STABILISASI TANAH LEMPUNG DENGAN PENAMBAHAN SERABUT KELAPA PADA PENGUJIAN KUAT GESER LANGSUNG (DIRECT SHEAR TEST)

Clay is ground that has some properties bad that can interfere with the strength of a building construction so that the construction that can experience damage physically are not able to be predicted. Bad Character by soil clay are relatively large, high plasticity, and strong low shear value. With the development of soil mechanics, various soil improvement methods can be used to solve this situation. An alternative that can be used as a soil stabilizer is coconut fiber. Selection of coconut fibers as mixed material because coconut fibers can add strong sliding soil, material that is easy to pass water. The purpose of this study is to determine the effect of adding coconut fiber on the value of clay stabilizers.. The research method used is field survey and sempel retrieval method is with laboratory analysis approach, where strong shear testing is carried out three times with variations of coconut fiber as much as 0.5%, 1% and 1.5% with coconut fiber length of 3 cm and 5 cm. From the test results the largest increase in the addition of coconut fiber with a percentage of 1.5% of the length of coconut fibers 3 cm and 5 cm in clay increased the angle of shear of the soil (ø) by 170 and 280, cohesion (c) of 0.2387 kg/cm2 and 0.2383 kg/cm2, shear strength (τ) of 0.281 kg/cm2 and 0.312 kg/cm2, or it can be said that the addition of 1.5% coconut fiber will increase the strong value of shear by 47.3% and 63.46%.

PENGARUH KADAR AIR TERHADAP BESARNYA PENURUNAN PADA UJI KONSOLIDASI

Clay soil is a cohesive soil with low bearing capacity and low shear strength where the load on it will be limited. The addition of water content in clay soil will result in changes in soil volume that will affect the strength of the soil. The research aims to know how much water content affects the values of consolidation settlement. A consolidation test was carried out three times with variations of the original soil sample, 35% water content and 30% water content. The results obtained a settlement of 0,1864 cm for original water content, 0,1677 cm for 35% water content, and 0,1414 cm for 30% water content.

UTILIZATION SPENT BLEACHING EARTH AS A FILLER OF MATERIAL CONSTRUCTION

Spent bleaching earth (SBE) is a waste from cooking oil industry. It is categorized as one of the hazardous and toxic materials, because oil residues in it. Generally, SBE is overcome by landfill and it’s sometimes become problems. Basically SBE contains SiO2 and the size of the grain is very fine, almost the same as the fine aggregate of sand used for making brick. In this study, the making of brick used SBE with several variations (2.75% - 27.52%) of the total raw materials used. Brick making methods are based on SNI 03-0348-1989 for raw material ratio, SNI 03-0348-1989 for molding and presshing, SNI 03-6825-2002 for drying and curing. The brick quality was determined based on fineness modulus parameters, dry weight, brick absorption to water and compressive strength. Brick contain SBE 2.75% was produced with molding size of 15cm x 30cm x 9cm, it has an average dry weight of 7.80 kg, compressive strength of 8.95 MPa and absorbing power of 1.26%.

ANALISIS NILAI KEPADATAN LAPANGAN DENGAN SAND CONE TEST (STUDI KASUS: JALAN YOS SUDARSO KOTA PALANGKA RAYA)

Soil compaction is required so that the embankment is strong and balanced with structural and non-structural loads. One of the efforts to handle soil with low bearing capacity is to change the subgrade using soil that is considered good. Therefore, an attempt was made to estimate the density of the soil in the field by conducting a sand cone test on the selected embankment material on the Yos Sudarso road work, Palangka Raya City. The sample used in this study came from Hampangen Village, Kasongan Baru Village, Katingan Hilir District, Katingan Regency, Central Kalimantan Province. The results of tests carried out on laboratory density testing and sand cone testing on Yos Sudarso Street, Palangka Raya City can be ascertained that the density obtained from dry soil density γdry = 1.29 g/cm3, maximum dry density γd lab = 1.35 g/cm3 γdr / γd lab x100 = Dr. So the approved density is Dr = 95.86%.

STUDI KELAYAKAN PEMBANGKIT LISTRIK TENAGA SURYA UNTUK PENERANGAN DI LOKASI WISATA PANTAI GEMAH TULUNGAGUNG JAWA TIMUR

The condition of electric energy at Gemah beach on the south coast of Tulungagung has not been fully supplied by PLN, so it is necessary to take advantage of renewable energy. This study aims to calculate the need for electrical energy at Gemah beach and calculate the number of solar panels and the required generating capacity. From the calculation results obtained: Total load energy per day 17392 Wh, Total load Ah requirement per day = 362 Ah, and need battery with capacity = 1358 Ah, capacity of selected battery in Amp-hour is 800 Ah, batteries in parallel is 2, Number of batteries in series = 24, Total number of batteries = 48, capacity of total battery is 1600 Ah, Total kilowatt-hour capacity of battery = 76.8 kWh. Meanwhile, for the purposes of generation required: The number of solar modules to meet the load requirements = 28 modules. Generating capacity = 5.6 kWp, rounded off to 6 kWp

EVALUASI KEEKONOMIAN KERJA ULANG PINDAH LAPISAN DENGAN METODE PERFORASI SUMUR PRODUKSI

The problem is that there is no certainty about the production capacity of the wells before evaluating the performance of production wells. The research objective was to describe the condition of oil and gas reserves in production wells and an economic picture of the MBR production resources after the recovery period by moving layers using the perforation method. This study used a used research method with a case study approach, namely the case that occurred in the MBR production well of PT. Medco E&P Tarakan operation area. The results of the evaluation of production capacity after displacement recovery based on the analysis of logging data at a depth of 850 MZ, it is known that the initial oil reserves (OOIP) are 284,304 STB with a recovery factor of 25%. The results of the calculation of the economic indicator for the proposed perforation of work to move layers, the total value of NPV. 15% was obtained in the eighth month in total lifting of 28,466, namely USD 123.561, the payout time for this work was 1.8 months with an IRR of 340% indicating that investment has the potential to provide benefits.

PENGARUH JUMLAH DAN SUDUT PEMASANGAN SUDU TERHADAP DAYA TURBIN SAVONIUS

The problem in Energy conservation is finding new opportunities for high-efficiency energy generation including wind power generating machines. Aims of this study to determine the effects of blade number and curv angle of blade mounting on the output power of a Savonius type wind turbine. This low speed wind turbine is intended to get energy at the top of a multi-storey building in an urban area. Tests were carried out on a laboratory scale, using savonius wind turbines with 400 mm diameter and 500 mm height. The driving wind speed of the turbine is set between 1.5 to 8.5 m / s. While the number of blades used is 2 types, namely rotor with three blades and rotor with 4 blades, each of which is tested on 3 different types of curv angle blade. The investigation results are expected to show that the wind tubing from each experiment will give different characteristics. This investigation results that there was increasing in efficiency in the savonius turbine with blades. The highest rotation and power occur when the turbine uses 2 blades and -50 curv angle of blade mounting

ANALISIS LAPISAN CETAK PRINTER 3D SPESIMEN PLASTIK PLA KELIPATAN 0,05 mm TERHADAP ENERGI PUKUL

Tidak diketahuinya energi pukul (EP) hasil uji pukul dalam pembuatan spesimen plastik dengan printer 3D berbagai tebal per lapisan menjadi masalah yang dihadapi. Tujuan analisis untuk memperoleh EP spesimen plastik yang linier atau tidak. Metoda analisis meliputi: desain bentuk dan ukuran spesimen plastik, pencetakan spesimen dengan printer 3D dari filamen plastik jenis PLA diameter 1,75 mm dimulai dari tebal lapisan 0,1 mm hingga 0,5 mm dengan kelipatan lapisan 0,05 mm dan dibuat fulfill (tidak berongga) pada temperatur 200℃, uji pukul charpy, perhitungan EP, dan analisis hasil. Hasil analisis uji pukul dari spesimen tebal layer 0,1-0,35, EP naik dan spesimen tebal lapisan 0,4-0,5 EP mulai turun dan nilainya sama. Puncak EP yang dihasilkan berada pada tebal lapisan 0,35 mm dengan EP senilai 1,264 J dan energi pukul spesifik (EPS) atau harga impact (HI) senilai 0,01261 J/mm2 dan di posisi kedua pada tebal lapisan 0,3 mm dengan EP senilai 1,215 J dan EPS senilai 0,01212 J/mm2 yang menunjukkan bahwa hasilnya tidak linier atau semakin tebal lapisan tidak selalu kekuatannya semakin besar dan spesimennya semakin kuat dan paling kuat berada di tebal lapisan 0,35 mm. Hasil visual spesimen uji pukul dari plastik dengan printer 3D semakin kecil lapisan yang digunakan semakin halus dan memiliki estetika yang bagus.

ANALISA UNJUK KERJA INDUCED DRAFT FAN PLTU ASAM-ASAM UNIT 3 DAN 4

Throughout the year 2015, PLTU Asam Asam Unit 3 and 4’s Induced draft fans frequently having issues. These issues were affects customer’s elecricity consumption because of load generated from PLTU Asam Asam unit 3 and 4 is was decreased heavily, seldom made the unit shut down for maintenance. This issues was being discussed and investigated to find the source and solutian to fix it. After the investigation, it is found that fly ash who was being carried by flue gas through IDF was stuck to fan’s blade and create unbalance in its rotation. Next modification was applied to fly ash transmitter to make sure its operating continous because it has been stopped for a while. The effect of this modification is quite significant if we compare data from before and after modification, it can be see that derating and shutdown because of IDF problem is fewer than what it was before modification.