KAJIAN STRUKTUR ISTANA MAIMUN DALAM MERESPON GAYA GEMPA

Abstract

Kawasan Sumatera Utara terdapat dua lempeng aktif (Eurasia) dan beberapa gunung berapi yang aktif, dan berpotensi menimbulkan gempa yang dapat merusak struktur rumah tinggal. Tingginya aktivitas vulkanik gunung Sinabung beberapa tahun terakhir hingga menimbulkan gempa sangat mempengaruhi kehidupan masyarakat Sumatera Utara. Masyarakat Sumatera Utara memiliki Istana Maimun, sebuah bangunan bersejarah yang didesain tahan terhadap gempa, sebelum adanya aturan dan standarisasi bangunan tahan gempa ada. Penelitian ini dilakukan di Jalan Brigjen Katamso, Kecamatan Medan Maimun, Kota Medan. Struktur dimodelkan menjadi frame dan model 3D. Dilakukan analisis ketidakberaturan struktur dan respon spektra dengan SAP 2000. Istana Maimun teratur secara horizontal tetapi tidak beraturan secara vertikal yaitu ketidakberaturan massa, geometri vertikal, diskontinuitas arah penahan gaya horizontal. Dari hasil analisis SAP 2000, diperoleh reaksi struktur dan batasan yaitu periode struktur 0,335 detik (< 0,4676 detik), gaya geser dasar 1455,476 kN (> 80% Vstatis = 1324,7 kN), , simpangan maksimum sebesar 7,301 mm (< 150 mm). Berdasarkan parameter tersebut, disimpulkan Istana Maimun aman terhadap gempa.

Kata Kunci: Gaya Geser Dasar, Ketidakteraturan, Periode Struktur, Reaksi Struktur, Simpangan

ABSTRACT
In North Sumatra, there are two active plates (Eurasia) and several active volcanoes, which have the potential to cause earthquakes that can damage residential structures. The high volcanic activity of Mount Sinabung in recent years to cause an earthquake has greatly affected the lives of the people of North Sumatra. The people of North Sumatra have the Maimun Palace, a historic building designed to withstand earthquakes, before the rules and standards for earthquake-resistant buildings existed. This research was conducted on Jalan Brigjen Katamso, Medan Maimun District, Medan City. Structures are modeled into frames and 3D model. An analysis of structural irregularities and response spectra with SAP 2000 was performed. Maimun Palace is horizontally regular but vertically irregular, namely mass irregularity, vertical geometry, direction discontinuity in resisting horizontal forces. From the results of the SAP 2000 analysis, the structural reaction and boundary obtained are structure period 0.335 seconds (< 0.4676 seconds), basic shear force 1455,476 kN (> 80% Vstatic = 1324.7 kN), maximum deviation of 7.301 mm ( < 150 mm). Based on these parameters, it is concluded that Maimun Palace is safe against earthquakes.

Keywords: Basic shear force, irregularity, structural periode, structural reaction, deviation