ANALISIS POTENSI LIKUIFAKSI MENGGUNAKAN DATA MIKROTREMOR METODE HORIZONTAL TO VERTICAL SPECTRAL RATIO (HVSR) DAN VERTICAL ELECTRICAL SOUNDING (VES) DAERAH BUNGKU PESISIR, MOROWALI, SULAWESI TENGAH

SYUKUR, RISKY MUHAMMAD (2024) ANALISIS POTENSI LIKUIFAKSI MENGGUNAKAN DATA MIKROTREMOR METODE HORIZONTAL TO VERTICAL SPECTRAL RATIO (HVSR) DAN VERTICAL ELECTRICAL SOUNDING (VES) DAERAH BUNGKU PESISIR, MOROWALI, SULAWESI TENGAH. Other thesis, UPN Veteran Yogyajarta.

	Text ABSTRAK_RISKY MUHAMMAD SYUKUR.pdf Download (267kB)
	Text COVER.pdf Download (226kB)
	Text DAFTAR ISI.pdf Download (340kB)
	Text DAFTAR PUSTAKA.pdf Download (235kB)
	Text LEMBAR PENGESAHAN.pdf Download (771kB)
	Text SKRIPSI_RISKY MUHAMMAD SYUKUR.pdf Restricted to Repository staff only Download (16MB)

Abstract

v
ABSTRAK
ANALISIS POTENSI LIKUIFAKSI MENGGUNAKAN DATA
MIKROTREMOR METODE HORIZONTAL TO VERTICAL
SPECTRAL RATIO (HVSR) DAN VERTICAL ELCTRICAL
SOUNDING (VES) DAERAH BUNGKU PESISIR, MOROWALI,
SULAWESI TENGAH
Oleh:
Risky Muhammad Syukur
115.200.043
Bungku Pesisir merupakan salah satu daerah di Kabupaten Morowali yang
terletak di pesisir pantai dengan endapan material sedimen yang tinggi dan
kedalaman muka air yang dangkal sehingga memungkinkan terjadi bencana
likuifaksi. Hal ini didukung dengan letak geologi Bungku Peisir yang berada pada
kompleks tumbukan benua aktif menyebabkan intensitas dari aktivitas gempa
tinggi. Aktivitas gempa dapat digunakan sebagai langkah mitigasi bencana melalui
peta sebaran potensi bencana seperti likuifaksi dengan menggunakan metode
mikrotremor dan VES.
Analisis terhadap data mikrotremor menggunakan metode Horizontal to
Vertical Spectral Ratio (HVSR) mampu menghasilkan parameter frekuensi natural
(f0), ketebalan lapisan sedimen (H), faktor amplifikasi (A0), indeks kerentanan
tanah (Kg), kecepatan gelombang geser (Vs30), serta penggunaan data gempa untuk
menghasilkan peak ground acceleration (PGA) dan ground shear strain (GSS)
yang di dukung dengan data parameter resistivitas dari Vertical Electrical Sounding
(VES). Parameter yang dihasilkan selanjutnya akan dilakukan komparasi untuk
mendapatkan peta potensi likuifaksi yang akurat.
Hasil penelitian dari analisis metode HVSR dan VES menunjukkan sebaran
nilai f0 berkisar 1.57 – 16.05 Hz dengan dominasi f0 sedang menujukan ketebalan
sedimen berkisar 5 – 20 m, ketebalan sedimen berkisar 6 – 56 m dengan ketebalan
sedimen > 30 m tersebar di area dekat pantai, A0 berkisar 1.68 – 10.4 dengan
dominasi rendah, Kg berkisar 0,3 – 23 didominasi dengan kerentanan tanah rendah,
sedangkan persebaran indeks kerentanan tinggi di timur laut dekat pantai lokasi
penelitian, Vs30 berkisar 199.5 – 778.5 m/s dengan klasifikasi oleh tanah keras (SC),
PGA berkisar antara 1.774 – 1.814 Gal, GSS berkisar 0.5 x 10-6 – 4.1 x 10-5 dengan
potensi yang dapat terjadi berupa getaran, retakan, serta penurunan tanah. Hasil
interpretasi VES menunjukkan bahwa daerah penelitiaan tersusun oleh litologi
alluvium, batu serpih sisipan batugamping, batugamping, dan peridotit dengan
keberadaan muka air di kedalaman 3.11 – 14.58 m. Potensi likuifaksi di Bungku
Pesisir dapat terjadi disebabkan litologi penyusun berupa sedimen dengan
ketebalan tinggi serta keberadaan muka air dangkal namun dengan tingkat yang
rendah karena litologi dominan berupa batu gamping yang sukar bercampur dengan
air menjadi cair – kental ketika gempa.
Kata Kunci : Bungku Pesisir, Mikrotremor, HVSR, VES, Likuifaksi
vi
ABSTRACT
LIQUEFACTION POTENTIAL ANALYSIS USING
MICROTREMOR DATA HORIZONTAL TO VERTICAL
SPECTRAL RATIO (HVSR) AND VERTICAL ELECTRICAL
SOUNDING (VES) METHODS IN BUNGKU PESISIR AREA,
MOROWALI, CENTRAL SULAWESI
By:
Risky Muhammad Syukur
115.200.043
Bungku Pesisir is one of the areas in Morowali Regency which is located on
the coast with high deposits of sedimentary material and shallow water level depth
making it possible for liquefaction disasters to occur. This is supported by the
geological location of Bungku Peisir which is in an active continental collision
complex which causes the intensity of earthquake activity to be high. Earthquake
activity can be used as a disaster mitigation measure by mapping the distribution of
potential disasters such as liquefaction using the microtremor and VES methods.
Analysis of microtremor data using the Horizontal to Vertical Spectral Ratio
(HVSR) method is able to calculate natural frequency parameters (f0), sediment
layer thickness (H), amplification factor (A0), soil vulnerability index (Kg), shear
wave velocity (Vs30), and the use of earthquake data to calculate peak ground
acceleration (PGA) and ground shear strain (GSS) which are supported by
resistivity parameter data from Vertical Electrical Sounding (VES). The resulting
parameters will then be compared to obtain an accurate liquefaction potential map.
The research results from the analysis of the HVSR and VES methods show
that the distribution of f0 values ranges from 1.57 – 16.05 Hz with the dominance
of f0 showing a sediment thickness ranging from 5 – 20 m, sediment thickness
ranging from 6 – 56 m with sediment thickness > 30 m distributed in areas near the
coast, A0 ranges from 1.68 – 10.4 with low dominance, Kg ranges from 0.3 – 23
dominated by low soil vulnerability, while the distribution of high vulnerability
index in the northeast near the coast of the research location, Vs30 ranges from 199.5
– 778.5 m/s with classification by hard soil (SC) , PGA ranges from 1,774 – 1,814
Gal, GSS ranges from 0.5 x 10-6 – 4.1 x 10-5 with the potential to occur in the form
of vibrations, cracks and, soil subsidence. The VES interpretation results show that
the research area is composed of alluvium lithology, shale interbedded with
limestone, limestone, and peridotite with the presence of a water table at a depth of
3.11 - 14.58 m. The potential for liquefaction in Bungku Pesisir can occur due to
the constituent lithology of sediment with a high thickness and the presence of a
shallow water level, but with a low level because the dominant lithology is
limestone which is difficult to mix with water and becomes liquid - viscous during
an earthquake.
Keywords : Bungku Pesisir, Microtremor, HVSR, VES, Liquefaction

Item Type:	Thesis (Other)
Uncontrolled Keywords:	Bungku Pesisir, Microtremor, HVSR, VES, Liquefaction
Subjects:	Q Science > QE Geology
Divisions:	Faculty of Engineering, Science and Mathematics > School of Engineering Sciences
Depositing User:	Eko Yuli
Date Deposited:	30 Apr 2024 08:36
Last Modified:	30 Apr 2024 08:36
URI:	http://eprints.upnyk.ac.id/id/eprint/39376

Actions (login required)

View Item