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"Manusia mempunyai hubungan yang erat dengan air sebagai salah satu kebutuhan utama. Salah satu peristiwa yang perlu mendapat perhatian lebih adalah adanya kontaminasi air tanah dan masih banyaknya air tanah yang digunakan sebagai sarana pemenuhan kebutuhan air. Skripsi ini bertujuan untuk merumuskan suatu protokol pemodelan fisik kontaminasi pencemar pada media berpori heterogen menggunakan seepage tank. Tujuan lain adalah untuk memperbaiki alat percobaan sehingga bisa digunakan untuk melakukan validasi dari pemodelan matematis yang ada. Pemodelan fisik ini meliputi aliran air tanah melewati media heterogen terdiskrit pada kondisi tunak dan juga transpor pencemar dengan mekanisme adveksi-dispersi yang terjadi akibat point-source loading.

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Humans have strong independence on water as one of their primary needs. One of the phenomena that should be focused more is the presence of groundwater contamination while at the same time groundwater is utilized as one of the main source of water supply. This undergraduate thesis aims to formulate a physical modeling protocol of contaminant transport through heterogeneous porous media by using seepage tank. Another additional purpose is to improve the function of the existing instrument so that it can be used to perform validation of various mathematical modeling. This physical modeling includes groundwater flow through heterogeneous discrete medium in steady-state conditions as well as contaminant transport in advection-dispersion mechanism that occurs as a result of point-source loading."

"Hubungan manusia dan sumberdaya air penting dan saling mempengaruhi satu sama lain. Salah satu peristiwa yang perlu mendapat perhatian adalah kontaminasi air tanah melalui dinding sungai. Makalah skripsi ini mengusulkan suatu protokol untuk memodelkan kejadian tersebut menggunakan seepage tank. Pemodelan ini meliputi aliran air melalui media berpori pada kondisi steady dan unsteady serta transpor pencemar mekanisme adveksi-dispersi yang terjadi akibat point-source loading. Meski demikian, terdapat kekurangan dalam analisa hasil pemodelan ini sehingga dibutuhkan pengembangan yang lebih lanjut.

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There is a reciprocal interaction between human and groundwater resources in which all components influence each other. Contamination occurred along soilwater interface in a river is an issue that has to be examined. Physical model of flow through porous media and contaminant transport using seepage tank is proposed to help the understanding of the phenomena. This model describes the flow of water through porous media in steady and unsteady condition and also transport of contaminant in advection-dispersion mechanism that happens for point-source loading. Yet, more development is needed to complete the analysis of this model?s output."

"Penelitian yang dilakukan oleh Wahyu Riyadi, Endang Mardiati dan Heru Winayadi pada tahun 1999 telah menghasilkan apparatus untuk memodelkan aliran air tanah terkekang. Apparatus ini berada pada tahap pengembangan dimana masih memerlukan berbagai penyempurnaan dari sisi alatnya maupun protokolnya. Penelitian ini mengusulkan suatu protokol untuk memodelkan aliran air tanah terkekang dan transpor pencemar pada media berpori heterogen dengan menggunakan alat buatan Wahyu Riyadi, Endang Mardiati dan Heru Winayadi. Pemodelan ini meliputi aliran air pada kondisi steady dan transpor pencemar berupa NaCl. Protokol yang diusung haruslah memberi hasil yang akurat dan presisi sehingga dilakukan repetisi percobaan dengan protokol yang sama, yang nantinya akan diamati penyimpangan data antar percobaannya. Hasil dari penelitian ini belum dapat dinyatakan sempurna karena hasil percobaan belum akurat dan presisi. Karena itu diperlukan beberapa penyempurnaan pada alat dan protokol.

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Research conducted by the Wahyu Riyadi, Endang Mardiati and Heru Winayadi in 1999 has produced apparatus for modeling unconfined groundwater flow. This apparatus is at development stage where they still require improvements in the in terms of the instrument and protocols. This research proposes a protocol for modeling unconfined groundwater flow and transport of contaminants in the heterogeneous porous media. This includes modeling of water flow in steady state and pollutant transport in the form of NaCl. Protocols carried must generate accurate and precise result, so experiment repetitions were done with the same protocol, and the deviations of data between experiments will be observed. The results of this research has not been stated as perfect because the result of the experiment is not yet accurate and precise. Therefore some improvements on the equipments and protocols are needed."

"Kebanyakan perencana struktur bangunan cenderung memodelkan struktur atas dengan menganggap pondasi sebagai sistem yang sangat kaku sehingga pada umumnya menghasilkan respon struktur yang lebih konservatif, sementara perencana pondasi memodelkan pondasi tanpa mempertimbangkan pengaruh dari struktur atas. Kenyataannya, struktur atas dan struktur bawah saling berinteraksi tergantung pada kekakuan dari kedua sistem struktur ini. Penelitian ini membahas tentang pengaruh jenis perletakan struktur bangunan yaitu perletakan jepit, sendi, dan fleksibel terhadap karakteristik dinamik struktur, respon seismik struktur serta berat tulangan yagn diperlukan oleh komponen utama struktur dengan bantuan software ETABS 9.7. Sistem struktur atas menggunakan sistem ganda yang merupakan kombinasi sistem dinding geser dan sistem struktur portal. Hasil penelitian menunjukkan bahwa dinding geser pada tingkat-tingkat bawah bangunan dengan perletakan jepit atau sendi menghasilkan gaya geser dan berat tulangan yang lebih besar (overdesign) dibandingkan terhadap bangunan dengan perletakan fleksibel, sebaliknya struktur portal pada tingkat-tingkat bawah bangunan akan menghasilkan gaya geser dan berat tulangan yang lebih kecil (underdesign).

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In modeling the upper structure, most of the building structure engineers tend to assume the foundationas a very rigid systemthat produces more conservative structural responses while in modeling the foundation, the foundation modeled without considering the effect of the upper structure. In fact, upper and lower structures are interacting depend on the stiffness of both the upper and lower structures system.

This research discusses the influence of the type of building structures supports namely fixed support, hinged support and flexible support to the dynamic characteristics of the structure, the seismic response of the structure and the weight of the reinforcement needed by the main structure`s components using ETABS 9.7.The upper structure use a dual system which is a combination of shearwall system and the frame system.

The results show that the shearwall at the lower levels of fixed support building or hinged support buildingprovide larger shear force and heavier reinforcement (overdesign)compared to the flexible support building. Otherwise, the frame structuresat lower levels of the building providesmaller shear force and lighter reinforcement (underdesign)."

"Sermo Reservoir has been useful for irrigation and power plant. Despite its good reservoir management the reservoir spills millions of cubic meter of water yearly. On the other hand, there is a need for domestic water for surrounding area that can not be met. It indicates that the reservoir capacity needs increasing. The combined spillway (Free flow spillway and siphon) has been studied where higher capacity of water storage may be attained without increasing the dam crest. This is conducted by increasing the crest of the open type spillway (for examole ogee) to a certain height and at the same time adding the capacity of the open type spillway with spion. At certain height above the open spillway crest, the siphon is priming to add the discharge out from the spillway and hence required height of flood water above the open spillway is reduced. Such method that is increasing spillway weir crest may be applied for Sermo Dam.The paper studie a typical reservoir called Waduk Sermo that is located in Kulon Progo, Special province of Jogjakarta, where the data is available for simulation. During three years of record, Sermo resevoir spills quite a lot of water which otherwise was very useful for the domestic water. With the increasing need for clean water, it is essential to study the real availability of water in the reservoir. Such spill would have been minimized when the dam was equipped with siphon spillway. Mathematical modeling of water balance in the reservoir during the three years of record was carried out. The out flow includes water for irrigation, electricity power and domestic purpose (drinking water). The domestic water discharge is varied in order to obtain optimal capacity for water withdrawal. The effect of higher spillway crest on the capacity of the reservoir to supply domestic water is simulated for comparison.The study shows that Sermo reservoir is capable of serving approximately 1501/s of domestic water with time of service is 92%. This is the same as if no water is available for approximately one month per year. An additional dam crest of 1 m high produces a capacity of approximately 2251/s at the same risk as before. There is approximately an additional 2 million m3 of water available for domestic water yearly. It is concluded that such reservoir might have been more optimal when the crest was 1 m higher."

"ABSTRAKPenelitian ini bertujuan untuk membuat mortar menggunakan sampah kertas yang telah diproses, untuk mendapatkan mortar yang ramah lingkungan, memenuhi standar dan diharapkan memiliki sifat mekanis yang lebih baik dibandingkan mortar yang menggunakan agregat alam dan tergolong beton ringan.Benda uji penelitian dibuat dengan persentase serbuk sampah kertas hasil pengolahan kertas bekas adalah10%, 15%, 20% dan 25% terhadap berat semen yang digunakan. Pengujian kuat tekan dan kuat lentur dilakukan pada hari ke-7,14, 21, 28,dan 56 sedangkan pengujian susut dilakukan hingga hari ke-28. Pengujian density pun dilakukan setelah umur mortar mencapai 28 hari.Dari hasil pengujian, didapatkan bahwa mortar dengan campuran 10% memiliki kuat tekanmutu sebesar 6.57 MPa dan 6.52 Mpa digolongkan kedalam tipe N yaitu jenis adukan dengan kuat tekan sedang, dipakai untuk aduk pasangan terbuka diatas tanah. Sedangkan campuran 15%memiliki mutu sebesar 4.62 MPa dan 25% sebesar 2.49 MPa digolongkan kedalam tipe O yaitu jenis adukan dengan kekuatan tekan yang agak rendah, dipakai untuk konstruksi tembok yang tidak menahan beban tekan tidak lebih dari 7 kg/cm² dan gangguan cuaca tidak berat.

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ABSTRACTThis research object is make mortar using office block waste paper with shred paper pretreatment to get green mortar, standardized, and has a better mechanical quality than mortar using natural aggregate. The shredding paper ratio in mixture are 10%, 15%, 20% and 25% to cement mass. Compressive strength and flexural test did at day 7th, 14th, 21st, 28th whereas shrinkage test did at day 28th. Density test also did after mortar at the age of 28 days.As aresult from test, providable that the mixed 10% and 15% of mortar has compressive strength 6.57 MPa and 6.52 MPa. This kind of product be classified to N type that is mixed with medium compressive strength, used for open paired stir up on ground. The mixture of 20% mortar has compressive strength 4.62 MPa and the mixture of 25% of mortar has compressive strength 2.49 MPa, it can be classified to O type that is kind of mixed with low compressive strength, use for wall construction with compressive strength less than 7 kg/cm2 and medium disturbance of weather"

"Sebuah perusahaan (PT.X) memiliki rencana jangka panjang untuk mengoptimalkan beberapa aset lahan dan bangunannya saat ini yang berada di kota-kota besar dengan tujuan asset lahan dan bangunan yang ada saat ini dapat menghasilkan sumber pendapatan bagi perusahaan.Optimalisasi difokuskan terhadap beberapa aset yang berlokasi di DKI Jakarta. Rencana yang akan dilakukan adalah dengan mengoptimalisasi aset lahan dan bangunan yang dimiliki dengan orientasi optimalisasi di bidang properti komersial seperti optimalisasi bangunan menjadi hotel, kantor sewa, dan ritel sewa. Namun pemilihan jenis alternatif optimalisasi tersebut ditentukan berdasarkan beberapa kriteria antara lain : 1. Aspek legalitas, 2. Aspek Teknis, 3. Aspek Lingkungan, 4. Aspek Bangunan/Tapak, 5. Aspek Pasar, 6. Aspek Keuangan sehingga dibutuhkan suatuan alias pemilihan terhadap optimalisasi yang sesuai dengan lokasi asset lahan dan bangunan. Metode Analytic Hierarchy Process (AHP) merupakan metode yang digunakan untuk pemilihan jenis optimalisasi aset berdasarkan aspek-aspek yang mempengaruhi optimalisasi suatu aset lahan dan bangunan.

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A company (PT.X) has a long term plan to optimize some of the land and buildings assets currently located in major cities with the goal of land and building assets that exist today can generate a source of revenue for the company. Optimization is focused on several assets located in Jakarta. The planning is to optimize land and building assets that owned with optimizing orientation in the field of commercial property such as the optimization of the building into a hotel, rental office, and rental retail spaces.

However, the choice of optimization alternatives is determined based on several criteria, such:

1.Legality Aspect,

2. Technical Aspect,

3. Environmental Aspect,

4. Aspect of Building / Site,

5. Aspect of Market,

6. Financial Aspect, that required an analysis of the selection optimization according to the location of the land and building assets.

Analytic Hierarchy Process (AHP) is a method that used for selecting the type of asset optimization based on the aspects that influence the optimization of a land and building assets."

"In the construction world, concrete is still the main choice because of good economic value, as well as a variety of advantages. As one of the primary material in the construction world, concrete has always been developed in order to achieve improvement. Nearly all the material used for the manufacture of concrete using materials from nature so that with the use of concrete, the many large-scale mining occurred on natural rocks as concrete forming materials. This causes the least capacity provided by nature. Based on the results of an experimental study, recycled aggregate mortar containing 25% to 45% for coarse aggregate, and 70% to 100% for fine aggregate. From the explanation of it, arising out of research on the use of recycled aggregates instead of natural aggregate in concrete production. In this study, the waste concrete is concrete that is used with the K300-K350 quality crushed into aggregate recycling. The study was conducted on compressive strength, flexural strength, and shrinkage of the concrete. Compressive strength is reviewed at the age of 7 to 56 days, whereas for flexural strength at 28 and 56 days. For the composition of recycled aggregate is set at 0%, 20%, 40%, and 60%. Results of the testing showed that concrete with recycled coarse aggregate 20% has the highest compressive strength value, which is an increase of 22.67% from the normal concrete compressive strength at 28 days. The results of flexural strength testing, concrete with recycled coarse aggregate composition of 20% and 40% had the highest flexural strength values, ie an increase of 2.1807% of the flexural strength of normal concrete at 28 days. For shrinkage testing, concrete with recycled coarse aggregate content of 60% has the highest shrinkage rate when compared with the composition of the mixture of other aggregate.

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Dalam dunia konstruksi, beton masih menjadi pilihan utama karena nilai ekonomisnya yang baik, serta berbagai keuntungan. Sebagai salah satu material utama dalam dunia konstruksi, beton selalu dikembangkan demi mencapai peningkatan. Hampir semua material yang digunakan untuk pembuatan beton menggunakan material dari alam sehingga dengan penggunaan beton yang banyak maka terjadi penambangan besar-besaran terhadap batuan alam sebagai bahan pembentuk beton. Hal ini menyebabkan semakin sedikitnya kapasitas yang disediakan oleh alam. Berdasarkan hasil studi eksperimental, agregat daur ulang mengandung mortar sebesar 25% hingga 45% untuk agregat kasar, dan 70% hingga 100% untuk agregat halus. Dari penjabaran itu, timbul penelitian mengenai penggunaan agregat daur ulang sebagai pengganti agregat alam pada pembuatan beton. Dalam penelitian ini, limbah beton yang digunakan adalah beton dengan mutu K300-K350 yang dihancurkan menjadi agregat daur ulang. Penelitian dilakukan pada kuat tekan, kuat lentur, dan susut pada beton. Kuat tekan ditinjau pada umur 7 hingga 56 hari, sedangkan untuk kuat lentur pada 28 dan 56 hari. Untuk komposisi agregat daur ulang ditetapkan sebesar 0%, 20%, 40%, dan 60%. Hasil dari pengujian didapatkan bahwa beton dengan agregat kasar daur ulang 20% mempunyai nilai kuat tekan tertinggi, yaitu meningkat sebesar 22,67% dari kuat tekan beton normal pada umur 28 hari. Hasil pengujian kuat lentur, beton dengan komposisi agregat kasar daur ulang 20% dan 40% memiliki nilai kuat lentur tertinggi, yaitu meningkat sebesar 2,1807% dari kuat lentur beton normal pada umur 28 hari. Untuk pengujian susut, beton dengan kandungan agregat kasar daur ulang 60% memiliki nilai susut tertinggi apabila dibandingkan dengan komposisi campuran agregat lainnya."

"ABSTRAKWater loss in a channel is an important component of the hydrologic budget for the design and planning of a water diversion and delivery system. Quantitative assessment of channel losses is required in the calculations of flow components of a river basin or reach and the projections of design flows at the withdrawal and delivery points of the water diversion system. In this study, hydrologic methods are employed to determine water losses along the Sheyenne River, a proposed diversion project. The hydrologic budget approach is considered the most appropriate method for the Sheyenne River and the proposed project. Long-term, monthly average, and annual channel losses and their longitudinal distributions are obtained. The estimated losses can be used as the additional discharge, compensating for the losses in the water delivery and supply system."

"Perkuatan geosintetik sering kali digunakan dalam pekerjaan penimbunan untuk mengantisipasi differential settlement yang terjadi apabila dibangun pada tanah lunak. Adanya perkuatan geosintetik ini diyakini dapat memberikan hasil yang cukup baik untuk meningkatkan performa timbunan agar tidak mengalami penurunan yang tidak seragam. Studi ini dilakukan dengan memvariasikan nilai kohesi tanah lunak, indeks kompresi tanah lunak, ketebalan tanah lunak, serta banyaknya lapisan geosintetik yang digunakan. Bahasan penelitian ini mencakup besarnya penurunan pada tanah timbunan pada akhir konsolidasi primer, regangan dan gaya aksial pada geosintetik yang disimulasikan menggunakan program Plaxis 2D. Selain itu, pengaruh terhadap faktor keamanan juga ditinjau pada akhir konstruksi dan juga pada saat konsolidasi primer selesai, agar diketahui bagaimana kelongsoran yang terjadi dan kemungkinan kegagalan timbunan.

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Geosynthetic reinforcement is usually used in embankment construction to anticipate the differential settlement that occurs when it’s constructed on the soft soil. The use of geosynthetic reinforcement is believed could give a pretty good result to enhance the performance of the embankment so that the differential settlement would not occur. This study is done by varying the value of cohesions, compression indexes, and the thickness of soft soil layer, and also the number of geosynthetic layers used. The discussion of this research concludes the value of displacement of the embankment at the end of primary consolidation, the strain and the axial force of geosynthetic layer which is simulated by using Plaxis 2D. And also, the effects occured to safety factor is reviewed at the end of construction and at the end of primary consolidation, so that we know how the failure could occur and the chance of failure of the embankment."