Anjarwani, Aliefia Sesanti (2024) Pengaruh Ketidakpastian Model Kecepatan Gelombang Melalui Pendekatan Spatial Autocorrelation Mikrotremor Dengan Konfigurasi Lingkaran Terhadap Respon Tanah Di ITS Surabaya. Other thesis, Institut Teknologi Sepuluh Nopember.
![[thumbnail of 5001201022_Undergraduate_Thesis.pdf]](http://repository.its.ac.id/style/images/fileicons/text.png) |
Text
5001201022_Undergraduate_Thesis.pdf - Accepted Version Restricted to Repository staff only until 1 April 2026. Download (3MB) | Request a copy |
Abstract
Institut Teknologi Sepuluh Nopember merupakan sebuah lembaga Pendidikan yang berlokasi di Kota Surabaya. Surabaya sebagian besar terdiri dari tanah aluvial yang menyebabkan rentan terhadap bencana alam dan gempa bumi. Oleh karena letak geografis yang rawan terhadap bencana, maka perlu dilakukan penelitian mengenai mitigasi dan analisis respon tanah di wilayah tersebut. Penelitian ini dilakukan untuk mendapatkan kurva dispersi dengan galat dengan metode Spatial Autocorrelation Mikrotremor menggunakan bentuk konfigurasi lingkaran dan mendapatkan ketidakpastian model kecepatan gelombang geser terhadap respon tanah di ITS Surabaya. Metode Spatial Autocorrelation merupakan metode survei microtremor untuk mendapatkan kurva dispersi gelombang Rayleigh yang akan digunakan untuk menentukan cepat rambat gelombang geser. Akuisisi data dilakukan di Taman Alumni ITS dilakukan dengan menggunakan konfigurasi lingkaran dengan lima lintasan. Setiap lintasan menggunakan 6 buah geofon dengan dua variasi geofon yaitu 4,5 dan 10 Hz. Panjang lintasan 25 m dan radius 5 m untuk setiap geofon. Data yang didapatkan di inversi dengan metode Neightbourhood Algorithm (NA). Inversi ini menggunakan parameter model asli berupa ketebalan lapisan dan kecepatan gelombang geser. Hasil pengolahan data didapatkan nilai Vs untuk setiap lapisan. Lapisan 1 memiliki rentan nilai 71-100 m/detik sedangkan lapisan 2 memiliki nilai Vs diantara 177-350 m/detik. Kedalaman yang diperoleh pada lapisan pertama yaitu sekitar 6-10 meter, sedangkan lapisan kedua merupakan halfspace. Model terbaik digunakan untuk menganalisis respons tanah 1D dengan pendekatan linear menggunakan domain frekuensi. Kemudian dilakukan analisis respon tanah dan didapatkan nilai respon tanah tertinggi pada upper model yaitu PGA sebesar 0,34 g, PSA sebesar 1,15 g, FAR sebesar 3,13. Adapun nilai CoV pada upper model dan lower model untuk kecepatan geser layer 1 dan 2 secara berturut-turut adalah 9,74% dan 27,82% dan nilai CoV untuk upper model dan lower model untuk kedalaman adalah sebesar 37,83%. Berdasarkan hasil data yang diperoleh semakin besar perbedaan ketidakpastian model Vs di setiap lapisan maka semakin besar pula nilai respon tanah untuk Peak Ground Acceleration (PGA), Psuedo Spectral Acceleration (PSA), dan Fourier Amplitude Ratio.
=================================================================================================================================
Institut Teknologi Sepuluh Nopember is an educational institution located in the city of Surabaya. Surabaya mostly consists of alluvial soil which makes it vulnerable to natural disasters and earthquakes. Due to the geographical location that is prone to disasters, it is necessary to conduct research on mitigation and analysis of soil response in the region. This research was conducted to obtain a dispersion curve with error with the Spatial Autocorrelation Microtremor method using a circular configuration shape and obtain the uncertainty of the shear wave velocity model of the soil response at ITS Surabaya. The Spatial Autocorrelation method is a microtremor survey method to obtain Rayleigh wave dispersion curves that will be used to determine shear wave propagation speed. Data acquisition was conducted at the ITS Alumni Park using a circular configuration with five passes. Each track used 6 geophones with two geophone variations of 4.5 and 10 Hz. The track length was 25 m and the radius was 5 m for each geophone. The data obtained were inversed with the Neightborhood Algorithm (NA) method. This inversion uses the original model parameters in the form of layer thickness and shear wave velocity. The results of data processing obtained Vs values for each layer. Layer 1 has a vulnerable value of 71-100 m/sec while layer 2 has a Vs value between 177-350 m/sec. The depth obtained in the first layer is about 6-10 meters, while the second layer is halfspace. The best model is used to analyze the 1D soil response with a linear approach using the frequency domain. Then the soil response analysis was carried out and the highest soil response values were obtained in the upper model, namely PGA of 0.34 g, PSA of 1.15 g, FAR of 3.13. The error values in the upper model and lower model for layer 1 and 2 shear velocities are 9.74% and 27.82% respectively and the error value for the upper model and lower model for depth is 37.83%. Based on the results of the data obtained, the greater the difference in the uncertainty of the Vs model in each layer, the greater the soil response values for Peak Ground Acceleration (PGA), Psuedo Spectral Acceleration (PSA), and Fourier Amplitude Ratio.
| Item Type: | Thesis (Other) |
|---|---|
| Uncontrolled Keywords: | analisis respon tanah, Fourier Amplitude Ratio, gelombang Rayleigh, kurva dispersi, dispersion curve, ground response analysis, Rayleigh wave, Peak Ground Acceleration. |
| Subjects: | Q Science > QE Geology > QE538.5 Seismic tomography; Seismic waves. Elastic waves Q Science > QE Geology > QE538.8 Earthquakes. Seismology Q Science > QE Geology > QE601 Geology, Structural |
| Divisions: | Faculty of Science and Data Analytics (SCIENTICS) > Physics > 45201-(S1) Undergraduate Thesis |
| Depositing User: | Aliefia Sesanti Anjarwani |
| Date Deposited: | 19 Feb 2024 04:06 |
| Last Modified: | 19 Feb 2024 04:06 |
| URI: | http://repository.its.ac.id/id/eprint/107482 |
Actions (login required)
 |
View Item |