Development of two components acceleration time histories for Semarang, Indonesia, due to Semarang fault earthquake scenarios using 30 meters soil deposit model

Development of surface acceleration time histories is important for dynamic analysis of structure design and evaluation. Acceleration time histories usually developed from seismograph records due to specific earthquake event. Following the research conducted by Team for Revision of Seismic Hazard Maps of Indonesia 2010 and 2016, Lasem fault and Semarang fault are two closest and dangerous shallow crustal fault earthquake sources which must be taken into account for seismic mitigation of Semarang. This paper presents the development two components surface acceleration time histories for Semarang caused by Semarang fault earthquake scenarios, with magnitude from 6 Mw to 7 Mw and maximum epicentre distance 15 Km. This research was performed by conducting deterministic hazard analysis, response spectral matching and site response analysis to obtain a pair of modified acceleration time histories. Site response analysis was performed by conducting 30 meters soil deposit model by taking the assumption that the position of bedrock elevation is 30 meters below the surface layer. Modified acceleration time histories were developed from a pair time histories (North-South/NS and East-West/EW direction) collected from worldwide historical earthquakes. Modified time histories were developed due to limited time histories data caused by Semarang fault earthquake source.

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Development of seismic risk microzonation map for Semarang due to Semarang fault earthquake scenarios with maximum magnitude 6.9 Mw

MATEC Web of Conferences ◽

10.1051/matecconf/201815901011 ◽

2018 ◽

Vol 159 ◽

pp. 01011

Author(s):

Windu Partono ◽

Masyhur Irsyam ◽

Sri Prabandiyani Retno Wardani

Keyword(s):

Seismic Risk ◽

Site Response ◽

Seismic Microzonation ◽

Site Response Analysis ◽

Response Analysis ◽

Spectral Matching ◽

Acceleration Time ◽

Earthquake Scenarios ◽

Acceleration Time Histories ◽

Time Histories

Research on seismic microzonation of Semarang is still ongoing. The first seismic microzonation research for this area was performed on 2015. Seismic microzonation map was developed by implementing deterministic 1-D site response analysis at 190 boring locations. Lasem fault was considered to be the main earthquake source which taken into account for seismic microzonation research of Semarang. The second research for developing seismic microzonation map was performed on 2016. Following the research conducted by Team for Updating Seismic Hazard Maps of Indonesia 2016, Rawapening Fault, Ungaran Fault, Weleri Fault, Demak Fault and Semarang Fault are five new shallow crustal fault earthquake sources identified in this research. This paper presents the development of seismic risk microzonation map caused by Semarang fault earthquake scenarios with maximum 6.9 Mw. Deterministic 1-D site response analysis was performed at 288 boring locations for developing seismic risk microzonation map. This research was performed by implementing response spectral matching and site propagation analysis. Due to inadequate data caused by Semarang fault earthquake, response spectral matching was implemented in this research to obtain modified acceleration time histories. All acceleration time histories were developed from five different earthquakes with magnitude 6.05 – 6.9 Mw and maximum epicentre distance 15 Km.

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SEISMIC MICROZONATION OF SEMARANG, INDONESIA BASED ON SITE RESPONSE ANALYSIS USING 30 M SOIL DEPOSIT MODEL

Jurnal Teknologi ◽

10.11113/jt.v78.9607 ◽

2016 ◽

Vol 78 (8-5) ◽

Cited By ~ 4

Author(s):

Windu Partono ◽

Sri Prabandiyani Retno Wardani ◽

Masyhur Irsyam ◽

Syamsul Maarif

Keyword(s):

Amplification Factor ◽

Site Response ◽

Ground Surface ◽

Seismic Microzonation ◽

Site Response Analysis ◽

Response Analysis ◽

Acceleration Time Histories ◽

Single Station ◽

Time Histories ◽

Deposit Model

Seismic microzonation study of Semarang is still on-going following the recommendations from the Team for Revision of Seismic Hazard Maps of Indonesia 2010 (TRSHMI-2010). The study was performed by carrying one-dimensional site response analysis at 190 locations and implementing Lasem fault as a closest seimic source that significantly influence the hazard of the city. The analysis was performed using two soil deposit models, 30 m and real soil deposit models, to get ground surface peak acceleration (PGA) and amplification factor of PGA. The results obtained using the first model are then compared with the results obtained using the second model. To perform the analysis bedrock elevation and acceleration time histories data are needed. The bedrock elevation was estimated based on 218 single station seismometer measurements. Five different time histories representing different earthquakes with magnitude 6.5 MW and maximum distance 20 km are collected from worldwide historical earthquake records. The results of this study includes the distribution of surface PGA and amplification factor of PGA. The PGA and amplification factor calculated using 30 meter soil deposit model are greater than the same values calculated using real soil deposit model.

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Stability evaluation of Sermo dam, Yogyakarta, using two components acceleration time histories causes by Java subduction earthquake scenarios

MATEC Web of Conferences ◽

10.1051/matecconf/201819503020 ◽

2018 ◽

Vol 195 ◽

pp. 03020

Author(s):

Windu Partono ◽

Undayani Cita Sari

Keyword(s):

Seismic Sources ◽

Seismic Load ◽

Seismic Loads ◽

Maximum Magnitude ◽

Ground Acceleration ◽

Acceleration Time ◽

Earthquake Scenarios ◽

Acceleration Time Histories ◽

Time Histories ◽

East West

Dam assessment under a specific earthquake event is one of the most important approaches to dam evaluation. The assessments are usually performed by running two different models of seismic loads: spectral acceleration and acceleration time histories. The first model is implemented using seismic load information developed from a national code. The second approach is implemented using earthquake scenarios by conducting acceleration time histories. The National Center for Earthquake Studies 2017 suggested that a shallow crustal fault and subduction are the two most dangerous seismic sources of Yogyakarta Province. This paper presents an evaluation of Sermo dam in terms of dam displacement and peak ground acceleration (PGA) under the Java subduction source earthquake scenarios. The evaluation was performed by conducting twocomponent (north-south and east-west directions) acceleration time histories from Java subduction seismic sources. Due to incomplete data, all acceleration time histories used in this study were collected and modified from worldwide earthquake data bases. Based on the average displacement and PGA values it can be predicted that Sermo dam is strong enough to resist an earthquake with a maximum magnitude of 8.4 Mw and minimum epicentre distance of approximately 160 Km caused by the Java subduction source.

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Building evaluation using two components of acceleration time histories causes by shallow crustal fault earthquakes with maximum magnitude 7 Mw

MATEC Web of Conferences ◽

10.1051/matecconf/201819502011 ◽

2018 ◽

Vol 195 ◽

pp. 02011

Author(s):

Windu Partono ◽

Masyhur Irsyam ◽

Indrastono Dwi Atmanto ◽

Andi Retno Ari Setiaji ◽

Sigit Purnomo ◽

...

Keyword(s):

Ground Surface ◽

Structural Deformation ◽

Maximum Magnitude ◽

Spectral Acceleration ◽

Acceleration Time ◽

Earthquake Scenarios ◽

Acceleration Time Histories ◽

Propagation Analysis ◽

Time Histories ◽

Analysis Stability

Spectral acceleration and acceleration time histories are the two seismic loads generally used for dynamic analysis of a building. The structural design of buildings is implemented using spectral acceleration at the ground surface obtained from the national seismic code. However, acceleration time histories are developed from specific earthquake events and implemented for building evaluation. This paper presents building evaluations of three existing buildings located in Semarang with heights of at least 40 m. The buildings were built on three different soil types, that is, hard, medium and soft soils. The evaluation was performed by conducting two component north-south and east-west directions of acceleration time histories modified from Semarang fault earthquake scenarios having a magnitude of 7 Mw and maximum epicentre distance 15 Km. Due to incomplete data on Semarang fault earthquakes, the acceleration time histories incorporated herein were collected from worldwide earthquake data bases and modified using response spectral matching and seismic propagation analysis. Stability analyses in terms of structural deformation and drift ratio were carried out for the three buildings. The results show that all three buildings have the capability to resists earthquakes up to a maximum magnitude of 6.5 Mw with an epicentre distance of over 5 Km.

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Structural analysis using three-component acceleration time histories caused by shallow crustal fault earthquakes with a maximum magnitude of 7 Mw

MATEC Web of Conferences ◽

10.1051/matecconf/201925805029 ◽

2019 ◽

Vol 258 ◽

pp. 05029

Author(s):

Windu Partono ◽

Yulita Ami Priastiwi ◽

Nuroji ◽

Indrastono Dwi Atmanto ◽

Bambang Pardoyo ◽

...

Keyword(s):

Building Design ◽

Seismic Load ◽

Maximum Magnitude ◽

Acceleration Time ◽

Earthquake Scenarios ◽

Slip Mechanism ◽

Earthquake Sources ◽

Acceleration Time Histories ◽

Time Histories ◽

Hospital Building

Research on the improvement of Indonesian seismic hazard maps has already been carried out by the National Center for Earthquake Studies in 2017. One important global data obtained from this research related with all earthquake sources mechanism which might be used for building design and evaluation. Based on this research there are two important and closest earthquake sources to Semarang, Lasem fault (strike slip mechanism) and Semarang fault (reverse mechanism). This paper presents the dynamic structural evaluations of the hospital building (approximately 49 meters height) located in Semarang, Indonesia, by conducting two seismic load functions, two-component surface spectral acceleration (X and Y directions) developed from Indonesian Seismic Code SNI:1726-2012 and three-component (North-South, East-West and Vertical) of surface acceleration time histories. All acceleration time histories were modified from three earthquake events which represents Semarang fault earthquake scenarios and developed from earthquake events with magnitude from 6.3 to 6.9 Mw and the maximum distance of building to earthquake epicentre 15 Km. Based on the floor deformation and the drift ratio results calculated using dynamic analysis, the building is predicted has the capability on resisting earthquake scenarios up to a maximum magnitude 7 Mw with minimum epicentre distance 10 Km.

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Site response analysis for estimating seismic site amplification in the case of Banda Aceh - Indonesia

MATEC Web of Conferences ◽

10.1051/matecconf/201819710002 ◽

2018 ◽

Vol 197 ◽

pp. 10002

Author(s):

Halida Yunita ◽

Bambang Setiawan ◽

Taufiq Saidi ◽

Nora Abdullah

Keyword(s):

Site Response ◽

Ground Motions ◽

Soil Column ◽

Site Amplification ◽

Site Response Analysis ◽

Response Analysis ◽

Surface Models ◽

Time Histories ◽

The City ◽

Banda Aceh

The city of Banda Aceh is potentially exposed to a significant seismic hazard of seismic site amplification. Estimation of seismic site amplification of the city is urgently required for any mitigation efforts as the city is founded on a thick, soft layer. This study aims to estimate seismic site amplification of Banda Aceh's soil. Analytical models have demonstrated that they can simulate reasonably well the seismic ground motions amplification. The most widely used model is the equivalent linear approach. The approach computes the ground response of horizontally layered soil deposits subjected to transient and vertically propagating shear waves through a one-dimensional soil column. As aforementioned, this study focuses on Banda Aceh-Indonesia which is founded on thick alluvium. Three actual historical time histories and three developed sub-surface models were used to estimate the seismic site amplification of Banda Aceh's soft soil. The used time histories are of 2012 M8.1 Simeulue earthquake, 2013 M6.0 Mane-Geumpang earthquake and 2013 M6.2 Bener Meriah earthquake. Three sub-surface models of three separate sites across the city of Banda Aceh were developed. The site response analysis results reveal the ground motions amplification of Banda Aceh's soils of up to 4.3. Thus, applying the seismic site amplification for structural design at Banda Aceh can be further works.

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Influence of thick soft superficial layers of seabed on ground motion and its treatment suggestions for site response analysis

Open Geosciences ◽

10.1515/geo-2020-0302 ◽

2021 ◽

Vol 13 (1) ◽

pp. 1273-1289

Author(s):

Qifeng Jiang ◽

Mianshui Rong ◽

Wei Wei ◽

Bin Zhang ◽

Jixin Wang

Keyword(s):

Ground Motion ◽

Site Response ◽

Response Spectra ◽

Activity Level ◽

Site Response Analysis ◽

Response Analysis ◽

Physical Parameters ◽

Layer By Layer ◽

Ocean Engineering ◽

Acceleration Time Histories

Abstract The thick soft superficial layers of the seabed greatly influence ground motion generally. It is worth studying how to find out the influence of these soft layers on ground motion parameters and determine reasonable seismic fortification parameters for ocean engineering. Numerical experiments of site response analysis are designed using two offshore engineering sites in this study. First, the borehole profiles are selected and stripped layer by layer to generate new profiles. Second, 108 acceleration time histories are synthesized which basically represent the diversity of input motions’ amplitude and frequency. Third, a method that can automatically calculate characteristic periods and normalize response spectra is created to improve calculation efficiency. Fourth, peak accelerations, response spectra, and characteristic periods at different depths of the profiles with different stripping depths are calculated. The results show that the thick soft superficial layers can significantly decrease peak ground accelerations and increase characteristic periods, resulting in serious “low-fat” response spectra. The situation can be greatly improved by stripping off the soft superficial layers. After stripping off the thick soft superficial silt layers, if stripping is continued further, the variation in the superficial amplification ratios of peak accelerations and superficial characteristic periods will no longer be drastic, and the superficial amplification ratios and characteristic periods both tend to be mostly the same. The relative deviation of the amplification ratio of peak ground acceleration between a profile stripped and that without stripping can be 143%, and it can be 83% for characteristic period. It is advisable to strip off thick soft superficial layers to perform site response analysis, and the shear force at the bottom of the silt should be considered in engineering based on local seismic activity level, and the silt’s and the structure’s physical parameters.

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