Electronic Theses and Dissertation

Penelitian ini bertujuan untuk mengetahui karakteristik fisis dan perilaku
pemadatan tanah endapan pasca banjir bandang di Kabupaten Aceh Tamiang
sebagai dasar penilaian potensi pemanfaatannya sebagai material timbunan dan
tanah dasar konstruksi. Pengujian dilakukan terhadap enam sampel tanah terganggu
yang diambil dari tiga kecamatan, yaitu Karang Baru, Kuala Simpang, dan
Kejuruan Muda. Analisis laboratorium meliputi pengujian kadar air, berat jenis,
batas Atterberg, analisis saringan, analisis hidrometer, serta pengujian pemadatan
menggunakan metode Standard Proctor sesuai ASTM D698. Hasil pengujian
menunjukkan bahwa seluruh sampel didominasi oleh butiran halus dengan
persentase lolos saringan No.200 lebih dari 58% dan berat jenis berkisar antara
2,55–2,63. Berdasarkan sistem klasifikasi AASHTO, tanah termasuk kelompok A
7-5 dan A-7-6, sedangkan berdasarkan sistem USCS, tanah diklasifikasikan sebagai
CL dan CH sesuai karakteristik masing-masing lokasi. Nilai kadar air optimum
(OMC) berada pada rentang 22,82%–27,81%, sedangkan nilai berat isi kering
maksimum (MDD) berkisar antara 1,41–1,54 g/cm³. Variasi nilai tersebut
menunjukkan bahwa setiap lokasi memiliki karakteristik pemadatan yang berbeda
akibat perbedaan distribusi ukuran butir, komposisi material halus, dan tingkat
plastisitas tanah endapan. Secara teknis, tanah endapan ini memiliki kemampuan
pemadatan yang terbatas dan sensitif terhadap perubahan kadar air, sehingga
penggunaannya sebagai bahan timbunan atau subgrade memerlukan pengendalian
kadar air yang baik dan, apabila diperlukan, stabilisasi tanah untuk meningkatkan
daya dukung. Hasil penelitian ini diharapkan dapat menjadi acuan teknis dalam
rehabilitasi pascabencana serta pemanfaatan kembali material endapan di wilayah
terdampak.
Kata Kunci : Tanah endapan, klasifikasi tanah, pemadatan, USCS & AASHTO

This study aimed to determine the physical characteristics and compaction behavior of post-flash flood sediment in Aceh Tamiang Regency as a basis for assessing its potential use as embankment material and construction base soil. Testing was conducted on six disturbed soil samples taken from three sub-districts: Karang Baru, Kuala Simpang, and Keguruan Muda. Laboratory analysis included water content, specific gravity, Atterberg limits, sieve analysis, hydrometer analysis, and compaction testing using the Standard Proctor method according to ASTM D698. Test results showed that all samples were dominated by fines, with a percentage passing the No. 200 sieve of more than 58% and a specific gravity ranging from 2.55 to 2.63. Based on the AASHTO classification system, the soil belongs to groups A7-5 and A7-6, while under the USCS system, the soil is classified as CL and CH, depending on the characteristics of each location. The optimum water content (OMC) ranged from 22.82% to 27.81%, while the maximum dry unit weight (MDD) ranged from 1.41 to 1.54 g/cm³. These variations indicate that each location has different compaction characteristics due to differences in grain size distribution, fine material composition, and the degree of plasticity of the sedimentary soil. Technically, this sedimentary soil has limited compaction capacity and is sensitive to changes in water content. Therefore, its use as embankment or subgrade requires proper water content control and, if necessary, soil stabilization to increase bearing capacity. The results of this study are expected to serve as a technical reference for post-disaster rehabilitation and the reuse of sedimentary material in affected areas. Keywords: Sedimentary soil, soil classification, compaction, USCS & AASHTO