Applications of Flow Net
Flow net applications include Calculation of uplift pressure, Exit gradient / Piping, Heaving and Pore Water pressure.
Simple, Quick & Easy
Hey, I'm Aditya. Do you want to learn concepts easily?
Learn with APSEd and score high!
Video Lectures & Study Material
Practice Questions & Mock Tests
Formula Cards & Assessment Tests
Exclusive Doubt Support
What is flow net?
Flow net represents the flow of water through a soil graphically. In field, under sheet piles, under dams and under masonry structures flow is not 1D, it may be 2D/3D
What are the applications of Flow net?
• Calculation of uplift pressure
• Exit gradient/Piping
• Pore Water pressure
Calculation of uplift pressure
It is pore water pressure and it acts vertically upward direction due to residual pressure head.
• In case of stability of dam, uplift pressure reduces the stability
• We can provide a cutoff wall at upstream side of structure to reduce the uplift pressure
Exit gradient / Piping
At downstream, flow lines are vertically upwards so there the flow channel is very small in length but has same head loss. Hence boiling can occur, further the erosion of particles will occur and a pipe kind of structure will form from downstream to up.
• Structure may fail catastrophically, hence large factor of safety would be used in case of piping.
• To avoid this a cutoff wall would be placed at downstream side of the
Heaving and Pore Water Pressure
At downstream due to seepage from upstream, the buoyant weight would be lesser than the seepage force. There we place the graded filters to avoid the heaving.
Pore water pressure can also me measured using flownet