Analisis Optimalisasi Waktu Dan Biaya Proyek Menggunakan Metode Fast-Track Dengan Pembagian Zona Pada Pembangunan Gedung Grha Madya Adyaksa Kejaksaan Tinggi Jawa Timur

Indonesia's construction sector still faces challenges related to project delays, as seen in the construction of the Grha Madya Adyaksa Building for the East Java High Prosecutor's Office (contract value IDR 48,216,615,000.00, contract duration 120 days). The structural work was delayed, extending the actual duration to 143 days despite crashing efforts. This study analyzes the optimization of project time and cost by applying the fast-track method combined with zonal division of work. Using a quantitative case-study approach with a pretest-posttest design, the actual project condition was compared with three scheduling alternatives simulated in Microsoft Project and Excel: Alternative 1 (changed predecessor relationships between zones), Alternative 2 (optimized work duration), and Alternative 3 (optimized labor allocation). All three alternatives accelerated the project: Alternative 1 to 141 days (1.40%), Alternative 2 to 128 days (10.49%), and Alternative 3 to 115.59 days (19.17%). All alternatives also reduced implementation costs, with Alternative 2 achieving the highest savings of 12.39% (IDR 937,664,208.32). Considering the balance between schedule acceleration, cost efficiency, and manageable labor needs, Alternative 2 was determined to be the most optimal alternative for this project.