Hasil Pencarian  ::  Simpan CSV :: Kembali

"Pada dasarnya pilar jembatan yang telah dirancang dengan baik biasanya akan memiliki ketahanan yang baik terhadap beban rencana, baik beban aksial maupun beban lateral. Namun berdasarkan standar desain dalam Standar Nasional Indonesia (SNI) 1727:2013, langkah perhitungan untuk beban lateral berupa beban hidrodinamika banjir masih belum jelas, terutama untuk kecepatan aliran di atas 3,05 m/s. Oleh karena itu, dikhawatirkan desain pilar yang telah dibangun selama ini belum melalui proses perhitungan desain yang matang. Hal ini perlu diwaspadai dan segera dicarikan solusi agar ketika terjadi bencana seperti banjir bandang batuan di kemudian hari, struktur siap menerima beban dinamis yang besar. Salah satu solusi yang coba diadopsi dalam penelitian ini adalah dengan meningkatkan ketahanan struktur pilar jembatan melalui dua pilihan yaitu dengan menambah ukuran diameter pilar atau dengan menambah jumlah dan menyesuaikan posisi pilar terhadap rentang horizontal volume kontrol aliran banjir. Penelitian ini bertujuan untuk menemukan langkah yang paling tepat untuk menahan aliran banjir bandang batuan melalui analisis respon struktural, seperti tegangan, regangan, deformasi, dan reaksi momen pada pilar. Untuk mencapai tujuan tersebut digunakan software ANSYS 2019 R1 sebagai alat pemodelan. Selain itu juga dibuat beberapa skenario pemodelan dengan variasi langkah peningkatan tahanan dan kerapatan aliran banjir untuk mendapatkan hasil yang benar dan logis. Hasil penelitian menunjukkan bahwa langkah memperbesar diameter pilar merupakan pilihan yang tepat dalam meningkatkan ketahanan struktur, dan semakin meningkatnya kerapatan aliran banjir akan meningkatkan nilai respon struktur yang terjadi pada pilar.Basically, bridge piers that have been designed properly will usually have good resistance to design loads, both axial loads and lateral loads. However, based on the design standard in the Indonesian National Standard (SNI) 1727:2013, the calculation steps for lateral loads in the form of flood hydrodynamic loads are still unclear, especially for flow velocities above 3.05 m/s. Therefore, it is feared that the pillar designs that have been built so far have not gone through a mature design calculation process. This needs to be watched out for and immediately find a solution so that when a disaster occurs such as a flash flood of rocks in the future, the structure is ready to accept large dynamic loads. One of the solutions that is tried to be adopted in this study is to increase the resilience of the bridge pier structure through two options, namely by increasing the size of the diameter of the pillars or by increasing the number and adjusting the position of the pillars to the horizontal range of flood flow control volume. This study aims to find the most appropriate steps to withstand the flash flood flow of rocks through the analysis of structural responses, such as stress, strain, deformation, and moment reactions on the pillars. To achieve this goal, the ANSYS 2019 R1 software is used as a modeling tool. In addition, several modeling scenarios were made with variations in steps to increase resistance and flood flow density to get correct and logical results. The results showed that the step to increase the diameter of the pillars is the right choice in increasing the resilience of the structure, and the increasing flood flow density will increase the value of the structural response that occurs in the pillars."

"Larantuka is a subdistrict of East Flores Regency, on the eastern end of Flores Island, East Nusa Tenggara, Indonesia. Most of the land area of larantuka located on the foot hill of the Ile mandiri Mountain which is a flate area of the Larantuka Strait Larantuka is the risk area for the deluge floods disaster when the hard rainy happened. Deluge floods is the floods followed by rock material which is result of the landslide process. Because that, all the rivers which have river-basin is the Risk landslide area is the deluge floods rivers. Deluge floods disaster has a specific kind and to overcome the impact of deluge floods disaster it is needed the specific study. Indetification of the disaster risk area is needed in management of deluge floods disaster phases. Deluge floods disaster phases are prevention phase, early warning system phase, evacuation disaster victim phase and post disaster management phase. Prevent phase are done to prevent of deluge floods disaster with inprove the quality of the landcover area and build natural teras. If the landslide happen, the flow of surf ace stream are directed to cover the interest area."

"Dari perairan Tanjung Merah Sulawesi Utara telah berhasil dikumpulkan sekitar 21 jenis fauna Ekhinodermata yang mewakili 5 jenis Holothuroidea, 5 jenis Asteroidea, 4 jenis Echinoidea dan 7 jenis Ophiuroidea. Kelompok bintang mengular atau Ophiuroidea merupakan kelompok yang paling menonjol untuk daerah lamun. Berdasarkan hasil transek yang dilakukan di ketiga lokasi yang diamati ternyata kelompok bintang mengular (Ophiuroidea) menempati tingkat kekayaan jenis relatif tinggi. Secara umum baik dalam jumlah jenis ataupun dalam jumlah individu, fauna ekhinodermata di perairan Tanjung Merah Sulawesi Utara. Komposisi jenis, struktur komunitas, zonasi dan sebaran lokal akan didiskusikan dalam tulisan ini.

---

Notes on the Echinoderm Fauna of the Tanjung Merah Bay Waters Sulawesi Utara. A total of 21 species of echinoderms, belonging to of 5 species holothuroidea, 5 species of asteroidea, 4 species echinoidea and 7 species ophiuroidea have been found in the Tanjung Merah of Sulawesi Utara. The Ophiuroidea were relatively common in the sea grass zone. On the basis of population density, Ophiuroidea was the dominant group and relatively highest in the individual density. The species composition, community structure, zonation, and spatial distribution of echinoderm fauna are discussed in this paper."

"Peristiwa banjir yang melanda sebagian besar wilayah Barabai pada awal tahun 2021 lalu menimbulkan kerugian yang cukup besar. Selain dari genangannya, terjadi pula banjir bandang berkecepatan tinggi serta mengandung puing-puing di daerah hulu yang merusak sejumlah infrastruktur dan bangunan lainnya. Penelitian ini bertujuan untuk merancang bangunan air yang mampu mengendalikan banjir bandang tersebut dengan cara mengimplementasikan bangunan air yang sesuai dan dengan melakukan simulasi banjir pada aplikasi HEC-RAS. Selain kondisi ekstrem, simulasi banjir periode ulang 100 tahunan juga dijalankan sebagai alternatif desain. Hasil simulasi menunjukkan bahwa aliran berkecepatan tinggi mampu dikendalikan dengan menerapkan check dam dan tanggul. Kedua bangunan tersebut dirancang dari segi dimensi dan stabilitasnya terhadap guling, geser, dan overstress. Hasil analisis menujukkan bahwa bangunan kondisi ekstrem memiliki dimensi yang lebih besar dibandingkan kondisi banjir 100 tahunan. Bangunan air yang telah memenuhi syarat digambar sebagai rekomendasi penanggulangan banjir untuk wilayah Barabai di masa mendatang.

---

A flood that occurred in 2021 caused damage to Barabai and the surrounding area. Beside the inundation, fast moving water containing debris upstream is also responsible for the severe infrastructural damage and other buildings. This study aims to design appropriate structures to control the flash flood by implementing those structures and simulating the flood using HEC-RAS. In addition to extreme condition, this study also analyze the same event by using a smaller 100-year return period flood as an alternative. Simulation results show that the implementation of check dams and levees could control the velocity of flood. Both the check dams and levees are then designed to withstand oncoming forces by analyzing their stabilities against overturning moments, shear effects, and overstresses. The design process results in bigger dimension of structures designed to control the extreme condition. Drawings of structure are then commended to be used for future solution against flash flood."

"Moral judgment is part of the individual development that should be optimized. This research purpose was to know high school students' moral judgment stage and level espicially those who originate from the Malay father and mother in Langkat District, North Sumatra...."