What occurs along a river bend characterized by active silting_______________?
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Answer: D. scouring on concave side and silting on convex side
Explanation
Secondary helical currents in river bends force high velocity flow toward the outer concave bank. High velocity flow along the concave bank generates active bank erosion and bed scouring. Simultaneously, slower flow velocities along the inner convex bank cause sediment deposition and silting. River morphology dictates that curved channels experience asymmetric velocity distributions across their cross section. Centrifugal forces push surface water outward while bottom water flows inward toward the inner bend. Active meandering rivers continuously erode concave outer banks while building point bars on convex inner banks.
River training and bank protection works are essential along concave bends to prevent property loss. Navigation channels are typically maintained along outer concave bends where natural scouring keeps water deep. Understanding bend hydraulics helps civil engineers design stable bridge crossings and flood embankments. Option A scouring on concave side omits the corresponding silting occurring on the convex side. Option B silting on convex side ignores the severe scouring happening on the opposite concave bank. Option C scouring on both sides violates established river bend flow mechanics and sediment dynamics.
- Subject
- Engineering
- Category
- Civil Engineering
- Topic
- —
- Difficulty
- medium
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