14 research outputs found
Strength of Cement Treated Clay and Degradation Under Magnesium Sulphate Attack
Lumpur Sidoarjo (Lusi) is an environmental issue in Indonesia that produce wasted soils, specifically clay soils, distributed to Porong River which causes a greater problem. Cement treated clay (CTC) becomes one of the solutions to overcome the problems caused by Lusi due to its ability in improving the strength of clay soils. This paper investigates CTC with lower cement amount (C 150 kg/m3) for deep mixing marine clay for its strength and degradation due to the attack of magnesium sulphate as the main component of seawater which cause the degradation of CTC. The enhancement of soil strength is investigated by unconfined compression test (qu) and the degradation by penetration test. Water content of the specimens for both tests are arranged in its liquid limit condition (60%) and two times of its LL (120%). The result of the cement amount addition for both water content shows the enhancement of qu represented by linear and the tip resistance is increased. The characterictic of degradation for lower cement amount with close range present similar depth of deterioration, like-wise higher cement content. The value of tip resistance is not relatable with qu
Pengaruh Perubahan Kadar Air pada Sifat-Sifat Tanah Organik yang distabilisasi dengan Limbah Karbit dan Abu Ampas Tebu
Research on organic soil stabilization utilizing materials such as cement, lime, rice husk ash, fly ash, bagasse ash to change soil shear behavior has been widely carried out to this date. However, not many researchers have studied the changes in water content in organic soils that have been stabilized with such materials, especially on the changes in soil physical properties. This study aims to find out the effect of changes in water content in physical properties including: volume weight (γ), specific gravity (G), water content (w), void ratio (e), degree of acidity (pH) and content organic (O). A series of tests was conducted, namely the chemical composition of: organic soil test (TO), carbide waste (CCR), and bagasse ash (AAT), and testing for the physical properties of organic soil. Further, additional material (60% CCR and 40% AAT) was added to the soil in proportions: 5, 10, 15, 20, 25 and 30% combined with different initial water contents (498, 548 and 598%) and curing time: 7, 14, 21 and 36 days. Then, we conducted test for physical properties of the soil that has been stabilized. The physical and chemical properties of the soil change subject to added material content and ripening time. At high water content, the change is more significant than at lower water content. The volume weight, specific gravity, and acidity of the soil increases while the void ratio and soil organic content decrease. The optimal content of added material is 20% with an optimal time of curing 21 day
KESESUAIAN DAN DAYA DUKUNG WISATA PESISIR DI KAWASAN EKONOMI KHUSUS TANJUNG LESUNG KABUPATEN PANDEGLANG PROVINSI BANTEN
Pemanfaatan ruang wisata harus memperhatikan kesesuaian dan daya dukung sumberdaya dan lingkungan dimana aktivitas wisata itu berada. Kesesuaian dan daya dukung wisata akan memberikan gambaran daya tampung wisata pesisir yang akan dikembangkan pada suatu kawasan wisata. Tujuan penelitian ini adalah untuk menentukan kesesuaian dan daya dukung wisata pesisisr di Kawasan Ekonomi Khusus (KEK) Tanjung Lesung. Kesesuaian dan daya dukung wisata pesisir yang dianalisis adalah rekreasi pantai, banana boat, selam, snorkeling dan memancing, di 5 stasiun pengamatan.  Parameter yang digunakan untuk analisis spasial kesesuaian yaitu parameter indeks kesesuaian wisata (IKW) yang kemudian dizonasi dengan menggunakan multi criteria analysis (MCA) melalui kalkulasi jarak spasial (Euclidean distance) untuk mendapatkan zona-zona secara spasial dan luasnya. Perhitungan model matematika Boullon (Boullons Carrying Capacity Mathematical Model atau BCCMM) digunakan untuk analisis daya dukung. Dari hasil analisis daya dukung untuk masing-masing zona dapat diketahui dari nilai basic carrying capacity (BCC), potential carrying capacity (PCC) dan real carrying capacity (RCC). Hasil perhitungan nilai RCC pada zona wisata didapatkan jumlah daya tampung wisatawan per hari untuk aktivitas rekreasi pantai (5.323 orang), banana boat (847 orang), selam (662 orang), snorkeling (1.633 orang) dan memancing (6.286 orang). Dengan diketahuinya daya dukung wisatawan di setiap zona dan aktivitas wisata di KEK Tanjung Lesung, diharapkan semua pemangku kepentingan dapat menjadikannya pedoman dan arah pelaksanaan pembangunan zona wisata sesuai dengan kebijakan yang sudah ditetapkan agar tercapainya keberlanjutan di masa yang akan datang.Kata Kunci : daya dukung, kesesuaian, wisata pesisir, zonasi
Analisa Pondasi dan Potensi Likuifaksi Pembangunan Laboratorium dan Gedung Fakultas Universitas Atma Jaya Yogyakarta
Laboratorium Teknik Sipil dan Fakultas Teknobiologi Universitas Atma Jaya Yogyakarta, berkembang sangat pesat seiring dengan perkembangan ilmu pengetahuan dan penelitian. Alat laboratorium, mahasiswa dan peneliti yang cukup besar melakukan aktifitas praktikum dan penelitian, sehingga ruang laboratorium, ruang kelas gedung lama tidak memadai lagi dan akan dibangun gedung baru yang lebih memadai untuk proses belajar mengajar, penelitian dan pengabdian masyarakat yang layak dan nyaman. Pembangunan membutuhkan informasi lapisan tanah pendukung untuk kestabilan dan kekokohan bangunan, memperkirakan profil tanah, daya dukung tanah, parameter tanah, dan potensi likuifaksi untuk rekomendasi pondasi bangunan. Informasi lapisan tanah pendukung diperoleh dari serangkaian uji tanah di lapangan dengan pengeboran sampai kedalaman 30m dan sondir dengan kekuatan 10 ton, untuk memperoleh profil dan sample tanah. Uji di laboratorium dilakukan untuk mendapatkan parameter tanah. Analisa daya dukung dan analisa potensi likuifaksi akan di rekomendasikan untuk perancangan. Hasil analisa memperoleh daya dukung bored pile diameter 60cm dan 80cm pada kedalaman -7,0m sebesar 40ton dan 60ton, potensi likuifaksi dengan pertimbangan gempa terkuat yang pernah terjadi, pada kedalaman sekitar -17,50m sampai -20,0m dengan Liquefaction Severity Number 7,36 dan penurunan maksimal sebesar 11,87 cm, yang berarti terjadi kerusakan minor
PENGARUH WAKTU CURING TERHADAP STABILITASI TANAH DASAR LEMPUNG MENGGUNAKAN POLIMER
ABSTRAKTanah lempung lunak tersebar di beberapa wilayah di Indonesia. Umumnya, tanah lempung lunak sifat mekanik yang buruk sehingga tidak cocok digunakan sebagai tanah dasar. Stabilisasi terhadap lapisan tanah dasar untuk pembangunan jalan merupakan salah satu solusi untuk mengatasi masalah yang terjadi pada tanah lunak. Polimer adalah bahan tambah masih dikembangkan untuk stabilisasi tanah dasar di Indonesia. Polimer memiliki potensi menggantikan semen dan kapur sebagai bahan tambah tradisional. Pada penelitian ini akan dibahas mengenai pengaruh waktu curing terhadap sifat fisik tanah dan sifat mekanik tanah dasar yang distabilisasi oleh polimer bila dibandingkan dengan tanah asli. Benda uji diperam selama 2, 4, 6, 9, 18, 24, 48,72 jam dan 7 hari. Hasil penelitian menunjukkan adanya perbaikan dengan menurunnya nilai indeks plastisitas dan kadar air. Nilai kuat tekan bebas mengalami kenaikan sebesar 10% setelah di lakukan pemeraman selama 7 hari.Kata Kunci : Tanah dasar, waktu curing, polimer, indeks plastisitas, kuat tekan beba
Pengaruh Kadar Air Pada Parameter Geser Tanah Organik yang Distabilisasi dengan Limbah Karbit dan Abu Ampas Tebu
Tanah organik terbentuk oleh pelapukan tumbuhan dan binatang yang memiliki sifat-sifat fisika dan
mekanika sangat buruk. Oleh sebab itu, perbaikan tanah organik perlu diupayakan. Penelitian ini
bertujuan untuk mengkaji efektifitas bahan stabilisator limbah karbit (CCR) dan abu ampas tebu
(AAT) untuk stabilisasi tanah organik, dan melakukan investigasi mengenai pengaruh kadar air
terhadap perubahan parameter geser tanah organik yang distabilisasi dengan CCR dan AAT. Untuk
mencapai tujuan tersebut dilakukan serangkaian pengujian laboratorium. Pertama pengujian
komposisi kimia tanah organik, limbah karbit, dan abu ampas tebu. Kedua pengujian sifat mekanika
tanah yang meliputi pengujian kohesi dan sudut gesek dalam tanah asli maupun tanah yang
distabilisasi CCR dan AAT. Tanah organik dicampur dengan bahan tambah (60%CCR + 40%AAT)
dengan proporsi : 5,10,15,20,25, dan 30% pada kadar air yang berbeda (468%, 518%, dan 568%)
dan diperam dalam waktu : 7,14,21 dan 36 hari. Kemudian tanah yang sudah distabilisasi diuji geser
langsung untuk menentukan parameter geser. Hasil penelitian menunjukkan bahwa kohesi (c) dan
sudut gesek dalam (Ï•) meningkat proporsional dengan peningkatan kadar bahan tambah. Zona aktif
terlihat pada kadar bahan tambah antara 10 s.d. 20%, yang berarti kadar bahan tambah optimum
terjadi pada proporsi 20%. Peningkatan parameter geser tersebut juga proporsional terhadap waktu
pemeraman. Sampai dengan waktu peram 36 hari, parameter geser terus meningkat. Namun
demikian perubahan kadar air tidak banyak berpengaruh pada peningkatan parameter geser tanah
yang distabilisasi
Effect of Organic Content and Cement Quantity on The Shear Behavior of Artificially Cemented Soil
Most of the soil in the universe contain organic matter that results on the negative effects on the shear behavior of soil. The objective of this research is to study the effect of organic content and proportion of cement of artificially cemented soil. A compaction and direct shear test without curing period were undertaken on the soil with 6, 11, 16, and 21% organic content. Direct shear test results shows that the soil cohesion decrease and internal friction angle slightly increase as increasing of organic content. The direct shear test of artificially cemented soil with 21, 28, 42, and 56 curing time was then performed to investigate the effect of cement quantity on the shear behavior of cemented soil. The cement content was 25, 50, 75, and 100 kg/m3. The more cement quantity added to the soil, cohesion and friction angle of artificially cemented soil improves. There is also improvement of the shear stress due to the increase of cement proportion. Similarly, shear strength of stabilized soil improves inherent with curing period due to the short and long-term pozzolanic reactions
Effect of Water Content on the Characteristics of Bagasse Ash-Calcium Carbide Residue Stabilized Organic Soil
Research about chemically stabilized organic soil to improve shear strength has been done by many researchers. However, they have never undertaken the research about the the effect of water content on physical and chemical characteristics of stabilized organic soil. Aset of experimental program performed in this research were chemical composition of organic soil (OS), calcium carbide residue (CCR), and bagasse ash (BA); also the physical characteristics of OS. The admixture (60% CCR + 40% BA) was added to the soil with proportion 5, 10, 15, 20, 25 and 30% with various water content, and the samples were cured in 7, 14, 21, and 36 days- curing time. Then, the experiment of physical properties of the stabilized soil was undertaken. The physical characteristics of the stabilized soil change with respect to the water content, quantity of admixture and the curing times. On the high water content, the changes of the physical properties are more significant compared to that on the lower water content. The unit weight, specific gravity, and the degree of acidity increase whereas void ratio and organic content decrease according to the proportion of the admixtures and curing tim
Pengaruh Perubahan Kadar Air pada Sifat-Sifat Tanah Organik yang Distabilisasi dengan Limbah Karbit dan Abu Ampas Tebu
Research on organic soil stabilization utilizing materials such as cement, lime, rice husk ash, fly ash, bagasse ash to change soil shear behavior has been widely carried out to this date. However, not many researchers have studied the changes in water content in organic soils that have been stabilized with such materials, especially on the changes in soil physical properties. This study aims to find out the effect of changes in water content in physical properties including: volume weight (γ), specific gravity (G), water content (w), void ratio (e), degree of acidity (pH) and content organic (O). A series of tests was conducted, namely the chemical composition of: organic soil test (TO), carbide waste (CCR), and bagasse ash (AAT), and testing for the physical properties of organic soil. Further, additional material (60% CCR and 40% AAT) was added to the soil in proportions: 5, 10, 15, 20, 25 and 30% combined with different initial water contents (498, 548 and 598%) and curing time: 7, 14, 21 and 36 days. Then, we conducted test for physical properties of the soil that has been stabilized. The physical and chemical properties of the soil change subject to added material content and ripening time. At high water content, the change is more significant than at lower water content. The volume weight, specific gravity, and acidity of the soil increases while the void ratio and soil organic content decrease. The optimal content of added material is 20% with an optimal time of curing 21 day