PENGARUH PENAMBAHAN POTONGAN BAN BERSERAT NILON DAN SEMEN PORTLADN TERHADAP NILAI CBR TANAH LEMPUNG

 Berdasarkan hasil survei lapangan di Desa Tewang Rangkang, Kecamatan Pulau Malan, Kabupaten Katingan kondisi jalan didaerah tersebut didominasi oleh tanah lunak. Tanah lunak sangat berpengaruh didalam pada pembangunan kontruksi pondasi jalan dan konstruksi pondasi bangunan. Penelitian ini bertujuan untuk menganalisis hasil stabilisasi tanah dengan penambahan potongan ban berserat nilon dan semen portland dengan variasi penambahan campuran 5% semen portland dan 5%; 7,5%; 10%; 12%; 15% untuk potongan ban berserat nilon dengan masa pemeraman 7 Hari. Hasil pengujian sifat fisik tanah asli diperoleh nilai, kadar air (w) = 44,12%; berat isi =1,30 g/cm3; berat jenis(Gs) = 2,70; LL = 41,00; PL =24,04; IP =16,96; SL =15,89. Menurut sistem USCS dari hasil pemeriksaan batas cair (LL) dan indeks plastisitas (PI) didapat bahwa diklasifikasikan sebagai tanah berlempung dalam kelompok A-7-5 (8). Hasil  pengujian sifat mekanik tanah asli menunjukan bahwa nilai CBR tanah asli 2,09%; berat isi kering  = 1,572%; kadar air optimum (OMC) = 19,82%. Campuran potongan ban berserat nilon dan semen portland berdampak pada peningkatan nilai CBR. Penambahan variasi campuran 5% semen portland dan 5%; 7%; 10%; 12,5%; 15% menghasilkan nilai CBR rencana yang meningkat sebesar 2,90%; 4,90%; 4,08%; 3,40%; 2,20%; 2,15% di pemeraman 7 hari. Nilai CBR terbesar terjadi pada penambahan semen portland 5% dan 5% potongan ban berserat nilon, pada pemeraman 7 hari yaitu sebesar 5,30%, CBR meningkat 154,55% dari nilai CBR tanah asli.   Based on the results of a field survey in Tewang Rangkang Village, Pulau Malan District, Katingan Regency, the road conditions in the area are dominated by soft soil. Soft soil is very influential in the construction of road foundations and construction of building foundations. This study aims to analyze the results of soil stabilization with the addition of pieces of nylon fiber tires and portland cement with variations in the addition of a mixture of 5% portland cement and 5%; 7.5%; 10%; 12%; 15% for nylon fiber tires with a curing period of 7 days. The results of testing the physical properties of the original soil obtained values, water content (w) = 44.12%; fill weight = 1.30 g/cm3; specific gravity (Gs) = 2.70; LL = 41.00; PL = 24.04; IP = 16.96; SL = 15.89. According to the USCS system, the results of the examination of the liquid limit (LL) and the plasticity index (PI) were found to be classified as loamy soils in group A-7-5 (8). The results of testing the mechanical properties of the original soil showed that the CBR value of the original soil was 2.09%; dry weight (γdmax) = 1.572%; optimum water content (OMC) = 19.82%. The mixture of nylon fiber tires and portland cement has an impact on increasing the CBR value. The addition of a mixture variation of 5% portland cement and 5%; 7%; 10%; 12.5%; 15% resulted in an increased plan CBR value of 2.90%; 4.90%; 4.08%; 3.40%; 2.20%; 2.15% at 7 days curing. The largest CBR value occurred in the addition of 5% portland cement and 5% nylon fiber tire pieces, at 7 days curing which was 5.30%, the CBR increased by 154.55% from the original soil CBR value.