1D Culverts: Difference between revisions
Content deleted Content added
Rohan.king (talk | contribs) |
No edit summary |
||
| (22 intermediate revisions by 5 users not shown) | |||
Line 1:
<br>▼
<br>▼
=Introduction=
A culvert is a structure that allows water to flow under a road, embankment, railway or other similar obstruction from one side to the other. Culverts or pipe channels can be either rectangular, circular (pipe) or irregular in shape and can vary in size depending on the flow and design requirements.
<br>
=1D-2D Connections=
Line 18 ⟶ 8:
*Manually assigned 2D SX connections
Information on how to create a 1D-2D connection in a GIS package are explained within <u>[[
===SX Connection Hints===
To limit the doubling up of expansion and contraction losses on a culvert (as 1D nwke culverts will already contain height, width, entry and exit coefficients) the 2D flow into and out of a culvert should be as representative of the culvert dimensions. You can achieve this by selecting the number of 2D cells that best matches the width/diameter of your particular culvert. The example below shows a 4m culvert that has used an SX line to select 2 x 2m grid cells to discharge to. Remember that the selection of a particular cell, when using a polyline, requires the polyline intersect the cell cross-hair -
[[File:Culvert_SX_connection_1.JPG|border|500px]]
<br>
Line 46 ⟶ 36:
=Flow Regimes=
The flow regime through a culvert are divided into the following types. Checking this information for any 1D culvert can be inspected from the _TSF.mif/_TSF_P.shp that outputs the regime at each output interval. <br>
{| align="left" class="wikitable
! style="background-color:#005581; font-weight:bold; color:white;"| Regime
Line 74 ⟶ 64:
|}
▲<br>
'''Example of the _TSF results in GIS:'''<br>
[[File:TSF_result_file.JPG|border|600px]]
Line 81 ⟶ 70:
The GIS results for the _TSF layer show the flow regime that was recorded at each output interval.
=Modelling Bend Losses=
Where bends occur within one culverted length, additional losses can be applied using the form_loss attribute of the 1d_nwk layer. This applies the energy loss appropriately for a 'minor' loss using K*V<sup>2</sup>/2g. Bend loss coefficients (K) are found in many standard hydraulic references, e.g.:
=Typical check files used=▼
The table below highlights some of the commonly used check files when reviewing 1D culverts. The full list of TUFLOW check files can be found [[TUFLOW_Check_Files | here]]. <br>▼
:*<u>[https://www.business.qld.gov.au/industries/mining-energy-water/water/industry-infrastructure/supply-planning/urban-stormwater-drainage Queensland Urban Drainage Manual]</u>
:*<u>[https://www.ciria.org/CIRIA/Item_Detail.aspx?WebsiteKey=3f18c87a-d62b-4eca-8ef4-9b09309c1c91&iProductCode=C689F&Category=FREEPUBS&OrderLineId=71a52fd5-34ac-4bd9-b219-e1c97a45e059 Culvert Design and Operation Guide (C689F)]</u>
:*<u>[https://www.fhwa.dot.gov/engineering/hydraulics/pubs/12026/hif12026.pdf Hydraulic Design of Highway Culverts]</u>
▲The table below highlights some of the commonly used check files when reviewing 1D culverts. Although this list may not be all the check file you could use to review 1D culverts it is certainly a good starting point. The full list of TUFLOW check files can be found <u>[[TUFLOW_Check_Files | here]]</u>. <br>
{| align="left" class="wikitable" width="20%"
Line 92 ⟶ 87:
! style="background-color:#005581; font-weight:bold; color:white;"| Filename prefix / suffix
|-
| [[Check_Files_1d_inverts | _inverts_check.mif<br>_inverts_check_P.shp]]
|-
| [[Check_Files_1d_IWL | _iwl_check.mif<br>_iwl_check_P.shp]]
|-
| [[Check_Files_1d_nwk_C | _nwk_C_check.mif<br>_nwk_C_check_L.shp]]
|-
| [[Check_Files_1d_nwk_N | _nwk_N_check.mif<br>_nwk_N_check_P.shp]]
|}
<br><br><br><br><br><br><br><br><br>
<br>
<br>
Any further questions please email TUFLOW support: [mailto:support@tuflow.com?Subject=TUFLOW%201D%20culverts%20help support@tuflow.com]
▲<br><br>
{{Tips Navigation
|uplink=[[ TUFLOW 1D Channels and Hydraulic Structures | Back to 1D Channels and Hydraulic Structures]]
}}
| |||