FLOOD04125

• County: Statewide
• Basin: Statewide
• Title: Interim Procedures for Evaluating Scour at Bridges
• Date: 9/1/1988
• Prepared By: Federal Highway Administration
• Floodplain - Doc Type: Educational/Technical/Reference Information

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EXHIBIT III-B, 2 of 2

SUMMARY OF RESULTS:

BRIDGEIl<

6622

DATE:Jul-88

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I DEPTH OF SCOUR IN FEET
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SCOUR TYPE/EQ. USED I Q50 Q100 I Q500
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CONTRACTION SCOUR: I MIll MAX MIN MAX I HIN MAX
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EQ1 LAURSENS I 1.65 1.71 1.96 2.05 I 3.96 4.10
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.-----.-...--.------.---------..----- ------------------------.-...-----
ABUTKENT SCOUR: I RIGHT LEFT RIGHT LEFT I RIGHT LEFT
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*EQ3 LIU ET ALL(SSA) .-10 .-10 .-10 .-10 .-10 .-10
*EQ5 LIU & GILL (VA) .-10 .-10 .-10 .-10 .-10 .-10
*EQ7 SIMP. LAURSENS .-10 .-10 .-10 .-10 .-10 .-10
*EQ10 CASE 5 a/y>25 .-7 .-7 .-7 .-7 .-7 .-7
*EQ9 CASE 4 4.7 3.4 5.5 4.7 9.1 10.1

-------------------- --------...--------------------- --------------

PIER SCOUR:

*EQl1 CSU 5.92 6.18 6.75 J
EQ12 CHANG 6.18 6.43 7.10 I
EQ13 MAX CHANG 6.90 6.90 6.90 I
LAURSEN & TOCH 5.04 5.17 5.60 I
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-------------------- --....-.................... ----------------- ---...--------1
CHECKS : I
NOUDE NO. 0.28 0.28 0.27 I
AllYl RIGHT 0.55 0.46 0.37 I
A2jY1LEFT 0.37 0.35 0.30 I
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NOTES:
.-1 - VERnCAL ABUTMENT EQ3 DOES ROT APPLY
#2 . FROUDE NO. IS >0.6, EQ3 DOES NOT APPLY
.-3 - AjY>25. EQ3 DOES NOT APPLY
llI4 - FOR SPILL SLOPE ABUTMENT EQ5 DOES NOT APPLY
.-5 - NOUDE NO. >0.8 EQ5 DOES NOT APPLY
1J6 - AjY>25 EQ5 DOES NOT APPLY
.-7 - AjY<25 EQ10 DOES NOT APPLY
#8 - NOT A CASE 4 SITUATION
.-9 - AS 1l1-1l2, NO CONTRACTION SCOUR
.-10- NOT COMPUTED SINCE ITS A CASE 4 SITUATION

* - THIS EQUATION'S VAWE lIAS BEEN INCREASED BY 30t TO
OBTAIN MAXIMUK SCOUR.
CASE 4 EQUATION SOLUTION ACCURACY + or . O. 2! and MAXIMUM OF
100ft SCOUR DEPTHS.
VA VERTICAL ABUTMENT
SSA SPILL SLOPE ABUT

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