Introduction
The Bridge, in its reimagined form for Flood Modeller v7.3 onwards, is an universal bridge structure unit, which enables the modeller to simulate the discharge and headloss from a watercourse flowing through a bridge, using a variety of formulations and associated features. For instance, bypass flow over the top of the bridge, or through a flood relief culvert can be included, as can additional headloss caused by a partially blocked opening.
Prior to Flood Modeller v7.3, the three available formulations were available as separate hydraulic units, with any overspill, flood relief culverts and blockages modelled as separate entities in parallel (or series, in the case of a blockage). The [new] Bridge unit enables all of these to be modelled (and modified) within a single unit, making the modelling process more streamlined. Although the pre-existing bridge units are still available, they will be phased out as there is no functionality contained within them which is not available in the Bridge unit. Therefore, it is strongly recommended that all new bridges newly added to models from Flood Modeller v7.3 onwards use the new Bridge unit.
If a more complex schematisation requiring additional features in parallel, for instance, is required, then this is still possible, although it is envisaged that the need for this will be greatly lessened.
Please download an example of the [new] Bridge unit within a 1D river network by clicking on [new]Bridge.
In the majority of cases, the integrated Bridge, being a combined bridge and overspill, etc. obeys the standard Flood Modeller connectivity rules of a structure, can simply be added in the middle of an existing river reach, and is usually connected to a river section upstream and downstream, although it can be connected to any other hydraulic unit or structure (see following notes).
Node label #1 (Upstream node label) must exist, and be coincident with [same name as] the hydraulic unit node label immediately upstream of it. Usually, this is a RIVER (or other channel, e.g. CONDUIT) section, in which case this must have a distance to next value of zero. However, it could also be the downstream node label [Label #2] of another structure, or any node of an adjoining junction (or reservoir). This node label must exist in these two places, but nowhere else in the network. See also subsequent notes about remote node labels.
Node label #2 (Downstream node label) must exist, and be coincident with [same name as] the hydraulic unit node label immediately downstream of it. Usually, this is a RIVER (or other channel, e.g. CONDUIT) section, in which case this must have a positive distance to next value. However, it could also be the upstream node label [Label #1] of another structure, or any node of an adjoining junction (or reservoir). This node label must exist in these two places, but nowhere else in the network. See also subsequent notes about remote node labels.
Node label #3 (Upstream remote node label). The function of remote node labels is to refer to a channel section from which to obtain velocities for the bridge afflux calculations. If absent, this defaults to the same as Node Label #1, so if Label 1 is coincident with a channel node (as it will be in the majority of cases), Label 3 is not required. However, if Label 1 is coincident with a non-channel section, i.e. structure, junction or reservoir (or boundary – not recommended!), then Label 3 should be set to the label of the hydraulically-nearest channel section upstream (e.g. the section immediately upstream of the adjoining structure/junction)
Node label #4 (Downstream remote node label). See above for meaning. If absent, this defaults to the same as Node Label #2, so if Label 2 is coincident with a channel node (as it will be in the majority of cases), Label 4 is not required. However, if Label 2 is coincident with a non-channel section, i.e. structure, junction or reservoir (or boundary – not recommended!), then Label 4 should be set to the label of the hydraulically-nearest channel section downstream (e.g. the section immediately downstream of the adjoining structure/junction)
To insert a new Bridge easily, the user interface has been intelligently designed to facilitate this. It is assumed that your network already contains RIVER cross sections immediately upstream and downstream of the bridge, and that the distance between them (distance to next of the upstream section) is equal to the length of the bridge (i.e. in the direction of flow). If not, it is recommended to copy the appropriate section(s) and apply the correct distances. The procedure then is:
Select the upstream and downstream RIVER sections
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Select Bridges
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from the 1D River Build menu…
This then automatically inserts a bridge unit with the following data populated:
Bridge node labels are set to those of the upstream and downstream river sections, respectively
Upstream and downstream bridge face sections are copied from Upstream and Downstream river sections
Bridge length is set to the previous “distance to next section” of the upstream RIVER section
“Distance to next section” of the upstream RIVER section is set to zero
Thus, the connectivity is already valid. As a minimum, the following data are required to be added manually:
Bridge Name. Note this is different from the node labels, and is recommended to be what the bridge is commonly known as, e.g. Upton Bridge.
Bridge type (ARCH, USBPR or YARNELL) – this determines the formulation used to calculate the afflux
Bridge opening data
Information about the optional data follows both below and in the technical reference.
Notes
Remote Nodes
Remote nodes are not required when connecting a Bridge unit directly to a RIVER section (i.e. when the Bridge Node Labels are equal to the RIVER section Node Labels). The function of a remote node label is to inform the computations from where to obtain velocities in order to calculate the afflux. Since for Bridges (and hydraulic structures in general), velocities are not calculated explicitly in Flood Modeller (velocities are only explicitly calculated in channel sections – RIVERs and CONDUITs), one defaults to using velocity from the “best available” channel section, usually the nearest channel section upstream and downstream, respectively. Since this is not always an obvious or unique section, we need to tell the computations from where to obtain these. The exception to this being, of course, when the Bridge is attached directly to a channel section, upstream and/or downstream. A typical occurrence of this would be when schematising a bypass/overtopping flow via a spill or weir unit in parallel. This is prevalent in models containing “old-style” bridges, although with the Bridge, since the facility exists to include an integrated spill, it is envisaged the need for these will be considerably reduced.
Formulation
The formulations used to calculate afflux can be significant in their nature, and also produce differing outcomes; as such, there is no hard and fast rule over when to use which formulation, but a rough guide is as follows:
ARCH – this is typically suited to smaller stone or solid bridges with an arched opening. Uses the formulation derived from research published in HR Wallingford: Afflux at Arch Bridges (1988).
USBPR - this is typically suited to larger highway bridges with a flatter opening. Uses the formulation derived from research published in USBPR: Hydraulics of Bridge Waterways (1958, Revised 1978), also known as Bradley’s equation.
YARNELL (Pier-Loss) – this uses Yarnell’s Equation, USDA: Bridge Piers as Channel Obstructions (1934), and is primarily suited to bridges where the primary influence on headloss is the central pier(s). Thus, such a bridge must consist of at least two openings (one pier).
There are of course situations where none of the above uniquely describes the situation being modelled, and therefore a combination of user judgement, experience and calibration is often necessary to determine the most appropriate approach.
Cross-chainage in Bridge sections
Note that, since 1D River solver effectively performs computations at a point along the length of a channel, the horizontal alignment of spill data and Flood Relief culverts is arbitrary for the computations (e.g. if spill data extends horizontally from -200 to -100, it would have the same computational effect if this was translated so that it extended from 100 to 200); all the computations “see” is a total width and the respective elevations. However, for visualisation (as well as QA) purposes, it is recommended to align from a consistent horizontal offset.
Note, however, that the bridge openings and cross section data must be aligned with each other as this defines where the openings sit relative to the bed.
For example, the following two examples will be treated equivalently, despite the different offsets of the spill and relief culverts:
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However, since the bridge opening in the following example is aligned differently with the bed, this is not equivalent to the previous two
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Data
Field name | data name (see Data File format section below) | Function | Constraints / notes | |
Overview (visible on all tabs) | ||||
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Bridge Name | BridgeName | Reference/Name of bridge | Mandatory, but not used in the computations | |
Bridge type | Formulation | Denotes formulation of bridge afflux calculations to use | USBPR, ARCH or YARNELL | |
Description | comment | Description of bridge/context (optional) | Optional; Not used in the computations | |
View plot | n/a | Toggles plot display on/off | Default is on | |
Node labels: | ||||
Upstream | Label1 | u/s connection node label | ||
Downstream | Label2 | d/s connection node label | ||
Upstream Remote | Label3 | u/s remote node label – usually nearest channel (RIVER/CONDUIT) section upstream | optional; not required if this is coincident with the bridge | |
Downstream Remote | Label4 | d/s remote node label – usually nearest channel (RIVER/CONDUIT) section downstream | optional; not required if this is coincident with the bridge | |
Edit… | n/a | Opens the node label editor. | NB This must be used to edit node labels – they cannot be edited in situ | |
Cross-section tab
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Upstream/downstream sub-tabs (ith row in coordinate table of kth section specified here; up to 400 rows [cross section points] are allowed; up to four cross-sections may be stored in the network datafile, but the user interface restricts this to two [single Upstream and Downstream]) Notes: Upstream section must be present. In the data file, this is stored as the first (of a possible 4) sections Downstream section is optional; if present, this will be used for bridge calculations by default, but may be overridden by the upstream section if the user chooses to, or if absent. In the data file, this is stored as the third (of a possible 4) sections | ||||
Chainage | xp(k,i) | Relative (offset from arbitrary location) cross-chainage coordinate of ith ground cross-section point (m or ft) | Must be in non-decreasing order | |
Elevation | zp(k,i) | Elevation of ith point in ground cross section, above datum (m or ft) | ||
Manning’s n | rn(k,i) | Manning’s n roughness coefficient of ith point in cross section | Value applies between ith and i+1th points | |
Panel | panel(k,i) | Denotes delineation of a panel (horizontal break in conveyance calculation) in section #k | Used for USBPR type only; must appear as [LEFT, RIGHT] pairs over the section, or not at all. Both columns have the same effect, and are included to maintain consistency between BRIDGE and RIVER SECTIONS | |
Marker | chmain(k,i) | Denotes delineation of a panel (horizontal break in conveyance calculation) in section #k | ||
Easting | (easting) | Geographical horizontal coordinate of ith cross-section point | Not used in the computations | |
Northing | (northing) | Geographical vertical coordinate of ith cross-section point | Not used in the computations | |
Bridge length | duall | Total length of the bridge in the direction of flow (i.e. distance between upstream-most face and downstream-most face) | Optional. Only significant in calculations for bridges with separated “carriageways” | |
Skew Angle | skewb | Angle of bridge orientation against normal to flow direction. All data along bridge (underlying cross-section, openings, spill, flood relief culverts) are projected using this angle. Also affects the loss coefficient for USBPR method | Cannot exceed 45° | |
Bridge Section to use for computations | brsec | 2 (“Upstream bridge face” radio button) – use section #2 (upstream bridge section) for bridge computations 3 (“Downstream bridge face” radio button) [default] – use section #3 (downstream bridge section) for bridge computations | Valid values: 2 or 3 only (defaults to 3 otherwise). If set to 3 and d/s data is not entered, then u/s data will be used | |
Openings tab Note: A minimum of one opening must be defined (two for Yarnell type) To add a new row, right-click, use Ctrl-B (insert below), Ctrl-I (insert above) or paste data into the table | ||||
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The following are repeated for each row, where k denotes the row (opening) number, up to a maximum of 25 openings | ||||
Start | x(k,1) | Left springing coordinate (USBPR/ARCH) Left opening coordinate (YARNELL) | ||
Finish | x(k,3) (USBPR/ARCH) x(k,2) (YARNELL) | Right springing coordinate (USBPR/ARCH) Right opening coordinate (YARNELL) | Must be greater than Start | |
Springing Level (USBPR/ARCH) Left Soffit (YARNELL) | z(k,1) | Springing elevation (USBPR/ARCH) Left opening elevation (YARNELL) | ||
Soffit Level (USBPR/ARCH) Right Soffit (YARNELL) | z(k,2) | Soffit elevation (USBPR/ARCH) Right opening elevation (YARNELL) | Soffit level can not be lower than springing level | |
The following two values are written to the network data file for USBPR/ARCH types in order to fully define a parabolic arch shape, but not used in the computations | ||||
(Right springing level; USBPR/ARCH only) | z(k,3) | Springing elevation | Assumed to be the same elevation as left springing | |
(Soffit mid point; USBPR/ARCH only) | x(k,2) | Soffit horizontal coordinate | Not used in computations for – assumed to be the mid-point between left and right | |
Model as dual bridge | n/a | Used to apply an adjustment factor for dual bridges (i.e. bridges with separated carriageways) | Only applies to USBPR/ARCH types | |
Single carriageway width | rdlen | width (in direction of flow) of a single carriageway of a “dual bridge”, i.e. distance between u/s and d/s faces of each constituent ‘bridge’) | Optional. Only to be used for bridges with separated “carriageways”, otherwise must be zero | |
Spill | ||||
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The following four columns must appear, if specified, as a minimum of two rows, up to a maximum of 400 rows (one row per coordinate pair) | ||||
Offset | xsp(i) | Cross-chainage coordinate of ith spill point (m or ft) | Must be in strictly ascending order | |
Spill Elevation | zsp(i) | Elevation coordinate of ith spill point (m or ft above datum) | ||
Easting | (easting) | Geographical horizontal coordinate of ith spill point | Optional. Not used in the computations | |
Northing | (northing) | Geographical vertical coordinate of ith spill point | Optional. Not used in the computations | |
Modular limit | mSpill | Modular limit – ratio of downstream to upstream depth above spill crest at which (partial) drowning initiates | Must be >0, <1 | |
Spill coefficient | cSpill | Spill coefficient, inclusive of discharge coefficient and ✓(2g) term, i.e. 1.7 (3.08 US) for a round-nosed broad-crested weir, etc. | Must be >0 | |
Blockage | ||||
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Blockage proportion | pBlock(1) | Percentage of the bridge opening which is additionally blocked | Must be <100 | |
Blockage description | BlockComment | Free text for modeller to describe the blockage scenario | Optional; not used in computations | |
Inlet loss coefficient | kCont | Contraction loss coefficient, applied as a factor to the velocity head difference at the inlet. | Default 0.5. Can be set to zero (and incorporated into the outlet loss coefficient) | |
Outlet loss coefficient | kExp | Expansion loss coefficient, applied as a factor to the velocity head difference at the outlet. | Default 1.0. Can be set to zero (and incorporated into the inlet loss coefficient) | |
Blockage method | bMethod | Blockage calculation method: Upstream Depth – blockages are calculated using velocities at depth upstream of the bridge Downstream Depth – blockages are calculated using velocities at depth downstream of the bridge Bridge Area – blockages are calculated by reducing the area of the bridge opening by the blockage %age | ||
Relief Culverts | ||||
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The following seven columns may be repeated up to a maximum of 20 rows (one row per flood relief culvert) | ||||
Chainage | xculvert(i) | Cross-chainage coordinate of left edge of ith Flood Relief Culvert (m or ft) | Only used to position the culvert on the plot. Not used in the computations | |
Invert | cinvrt(i) | Invert level of ith flood relief culvert (m/ft AD) | ||
Soffit | csofit(i) | Soffit level of ith flood relief culvert (m/ft AD) | ||
Area | carea(i) | Full wetted area of ith flood relief culvert (m2/ft2) | Shape assumed rectangular | |
Weir discharge coefficient | dispt(i) | Weir discharge/calibration coefficient (multiplicative factor) of ith flood relief culvert | Standard round-nose broad-crested weir equation applies when part-full | |
Orifice calibration coefficient | disful(i) | Orifice discharge/calibration coefficient (multiplicative factor) of ith flood relief culvert | Standard orifice equation applies when full | |
Drowning coefficient | cdrown(i) | Modular limit (for weir flow) of ith flood relief culvert | ||
USBPR Pier Data tab | ||||
This tab is enabled only if bridge type=USBPR; otherwise all data within is ignored | ||||
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Specify Piers / | n/a | Choose to model as Piers (enter number of piers, total width and shapes/coefficent) or not (enter Soffit shape) | ||
Soffit Shape | shape | Shape of soffit, when “Specify soffit shape” is chosen | ‘FLAT’ or ‘ARCH’. Used if Specify Piers is not used [npier=0]. (note alternatives if Specify Piers used) | |
Total Pier width | pierw | Total combined width of all piers | Only used if “Specify Piers” option chosen; and must be > 0 if so | |
Number of Piers | npier | If used, number of piers in line, in the direction of flow; increments the headloss coefficient due to pier effects, for which subsequent pier information is required to be input … | Maximum=3 Must be 1 or more if ‘Specify Piers’ is chosen | |
Pier Shape | shape | Shape of pier, when “Specify Piers” is used | ‘RECTANGLE’, ‘SQUARE’, ‘CYLINDER’, or ‘I-BEAM’ (note alternatives if Specify Piers not used) | |
Pier faces | diaph | Type of pier face, when “Specify Piers” is used | ‘STREAMLINE’, ‘SEMICIRCLE’, ‘TRIANGLE’, or ‘DIAPHRAGM’ | |
Use calibration number | (shape) | Uses an index (0-8) in place of specifying pier shapes | Set shape=’COEFF’ | |
Calibration number | Prcoef | Can use a number instead of pier shapes, if known. Relates to the curves in USBPR 1978 report, Figure 7 (and potential interpolation between). | Used if Specify Piers and “use pier coefficient” are used Range 0-8; can be non-integer | |
Abutment type | iabut | Abutment type: 1: 90 degree wingwall or vertical wall abutment (span < 60m) 2: 30 degree wingwall abutment (span < 60m) 3: everything else (default) | USBPR type only 1, 2 or 3 | |
Abutment alignment | altype | ‘ALIGN’ (default) or other | ||
Parameters tab | ||||
Bridge calibration coefficient | cali | Factor applied to calculated bridge afflux | will be ignored if UNIVERSALC set (and use 1/cdorifice2 instead) | |
use same calibration coefficient for orifice flow and afflux calculations | UniversalC | Use Universal [flow] calibration coefficient. If selected, the orifice calibration coefficient will be applied to the calculated discharge in both afflux and orifice modes. | Since the afflux calibration factor is approximately inversely proportional to the square of the orifice discharge coefficient, then effectively this is equivalent to setting cali to 1/cdorifice2 | |
Model surcharged bridge as orifice flow | oflag | Select this option to transition to orifice flow regime when bridge is surcharged | Will be automatically implemented if bridge contains an integrated spill | |
Lower transition distance | rlower | Depth below soffit at which orifice transition starts | ||
Upper transition distance | rupper | Height above soffit at which fully orifice flow occurs | Must be above lower transition (rlower + rupper > 0) | |
Orifice calibration coefficient | cdorifice | Calibration factor applied to calculated orifice discharge (and bridge discharge if UniversalC set) | only used in orifice mode and/or UNIVERSALC set | |
Transition smoothing factor | tFactor | Controls the degree of “S-shaped” smoothing between bridge afflux and orifice discharge 0 = linear transition (default) For any other value, the higher the value of tFactor, the flatter the ‘S’ is at each end | Default value = 0 (linear). Recommended value (if used: 0.5-2) | |
Yarnell pier coefficient | KYarnell | Yarnell’s pier-shape coefficient | Not to be confused with calibration coefficient | |
Plot | ||||
By default a plot of the bridge, with the following displayed, the bridge area itself being shaded in light grey: • section data • openings • panel markers (if present) • overspill data (if defined) • relief culverts (if defined)
Additionally, the following can be switched on by toggling the checkbox on the plot legend (as well as any of the above being toggled off) • Conveyance • Manning’s n The entire plot display can be toggled on/off via the Various options, including the ability to overlay the cross sections from the RIVER sections immediately upstream and downstream are available from the Options menu. Further, detailed editing, such as changing colours, axes, etc. is available by double-clicking on the plot, via the Edit Chart option on the Options menu or the Alt-D shortcut. Options to copy the image to clipboard, or save as a file, are also available from the main plot menu | ||||
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.Navigating the bridge plot window
On the Bridge Plot, you can use the following actions to zoom in and out:
Action | Effect |
Press Shift and click the diagram. | The mouse pointer changes to |
Press Alt and click the diagram. | The mouse pointer changes to |
Press Shift and select a region on the diagram. | The mouse pointer changes to
A chart is zoomed into the selected region bounds after a user releases the left mouse button. |
Use Ctrl with the + or - key. | A chart’s diagram is zoomed in by 20 percent from the current axis ranges if a user presses and holds the Ctrl key with the + key. A chart’s diagram is zoomed out by 20 percent from the current axis ranges if a user presses and holds the Ctrl key with the - key. |
Use the mouse wheel. | A user should hover a diagram with the mouse pointer and scroll the mouse wheel to zoom in/out by 20 percent from the current ranges of axes. To zoom in/out a chart by an individual axis, they should hover the axis with the mouse pointer and scroll the mouse wheel. |
Use the spread or pinch gestures on a touchscreen device. | Spread or pinch gestures allow a user to zoom in and out a diagram on any touchscreen devices.
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Use Ctrl + Z. | Users should press the Ctrl + Z keys to return the previous zoom state of a diagram. Note that all subsequent operations of a similar kind (for example, multiple “zoom in” operations) are considered as a single transaction. A press of Ctrl + Z returns the zoom state existed before the first zoom operation in a zoom series. |
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You can use the following actions to scroll (pan):
Action | Effect |
Press the left mouse button or wheel button, and drag the mouse pointer. | The mouse pointer changes from
to
after a user holds down the left mouse button. Users should move the mouse pointer with the left mouse button pressed to scroll a diagram in the same direction as the mouse pointer is moved. |
Use axes’ scroll bars. | A user can click a scrollbar arrow or the scrollbar near the thumb, or drag the thumb and move it. |
Use Ctrl + Arrow keys (Left, Up, Right or Down). | A diagram is moved to the left if a user presses Ctrl + Left. A diagram is moved up if a user presses Ctrl + Up. A diagram is moved to the right if a user presses Ctrl + Right. A diagram is moved down if a user presses Ctrl + Down. |
Use flick gestures on a touchscreen device. | Flick gestures allows a user to scroll a diagram on touchscreen devices.
|
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Data file format
Line Data
1 unitType, comment
2 subUnitType
3 Label1, Label2, Label3, Label4
4 RevNo
5 BridgeName
6 Formulation
7 cali, skewb, rdlen, duall, pierw, oflag, rlower, rupper, cdorifice, tFactor
8 iabut
9 npier, shape, diaph, prcoef, KYarnell, UniversalC , brsec
10 altype
11.0 npts(1)
The following line is repeated npts(1) times:
11.i xp(1,i), zp(1,i), rn(1,i), panel(1,i), chmain(1,i), (easting), (northing)
12.0 npts(2)
The following line is repeated npts(2) times (absent if npts(2)=0):
12.i xp(2,i), zp(2,i), rn(2,i), panel(2,i), chmain(2,i), (easting), (northing)
13.0 npts(3)
The following line is repeated npts(3) times (absent if npts(3)=0):
13.i xp(3,i), zp(3,i), rn(3,i), panel(3,i), chmain(3,i), (easting), (northing)
14.0 npts(4)
The following line is repeated npts(4) times (absent if npts(4)=0):
14.i xp(4,i), zp(4,i), rn(4,i), panel(4,i), chmain(4,i), (easting), (northing)
15 OpeningType
16 nOpenings
The following section (nOpenPts(i) and x(I,j,, z(I,j) rows) is repeated nOpenings times
16.i nOpenPts(i)
For each opening, the following line is repeated: twice (in total) for a sloped soffit (Yarnell-type); three times (in total) for a parabolic-shaped soffit (ARCH- or USBPR-type)
16.i.j x(i.j), z(i,j)
17 nculv
The following line is repeated nculv times (in total; absent if nculv=0):
17.i cinvrt(i), csofit(i), carea(i), dispt(i), disful(i), cdrown(i), xCulvert(i)
18 nSpillPts, cSpill, mSpill
The following line is repeated nSpillPts times (in total; absent if nSpillPts=0):
18.i xsp(i), zsp(i), (easting), (northing)
19 BlockComment
20 nBlocks, kCont, kExp, bMethod, Override, tmUnits, REPEAT
The following line only occurs [once] if nBlocks=1 (absent if nBlocks=0; future editions may allow nBlocks>1, i.e. for time-varying blockages):
20.i pBlock(i), t(i), d(i)
Variables in italics are not currently used, but are provided here for potential future use; the meaning of these, and other implied or fixed parameters are as follows:
Name | Meaning / restrictions |
unitType | Fixed text: BRIDGE |
subUnitType | Fixed text: INTEGRATED |
RevNo | Current unit/data file revision number; currently 3 (Flood Modeller v7.3) |
npts(i) | Number of section data points in section #i (i=1-4); must be a minimum of 3 (or zero; though npts(1) can not be zero) |
OpeningType | Soffit shape; currently fixed at PARABOLA1 for ARCH- and USBPR-type; SLOPED for Yarnell-type. Other shapes may be allowed in future editions |
nOpenings | Number of bridge openings; must be at least 1 (at least 2 for Yarnell-type) |
nOpenPts(i) | Number of coordinate pairs to define the soffit: fixed at 3 for PARABOLA1 and 2 for SLOPED |
nCulv | number of flood relief culverts (can be zero, for no flood relief culverts) |
nSpillPts | number of coordinate pairs to define the spill over the bridge top (may be zero, for no spill; otherwise must be at least 2) |
nBlocks | Must be 0 (no blockage modelled) or 1 (blockage modelled). In future editions, may extend to number of blockage-time data sets for time-varying blockages |
Override | Reserved for possible future use – override blockage with value specified in simulation event file |
tmUnits | Reserved for possible future use –time units for time-varying blockages |
REPEAT | Reserved for possible future use – repeat/extend policy for time-varying blockages |
t(i) | Reserved for possible future use – time of time-varying blockage |
d(i) | Reserved for possible future use – date of time-varying blockage |
Data File example
BRIDGE Taken from original design drawings
INTEGRATED
SEV08810 SEV08760
3
Upton Bridge
USBPR
1.000 0.000 0.000 50.000 5.000 ORIFICE 0.000 0.000 1.000 0.000
3
2 CYLINDERSEMICIRCLE 0.000 1.000 3
ALIGNED
53
21.600 13.140 0.035 385219.906240844.203
23.500 12.940 0.035 385218.969240842.547
24.400 12.450 0.035 385218.531240841.750
25.900 12.950 0.035 385217.813240840.453
...
141.500 12.520 0.035 385161.219240739.641
141.500 12.640 0.035 385161.219240739.641
143.500 12.720 0.035 385160.250240737.891
0
53
21.600 13.140 0.035 385219.906240844.203
23.500 12.940 0.035 385218.969240842.547
24.400 12.450 0.035 385218.531240841.750
...
141.500 12.520 0.035 385161.219240739.641
141.500 12.640 0.035 385161.219240739.641
143.500 12.720 0.035 385160.250240737.891
0
PARABOLA1
2
3
68.000 11.200
77.500 11.600
87.000 11.200
3
97.000 11.200
106.500 11.600
116.000 11.200
1
10.200 11.200 2.000 1.000 1.000 0.900 64.000
24 1.700 0.900
34.000 12.800 0.000 0.000
39.000 12.936 0.000 0.000
...
134.000 12.812 0.000 0.000
139.000 12.663 0.000 0.000
141.000 12.600 0.000 0.000
25% blockage scenario
1 0.500 1.000 USDEPTH
25