What is bank lines in HEC-RAS?
Bank Lines are used to define the main channel banks for a cross section. If the bank lines are not defined, the bank stations will be set to the ends of the cross sections.
What are Bank stations?
Bank and Monument are interlinked London Underground and Docklands Light Railway stations that form a public transport complex spanning the length of King William Street in the City of London.
What are main channel bank stations?
Main Channel Bank Stations. The main channel bank stations are used to define what portion of the cross section is considered the main channel and what is considered left and right overbank area. The bank stations must correspond to stations entered on the cross section X & Y coordinates table.
How do I change my bank station in Ras Mapper?
One of the best tools for editing cross-sections in HEC-RAS is the graphical cross-section editor. In the geometric editor, go to Tools >> Graphical Cross-Section Edit. You can use the editor to move bank stations, change the distribution of Manning’s n, add/move/delete ground points, edit structure, etc.
What is flow path in HEC-RAS?
Flow Path lines are used to compute reach lengths between cross sections in the left and right overbank. Lines will be created in the overbank areas based on on 1/3 of the distance from the bank stations to the ends of the cross section and will be shaped based on the river. …
Are HEC-RAS cross sections looking upstream or downstream?
Each cross section in a HEC‑RAS model is identified by a river, reach, and river station. Cross section data are traditionally defined looking in the downstream direction. The program considers the left side of the stream to have the lowest station numbers and the right side to have the highest.
What exit is bank station?
The Bank station is the nearest one to Bank Station, Exit 6 in City Of London.
What is downstream reach lengths HEC RAS?
The downstream reach lengths of the channel define the distance to the next downstream cross section measured along the stream. The downstream reach lengths of the overbanks define the distance to the next downstream cross section measured along the path of the center of mass for the overbank flow.
What is reach in HEC RAS?
The measured distances between cross sections are referred to as reach lengths. The reach lengths for the left overbank, right overbank and channel are specified on the cross section data editor. Channel reach lengths are typically measured along the thalweg.
What is Ras Mapper?
HEC-RAS Mapper can be used to develop terrain models and visualize HEC-RAS results in a map-based format. Computed model results can be displayed dynamically on the fly, or they can be written to a static (stored to disk) map layer/depth grid file. …
How do I change terrain in HEC-RAS?
There are currently two methods for improving channel data in HEC-RAS: (1) using cross sections to create an interpolation surface to add to an existing terrain model; (2) using the vector Terrain Modification tools in RAS Mapper to improve the terrain by adding channel information, adding high ground (such as a road).
Does HEC-RAS looking upstream or downstream?
The numbering system must be consistent in that HEC‑RAS assumes that higher river stations are upstream and lower river stations are downstream. Each data point in the cross section geometry is given a station number corresponding to the horizontal distance from a starting point on the left.
How are Bank stations placed in a HEC-RAS?
Changes in main channel width should generally be gradual from one cross section to the next. One of the most basic steps in constructing your HEC-RAS model is to go through every cross section and properly place bank stations.
How does the HEC-RAS model calculate WSE?
HEC-RAS is a one-dimensional model and divides the flow into left overbank, channel, and right overbank flow areas. It computes a friction value for each of the three, distributes the water to get equivalent WSE (IIRC) and then outputs a WSE for the cross-section.
Where are the Bank stations in a cross section?
Here’s an example of a simple cross section with properly placed bank stations: Notice the bank stations (the red dots on the plot) also reside at the grade break between the physical channel and the flatter overbanks.
How are cross section properties updated in Ras?
Cross section properties will continue to be updated each time a cross section cut line is edited. Therefore, the river station value will be updated as you edit the cross section layout, each time you finish editing the feature (close it). This may break linkages with other RAS data that depends on the river station.