Analisis Struktur Portal Frame Tahan Gempa dengan Sistem Rangka Momen Biasa (RMB), Rangka Momen Menengah (RMT), dan Rangka Momen Khusus (RMK) Berdasarkan SNI 1726:2019

Abstract

Since the 19th century, portal frames have been used to build industrial buildings because the development process is fast, economical, and efficient. This research aims to look at the cross-section of structural elements in BS 5950-1:2000 spans of 15 m and 40 m using SNI 1726:2019 with modal analysis, including horizontal deflection and stress ratio, using LRFD and ASD methods. The British standard does not consider the presence of seismic loads. Meanwhile, in Indonesia, one of the lateral loads that work is seismic loading. This research was conducted in three seismic zones, including low (OMF), medium (IMF), and high (SMF) earthquakes. The results of this research show that the horizontal deflection's magnitude still falls within the allowable limit, with the maximum value on Tarutung, the SMF system, and KDS E on a 15-m span of 43.828 mm and a 40-m span of 68.703 mm. However, some of the supporting sections for the IMF system and the main structure of the SMF system exceeded the stress ratio capacity. So the structure needs to be evaluated more. After revision, the percentage ratio of the maximum structure's weight using the cross-sections on the Indonesian market covering two methods and three frame systems with spans of 15 m and 40 m are 16.050% and 17.240%, respectively, which are the ASD method and the SMF system. The maximum structure's weight obtained is greater than the cross-sections in the British standard before revision by 13.93% and 13.187%, respectively. Change the maximum horizontal deflection value on Tarutung, the SMF system, for a 15-m span of 31,106 mm and a 40-m span of 41,985 mm. Based on these results, the LRFD method is more economical than the ASD method.