online_contraction_scour_live_bed:  Contraction scour under live bed conditions
using modified Laursen 1960 equation


Modified Laursen formula


ys / y1 = ( Q2 / Q1 ) 0.86 (W1 / [W2) k1  -  ( yo / y1 )

[ yo, y1, Q and W in any consistent set of units ]
[ S1 in m/m or ft/ft ]
[ T in °C or °F ]
[ D50 in mm or ft ]


Reference:

Evaluating Scour at Bridges, FHWA Hydraulic Engineering Circular No. 18,
Fifth Edition, 2012.



INPUT DATA:      [Description]     [Sample Input]

Select:      

Mean flow depth below the bridge, before scour yo :      

 
Warning: Undefined variable $depthunits in /var/www/html/ponce/enlineacontraccionsocavacionlechomovil.php on line 398

Mean flow depth upstream of the bridge y1 :      

 
Warning: Undefined variable $depthunits in /var/www/html/ponce/enlineacontraccionsocavacionlechomovil.php on line 404

Discharge upstream of the bridge (only in the main channel) Q1 :      

 
Warning: Undefined variable $dischargeunits in /var/www/html/ponce/enlineacontraccionsocavacionlechomovil.php on line 410

Discharge in the contracted section Q2 :      

 
Warning: Undefined variable $dischargeunits in /var/www/html/ponce/enlineacontraccionsocavacionlechomovil.php on line 416

Bottom width in the section upstream of the bridge W1 :      

 
Warning: Undefined variable $widthunits in /var/www/html/ponce/enlineacontraccionsocavacionlechomovil.php on line 422

Bottom width in the contracted section, excluding piers W2 :      

 
Warning: Undefined variable $widthunits in /var/www/html/ponce/enlineacontraccionsocavacionlechomovil.php on line 428

Energy slope in the main channel upstream S1 :      

 
Warning: Undefined variable $slopeunits in /var/www/html/ponce/enlineacontraccionsocavacionlechomovil.php on line 434

Median diameter of the bed material D50 :      

 
Warning: Undefined variable $dfiftyunits in /var/www/html/ponce/enlineacontraccionsocavacionlechomovil.php on line 443

Select water temperature T :      

OUTPUT:


Warning: Undefined variable $unitsystems in /var/www/html/ponce/enlineacontraccionsocavacionlechomovil.php on line 483
SI units (metric)

Warning: Undefined variable $temperature in /var/www/html/ponce/enlineacontraccionsocavacionlechomovil.php on line 487
Water temperature T: 0°C


Contraction scour depth
under live bed conditions
ys :   
Warning: Undefined variable $scourdepth in /var/www/html/ponce/enlineacontraccionsocavacionlechomovil.php on line 529

Deprecated: substr(): Passing null to parameter #1 ($string) of type string is deprecated in /var/www/html/ponce/enlineacontraccionsocavacionlechomovil.php on line 529
 
Warning: Undefined variable $depthunits in /var/www/html/ponce/enlineacontraccionsocavacionlechomovil.php on line 529



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