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Contact Name
Ali Awaludin
Contact Email
ali.awaludin@ugm.ac.id
Phone
+6287852654297
Journal Mail Official
jcef.ft@ugm.ac.id
Editorial Address
Jl. Grafika No.2 Kampus UGM, Yogyakarta 55281
Location
Kab. sleman,
Daerah istimewa yogyakarta
INDONESIA
Journal of the Civil Engineering Forum
ISSN : 25811037     EISSN : 25495925     DOI : https://doi.org/10.22146/jcef
Core Subject : Engineering,
JCEF focuses on advancing the development of sustainable infrastructure and disseminating conceptual ideas and implementing countermeasures, particularly in the tropics, which are vulnerable to disasters. Specifically, we look to publish articles with the potential to make real-world contributions to improving both local communities and countries readiness for and responsiveness to natural and human-made disasters. The particular emphasis of JCEF is given to the civil & environmental engineering researches associated with natural disasters such as geo-disaster (earthquake, landslide, and volcanic eruption), water-related disaster (flood, debris flow, coastal disaster, and tsunami), and human-made disasters such as soil, water, and air pollution and water scarcity. Articles describing the topics of disaster risk reduction techniques, disaster early warning system, climate change adaptation, vulnerability analysis and trends, pre and/or post-disaster reconstruction and rehabilitation planning and management, forensic engineering, the socio-engineering approach for the countermeasures, or water reuse and recycle are particularly encouraged.
Articles 151 Documents
Effect of Relative Density Variation on The Effectiveness of Fly Ash in Stabilization of Sandy Soils for Liquefaction Mitigation Wangsawitana , Yunan Yakuta; Fauzan , Muhammad; Putra, Heriansyah; Erizal; Simatupang, Minson
Journal of the Civil Engineering Forum Vol. 12 No. 3 (September 2026)
Publisher : Department of Civil and Environmental Engineering, Faculty of Engineering, Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22146/jcef.26551

Abstract

Indonesia is highly vulnerable to earthquakes that can trigger soil liquefaction, particularly in coastal regions where saturated sandy soils with low relative densities are prevalent. This study investigated the influence of varying Class C fly ash contents (5%, 10%, and 15%), relative densities (50%, 70%, and 90%), and curing periods (7 and 14 days) on the unconfined compressive strength of fully saturated sandy soils as a liquefaction mitigation approach. The methodology included physical soil characterization, sample preparation with specific fly ash and relative density variations, and unconfined compressive strength testing after the curing period. The results demonstrated that increasing the fly ash content, relative density, and curing time significantly enhanced the strength of the samples. The highest strength occurred at 15% fly ash and 90% relative density, with 426.22 kPa (7 days) and 438.57 kPa (14 days). The most notable improvement occurred with an increase in fly ash content from 5% to 10% and relative density from 50% to 70%. Fly ash was more effective at enhancing the strength of sandy soil by promoting interparticle cementation, whereas excessive compaction tended to disrupt the soil structure and generate fine particles that reduced cohesion, as evidenced by the UCS test results and SEM observations. The most significant strength gain between 7 and 14 days was observed at 50% relative density and 5% fly ash, with a twofold increase. The combination of 10% fly ash and 70% relative density was optimal for field implementation, as it yielded strength values exceeding the liquefaction resistance thresholds, while maintaining practical compaction levels and material efficiency. A comparative cost assessment considering materials, labor, equipment, and construction time is recommended to evaluate the practical feasibility of fly ash stabilization relative to alternative ground improvement methods for Indonesian projects.