https://composite.ft.ung.ac.id/index.php/cj <p>Composite Journal is a Civil Engineering Journal from the Department of Civil Engineering at Universitas Negeri Gorontalo. It covers a wide area of topics, including Geotechnical Engineering, Construction Materials, Hydrology, Hydraulics, Construction Management, and Environment.</p> <p>The goal of the Composite Journal&nbsp;is to be an effective way to share high-quality research results from researchers, scientists, and engineers. The journal covers the following main areas: Advances in Composite Materials; Computational Mechanics; Foundations and Retaining Walls; Slope Stability; Soil Dynamics; Soil-Structure Interactions; Pavement Technology; Tunnels and Anchors; Site Investigation and Rehabilitation; Ecology and Land Development; Water Resources Planning, Engineering, and Management; Environmental Management; Earthquake and Tsunami Issues; Safety and Reliability (Geohazard Mitigation, Case Histories, and Practical Experiences).</p> <p>Composite Journal accepts original articles in the form of theory papers, applied papers, review papers, and case studies in all areas of civil engineering.&nbsp;</p> <p>The journal's editorial board includes researchers, academics, and scientists from Universitas Negeri Gorontalo and other universities in Indonesia.</p> <p>To submit an article, contributors can download the manuscript <a href="https://docs.google.com/document/d/1oNwe4OzvV9ZF1jyTASOs4J3HL-j6m3ms/edit?usp=sharing&amp;ouid=109492398529344873896&amp;rtpof=true&amp;sd=true">template Composite Journal</a> or contact the Editor-in-Chief at compositejournal@ung.ac.id.</p> Jurusan Teknik Sipil, Fakultas Teknik, Universitas Negeri Gorontalo en-US Composite Journal 2807-5919 https://composite.ft.ung.ac.id/index.php/cj/article/view/148 <p>Jalan Jenderal Sudirman adalah salah satu ruas jalan di Kota Gorontalo yang memiliki volume kendaraan yang besar. Keadaan ini diperparah oleh banyaknya kendaraan yang parkir di sepanjang badan jalan. Tujuan dari penelitian ini untuk mengetahui kinerja dari ruas Jalan Jendral Sudirman akibat adanya parkir di badan jalan. Dalam penelitian ini MKJI 1997 digunakan sebagai pedoman dalam menganalisis kinerja ruas jalan. Penelitian ini dilangsungkan selama 3 hari yaitu hari Selasa, 11 Juni 2024, Jumat, 14 Juni 2024, dan Sabtu, 15 Juni 2024. Hasil kondisi eksisting yang didapatkan yaitu tingkat pelayanan jalan terburuk terdapat pada hari Selasa, 11 Juni 2024 dengan nilai derajat kejenuhan sebesar 0,58 dan masuk pada kategori tingkat pelayanan jalan C, serta pada kondisi jika tidak terdapat parkir di badan jalan tingkat pelayanan meningkat menjadi 0,30 dan masuk pada kategori B. Hasil ini menunjukan bahwa kegiatan parkir di badan jalan sangat berpengaruh pada optimalnya kinerja ruas jalan.</p> Dhea Nur Amanah Hadjarati Frice Lahmudin Desei Yuliyanti Kadir Copyright (c) 2026 Composite Journal https://creativecommons.org/licenses/by-sa/4.0 2026-01-23 2026-01-23 6 1 1 10 10.37905/cj.v6i1.148 https://composite.ft.ung.ac.id/index.php/cj/article/view/171 <p>Leato Utara, located in Gorontalo City, Gorontalo Province, is a coastal area known as a tourist destination and residential centre. The increasing population in this area has led to a growing demand for clean water. As a result, most residents rely on shallow aimed to analyse the quality of groundwater in Leato Utara and asses the community’s water demand. The analysis method involved testing physical parameters (TDS, turbidity, temperature, colour, odour, and salinity), chemical parameters (iron, pH, manganese, and hardness), and microbiological parameters (Escherichia coli and Coliform) based on the Ministry of Health Regulation No. 2 of 2023. Water demand was analysed based on population data, including domestik and non-domestik water needs, water losses, and total water demand. The results indicated that shallow groundwater quality in Leato Utara varies across physical, chemical, and microbiological parameters, Physical parameters such as turbidity, temperature, colour, and salinity met the quality standards 100%, but only 33.33% of TDS samples met the standard. Chemical parameters such as pH, manganese, and iron fully met the standards, while only 33.33% of hardness results were within acceptable limits. Microbiological tests revealed that 66.67% of samples exceeded the standard for Coliform and 33.33% for E. Coli, indicating potential bacterial contamination. Water availability was found to be 28.512 liters/day, which is insufficient compared to the community’s total demand of 34.008 liters/day. Therefore, appropriate measures are needed to address this water supply issue.</p> Irana I. Koem Ibrahim Ismail Aryati Alitu Marike Mahmud Copyright (c) 2026 Composite Journal https://creativecommons.org/licenses/by-sa/4.0 2026-01-23 2026-01-23 6 1 11 19 10.37905/cj.v6i1.171 https://composite.ft.ung.ac.id/index.php/cj/article/view/173 <p>Road damage is a complex problem and can cause major losses for road users.The purpose of this study is to analyze the damage to the Molingkapoto road at the Kwandang intersection, and to examine the appropriate handling of the damage that occurs. The methods used in the study are the SDI and IRI methods. The SDI method is a visual assessment of damage conditions. In calculating the SDI value, 4 elements are used, namely % crack area, crack gap width, number of holes/100 m and depth of wheel ruts. The IRI method is the value of road surface flatness calculated from the cumulative number of ups and downs of the longitudinal profile surface divided by the distance/length of the measured surface. The IRI value in this study was taken per 100 m using the Roadlab Pro application. The results of the SDI method analysis showed good conditions of 82%, moderate 12%, minor damage 3%, and severe damage 3%. The road conditions were dominated by good conditions along 2.7 km. The results of the IRI method analysis showed very good conditions of 0%, good conditions of 68%, moderate 29%, bad 3%, and very bad 0%. The road conditions were dominated by good conditions along 4.5 km. The combination of SDI and IRI values showed that Molingkapoto road at the Kwandang intersection sta. 6+300 to sta. 9+600 was in moderate condition and only required routine maintenance.</p> Moh. Reza Jahja Frice Lahmudin Desei Yuliyanti Kadir Copyright (c) 2026 Composite Journal https://creativecommons.org/licenses/by-sa/4.0 2026-01-23 2026-01-23 6 1 20 29 10.37905/cj.v6i1.173 https://composite.ft.ung.ac.id/index.php/cj/article/view/200 <p>This study examines the early-age sulfate resistance of Class C fly ash–based geopolymer concrete (GPC) in comparison with Portland cement concrete (PCC). The research evaluates mechanical performance, mass stability, and microstructural responses after 28 days of exposure to a 5% magnesium sulfate solution. The experimental program includes material characterization, dry-mix geopolymer preparation, sulfate immersion testing, and mechanical assessments. Chemical analysis shows that the fly ash contains 65% total pozzolanic oxides and 69.68% amorphous content, confirming its high reactivity and suitability for geopolymerization. The results indicate that GPC exhibits significantly better sulfate resistance, with a minimal mass change of only +0.03%, compared with PCC, which shows a +0.72% increase due to higher sulfate penetration. Mechanically, GPC demonstrates notable improvements: compressive strength increases by 25%, and elastic modulus rises by 9–11% after exposure. In contrast, PCC experiences only a slight increase in strength, primarily attributed to temporary pore filling from gypsum and ettringite formation rather than genuine structural enhancement. Microstructural observations confirm the presence of sulfate reaction products on both materials; however, no cracking or structural damage is detected, and GPC maintains a more stable aluminosilicate network. These findings highlight GPC’s superior early-age durability and its potential as a sustainable and chemically robust alternative to PCC in sulfate-rich environments. The study provides new experimental insights into the short-term sulfate behavior of Class C fly ash–based GPC and recommends future long-term durability evaluations under extended exposure durations and field-representative conditions.</p> Hazen Masrafat Almutahir Copyright (c) 2026 Composite Journal https://creativecommons.org/licenses/by-sa/4.0 2026-01-23 2026-01-23 6 1 30 39 10.37905/cj.v6i1.200 https://composite.ft.ung.ac.id/index.php/cj/article/view/199 <p>Beton ringan <em>Celuler Lightweight Concrete (CLC)</em> adalah bahan konstruksi beton mortar aerasi dengan bobot ringan dan bisa diaplikasikan untuk berbagai konstruksi seperti dinding, lantai, timbunan jalan dan lainnya. Bahan pembuatan beton ringan CLC adalah semen dan pasir sebagai agregat halus. Penelitian ini bertujuan untuk mengetahui penggunaan pasir Dumato yang dihaluskan dan digunakan sebagai agregat halus pada beton ringan CLC. Pasir Dumato adalah material pasir gunung yang sering diambil sebagai material timbunan pada Quary disekitar Kota Gorontalo. Penelitian ini merupakan pengujian eksperimen untuk mengetahui pasir gunung Dumato sebagai pengganti pasir sungai. SNI 8640 2018 memberikan persyaratan kelas berat dan kelas mutu. Hasil pengujian menunjukkan pasir Dumato masuk zone 1. Pasir Dumato diproses dengan dihaluskan dan dicuci sehingga menghasilkan pasir halus dan lolos saringan No 50 dengan kadar lumpur berkurang hingga 0%. Perencanaan campuran 1 semen: 2 pasir dumato dan foam, dihasilkan berat volume sebesar 800 kg/m3 dan kuat tekan 3,23 Mpa. Berdasarkan SNI 8640:2018 maka masuk dikelas Mutu Bataringan non struktural kelas IIA</p> Arif Supriyatno Copyright (c) 2026 Composite Journal https://creativecommons.org/licenses/by-sa/4.0 2026-01-23 2026-01-23 6 1 40 45 10.37905/cj.v6i1.199