Analisis Frekuensi Alami Jembatan Rangka Baja Sei Wampu dengan Matlab dan Abaqus Serta Aplikasinya terhadap Gaya Gempa dengan Modal Analysis

Abstract

Analysis of the magnitude of the earthquake force is important to do because of its large impact on the bridge. The bridge’s natural frequency and the earthquake force have a mutually influencing relationship with each other. Each bridge has a natural frequency value that can be used to calculate the magnitude of the earthquake force that weighs on the bridge. This research is a type of comparative research with a quantitative approach. Comparative research in this study is a comparative study using two main methods. The two main methods used are the Undamped-Degree of Freedom System (Undamped-DOF System) method and the Dunkerley method. In addition, the Modal Analysis method is also used to analyze the magnitude of the earthquake force. The value of the natural frequency and magnitude of the seismic force of the Sei Wampu Bridge based on the analytical method used is 10.97 rad/sec, 784,63 kN and 510,27 kN using the Undamped-DOF System, 10.60 rad/sec, 824,35 kN and 633,62 kN using the Dunkerley method, 8,05 rad/sec, 834,11 kN and 875,46 kN using the Empirical method of SNI 2833:2008, 11.30 rad/sec, 426,21 kN and 426,21 kN using the Analytical method for Simple Continuous Beams, and 10,71 rad/sec, 805,31 kN and 811,31 kN using ABAQUS modeling. Based on the comparison of natural frequency values, Dunkerley''s method is better than other analytical methods. It has the smallest comparison to ABAQUS modeling, so its use is more recommended. In addition, the possibility of resonance at the Sei Wampu Bridge due to an earthquake based on earthquake data that occurred during the last 10 years is very small.