves Rp.
2,300,755 (0.04%) of the actual cost but in this optimization the project does not experience
delays (< 360 days) and will not be subject to fines or penalties. Based on the S curve, 100%
progress on the original plan ended in September 2023, the actual ended in November 2023,
and after the second optimization, 100% progress was achieved at the end of October 2023.