Project’s Detail

PENGARUH PENAMBAHAN PASIR KUARSA FORMASI BALIKPAPAN TERHADAP KUAT GESER TANAH LEMPUNG FORMASI KAMPUNG BARU

Abstrak (Abstracts)

Balikpapan City has several formations. One of them is the Kampung Baru formation and Balikpapan formation. The clay soil of the Kampung Baru formation has low to medium plasticity, so it needs to be improved by adding quartz sand to the Balikpapan formation to improve the soil structure. The purpose of this study was to determine the effect of sand mixture on clay soil on direct shear strength. This research will be conducted in June 2023 and will last for 2 months. Data processing is carried out in the laboratory to test the physical and mechanical properties of the soil with a mixture percentage of 0%, 10%, 20%, 30%, 40%, 50% sand, respectively. Physical tests carried out include sieve analysis tests, atterberg limits tests, moisture content tests, volume weight tests and specific gravity tests. The laboratory test results obtained the USCS classification system of soil including fine-grained passed filter No.200 = 51.97% with a value of Liquit Limit (LL) = 47.57%, Plastic Index (PI) = 22.7% then the soil belongs to the CL group (low to medium plasticity clay). The addition of sand mixing proves the soil shear strength of the direct shear strength test with a decrease in cohesion (c), namely original soil 0% c = 2.7425 kg/cm2, 10% sand c = 2.538 kg/cm2, 20% sand c = 2.3481 kg/cm2, 30% sand c = 2.1064 kg/cm2, 40% sand c = 2.0891 kg/cm2, 50% sand c = 2.0337 kg/cm2. Meanwhile, the value of deep shear angle (φ) has increased, namely original soil 0% φ = 32.182 kg/cm2, 10% sand φ = 59.499 kg/cm2, 20% sand φ = 73.99 kg/cm2, 30% sand φ = 80.07 kg/cm2, 40% sand φ = 81.038 kg/cm2, 50% sand φ = 85.276 kg/cm2. The cohesion value decreases as the percentage of quartz sand of Balikpapan formation increases, while the angle of deep shear increases when the percentage of quartz sand of Balikpapan formation increases. The use of quartz sand in Balikpapan formation as a stabilization factor for clay soils tends to have the same effectiveness in improving the physical and mechanical properties of clay soils. Kota Balikpapan memiliki beberapa formasi. Salah satunya adalah formasi Kampung Baru dan formasi Balikpapan. Tanah lempung formasi Kampung Baru memiliki plastisitas rendah sampai sedang, sehingga perlu dilakukan perbaikan dengan cara menambahkan pasir kuarsa formasi Balikpapan untuk memperbaiki struktur tanahnya. Tujuan penelitian ini untuk mengetahui pengaruh campuran pasir pada tanah lempung terhadap kuat geser langsung. Penelitian ini dilaksanakan pada bulan Juni tahun 2023 berlangsung selama 2 bulan. Pengolahan data dilakukan di laboratorium untuk menguji sifat fisik dan mekanik tanah dengan masing-masing persentase campuran 0%, 10%, 20%, 30%, 40%, 50% pasir. Pengujian fisik yang dilakukan meliputi uji analisa saringan, uji atterberg limits, uji kadar air, uji berat volume dan uji berat jenis. Hasil uji laboratorium didapatkan sistem klasifikasi USCS tanah termasuk berbutir halus lolos saringan No.200 = 51,97% dengan nilai Liquit Limit (LL) = 47,57%, Plastis Indeks (PI) =22,7% maka tanah termasuk kelompok CL (lempung plastisitas rendah sampai sedang).Penambahan pencampuran pasir membuktikan kuat geser tanah dari uji kuat geser langsung dengan penurunan kohesi (c) yaitu tanah asli 0% c = 2,7425 kg/cm2, 10% pasir c = 2,538 kg/cm2, 20% pasir c = 2,3481 kg/cm2, 30% pasir c = 2,1064 kg/cm2, 40% pasir c= 2,0891 kg/cm2, 50% pasir c = 2,0337 kg/cm2. Sedangkan untuk nilai sudut geser dalam (φ) mengalami kenaikan yaitu tanah asli 0% φ = 32,182 kg/cm2, 10% pasir φ = 59,499 kg/cm2, 20% pasir φ = 73,99 kg/cm2, 30% pasir φ = 80,07 kg/cm2, 40% pasir φ = 81,038 kg/cm2, 50% pasir φ = 85,276 kg/cm2. Nilai kohesi mengalami penurunan seiring bertambahnya presentase pasir kuarsa formasi Balikpapan, sebaliknya sudut geser dalam naik ketika presentase pasir kuarsa formasi Balikpapan naik. Penggunaan pasir kuarsa formasi Balikpapan sebagai behan stabilisasi tanah lempung cenderung memiliki efektifitas yang sama dalam memperbaiki sifat fisik dan sifat mekanis tanah lempung.

Keyword : Keywords: soil shear strength, quartz sand, soil stabilization, clay

Nilai Properti

Penulis : INDAH NUR SAFITRI, NIM : 922020005, Penerbit : Politeknik Negeri Balikpapan, Program Studi : TEKNIK SIPIL, Tahun : 2023, Bahasa : Indonesia, Jenis Penelitian : Tugas Akhir, Lokasi : Prepustakaan Poltekba,

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