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PENGEMBANGAN PERANGKAT LUNAK MODEL HUJAN-ALIRAN METODE GIUH Jayadi, Rachmad; Aminullah, Akhmad; Triyoso, Christopher
Jurnal Ilmiah Desain & Konstruksi Vol 19, No 1 (2020)
Publisher : Universitas Gunadarma

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.35760/dk.2020.v19i1.3495

Abstract

Untuk mengatasi kesulitan dalam perkiraan hidrograf banjir pada DAS tak terukur di DTA Waduk Wonogiri, dilakukan penelitian awal penggunaan hidrograf satuan metode GIUH. Evaluasi ketelitian metode ini menggunakan acuan hidrograf satuan terukur pada empat DAS yang dihitung menggunakan metode Collins, dengan mencermati debit puncak, waktu puncak, dan waktu dasar. Hasil penurunan hidrograf satuan GIUH digunakan untuk hitungan hidrograf banjir menggunakan program aplikasi model hujan-aliran yang dibuat menggunakan compiler Visual Studio. Hasil penelitian menunjukkan bahwa program aplikasi dapat digunakan untuk hitungan hidrograf banjir secara cepat dengan memanfaatkan sistem telemetri data hidrologi real time dan online. Debit puncak hidrograf banjir metode GIUH cenderung underestimated, yaitu antara -9,3% sampai dengan -54,9%. Untuk waktu puncak dan waktu dasar tidak ditemukan pola perbedaan yang spesifik, yaitu antara 11,1% sampai dengan +66,7% dan -6,7% sampai dengan +46,15%. Penelitian lebih lanjut perlu dilakukan dengan mengkaji lebih detil faktor orde sungai tertinggi dan rumus empirik dynamic parameter velocity agar diperoleh hidrograf satuan yang lebih akurat.
DEVELOPMENT OF X-BAND RADAR DATA-BASED SNAKELINE FOR PREDICTING SEDIMENT DISASTER Henggar Risa Destania; Istiarto Istiarto; Rachmad Jayadi
Simposium II UNIID 2017 Vol 2 (2017)
Publisher : Simposium II UNIID 2017

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (900.549 KB)

Abstract

Sediment-related disaster are terrible disaster that can catastrophically impact to facilities and people must to keep in mind to make sediment-related disaster information that can be predicted from rainfall and response of drainage area by using snakeline. This research produce the important indices on precipitation related to debris and shows current status of the stage of response of drainage area against rainfall by using a couple of short and long term indices. It shows the water storage volume in soil layer with calculation of soil water index (SWI) by using X-band MP (Multi Parameter) rainfall radar data that has been installed at the top of Merapi Mountain (Merapi Museum). The snakeline can be used as monitoring and observation tools of SWI changes in response to rainfall intensity in Boyong river (BO-D5) and works as a database for the next research in identifying criteria for warning. Although there was no record of sediment disaster occurrence, at least from the result of snakeline it was confirmed that from June 2016 – June 2017 with 80.28 mm SWI maximum values has not yet become the maximum limit of SWI value for lahar occurrence in Boyong drainage area (BO-D5).
Penilaian Kinerja Pengelolaan Daerah Aliran Sungai Berbasis Model Hidrologi Elementer Kasus: Daerah Tangkapan Air Waduk Mrica Lukman Hidayat; Sahid Susanto; Putu Sudira; Rachmad Jayadi
agriTECH Vol 34, No 3 (2014)
Publisher : Faculty of Agricultural Technology, Universitas Gadjah Mada, Yogyakarta, Indonesia

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (478.683 KB) | DOI: 10.22146/agritech.9463

Abstract

Land conversionfromforest tocultivation ofvegetablecropsthat did notfollow the rules ofconservation practices, increased therate ofsedimententeringthe reservoirof Mrica. The reservoir which have been operated since 1989, will be full of sediment in 2021. Complexity of managing watershed areas still require an innovative approach to improve the hydrological situation, particularly to conserve water resources. The phenomenon of land use change and performance impacts caused, an event in nature that are necessary to determine the action that needs to be done in the future. Hydrologica lmodels is an extrapolation tool that can help understanding the phenomenon. This study aims at optimizing the performance-related watershed management, using a quantitative approach based on elementery hydrological models. This paper, using the method of literature review, was focused on revealing conception, as the approach in achieving the goal. The conception ofthe study wasthe assembly-serialsequence of hydrological models and watershed management-related quantitative assessment performance. The concept of the assembly will apply the role of hydrological models as a basis for quantitative assessment of performance-related watershed. The results of assembly, will provide an overview of the role of hydrological models, to produce information relating to the performance of output-based watershed management. Information obtained from such a role can be used as an alternative input in policy of water resources management and the basis for the development of specifi c hydrological models for Mrica reservoirs.ABSTRAK Alih fungsi lahan  dari hutan menjadi lahan budidaya tanaman sayuran yang belum sepenuhnya mengikuti kaidah konservasi semakin menambah laju sedimentasi yang masuk ke waduk Mrica. Waduk yang mulai beroperasi tahun 1989, akan dipenuhi sedimenpada tahun 2021. Kompleksitas pengelolaan kawasan DAS masih membutuhkan suatu inovasi pendekatan hidrologi untuk memperbaiki situasi,terutama untuk melestarikan sumberdaya air. Fenomena perubahan dan alih fungsi lahan dan dampak kinerja yang ditimbulkan,  merupakan kejadian di alam yang perlu dipahami untuk menentukan tindakan yang perlu dilakukan di waktu yang akan datang. Model hidrologi dipandang sebagai alat ekstrapolasi yang dapat membantu memahami fenomena tersebut. Penelitian ini bertujuan untuk mengoptimalkan pengelolaan DAS, menggunakan pendekatan kuantitatif berbasis model hidrologi elementer. Tulisan ini, menggunakan metode kajian pustaka,difokuskan untuk mengungkapkan konsepsi penelitian,sebagai metode pendekatan dalam mencapai tujuan. Konsepsi penelitian yang dimaksud yaitu perakitan-rangkaian serial model hidrologi dan penilaian kuantitatif pengelolaan DAS terkait kinerjanya. Dalam konsep perakitan tersebut akan diaplikasikan model hidrologi sebagai basis penilaian kuantitatif  kinerja DAS. Hasil perakitan akan memberikan gambaran peran model hidrologi dalam menghasilkan informasi yang berkaitan dengan kinerja pengelolaan DAS berbasis output. Informasi tersebut dapat digunakan sebagai alternatif masukan dalam  kebijakan pengelolaan DAS-Sumberdaya air dan menjadi dasar pengembangan model hidrologi spesifi k daerah tangkapan air waduk Mrica.
Prediksi Debit Sungai Bedog dan Gajahwong Dengan Model Arima sebagai Dasar Penentuan Pola Tanam Murtiningrum Murtiningrum; Sudjarwadi Sudjarwadi; Rachmad Jayadi; Putu Sudira
agriTECH Vol 36, No 4 (2016)
Publisher : Faculty of Agricultural Technology, Universitas Gadjah Mada, Yogyakarta, Indonesia

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (721.032 KB) | DOI: 10.22146/agritech.10518

Abstract

Planting pattern in an irrigation system is affected by water availability in river which may fluctuate from time to time. The objective of this paper is to assess the discharge fluctuation characteristic of Bedog and Gajahwong Rivers measured respectively in Cokrobedog and Mrican Weirs. The historical discharge data of the two rivers was assessed to predict river discharges of subsequent year as a basis of planting pattern determination. The ARIMA model was employed to predict water avalability. Model test showed that ARIMA (1,1,0) and ARIMA (2,1,0) could accurately predict river discharge of the two rivers. Considering parsimony principle, the ARIMA (1,1,0) model was chosen as the most suitable model. Based on predicted discharge, the previous planting pattern can still be applied in the future.ABSTRAKPola tanam pada sistemirigasi dipengaruhi oleh ketersediaan air di sungai yang bervariasi dari waktu ke waktu. Tujuan penelitian ini adalah untuk menganalisis karakteristik fluktuasi debit Sungai Bedog dan Sungai Gajahwong yang masing-masing diukur di Bendung Cokrobedog dan Bendung Mrican. Data historis debit kedua sungai dianalisis untuk menentukan karakteristik dan memprediksi debit pada tahun berikutnya sebagai dasar penyusunan pola tanam. Model ARIMA dipergunakan untuk memprediksi ketersediaan air. Uji model menunjukkan bahwa ARIMA (1,1,0) and ARIMA (2,1,0) mampu memperkirakan debit kedua sungai. Dengan mempertimbangkan prinsip parsimony, maka model ARIMA (1,1,0) dipilih sebagai model yang paling sesuai. Berdadsarkan prediksi debit, pola tanam sebelumnya yaitu padi-padi-palawija masih dapat diberlakukan di masa yang akan datang. 
Validasi Model Hidrologi SWAT di Daerah Tangkapan Air Waduk Mrica Lukman Hidayat; Putu Sudira; Sahid Susanto; Rachmad Jayadi
agriTECH Vol 36, No 4 (2016)
Publisher : Faculty of Agricultural Technology, Universitas Gadjah Mada, Yogyakarta, Indonesia

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (960.715 KB) | DOI: 10.22146/agritech.16772

Abstract

Land cover index production has exceeded 80 % of the total area of  the upstream catchment area of Mrica reservoirs, indicating the occurrence of land conversion. Elementary hydrological model, is predicted as an extrapolation tool that can help to understand the complexity of watershed management, including land conversion. Soil Water Assessment Tool (SWAT) is a physically based, deterministic, continuous, watershed-scale hydrologic models that was developed by the USDA Agricultural Research Service. SWAT was developed from numerous individual models within a period more than 30 years, and has been applied in several areas. The aim of this study was applying the SWAT on the upstream region of Mrica reservoirs. The method of the research was using the SWAT modeling procedure through a systems based on input output processes (IO). Output model was in the form of flow rate, validated by means of calibration and verification using statistical and graphical criteria on monthly scale. The results showed that their value of R2 = 0.61, NSE = 0.61, PBIAS = -0.61 % and MB = -0.25 for calibration, and R2 = 0.74, NSE = 0.73, PBIAS = -4.06 % and MB = -1.57for verification. The value of the statistical test showed that the model SWAT has good degree of precision and accuracy in watershed modeling. NSE values > 0.65 indicates that the SWAT model has an accuracy of very good degree. Several challenges in this watershed modelling are the availability and adequacy of data, the optimizationof parameters, time and computer resources. ABSTRAKIndeks Penutupan Lahan (IPL) produksi yang telah melebihi 80 % dari total luas kawasan Hulu Daerah Tangkapan Air (DTA) waduk Mrica, mengindikasikan telah terjadinya alih fungsi lahan. Model hidrologi elementer, dipandang sebagai alat ekstrapolasi yang dapat membantu untuk memahami kompleksitas pengelolaan kawasan Daerah Aliran Sungai (DAS), di antaranya alih fungsi lahan. Soil Water Assessment Tool (SWAT) adalah model hidrologi skala DAS berbasis fisik, deterministik, dan kontinyu yang dikembangkan oleh USDA (United States of Department of Agriculture) Agricultural Research Service. Model SWAT dikembangkan dari sejumlah model-model individu dalam periode lebih dari 30 tahun, dan telah diaplikasikan pada beragam wilayah, dalam rentang waktu yang cukup lebar. Penelitian ini bertujuan untuk mengaplikasikan model SWAT pada kawasan hulu DTA waduk Mrica. Metode yang digunakan yaitu menjalankan prosedur pemodelan SWAT melalui pendekatan sistem yaitu proses Input Output (IO). Luaran model berupa debit aliran, yang kemudian divalidasi dengan cara kalibrasi dan verifikasi menggunakan kriteria statistik dan grafis pada skala bulanan. Hasilnya menunjukkan bahwa nilai R2 = 0,61, NSE = 0,61, PBIAS = -0,61 % dan MB = -0,25 untuk kalibrasi, dan R2 = 0,74, NSE = 0,73, PBIAS = -4,6 % dan MB = -1,57 untuk verifikasi. Nilai uji statistik tersebut menunjukkan bahwa model SWAT mempunyai tingkat presisi dan akurasi yang baik dalam pemodelan DAS. Nilai NSE > 0,65 mengindikasikan bahwa model SWAT yang diaplikasikan mempunyai tingkat akurasi mencapai derajat sangat baik. Tantangan yang dihadapi dalam pemodelan DAS ini yaitu ketersediaan dan kecukupan data, optimasi parameter, waktu dan sumberdaya komputer.
Analisis Pengaruh Karakteristik Hujan terhadap Gerakan Lereng Sri Haryanti; Kabul Basah Suryolelono; Rachmad Jayadi
Semesta Teknika Vol 13, No 2 (2010): NOVEMBER 2010
Publisher : Universitas Muhammadiyah Yogyakarta

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.18196/jst.v13i2.712

Abstract

Soil movement mostly occurs especially during rainy season at the slope of Kalibawang irrigation channel at KM 15,9 in Kulon Progo district, Daerah Istimewa Yogyakarta. The slope movement causes damage at the school building, bridge and irrigation channel. Based on this fact, a research is necessary by modeling the slope at site of conducted. The objectives of this research are to identify the rainfall characteristic which triggering slope movement and to recognizes factor affecting the slope movement. Topography data, physical characteristic, and soil mechanic were applied as the input simulation models. Groundwater flow in slope was numerically simulated by using SEEP/W while the slope deformation simulated by SIGMA/W. Both SEEP/W and SIGMA/W were applied simultaneously in the numerical simulation. Rainfall design with appropriate return period was determined from rainfall annual daily maximum historical data recorded from 1985-2004, while distribution was completed by applying statical analysis on hourly rainfall data. The analysis of normal daily rainfall was determined based on daily rainfall data from Kalibawang rain gauge. Six models were applied as follow: initial condition (Rainfall Model I), heavy rainfall in short duration (Rainfall Model II), normal daily rainfall of 25 and 40 mm in long duration (Rainfall Model III), normal daily rainfall of 20 mm in long duration (Rainfall Model IV), heavy rainfall followed with normal daily rainfall of 20 mm (Rainfall Model V) and normal rainfall of 20 mm followed with heavy rainfall (Rainfall model VI). The result shows that at the research location, the maximum daily rainfall of 2-year-return period is 113,8 mm with dominant duration was 4 hour per day. This value was applied as Rainfall Model II. Based on the simulation the movement or deformation with Rainfall Model II, III, IV, V and VI is 0,22 m; 0,956 m; 1,01 m, ; 0,652 m, and 0,568 respectivally. It is concluded that at the research location, heavy rainfall in short duration gives small impact to slope movement or slope deformation and normal rain of 20 mm in long duration (Rainfall Model IV) is highly significant to the slope movement or slope deformation.
Analisis Kelongsoran Lereng Akibat Pengaruh Tekanan Air Pori di Saluran Induk Kalibawang Kulonprogo Hesti Subiyanti; Ahmad Rifa’i; Rachmad Jayadi
Semesta Teknika Vol 14, No 1 (2011): MEI 2011
Publisher : Universitas Muhammadiyah Yogyakarta

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.18196/st.v14i1.566

Abstract

During rainy seasons, landslide occurs every year in Talang Bawong, Kalibawang Irrigation Channel thatcan damage houses, school building, bridge and the channel. Considering this fact, a numerical analysis by modeling the slope at the site was conducted. The objectives of this research were to identify the rain characteristic in the research site and to recognize its influence towards the change of water pressure in soil as well as the slope failure. The input data of this analysis were slope topography, physical and mechanical properties of soil applied. Groundwater flow in the slope model was numerically simulated by using SEEP/W software. Designed rainfall with appropriate return period was determined by analizing the maximum daily rainfall data with the aid of HAVARA software, while rainfall depth distribution was completed by applying frequency analysis. The historical daily rainfall data (1985 – 2004) were obtained from Kalibawang rain stasiun. Six rainfall models, as follow: initial condition (no rain) (model I), heavy rain in a short duration (model II), normal rain 25 mm and 40 mm in a long duration (model III), normal rain 20 mm in a long duration (model IV), heavy rain followed by normal rain 20 mm (model V), and normal rain 20 mm followed by heavy rain (model VI) Were analyzed. The output of the simulation was water pressure distribution data, which in turn being used as input data in analyzing slope stability using the SLOPE/W software. The result of the research showed that the highest rainfall with 2-year-return period was 114 mm while the dominant duration was 4 hours/day, and it was applied in the model II. The result showed that, a normal rain in a long duration is more severely influenced the change in water pressure than a heavy rain in a short duration. The safety factors are 1,444 for no rain condition, 1,418 for 114 mm rain for 4 hours, 1,208 for 25 mm and 40 mm rains, 0,982 for 20 mm rain, 1,397 for heavy rain followed by normal rain, and 1,402 for normal rain followed by heavy rain. In addition, a 20 mm normal rain on the 61st  day resulted in the most severe influence on the slope failure. 
EVALUASI KINERJA POLA OPERASI WADUK (POW) WONOGIRI 2014 Dinia Anggraheni; Rachmad Jayadi; Istiarto Istiarto
TEKNISIA Vol. XXII, No. 1, Mei 2017
Publisher : Jurusan Teknik Sipil, Fakultas Teknik Sipil dan Perencanaan, Universitas Islam Indonesia

Show Abstract | Download Original | Original Source | Check in Google Scholar

Abstract

Wonogiri Reservoir is one of the reservoirs in Central Java which is a multifunctional reservoir. The reservoir serves many functions as flood control, irrigation and raw water supply, and hydropower (PLTA). For managing the fulfillment of these functions, Wonogiri Reservoir has a Reservoir Operating Rule to adjust the elevation and release discharge every mid-month. However, There was for the condition of Wonogiri Reservoir in October 2014. The water level of October 30, 2014, was at+126,66 m, while in Reservoir Operating Rule, the water level was supposed to be at +127,63 m. Therefore, the operating rule performance needs to evaluate, especially in 2014. The evaluation step began by conducting a water balance study with the demand for irrigation water and raw water, actual release, and inflow into the reservoir. The next step was optimizing the operating rule of the reservoir by the objective function of maximizing the comparison between release and demand for the fulfillment of irrigation water with 10 years data. The final step was evaluating the Wonogiri Reservoir Operating Rule in 2014 using a new operating rule generated from the optimization process. Based on the results of the study can be concluded that the inflow that occurred in 2014 can fulfill the needs of irrigation water and maintain elevation in accordance with the operating rule in 2014.
Model Hidrologi Terdistribusi untuk Simulasi Hidrograf Banjir Menggunakan Data Radar Yusuf Aji Pamungkas; Rachmad Jayadi; Joko Sujono
Jurnal Teknik Sipil Vol 26 No 3 (2019)
Publisher : Institut Teknologi Bandung

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.5614/jts.2019.26.3.9

Abstract

AbstrakPenerapan model hidrologi hujan-aliran terdistribusi sebagai bagian penting dari sistem peringatan dini banjir di wilayah lereng Gunung Merapi, membutuhkan input data hujan dengan resolusi spasial yang memadai. Oleh karena itu penggunaan data hujan dari ARR yang memiliki resolusi spasial yang rendah akan menyebabkan hasil hitungan hujan rata-ratanya (DAS) menjadi kurang teliti. Alternatif yang dapat dilakukan adalah menggunakan data hujan radar yang memiliki resolusi spasial dan temporal yang jauh lebih baik dibandingkan ARR. Pada penelitian ini dilakukan kajian hasil hitungan hidrograf banjir di wilayah lereng Gunung Merapi. Pemodelan hujan-aliran secara terdistribusi dilakukan dengan menentukan resolusi grid dari DAS dengan titik tinjau hitungan pada pos AWLR. Hujan pada setiap grid DAS dihitung sebagai rata-rata data hujan radar semua piksel di area masing-masing grid DAS. Simulasi limpasan permukaan DAS menggunakan paket perangkat lunak WMS v.10.1 dengan metode Hidrograf Satuan ModClark. Evaluasi ketelitian hidrograf banjir hasil simulasi didasarkan pada indikator kesalahan relatif debit puncak (peak discharge), waktu puncak (time to peak) dan volume limpasan permukaan (direct runoff volume). Hasil hitungan simulasi limpasan permukaan DAS menunjukkan bahwa perlu dilakukan telaah yang rinci terhadap faktor losses dan kesesuaian parameter hidrograf satuan, untuk menghasilkan kalibrasi model yang akurat. AbstractThe application of the distributed rainflow-runoff hydrological model as an important part of the early flood warning system in the slopes of Mount Merapi, requires rainfall data input with adequate spatial resolution. Therefore, the use of rainfall data from ARR which has a low spatial resolution will cause the results of the average rainfall (watershed) to be less precise. An alternative that can be done is to use radar rainfall data that has a far better spatial and temporal resolutions than the data from ARR. In this research, a study of the results of the flood hydrograph calculation in the slopes of Mount Merapi was conducted. The distributed rainflow-runoff modeling was done by determining the grid resolution of the watershed with a reference point of the calculation in the AWLR. Rain on each watershed grid was calculated as the average radar rainfall data of all pixels in the area of each watershed grid. Watershed surface runoff simulation used the WMS v.10.1 software package with the ModClark Unit Hydrograph method. The evaluation of the flood hydrograph simulation results' accuracy was based on indicators of the relative error of peak discharge, time to peak and direct runoff volume. The results of the watershed surface runoff simulation showed that a detailed study of the loss factors and the compatibility of the unit hydrograph parameter is necessary to produce an accurate model calibration.
KAJIAN VARIABILITAS CURAH HUJAN DI KAWASAN LERENG GUNUNG MERAPI DENGAN UJI MANN-KENDALL Endita Prima Ari Pratiwi; Joko Sujono; Rachmad Jayadi
INFO-TEKNIK Vol 13, No 1 (2012): INFOTEKNIK VOL. 13 NO. 1 2012
Publisher : Universitas Lambung Mangkurat

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.20527/infotek.v13i1.1810

Abstract

Rainfall is one of hydrology components that may be affected by climate change. The change of rainfall pattern can cause much impact on many fields. Many researches about global and regional climate change projection have been conducted. However, research about local scale of climate change based on climate character in local area is still necessary for a better result. Area of this research cover southwest slope of Merapi Mount, Java Island, Indonesia. Automatic rainfall data records from 1989 until 2008 of nine rainfall gauges in Merapi Mount’s southwest slope is available. Those data series this research is only adequate for climate variability analysis. The methods to detect trends in this research is non parametric test (Mann-Kendall test). The results show that at level of significance 5%, trend of rainfall in Mt. Merapi slope area is statistically not performing a specific pattern. Wet season occur every November until April while dry season occur every May until October. Neglect of trend signification, annual rainfall has decreace tendency. Rainfall amount in the beginning of wet season has increase tendency while rainfall amount in the middle of wet season and dry season have decreace tendency. Maximum daily and hourly rainfall also have decreace tendency.Spatially, annual rainfall and maximum daily rainfall increased from lower to higher elevation, from east to west and from south to north.