FLOOD08704

• County: Statewide
• Basin: Statewide
• Title: Hydraulics of Bridge Waterways
• Date: 3/1/1978
• Prepared For: US
• Prepared By: USDOT
• Floodplain - Doc Type: Educational/Technical/Reference Information

FIGURES

1. Flow lines for typical normal crossing _ __ _ __ __ __ __ __ __ __ __ _ __ _ __ __ 3
2, Normal crossing: Wingwall abutments_ _ _ __ _ __ __ _ __ _ __ _ __ _ __ _ __ __ 4
3, Norm'll crossing: Spillthrough abutments____ ____ __ ____ __ ____ __ ___ 7
4, Types of flow encountered______________________________________ 8
5, Aid for estimating a,__ __ __ _ __ __ __ _ __ __ _ __ _ _ __ __ _ __ __ __ __ __ __ _ __ 11
6, Backwater coefficient base curves (subcritical flow)________________ 14
7, Incremental backwater coefficient for piers__ _ _ _ _ __ __ _ _ _ _ _ _ _ __ _ _ _ _ _ 15
8, Incremental backwater coefficient for eccentricity __ _ __ __ _ _ __ _ _ _ _ _ _ _ 16
9, Skewed crossing8__ _ _ ___ _ __ __ __ __ __ __ __ __ __ __ _ __ _____ __ __ _ _ _ __ _ 17
10, Incremental backwater coefficient for skew ____ __ __ __ __ _ __ _ __ _ __ __ _ 18
11. Ratio of projected to normal length of bridge for equivalent backwater
(skewed crossings)__ __ _ ___ __ _ _ _ _ ___ ___ __ _ _ _ __ __ ____ _ __ _ _ _ _ ___ 19
12, Differential waterlevel ratio base curves___ __ __ __ __ _ ____ _ __ _ __ _ __ _ 21
13, Distance to maximum backwater __ __ _ __ _ __ _ __ _ __ _ __ __ _ _ _ _ _ _ _ __ __ 25
14, Backwater multiplication factor for dual parallel bridges____________ Z7
15, Differential level multiplication factor for dual parallel bridges_ _ _ _ _ _ 28
16. Backwater with abnormal stage-discharge condition__ __ _ __ , __ __ __ __ 32
17, Effect of scour on bridge backwater______________________________ 36
18, Scour at wingwall abutment and single circular piers (model)________ 37
19. Cross section of scour at upstream side of bridge (model) __ __ _ __ __ __ 38
20, Correction factor for backwater with scour ____ _ __ __ _ __ __ _ ____ __ __ _ 39
21. Discharge coefficients for upstream girderin flow (case 1)___________ 42
22, Discharge coefficient for all girders in flow (case II) __ __ __ __ _ __ _ __ __ 43
23, Buoyant and horizontal forces moved these 80-foot spans downstream_ 45
24, Di8charge coefficients for flow over roadway embankments__ _ ,_ _ _ _ _ _ 46
25, Missouri River Bridge on route 1-70_____________________________ 47
26, Nottoway River Bridge on Virginia Route 40_____________________ 48
27, Flow concentration along upstream side of embankments at Big
Nichols Creek__ __ _ _ __ _ ____ _ _ ____ _ __ _ ___ _ __ __ _ _ _ _ __ _ __ _ __ __ __ 51
28, Extent of scour measured after the flood at Big Nichols Creek_____ __ 52
29, Model of a spur dike___________________________________________ 52
30, Chart for determining length of spur dikes_ _ __ _ _ __ _ _ _ __ _ _ _ _ __ _ __ _ _ 54
31. Spur dikes on model of Tarbela Bridge, Indus River, West Pakistan_ _ 55
32, Spur dike on 450 skewed bridge over Susquehanna River, Nanticoke,

Pa______________________________________________,__________ 55
33, Plan and cross section of spur dike_ __ __ _ _ _ _ _ __ _ _ _ _ _ _ _ _ _ __ __ _ __ __ 56
34, Tentative backwater coefficient curve for type II flow _ _ _ _ _ _ _ _ _ _ _ _ _ _ 57
35, Status of U ,S. Geological Survey nationwide flood frequency project- _ 60
36. Example 1: Plan and cross section of normal crossing______________ 66
37. Example 3: Plan of skewed crossing____________________________~ 70
38, Examples 1-3: Conveyance and area at section L_________________ 71
39, Example 4: Cross section of eccentric river crossing__ __ __ _ __ _ _ __ _ __ 72
40, Example 4: Stage-discharge curve for river at bridge site__ __ __ _____ 72
41. Example 4: Area and velocity head coefficient__ __ ____ __ __ ____ ____ 74
42, Example 4: Conveyance at section L_____ __ __ __ __ __ __ __ __ __ _____ 74

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