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Abstrak :
ABSTRAK
Rockfill dams have better stability than homogeneous soil dams. It allows to design the dam more slim with a higher slope. The disadvantage of rockfill dam is in the core zone as an impermeable zone. Zoned vertical core rockfill dam is a combination of various material properties. Geometry and drainage design will affect the seepage and phreatic line properties that occur. Numerical modeling and calculations are used to calculate the seepage profile more accurately. The combination of the parameters of the permeability coefficient (K), reservoir water level (Δh) and the length of the seepage path (L) can be used to determine the relationship between parameters with the same unit. 2D modeling take into account saturated/unsaturated conditions with steady state on each parameter. This study uses the Jatibarang-Indonesia dam as a basic model. The seepage profile at condition K1 (k = 1x10-5cm/sec) is q/k = -0.0018 (h2/L)2 + 1.3496h2/L + 53.241 and the seepage profile K2 (k=1x10-7cm/s) is q/k = -0.1521 (h2/L)2 + 90.402h2/L + 5480.2. This equations can be used to estimate seepage that occurs in a dam of other rock fill zoned vertical core dam based on the permeability coefficient value (K) more practically for all values of Δh and L reviewed.

Abstrak :
ABSTRAK
The purpose of this research is to study and compare the stabilities of soft clay embankments for flooding protection using soil compaction and soil lining techniques in construction. There are five types of soft clay embankments with three-meter height used in this research. The width at the top of the embankment is one meter and the vertical to horizontal ratio of slope of embankment on the water side equals 1:1. The soil compaction technique was used to construct the embankment types 1, 2 and 3 and the value of coefficient of permeability of clay in embankment to be 1x10-5 cm./sec was given. The vertical to horizontal ratio of slope of embankments on the dry side equal 1:1, 1:1.5 and 1:2, respectively. The soil lining was used to construct the embankment types 4 and 5 and the vertical to horizontal ratio of slope of embankments on the dry side equals 1:1, without compaction techniques. Lining material with 0.10 meter thickness was placed on the water side surface of the embankment. The coefficient of permeability of lining material used in embankment types 4 and 5 equals 1x10-5 cm/sec. and 1x10-6 cm./sec., respectively. The research process consisted of using parameters obtained from shear strength test and water flow test through soft clay embankment simulated in laboratory to analyze water flow and slope stability analysis of the embankment. In addition, the area and budget for construction of embankment, not including the soil compaction and soil lining cost, were used to select the suitable type of soft clay embankment. The results showed that the soft clay embankment type 5, using soil lining on the water side surface of the embankment, was the most suitable embankment. Also, the level of stability of the soft clay embankment type 5 had the highest value with the need to use area and budget for construction less than embankment types 1, 2 and 3.

Abstrak :
Pemodelan fisik penjalaran pencemar menggunakan seepage tank yang sudah dilakukan oleh Herlambang (2012) dan Triandhika (2013) sudah bisa memvisualisasikan adveksi dari penjalaran pencemar namun belum bisa memvisualisasikan fenomena adveksi dan dispersi yang mengalami refaksi. Tujuan penelitian ini adalah untuk mengembangkan protokol alat seepage tank untuk mampu memvisualisasikan penjalaran pencemar pada perched aquifer. Media berpori yang digunakan adalah pasir dengan dua jenis yang berbeda nilai konduktivitas hidroliknya. Pasir dialiri air hingga jenuh dan dibiarkan dalam kondisi pengaliran steady lalu pencemar dialirkan ke lapisan pasir dan dilihat visualisasi penjalarannya. Hasil dari penelitian ini berupa protokol yang merupakan pengembangan protokol sebelumnya. Pengembangan dari protokol sebelumnya adalah (1) penetapan kondisi batas kedap air pada bagian tepi kiri dan kanan kolom pasir di dalam seepage tank, (2) pengaturan debit inflow menjadi sekecil mungkin sehingga permukaan pasir tidak tergerus, (3) penggunaan jarum infus sebagai pengganti injektor, dan (4) pengaturan debit aliran pencemar sebesar 0,005 mL/detik. ...... Previously, Herlambang (2012) dan Triandhika (2013) were able to visualize contaminant advection with physical modeling using seepage tank However contaminant transport through heterogeneous systems, according to Freeze and Cherry (1979), they refract as passes from one medium to another with different values of hydraulic conductivity. The purpose of this study was to develop a protocol for the seepage tank and to visualize contaminant transport flow through perched aquifer. Porous media in seepage tank consist of sand with two different types of hydraulic conductivity values. Sand was saturated and the flow was in steady conditions, thencontaminantwas discharged into sand layers. Visualization of contaminnant advection and dispersion is recorded and analized. Result of this research is a protocol that is an improvement from the previous protocol; (1) setting impermeable condition on left and right of sandbox inside seepage tank, (2) controlling pump inflow as low as possible to prevent scouring on top of sandbox, (3) replacing injector into infuse needle, and (4) setting contaminant loading 0,005 mL/s.

Abstrak :
Pencemaran air tanah yang terus meningkat pada masa kini dengan berbagai risikonya, mendesak perlunya pencegahan dan pengendalian terhadap sumber pencemar salah satunya dengan mempelajari mekanisme penjalarannya. Diperlukan pemahaman rembesan dan penjalaran pencemar di dalam sistem air tanah melalui pemodelan matematis, pemodelan fisik di lab dan pemodelan fisik di lapangan. Ketiga pemodelan tersebut memiliki kekurangan yang dapat dipenuhi pemodelan lainnya. Seperti dibutuhkannya pemodelan fisik di lab untuk menyimpulkan bahwa suatu model matematis dapat divalidasi. Sementara tiap pemodelan memerlukan suatu protokol untuk mendapatkan hasil yang didapatkan dapat diulangi. Skripsi ini bertujuan untuk mengembangkan suatu protokol pemodelan fisik pengamatan penjalaran pencemar pada akuifer berlapis. Pada percobaan ini menggunakan variasi tiga lapisan yang diharapkan dapat jelas teramati perbedaan aliran air tanah pada lapisan yang berbeda, dimana nantinya akan terjadi refraksi. Selanjutnya untuk diamati dan dianalisa proses aliran air dan pencemaran pada aliran air tanah. ......Increasing of ground water pollutant urge to prevent and control it's resource, one of them is by studying it?s spreading mechanism. Understanding of infiltration and spreading at ground water should be done by using mathematic model and also physical model at laboratory and site. All of them have disadvantages which might fulfilled by another model. Such as physical model at laboratory is needed to validate mathematic model. Meanwhile, a protocol is needed to obtain repeatable result in modelling process. This research has a purpose to develop a protocol of physical model of pollutant spreading observation in stratified aquifer. Using three layers as a varian is assumed that the difference of flow at ground water can be observed clearly, which is called refraction. Then, the process of flow and pollutant spreading at ground water will be observed and analyzed.

Abstrak :
This book presents recent research into developing and applying computational tools to estimate the performance and safety of hydraulic structures from the planning and construction stage to the service period. Based on the results of a close collaboration between the author and his colleagues, friends, students and field engineers, it shows how to achieve a good correlation between numerical computation and the actual in situ behavior of hydraulic structures. The book’s heuristic and visualized style disseminates the philosophy and road map as well as the findings of the research. The chapters reflect the various aspects of the three typical and practical methods (the finite element method, the block element method, the composite element method) that the author has been working on and made essential contributions to since the 1980s. This book is an advanced continuation of Hydraulic Structures by the same author, published by Springer in 2015.