Transport of estuarine sediment have a highly complex method, which is the combined effects result of periodically reciprocating flow, ocean waves, and the electrochemical characteristic of sea water [1]. Settling velocity (SV) is such a parameter fundamental for sediment researchers so that its accurate resolution has been regarded as a top priority in correcting modelling numerical and conceptual understanding of fine sediment dynamics [2] [3]. The goal of this study is to analyze the effect of salinity levels on the settling velocity of fine sediment grains in the Ciliwung estuary, Jakarta. The method used is direct measurement using the hydrometer analysis method. The result of experiment shows salinity levels affect the settling velocity of fine sediment grains in the Ciliwung estuary. The higher salinity, more faster the settling velocity of fine sediment grains. The average settling velocity at distilled water salinity 0 ppt is 1.083 mm/minute, sea water with salinity 0.3 ppt is 1.537 mm/minute, and sea water with salinity of 0.6 ppt of 1.561 mm/minute.
Work at height is a job with a high risk of accidents, such as in the formwork aluma system. Weak supervision and a lack of knowledge of the workforce on potential hazards and risk control of the formwork aluma system are some of the causes of the high incidence of work accidents in this work. This research was conducted on the formwork aluma system of the BRI Gatot Subroto tower project, South Jakarta. The goal is to determine the potential hazards and risk control of aluma system formwork. Risk analysis is carried out using the AS / NZS 4360: 2004 standard to determine the level of risk to the potential hazards of the aluma system formwork. Potential hazards in the formwork aluma system are falling, bumping, being cut, punctured and crushed, with the level of risk being at high, substantial, medium and low levels. Risk control is carried out by the control hierarchy, namely elimination, substitution, engineering, administration, and control of PPE.
Beton menurut salah satu sumber yaitu SNI 2847:2013 dapat memiliki arti campuran semen Portland atau semen hidrolisis yang lain, agregat halus, agregat kasar, dan air, dengan atau tanpa bahan campuran tambahan (mixture). Tujuan dari penelitian ini adalah menganalisis sifat fisis dari agregat halus pasir dan limbah plastic seperti berat jenis SSD, berat jenis SSD, berat isi, Analisa ayak, kadar air, dan kadar lumpur. Metode yang dilakukan adalah menggunakan metode observasi dengan cara melakukan pengujian langsung di laboratorium sesuai Standar Nasional Indonesia (SNI). Hasil yang diperoleh menunjukkan bahwa pada penelitian agregat halus pasir dengan pengujian berat jenis SSD sebesar 2,55; penyerapan air sebesar 2,35%; berat isi / massa jenis lepas sebesar 1,33 Kg/liter; berat isi / massa jenis padat sebesar 1,56 Kg/liter; analisa ayak sebesar 2,90; kadar air sebesar 1,93%; dan kadar lumpur sebesar 3%. Nilai tersebut memenuhi standar spesifikasi pembuatan beton berdasarkan SNI 1969:2008. Sedangkan penelitian yang dilakukan terhadap agregat halus limbah plastik tidak memenuhi spesifikasi dan dapat dilihat pada pembahasan maupun lampiran.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.