scholarly journals Scour Depth Estimation on Abutment With HEC RAS and Some Empirical Equation

2020 ◽  
Vol 17 (1) ◽  
pp. 87-95
Author(s):  
Indra Agus ◽  
Munafri Alwys ◽  
Wisafri Wisafri ◽  
Dalrino Dalrino ◽  
Noftar Yolanda ◽  
...  

Toe Scour around abutment will be very dangerous and cause loss of stability on the bridge. The case of structure failure on Batang Kalu bridge in Korong Pasa Usang Nagari Kayu Tanam, Padang Pariaman Regency on Monday (10 December 2018) is a clear example of toe scouring. A case study of toe scour was on the Batang Kalu River bridge structure has been carried out. Rainfall data closest to the study location, Kandang Empat Station was used to minimize the errors in the calculation of flood discharge design. Numerical modeling with HEC RAS and scouring estimation with some empiric equation was conducted to predicting scour depth on abutment. Simulation results show scour depth results to an average of 2.731 m and close to the scour depth that occurred in the field (2.83 m). Results showed that the local scouring in the Batang Kalu River bridge structure can be suspected as the influence of the increasing river steepness. Discharge that is triggered by heavy rain with a long duration and increased river flow velocity due to steepness has the potential to create a very intense scouring. Increasing of steepness may have been caused by sand mining activities in the upper reaches. Further studies are needed to see the potential slope changes due to exploitation in the Batang Kalu River upper reaches

Author(s):  
Muh. Iqbal Latief ◽  
Sultan Djibe ◽  
Arsyad Genda

AbstractThe flood disaster that struck the Province of South Sulawesi (South Sulawesi) at the end of January 2019, was the worst natural disaster in the past 20 (twenty) years. Of the 24 (twenty four) districts and cities in South Sulawesi, there are 6 (six) districts and cities experiencing very poor conditions, namely the Regencies of Jeneponto, Maros, Gowa, Takalar, Barru and Makassar. As a result of this disaster, tens of thousands of families lost their homes, property was destroyed, social facilities such as schools and houses of worship were also severely damaged and some were destroyed. Even more pathetic, because more than a hundred people died. This results from an imbalance of ecosystems causing serious problems. Community understanding of the need to maintain ecosystem balance is still very low coupled with the socioeconomic situation which makes the community more pragmatic. The problem is, how do you increase the awareness of the community in maintaining the balance of the ecosystem? And how to foster disaster-conscious attitudes and behavior for the community, especially in disaster-prone areas? Therefore, the writing of this article aims to comprehensively examine people's attitudes related to maintaining ecosystem balance and fostering disaster-conscious behavior in the community, especially in disaster-prone areas as an alternative to disaster risk management. The method used is qualitative with the type of case study studies. The selection of informants is done purposively and the data processed are primary and secondary. From the results of this study it was found, the increasingly severe environmental damage became the main trigger of natural disasters that occurred in South Sulawesi at the end of January 2019. This environmental damage, is dominant because of the very exploitative behavior of the community towards the environment. For example, what happened in Gowa district, the big floods that occurred because around the Jeneberang River and Bili-Bili Dam areas - sand mining activities have been going on for decades. Likewise, the Mount Bawakaraeng area, which used to function as a buffer against flooding, has long been deforested as a result of causing landslides whenever there is heavy rain. This condition also occurs in the districts of Jeneponto, Maros and others - these areas are vulnerable to heavy rainfall. To overcome this serious problem, one alternative is to form community groups that are aware of disasters. This strategy of forming disaster awareness groups, by combining approaches from above (government) and from below (the community)   Musibah banjir yang melanda Provinsi Sulawesi Selatan (Sulsel) di akhir Januari 2019, merupakan bencana alam yang terparah selama kurun waktu 20 (dua puluh) tahun terakhir ini. Dari 24 (dua puluh empat) kabupaten dan kota di Sulsel, ada 6 (enam) kabupaten dan kota mengalami kondisi sangat memprihatinkan yaitu Kabupaten Jeneponto, Maros, Gowa, Takalar, Barru dan Makassar. Akibat dari bencana ini, puluhan ribu keluarga kehilangan tempat tinggal, harta benda musnah, fasilitas sosial seperti sekolah dan rumah ibadah juga rusak berat dan ada yang hancur. Lebih mengenaskan, karena menimbulkan korban jiwa meninggal dunia lebih dari seratus orang. Hal ini akibat dari ketidakseimbangan ekosistem menyebabkan masalah yang serius. Pemahaman masyarakat tentang perlunya menjaga keseimbangan ekosistem, masih sangat rendah ditambah lagi dengan situasi sosial ekonomi yang membuat masyarakat makin pragmatis. Masalahnya, bagaimana cara meningkatkan kepedulian warga masyarakat dalam menjaga keseimbangan ekosistem? Dan bagaimana menumbuhkan sikap dan perilaku sadar bencana bagi masyarakat khususnya di kawasan yang rawan bencana? Karena itu, penulisan artikel ini bertujuan untuk mengkaji secara komprehensif sikap masyarakat terkait dengan kepedulian menjaga keseimbangan ekosistem dan menumbuhkan perilaku sadar bencana di masyarakat khususnya di daerah-daerah yang rawan bencana sebagai alternatif manajemen risiko bencana. Metode yang digunakan adalah kualitatif dengan jenis kajian studi kasus. Pemilihan informan dilakukan secara purposif dan data yang diolah adalah primer dan sekunder. Dari hasil penelitian ini ditemukan , makin parahnya kerusakan lingkungan menjadi pemicu utama dari bencana alam yang terjadi di Sulsel akhir Januari 2019.. Kerusakan lingkungan ini, dominan karena perilaku masyarakat yang sangat eksploitatif terhadap lingkungan. Misalnya saja yang terjadi di kabupaten Gowa, banjir besar yang terjadi karena di sekitar kawasan Sungai Jeneberang dan Dam Bili-Bili – kegiatan penambangan pasir sudah berlangsung puluhan tahun lamanya. Begitu juga kawasan Gunung Bawakaraeng yang tadinya berfungsi sebagai penyangga banjir, karena sudah lama digunduli akibatnya menimbulkan longsor setiap ada hujan deras. Kondisi ini juga terjadi di Kabupaten Jeneponto, Maros dan lainnya – daerah-daerah ini rentan terhadap curah hujan yang besar. Untuk mengatasi masalah serius ini, maka salah satu alternatifnya dengan membentuk kelompok-kelompok masyarakat yang sadar bencana. Strategi pembentukan kelompok sadar bencana ini, dengan memadukan pendekatan dari atas (pemerintah) dan dari bawah (masyarakat)


2018 ◽  
Vol 8 (3) ◽  
pp. 117
Author(s):  
Hayat Kareem Shukur Azawi ◽  
Dawood Eisa Sachit

One of the most important reasons for the frequent occurrence of rainwater flooding in Baghdad in general and Al-Huryai, part of Baghdad, in particular is the lack of runoff drainage systems in conventional pavement. Incidents of flooding have occurred on an average three times per year in many parts of the town due to heavy rain of high intensity and short duration. Using permeable pavement will help to control flooding and improve public health. The objective of this study is to investigate the important factors that describe the possible implementation of permeable pavement in Al-Huryai city using PCSWMM software and to quantify the effectiveness of this technique on the hydrologic response of the case study by comparing the simulation analyses of the site under its undeveloped condition, after development, and after implementing permeable pavement. The simulation results showed that permeable pavement approach has a significant impact on runoff reduction.


Author(s):  
Nabil Mohareb ◽  
Sara Maassarani

Current architecture studios are missing an important phase in the education process, which is constructing the students’ conceptual ideas on a real physical scale. The design-build approach enables the students to test their ideas, theories, material selection, construction methods, environmental constraints, simulation results, level of space functionality and other important aspects when used by real target clients in an existing context. This paper aims to highlight the importance of using the design-build method through discussing a design project case study carried out by the Masters of Architecture design programme students at Beirut Arab University, who have built prototype units for refugees on a 1:1 scale.


Water ◽  
2021 ◽  
Vol 13 (11) ◽  
pp. 1449
Author(s):  
Alena Gessert ◽  
Imrich Sládek ◽  
Veronika Straková ◽  
Mihály Braun ◽  
Enikő Heim ◽  
...  

Estimation of the catchment area of a karst spring is not possible in all areas for various reasons. The Slovak Karst is protected by the highest degree of protection and karst springs are used as a source of drinking water for the second largest city in Slovakia, Košice. From this reason, no results on ionic runoff or chemical denudation have been published from this area and the most appropriate way to obtain information about the denudation rate is to determine the ionic runoff. This paper provides an overview of ionic runoff results based on sampling and analysis of karst water from six springs in the period November 2013–October 2016 (three hydrological years) and periodic measurements. Springs have significantly fluctuated flow rates from 0 L/s in summer and autumn up to 192 L/s, and episodic events during the snow melting and heavy rain in the spring of 2013 are also known (more than 380 L/s). The total value of ionic runoff for the area of 40,847 m3/y.km2 is comparable with the Vracanska Plateau in Bulgaria, which lies at a similar altitude and with a similar amount of precipitation.


Water ◽  
2021 ◽  
Vol 13 (15) ◽  
pp. 2019
Author(s):  
Hossein Hamidifar ◽  
Faezeh Zanganeh-Inaloo ◽  
Iacopo Carnacina

Numerous models have been proposed in the past to predict the maximum scour depth around bridge piers. These studies have all focused on the different parameters that could affect the maximum scour depth and the model accuracy. One of the main parameters individuated is the critical velocity of the approaching flow. The present study aimed at investigating the effect of different equations to determine the critical flow velocity on the accuracy of models for estimating the maximum scour depth around bridge piers. Here, 10 scour depth estimation equations, which include the critical flow velocity as one of the influencing parameters, and 8 critical velocity estimation equations were examined, for a total combination of 80 hybrid models. In addition, a sensitivity analysis of the selected scour depth equations to the critical velocity was investigated. The results of the selected models were compared with experimental data, and the best hybrid models were identified using statistical indicators. The accuracy of the best models, including YJAF-VRAD, YJAF-VARN, and YJAI-VRAD models, was also evaluated using field data available in the literature. Finally, correction factors were implied to the selected models to increase their accuracy in predicting the maximum scour depth.


2010 ◽  
Vol 2010 ◽  
pp. 1-14 ◽  
Author(s):  
Mohammad Ali Badamchizadeh ◽  
Iraj Hassanzadeh ◽  
Mehdi Abedinpour Fallah

Robust nonlinear control of flexible-joint robots requires that the link position, velocity, acceleration, and jerk be available. In this paper, we derive the dynamic model of a nonlinear flexible-joint robot based on the governing Euler-Lagrange equations and propose extended and unscented Kalman filters to estimate the link acceleration and jerk from position and velocity measurements. Both observers are designed for the same model and run with the same covariance matrices under the same initial conditions. A five-bar linkage robot with revolute flexible joints is considered as a case study. Simulation results verify the effectiveness of the proposed filters.


2012 ◽  
Vol 9 (4) ◽  
pp. 259-276 ◽  
Author(s):  
N.T. Lan-Anh ◽  
J. Boxall ◽  
A. Saul ◽  
P. Willems
Keyword(s):  

1999 ◽  
Vol 10 (2) ◽  
pp. 402-409 ◽  
Author(s):  
A.F. Atiya ◽  
S.M. El-Shoura ◽  
S.I. Shaheen ◽  
M.S. El-Sherif

Symmetry ◽  
2021 ◽  
Vol 13 (5) ◽  
pp. 854
Author(s):  
Raquel S. Rodríguez ◽  
Gilberto Gonzalez Avalos ◽  
Noe Barrera Gallegos ◽  
Gerardo Ayala-Jaimes ◽  
Aaron Padilla Garcia

An alternative method to analyze a class of nonlinear systems in a bond graph approach is proposed. It is well known that the analysis and synthesis of nonlinear systems is not a simple task. Hence, a first step can be to linearize this nonlinear system on an operation point. A methodology to obtain linearization for consecutive points along a trajectory in the physical domain is proposed. This type of linearization determines a group of linearized systems, which is an approximation close enough to original nonlinear dynamic and in this paper is called dynamic linearization. Dynamic linearization through a lemma and a procedure is established. Therefore, linearized bond graph models can be considered symmetric with respect to nonlinear system models. The proposed methodology is applied to a DC motor as a case study. In order to show the effectiveness of the dynamic linearization, simulation results are shown.


Measurement ◽  
2021 ◽  
Vol 172 ◽  
pp. 108944
Author(s):  
Masih Zolghadr ◽  
Seyed Mohammad Ali Zomorodian ◽  
Reza Sha'bani ◽  
H. Md. Azamatulla
Keyword(s):  

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