Determination of fundamental vibration period from microtremor and down-0hole methods (case study: Qazvin)
عنوان دوره: هجدهمین کنفرانس ژئوفیزیک ایران
نویسندگان
1دانشگاه علوم و تحقیقات تهران
2دانشگاه پیام نور، پرند، تهران
چکیده
In order to completing geotechnical information and determining of resonance frequency in the Qazvin site, Single station microtremor measurements and downhole methods were carried out. Single station microtremor measurements were done at 5 stations in the Qazvin site. Data were recorded by 2 Hz seismometers and were processed based on the Nakamura (1989) method. The resonance frequency of the ground were determined from the horizontal to vertical (H/V) spectral ratios of microtremors and was developed for the site on the basis of the variation of the resonance frequency. Also, seismic profile testes with depth of 30 m and spacing 1.5 m included shear wave velocity with 3 channel have been done. Ultimately the results of microtremor measurements and down-hole methods were compared. The results indicated that both methods are in agreement with each other with the average value of 3.46 and 4.5 (s) for vibration period.
کلیدواژه ها
 
Title
Determination of fundamental vibration period from microtremor and down-hole methods (case study: Qazvin)
Authors
Mozhdeh Azadi, asghar azadi
Abstract
In order to completing geotechnical information and determining of resonance frequency in the Qazvin site, Single station microtremor measurements and downhole methods were carried out. Single station microtremor measurements were done at 5 stations in the Qazvin site. Data were recorded by 2 Hz seismometers and were processed based on the Nakamura (1989) method. The resonance frequency of the ground were determined from the horizontal to vertical (H/V) spectral ratios of microtremors and was developed for the site on the basis of the variation of the resonance frequency. Also, seismic profile testes with depth of 30 m and spacing 1.5 m included shear wave velocity with 3 channel have been done. Ultimately the results of microtremor measurements and down-hole methods were compared. The results indicated that both methods are in agreement with each other with the average value of 3.46 and 4.5 (s) for vibration period.
Keywords
Nakamura method, resonance frequency, horizental to vertical (H/V), microtermore, down-hole methods