Enzymatically induced calcite precipitation (EICP) is a new breakthrough for liquefaction prevention. This approach uses urease enzyme directly instead of bacteria to hydrolyze urea that precipitated as calcite crystal by the availability of calcium ion. Cyclic triaxial shear test under undrained condition incorporated with bender element test were conducted conscientiously on the EICP-treated sands. The parameters study reviewed includes: size of the sand particle, confining pressure, calcite contents, and saturation degrees along curing. The effects of those factors on the shear modulus are systematically investigated and compared. It was revealed that the precipitated calcite wraps the sand particles, which supports simultaneously to the mechanical properties’ improvement. The sum of materials needed of urea and CaCl2 to reach a target of maximum shear modulus can be diminished prominently by reducing the saturation degree along curing. It is also revealed that the formation of the precipitated calcite is more significant than its amount on the strength improvement. The maximum shear modulus (Gmax ) of the sands treated with EICP increases with increasing in the calcite content, confining pressure, and decreasing in the saturation degrees during curing but the influence of the sands grain size is insignificant.

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ABSTRAKPantai Tinobu telah terjadi permasalahan seperti erosi pantai, erosi tersebut dapat terjadi secara alami atau karena adanya aktifitas manusia. Pantai Tinobu mengalami  endapan yang dapat mengakibatkan majunya garis pantai, pendangkalan muara sungai yang menyebabkan aliran sungai dapat memimbulkan banjir.Tujuan penelitian ini adalah mengetahui tinggi gelombang pada peramalan gelombang pantai Tinobu dengan mengkonversi data angin dan mengetahui bentuk penjalaran gelombang di pantai Tinobu dengan model simulasi CG WAVE pada SMS 10.0.10 di pantai Tinobu. Metode penelitian menggunakan analisis dan survey pasang surut,, topografi dan bathimetri.Hasil dari penelitian ini adalah tinggi gelombang dan periode gelombang signifikan maksimum di laut dalam dari arah timur adalah 0,81 meter dan 3,26 detik. Pada penelitian ini penjalaran gelombang yang disimulasikan adalah penjalaran pada arah Timur dengan sudut datang pada model isian 90 derajat. Kemudian dari arah datang angin ini saya mengambil periode 3,26 detik dengan menyamakannya pada kondisi peramalan gelombang pada hasil analisa perhitungan kala ulang periode dengan 25 tahun.   Kata Kunci : Gelombang, Water Modeling, Pantai.ABSTRACTTinobu Beach problems have occurred such as coastal erosion, erosion can occur naturally or due to human activities. Tinobu beach has deposited which can cause coastline advancement, silting of river mouths which causes river flow can cause flooding. The purpose of this study was to determine the wave height in the forecasting of Tinobu beach waves by converting wind data. and bathymetry. The results of this study are the wave height and the maximum significant wave period in the deep sea from the east is 0.81 meters and 3.26 seconds. In this study the wave propagation that I simulate is propagation in the East direction with the angle of incidence in the 90-degree field model . Then from the direction of this angina I took a period of 3.26 seconds by equating it to the wave forecasting conditions on the results of the analysis of the recalculation period with a period of 25 years. Keywords  : Waves, Water Modeling, Beaches

The need for raw water for various reasons, particularly clean water for households, public areas, and industry, will continue to rise as the world's population grows and the pace of growth in various fields accelerates. However, because the existing supply of clean water infrastructure is still limited, it has not been able to cover all of the country's water needs. Residents in Latambaga District, Kolaka Regency, are likewise concerned about the lack of safe water. Although the area has adequate water sources (river water) and a distribution network that distributes clean water to the population, the issue is getting water from these water sources to areas where there isn't an optimal clean water distribution network so that it can be used by the community population. As a result, it is required to assess PDAM Kolaka's clean water distribution network by employing the EPANET program application in its analysis. The findings of the pipeline network evaluation using the EPANET 2.0 application, the diameter of the pipes used in the evaluation, pipes with a diameter of 1" to 4", and the demand for 1,003 rods of PVC pipes

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