کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
4532740 1325143 2011 14 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Size and settling velocities of cohesive flocs and suspended sediment aggregates in a trailing suction hopper dredge plume
موضوعات مرتبط
مهندسی و علوم پایه علوم زمین و سیارات زمین شناسی
پیش نمایش صفحه اول مقاله
Size and settling velocities of cohesive flocs and suspended sediment aggregates in a trailing suction hopper dredge plume
چکیده انگلیسی

A field experiment was conducted to quantify settling velocities, aggregate states, and flocculation within a hopper dredge plume. Particular interest was in determining the abundance of dense, bed aggregates suspended from the consolidated bed during dredging. A suspended sediment plume from the hopper dredge Essayons was sampled for a period of 90 min after dredging. Settling velocities and suspended particle sizes were quantified through sampling with the Particle Imaging Camera System (PICS) and automated image processing routines. The sediment plume was identified and a profiling instrumentation frame was positioned within the plume using Acoustic Doppler Current Profiler (ADCP) backscatter. Results indicated that suspended bed aggregates (defined by densities of 1200–1800 kg m−3) represented 0.2–0.5 of total suspended mass, and flocs (densities<1200 kg m−3) represented 0.5–0.8 of total suspended mass. The peak diameter of bed aggregates and flocs occurred near 90 and 200 μm, respectively, corresponding to peak settling velocities of about 1 mm s−1 in each case. Floc settling velocities increased with particle size d1.1, while bed aggregate settling velocity increased like d1.3.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Continental Shelf Research - Volume 31, Issue 10, Supplement, 15 July 2011, Pages S50–S63
نویسندگان
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