Yogyanta, Dwiaji Ari (2019) Perubahan Perilaku Tanah Gambut Berserat akibat Proses Dekomposisi oleh Bakteri Endogen dan Stabilisasi Campuran Kapur dan Abu Terbang. Masters thesis, Institut Teknologi Sepuluh Nopember.
![[thumbnail of 03111750010007-Master_Thesis.pdf]](http://repository.its.ac.id/style/images/fileicons/text.png) |
Text
03111750010007-Master_Thesis.pdf Restricted to Repository staff only Download (10MB) | Request a copy |
Abstract
Metode perbaikan tanah gambut berserat dengan menggunakan bahan stabilisasi telah banyak dikembangkan. Bahan stabilisasi yang telah ditemukan pada penelitian sebelumnya adalah campuran 30% kapur (CaCO3)+70% abu terbang (FA). Persentase bahan stabilisasi yang memberikan hasil yang optimum adalah 10% dari berat tanah gambut. Pada usia peram 20-45 hari, perilaku tanah gambut yang distabilisasi membaik; namun terjadi penurunan daya dukung pada usia peram 45-60 hari. Penyebabnya adalah turunnya kadar air akibat penyerapan air oleh bahan stabilisasi sehingga terjadi percepatan proses dekomposisi. Penelitian lanjutan dilakukan untuk mempercepat proses dekomposisi tanah gambut. Diperoleh hasil bahwa bakteri aerob endogen (diproduksi dari sampel tanah gambut yang diteliti) sebanyak 10% dari berat tanah gambut basah dengan waktu 28 hari memberikan hasil optimum. Hanya saja, proses dekomposisi hanya terjadi untuk serat selulosa (bakteri berjenis selulolitik) sedangkan serat lignin belum terdekomposisi dengan sempurna; hal ini berarti potensi untuk terjadinya proses dekomposisi masih ada. Dengan dasar pemikiran bahwa penurunan daya dukung tanah gambut tidak boleh terjadi apabila konstruksi telah dibangun, maka perlu dicari jenis bakteri yang dapat mendekomposisi semua jenis serat gambut sebelum pembangunan konstruksi dimulai. Studi dalam tesis ini menggunakan tanah gambut yang berasal dari Desa Bereng Bengkel, Palangkaraya, Kalimantan Tengah. Percepatan dekomposisi yang dilakukan dalam tesis ini menggunakan bakteri endogen jenis lignoselulolitik dengan persentase 10%, 20%, dan 30% . Tes kandungan serat dilakukan pada usia peram 0, 14, 28, 42, dan 56 hari untuk mengetahui laju dekomposisinya. Dari hasil tersebut didapat persentase bakteri lignoselulolitik optimum adalah 10% dari berat basah tanah gambut dengan waktu optimum 28 hari. Selanjutnya dibuat sampel baru dengan bakteri selulolitik dan lignoselulolitik optimum yang diamati pada usia peram 0, 14, 28 hari. Hasilnya menunjukkan sampel dengan menggunakan bakteri lignoselulolitik lebih efektif dalam mendekomposisi serat gambut. Kadar serat, berat volume (γt) dan specific gravity (Gs) turun masing-masing 13.3%, 6.8%, dan 7.9%; kadar air (wc) dan angka pori (e) naik sebesar 13.5% dan 11.5%. Total pemampatan, faktor pemampatan primer (a), dan faktor pemampatan sekunder (b) naik masing-masing 22.9%, 24.5%, dan 37.4%.; faktor kecepatan pemampatan sekunder (λ/b) dan sudut geser dalam (ɸ) turun sebesar 33.3% dan 27.3%.
Setelah dilakukan percepatan dekomposisi, sampel kemudian distabilisasi dengan campuran 30% kapur (CaCO3)+70% abu terbang (FA); variasi persentase bahan stabilisasi yang dipakai adalah 5%, 10%, dan 15%. Tes dilakukan pada usia stabilisasi 20, 30, 45, 60, dan 90 hari untuk mengetahui persentase bahan stabilisasi optimum. Campuran 10% bahan stabilisasi terhadap berat gambut dengan usia stabilisasi 60 hari memberikan hasil optimum yang dapat dilihat dari berat volume (γt) dan specific gravity (Gs) naik sebesar 24%, dan 68.9%; kadar air (wc) dan angka pori (e) turun sebesar 216.5% dan 10%. Total pemampatan, faktor pemampatan primer (a), dan faktor pemampatan sekunder (b) turun masing-masing 17.5%, 40.4%, dan 6.6%.; faktor kecepatan pemampatan sekunder (λ/b) dan sudut geser dalam (ɸ) naik sebesar 200% dan 6.6%.
================================================================================================================================
Soil improvement methods for fibrous peat using stabilization materials have been developed extensively. The stabilization material identified in previous studies is a mixture of 30% lime (CaCO3) and 70% fly ash (FA). The percentage of stabilization material that provides optimum results is 10% of the weight of the stabilized peat soil. At an age of 20-45 days, the behavior of the stabilized peat soil improved; however, there was a decrease in bearing capacity at 45-60 days. This is caused by a decrease in water content due to absorption by the stabilization material, which accelerates the decomposition process.
A further study was conducted to accelerate the decomposition process of peat soil. The results showed that endogenous aerobic bacteria (obtained from the peat samples studied), applied at 10% of the weight of wet peat soil over a period of 28 days, provided optimum results. However, the decomposition process only occurred for cellulose fibers (via cellulolytic bacteria), while lignin fibers had not been completely decomposed, indicating that further potential for decomposition still exists. Based on the premise that a decline in the bearing capacity of peat soil should not occur once construction has been completed, it is necessary to identify a type of bacteria that can decompose all types of peat fibers before construction begins.
This thesis uses peat soil from Desa Bereng Bengkel, Palangkaraya, Kalimantan Tengah. The acceleration of decomposition was carried out using lignocellulolytic endogenous bacteria at percentages of 10%, 20%, and 30%. Fiber content testing was performed at 0, 14, 28, 42, and 56 days to determine the rate of decomposition. Based on these results, the optimum percentage of lignocellulolytic bacteria was 10% of the wet weight of peat soil, with an optimum curing period of 28 days. New samples were then prepared using the optimum cellulolytic and lignocellulolytic bacteria, observed at 0, 14, and 28 days. The results showed that samples using lignocellulolytic bacteria were more effective at decomposing peat fibers. Fiber content, unit weight (γt), and specific gravity (Gs) decreased by 13.3%, 6.8%, and 7.9%, respectively, while water content (wc) and void ratio (e) increased by 13.5% and 11.5%. Total compression, the primary compression factor (a), and the secondary compression factor (b) increased by 22.9%, 24.5%, and 37.4%, respectively, while the rate factor for secondary compression (λ/b) and the internal friction angle (ɸ) decreased by 33.3% and 27.3%.
Following the accelerated decomposition, the samples were stabilized with a mixture of 30% lime (CaCO3) and 70% fly ash (FA), with variations in the percentage of stabilization material of 5%, 10%, and 15%. Testing was conducted at curing periods of 20, 30, 45, 60, and 90 days to determine the optimum percentage of stabilization material. A mixture using 10% stabilization material relative to the weight of the peat, with a curing period of 60 days, provided the optimum results, as shown by an increase in unit weight (γt) and specific gravity (Gs) of 24% and 68.9%, respectively, and a decrease in water content (wc) and void ratio (e) of 216.5% and 10%. Total compression, the primary compression factor (a), and the secondary compression factor (b) decreased by 17.5%, 40.4%, and 6.6%, respectively, while the rate factor for secondary compression (λ/b) and the internal friction angle (ɸ) increased by 200% and 6.6%.
| Item Type: | Thesis (Masters) |
|---|---|
| Uncontrolled Keywords: | abu terbang, bakteri dekomposer, bakteri lignoselulolitik, gambut berserat, kapur, percepatan dekomposisi, stabilisasi |
| Subjects: | T Technology > TA Engineering (General). Civil engineering (General) > TA749 Soil stabilization |
| Divisions: | Faculty of Civil, Environmental, and Geo Engineering > Civil Engineering > 22101-(S2) Master Theses |
| Depositing User: | Dwiaji Ari Yogyanta |
| Date Deposited: | 22 Jul 2026 08:30 |
| Last Modified: | 22 Jul 2026 08:30 |
| URI: | http://repository.its.ac.id/id/eprint/69113 |
Actions (login required)
 |
View Item |