Liquefaction potential hazard study at UIN Datokarama, Palu City, Central Sulawesi

In June 2019, the Asian Development Bank approved emergency rehabilitation and reconstruction assistance (EARR) to help Indonesia rebuild better critical infrastructure damaged by the 2018 Palu-Donggala earthquake. One of the EARR sub-projects is the reconstruction of Universitas Islam Negeri (UIN) Datokarama that suffered significant damage from the combined effects of the tsunami and earthquake. The design for the building's reconstruction incorporated better principles of deconstruction, including pile foundations to ensure the facilities are earthquake, tsunami, and liquefaction resistant. This study purpose is to evaluate liquefaction potential and estimate its severity or damage potential to structures in the reconstruction site. Liquefaction potential will be assessed in two ways, first by using soil deposits grain sizes distribution method from Japan technical standards for port and harbour facilities and second by safety factor against liquefaction (FOS) method using the SPT-based liquefaction triggering analysis with the revised magnitude scaling factor (MSF) relationship by Idriss and Boulanger. Liquefaction Potential Index (LPI) from Iwasaki will be used for estimating liquefaction severity. The analysis is performed on dataset taken from 6 boreholes in location dominated by saturated sandy soil and shallow ground water. Based on the result, liquefaction potentially triggered at various depth with consistent LPI index at > 15, The reconstruction site has a very high liquefaction risk

Liquefaction potential analysis in Yogyakarta – Bawen Toll Road section 3

The Yogyakarta – Bawen Toll Road construction is one of the National Strategic Projects because it passes through four regencies in Central Java Province and the Special District of Yogyakarta. As the general consideration for infrastructure planning, it was required to consider preventing damages due to natural disasters, including liquefaction caused by an earthquake. The study area has a shallow groundwater table (<10 m), and earthquakes often occurred. Geological conditions showed that the lithologies in Yogyakarta – Bawen Toll Road Section 3 is dominated by silty sand, sandy silt, and gravel. This study aimed to analyze the liquefaction potential in the construction of Yogyakarta – Bawen Toll Road Section 3, especially STA 44+600 – 52+800. The potential liquefaction analysis is calculated using the Simplified Procedure Method based on Standard Penetration Test data. Furthermore, Liquefaction Potential Index (LPI) is applied to determine the level of liquefaction potential. The most central part of the study area indicated no liquefaction potential. On the contrary, the northern and southern parts are indicated to have liquefaction potentials ranging from high to very high. According to the analysis results, it is recommended to have a mitigation plan against liquefaction in the area study

Liquefaction potential evaluation on reconstruction project of irrigation canal in the Jono Oge and Lolu Village

In Indonesia's liquefaction history, the province of Central Sulawesi was severely affected in several locations when a 7.5 Mw earthquake occurred in September 2018. This study aims to evaluate the liquefaction potential and generate the liquefaction hazard map in the reconstruction project of the Gumbasa Irrigation Canals passed through Jono Oge Village and Lolu Village, closely related to the liquefaction event in the Sigi Regency area. Using the simplified procedure method by Idriss and Boulanger, the Liquefaction Factor of Safety (FOS) was calculated for each layer of soil from thirteen (13) locations of soil investigation test at the end of 2021 by the Ministry of Public Works and Housing. Furthermore, it was followed by calculating the Liquefaction Potential Index (LPI) and Liquefaction Severity Index (LSI). The analysis results show that the construction work area has the liquefaction potential with the observed groundwater level. It is mapped on irrigation canals along the Jono Oge Village and Lolu Village to know the critical segment of the irrigation project. Hereafter, an irrigation canal segment named BGKN-45 to BGKN-46 in Jono Oge required a specific mitigation plan to prevent damage from liquefaction in the future

Nonlinear Analysis for Investigating Seismic Performance of a Spun Pile-Column of Viaduct Structure

Slab-on-pile SOP viaducts have been constructed on several highways and railways in Indonesia, but there are certain doubts about some practical structural seismic design concepts. Therefore, this study aims to investigate the seismic performance of a single spun pile column for the SOP viaduct using nonlinear analysis. The essential variables used include the effect of top pile reinforced concrete infill treatment, soil-pile structure interaction (SPSI), and different response modification factors (R). Moreover, the single spun pile column was designed as a macro model with a force-based beam-column element having a fiber section in the plastic hinge. The static pushover analysis and quasi-static cyclic were also conducted to determine the displacement limit state and the equal viscous damping, respectively. Furthermore, seven pairs of ground motion excitations were used to investigate seismic performance in line with ASCE 7-10 and ASCE 61-14. The results showed that the implementation of the top-pile reinforced concrete infill treatment slightly reduced seismic response but evoked more severe pile curvature in the embedded zone. In addition, the behavior and seismic performance were slightly better than those without treatment when considering the SPSI. This study recommends the spun pile column for the SOP viaduct with a response modification factor of 1.5 to avoid probable brittle failure occurrence under earthquake load. Doi: 10.28991/CEJ-2023-09-07-02 Full Text: PD

Liquefaction potential hazard study at UIN Datokarama, Palu City, Central Sulawesi

In June 2019, the Asian Development Bank approved emergency rehabilitation and reconstruction assistance (EARR) to help Indonesia rebuild better critical infrastructure damaged by the 2018 Palu-Donggala earthquake. One of the EARR sub-projects is the reconstruction of Universitas Islam Negeri (UIN) Datokarama that suffered significant damage from the combined effects of the tsunami and earthquake. The design for the building's reconstruction incorporated better principles of deconstruction, including pile foundations to ensure the facilities are earthquake, tsunami, and liquefaction resistant. This study purpose is to evaluate liquefaction potential and estimate its severity or damage potential to structures in the reconstruction site. Liquefaction potential will be assessed in two ways, first by using soil deposits grain sizes distribution method from Japan technical standards for port and harbour facilities and second by safety factor against liquefaction (FOS) method using the SPT-based liquefaction triggering analysis with the revised magnitude scaling factor (MSF) relationship by Idriss and Boulanger. Liquefaction Potential Index (LPI) from Iwasaki will be used for estimating liquefaction severity. The analysis is performed on dataset taken from 6 boreholes in location dominated by saturated sandy soil and shallow ground water. Based on the result, liquefaction potentially triggered at various depth with consistent LPI index at > 15, The reconstruction site has a very high liquefaction risk

Liquefaction potential evaluation on reconstruction project of irrigation canal in the Jono Oge and Lolu Village

In Indonesia's liquefaction history, the province of Central Sulawesi was severely affected in several locations when a 7.5 Mw earthquake occurred in September 2018. This study aims to evaluate the liquefaction potential and generate the liquefaction hazard map in the reconstruction project of the Gumbasa Irrigation Canals passed through Jono Oge Village and Lolu Village, closely related to the liquefaction event in the Sigi Regency area. Using the simplified procedure method by Idriss and Boulanger, the Liquefaction Factor of Safety (FOS) was calculated for each layer of soil from thirteen (13) locations of soil investigation test at the end of 2021 by the Ministry of Public Works and Housing. Furthermore, it was followed by calculating the Liquefaction Potential Index (LPI) and Liquefaction Severity Index (LSI). The analysis results show that the construction work area has the liquefaction potential with the observed groundwater level. It is mapped on irrigation canals along the Jono Oge Village and Lolu Village to know the critical segment of the irrigation project. Hereafter, an irrigation canal segment named BGKN-45 to BGKN-46 in Jono Oge required a specific mitigation plan to prevent damage from liquefaction in the future

Liquefaction potential analysis in Yogyakarta – Bawen Toll Road section 3

The Yogyakarta – Bawen Toll Road construction is one of the National Strategic Projects because it passes through four regencies in Central Java Province and the Special District of Yogyakarta. As the general consideration for infrastructure planning, it was required to consider preventing damages due to natural disasters, including liquefaction caused by an earthquake. The study area has a shallow groundwater table (<10 m), and earthquakes often occurred. Geological conditions showed that the lithologies in Yogyakarta – Bawen Toll Road Section 3 is dominated by silty sand, sandy silt, and gravel. This study aimed to analyze the liquefaction potential in the construction of Yogyakarta – Bawen Toll Road Section 3, especially STA 44+600 – 52+800. The potential liquefaction analysis is calculated using the Simplified Procedure Method based on Standard Penetration Test data. Furthermore, Liquefaction Potential Index (LPI) is applied to determine the level of liquefaction potential. The most central part of the study area indicated no liquefaction potential. On the contrary, the northern and southern parts are indicated to have liquefaction potentials ranging from high to very high. According to the analysis results, it is recommended to have a mitigation plan against liquefaction in the area study

ANALISIS PERILAKU TIMBUNAN DENGAN PERKUATAN GEOSINTETIK MENGGUNAKAN SOFTWARE PLAXIS

The problems on the road embankment soil structure located above the soft soil with high water table require practical and effective solutions. The high operational loading and the soft base soil with its soaked condition causing nonuniform settlement which endanger the stabilization of the road. Geosynthetic reinforcement expected to be the best solution by relying on the ability of tensile strength. Stability of reinforced embankment structure influenced by several aspects, namely the design based on the collapse analysis and selection of appropriate reinforcing material, control in field either during the installation of reinforcing materials, stockpiling and maintenance for a certain period. This analysis reviewed stress-strain behavior of geosynthtic as reinforcement and safety factor analysis that happens to construction of embankment Toll Road Semarang � Solo especially on the Stage I in Part Semarang � Bawen Section I: Tembalang � Gedawang based on finite element method using software PLAXIS. The soil and geosynthetiic modeled two dimensional as plane strain with Mohr � Coulomb material model as elastoplastic non linear. Comparison made between embankment with and without reinforcement to determine the effectiveness of the geosynthetic use. This analysis was done with variations of the reinforcement strength and value of interface based on variations of geosynthetic type. Traffic load and earthquake simulated to determine the stability of embankment on the operational condition. The bearing capacity of subgrade in this construction equals to 1035,524 kN/m2. It is compared with the embankment load, the subgrade is capable of receiving 4 meters of embankment height, but the embankment carried out in stages to easier implementation. 164,76 days as result of the duration consolidation is used as a validation data of the finite element analysis. Installation of reinforcement can replace the low shear strength when consolidation process or during increasing of pore water pressure, but did not reduce total settlement due to the embankment load. Variations in the value of normal stiffness and an interface based on the variations of materials type greatly influence the results of the analysis and output of the PLAXIS software. In this study, geotextile non woven reinforcement able to rely on the stability stress and strain of the material as well as increase the safety factor significantly, from 1,27 as safety factor of embankment without reinforcement to 1,35

Numerical model for investigating seismic performance of Prestressed Hollow Concrete (PHC) piles with Fiber section element

In the medium to high seismic zone, prestressed hollow concrete (PHC) pile for structural foundation should be designed with elastic behavior due to low ductility and dissipated energy. However, some Indonesian practical engineer has chosen PHC pile for pile-supported slab viaduct (PSSV) with medium seismic moment-resisting frame concept in a high-risk earthquake zone. Therefore, some nonlinear numerical simulations of PSSV structure in medium to high seismic zone need to be conducted to investigate its seismic performance. In the initial stage, a numerical model for investigating the seismic performance of PHC pile under flexural test was conducted. By implementing an appropriate plastic hinge length of forced beam-column with hinge elements, the flexural behavior of PHC piles to be simulated under both monotonic and cyclic loading. The fiber section was adopted to accommodate non-linear behaviour of material in the PHC pile cross section. As the results, the skeleton curves, the sectional strain distributions, and the hysteresis curves have good agreement results compared with the experimental results. Furthermore, based on the equal damping ratio calculation of the hysteresis curve, the PHC pile only achieve low energy dissipation, though the ductility capacity around 3. Finally, this numerical model approach could be adopted in the non-linear simulation of PSSV structure under seismic load

Numerical model for investigating seismic performance of Prestressed Hollow Concrete (PHC) piles with Fiber section element

In the medium to high seismic zone, prestressed hollow concrete (PHC) pile for structural foundation should be designed with elastic behavior due to low ductility and dissipated energy. However, some Indonesian practical engineer has chosen PHC pile for pile-supported slab viaduct (PSSV) with medium seismic moment-resisting frame concept in a high-risk earthquake zone. Therefore, some nonlinear numerical simulations of PSSV structure in medium to high seismic zone need to be conducted to investigate its seismic performance. In the initial stage, a numerical model for investigating the seismic performance of PHC pile under flexural test was conducted. By implementing an appropriate plastic hinge length of forced beam-column with hinge elements, the flexural behavior of PHC piles to be simulated under both monotonic and cyclic loading. The fiber section was adopted to accommodate non-linear behaviour of material in the PHC pile cross section. As the results, the skeleton curves, the sectional strain distributions, and the hysteresis curves have good agreement results compared with the experimental results. Furthermore, based on the equal damping ratio calculation of the hysteresis curve, the PHC pile only achieve low energy dissipation, though the ductility capacity around 3. Finally, this numerical model approach could be adopted in the non-linear simulation of PSSV structure under seismic load