Prioritas Pemilihan Tipe Fondasi Jembatan Gantung Cubancer Menggunakan Metode AHP dan Topsis

Abstract

This study focuses on determining the priority for selecting the foundation type for the Cubancer Suspension Bridge in Pakpak Bharat Regency, North Sumatra, by integrating two multi-criteria decision-making methods: the Analytic Hierarchy Process (AHP) and the Technique for Order of Preference by Similarity to Ideal Solution (TOPSIS). The research background is driven by the need to choose a foundation that is not only technically safe but also cost-efficient, time-effective, and environmentally minimal, especially in a location with limited access such as this bridge project. The three main criteria analyzed encompass aspects of Construction (such as cost, time, and ease of implementation), Post-Construction (such as durability and maintainability), and Environmental Conditions (such as ecological impact and accessibility). Data were obtained through questionnaires distributed to nine project experts and stakeholders, supported by literature studies. The AHP analysis results showed that the Construction criterion dominated with the highest weight (0.504), followed by Environmental Conditions (0.294) and Post-Construction (0.201). Both AHP and TOPSIS methods consistently ranked the Shallow Foundation as the best choice, followed by the Caisson Foundation, Bored Pile, and Pile Foundation. This result was reinforced by a sensitivity analysis showing ranking stability. The superiority of the Shallow Foundation is primarily driven by cost and time efficiency, ease of implementation without reliance on heavy equipment, and its suitability with the shallow hard soil conditions at the site, which have high bearing capacity. This research concludes that the integration of AHP and TOPSIS is effective in providing an objective basis for technical decision-making. Practically, this study provides a guideline for planners and implementers of infrastructure projects in regions with similar characteristics. For future research development, it is recommended to incorporate uncertainty analysis using fuzzy logic and to expand the scope of criteria by adding life cycle assessment aspects and more in-depth construction risk analysis.