User Forum of Software BASEMENT / Sediment Transport

Transport capacity

dummy@example.com (Stefano) — Wed, 14 Jan 2026 17:02:58 +0000

Dear Basement community,

I'd like to understand the meaning of thid statement about "capacity transport" in GUI help: [...]
It is also possible to specify a time series with the inflowing sediment volume [m3/s], which then is distributed on the grain fractions according to the calculated transport capacities [...].
Time series stands for "sedimentograph"? in such a case if I insert "file" item, a warning inform me that it will not be used!
Please, someone could explain me how can I add sediment from upward watershed basin into my domain other that "sediment discharge" (giving big problems)?
Thanks.

Gravitational transport

dummy@example.com (Stefano) — Tue, 08 Oct 2024 10:56:40 +0000

Hi Lukas,

thank you so much for your kind response.
Excuse me to be in late by I needed to apply and verify your suggestions before writing.
I think I've detected the real cause of my problems: lateral friction along stream banks, 'cos I'm working on a mountain stream flushing between two steep - but not vertical - stone walls.
It seems that sediment stard depositing on face wall, rapidly increasing both vertically and laterally: after a while it forms a kind of earth dam across the entire stream section.
So I activated gravitational transport even for stream bank (via MATID) and now simulation seems to progress reasonably, at least.

Again, many thanks to you

cheers, Stefano

deltaz vs sediment sum

dummy@example.com (Stefano) — Wed, 11 Sep 2024 09:15:11 +0000

Hi to you all,

I really cannot understand the difference between the two items in the morphological block.
Please, can anyone kindly explain me the conceptual and practical difference, even with a simple esample?
Thanks, cheers.

Cross section

dummy@example.com (Stefano) — Tue, 23 Jul 2024 11:06:42 +0000

Hi Matthias,
thanks for your reply, though I'm on late.

Exterior bank erosion in a 180° bend due to curvature effect

dummy@example.com (Matthias Bürgler) — Wed, 12 Jun 2024 09:06:36 +0000

Hi Jakob,

We have a very similar test case to test the capability of BASEMENT to reproduce the point bars occuring in such bends.

For the BASEHPC (previously BASEMENTv3), such a test case was featured in the most recent publication (see Test T4 in the Results section), which is freely available here:

https://www.sciencedirect.com/science/a … 4815221001

The same test case was also used in the PhD thesis of Vonwiller (2018) with BASEMD and the results were in good agreement with experiments (see Section 8.2). The thesis freely available here: https://www.research-collection.ethz.ch … /1/246.pdf

I recently tried to reproduce this test case with BASEMD and got reasonable results. Here is the model.json for that test:

{
  "SETUP": {
    "BASEMD": {
      "multiregion": "struiksma",
      "BASEPLANE_2D": [
        {
          "GEOMETRY": {
            "file": "Uchannel_coarse.2dm",
            "type": "2dm",
            "STRINGDEF": [
              {
                "name": "inflow",
                "node_ids": [
                  4,
                  6316,
                  6304,
                  6257,
                  6456,
                  6261,
                  6459,
                  5083,
                  6245,
                  6243,
                  6254,
                  6220,
                  6233,
                  6237,
                  5
                ],
                "upstream_direction": "right"
              },
              {
                "name": "outflow",
                "node_ids": [
                  122,
                  6184,
                  6447,
                  6167,
                  6169,
                  6445,
                  6063,
                  6179,
                  6174,
                  6193,
                  6137,
                  6189,
                  6138,
                  123
                ],
                "upstream_direction": "left"
              }
            ]
          },
          "HYDRAULICS": {
            "FRICTION": {
              "default_friction": 0.01,
              "grain_size_friction": "no",
              "type": "chezy",
              "wall_friction": "off"
            },
            "INITIAL": {
              "type": "continue",
              "file": "../../initMor/run/struiksma_flume_restart.h5",
              "restart_solution_time": -1.0
            },
            "PARAMETER": {
              "dynamic_depth_solver": "on",
              "dynamic_depth_solver_precision": 0.005,
              "geo_max_angle_quadrilateral": 45,
              "geo_min_area_ratio": 0.05,
              "geo_min_aspect_ratio": 0.06,
              "minimum_water_depth": 0.001,
              "riemann_solver": "exact",
              "riemann_tolerance": 1e-06,
              "simulation_scheme": "exp",
              "velocity_update_partial": "volume_area"
            },
            "BOUNDARY": [
              {
                "type": "hydrograph",
                "number_of_iterations": 5000,
                "precision": 0.1,
                "string_name": "inflow",
                "file": "inflow.txt",
                "slope": 2,
                "dynamic_slope": "no",
                "max_interval": 20,
                "weighting_type": "area",
                "wse_calc_method": "average"
              },
              {
                "type": "hqrelation",
                "string_name": "outflow",
                "slope": 2,
                "conveyance_type": "tables",
                "dynamic_slope": "no",
                "wall_flux": "no",
                "weighting_type": "area",
                "wse_calc_method": "average"
              }
            ]
          },
          "OUTPUT": {
            "console_time_step": 100.0,
            "restart_time_step": 1e+32,
            "SPECIAL_OUTPUT": [
              {
                "output_time_step": 10.0,
                "threshold_wse": -1000000.0,
                "type": "boundary_history",
                "boundary_values": [
                  {
                    "accumulator": "none",
                    "value": "Q"
                  },
                  {
                    "accumulator": "none",
                    "value": "Qsed"
                  },
                  {
                    "accumulator": "integrate",
                    "value": "Qsed"
                  }
                ],
                "flush_all_num_steps": 0,
                "history_one_file": "yes"
              },
              {
                "output_time_step": 100.0,
                "threshold_wse": -1000000,
                "type": "element_centered",
                "format": "vtk",
                "values": [
                  {
                    "accumulator": "none",
                    "value": "wse"
                  },
                  {
                    "accumulator": "none",
                    "value": "velocity"
                  },
                  {
                    "accumulator": "none",
                    "value": "z_element"
                  },
                  {
                    "accumulator": "none",
                    "value": "tau"
                  },
                  {
                    "accumulator": "none",
                    "value": "grain_size"
                  },
                  {
                    "accumulator": "none",
                    "value": "depth"
                  },
                  {
                    "accumulator": "none",
                    "value": "bedload_vec"
                  }
                ],
                "split_file": "no"
              }
            ]
          },
          "TIMESTEP": {
            "CFL": 0.9,
            "ignore_wave_celerity": "off",
            "initial_time_step": 0.001,
            "maximum_time_step": 100,
            "minimum_time_step": 0.001,
            "morph_cycle": "off",
            "start_time": 0.0,
            "total_run_time": 24000.1
          },
          "region_name": "ribberink_flume",
          "MORPHOLOGY": {
            "BEDMATERIAL": {
              "GRAIN_CLASS": {
                "diameters": [
                  1
                ]
              },
              "MIXTURE": [
                {
                  "name": "mixture1",
                  "volume_fraction": [
                    100
                  ]
                }
              ],
              "SOIL_ASSIGNMENT": {
                "index": [
                  1
                ],
                "soil": [
                  "soil1"
                ],
                "type": "index_table"
              },
              "SOIL_DEF": [
                {
                  "name": "soil1",
                  "tau_erosion_start": -1,
                  "LAYER": [
                    {
                      "bottom_elevation": -5.0,
                      "mixture": "mixture1"
                    }
                  ]
                }
              ]
            },
            "INITIAL": {
              "type": "initial_mesh"
            },
            "PARAMETER": {
              "control_volume_initial": "soildef",
              "control_volume_type": "constant",
              "create_new_layers": "off",
              "density": 2650,
              "distortion_offset": 0,
              "distortion_time_interval": -1,
              "local_slope_angle_repose": 30,
              "min_theta_critic": 0.02,
              "porosity": 40.0,
              "strong_coupling": "off",
              "control_volume_thickness": [
                0.0097
              ],
              "control_volume_thickness_index": [
                1
              ]
            },
            "BEDLOAD": {
              "FORMULA": {
                "bedforms_type": "no_bedforms",
                "bedload_factor": 0.5,
                "bedload_formula": "mpm",
                "local_slope_correction": "no_local_slope",
                "bedload_exponent": 1.5,
                "theta_critical": [
                  0.047
                ],
                "critical_shear_stress_calibration": 1.0,
                "theta_critical_approach": "theta_critical_vanrijn",
                "theta_critical_hiding": "mean",
                "theta_critical_index": [
                  1
                ]
              },
              "PARAMETER": {
                "bedload_routing_start": 0,
                "limit_bedload_wetted": "on",
                "use_cell_averaged_bedload_flux": "off",
                "use_real_edge_lengths": "off"
              },
              "BOUNDARY": [
                {
                  "string_name": "inflow",
                  "type": "IOUp",
                  "mixture": "mixture1",
                  "name": "inflow_sed",
                  "fraction_boundary": 1.0
                },
                {
                  "string_name": "outflow",
                  "type": "IODown",
                  "name": "outflow_sed",
                  "fraction_boundary": 1.0
                }
              ],
              "DIRECTION": [
                {
                  "lateral_index": [
                    1
                  ],
                  "lateral_transport_type": "lateral_bed_slope",
                  "lateral_transport_factor": 1.4,
                  "lateral_transport_exponent": 0.5,
                  "scale_lateral_transport": "yes"
                },
                {
                  "lateral_index": [
                    1
                  ],
                  "lateral_transport_type": "curvature_effect_dynamic",
                  "curvature_transport_factor_type": "fix",
                  "curvature_transport_factor": 11.0,
                  "update_timestep_radius": 10.0,
                  "initial_radius": 10000.0,
                  "min_abs_radius": 2.0,
                  "min_abs_radius_use": "significance_value",
                  "radius_calculation_type": "velocity_vectors"
                }
              ]
            }
          }
        }
      ]
    },
    "simulation_name": "struiksma_test_v28"
  }
}

Error in mass balance of Controlsections and total change of volume

dummy@example.com (Matthias Bürgler) — Wed, 12 Jun 2024 08:46:52 +0000

Hi Jakob,

Did you figure this out or is this is an open issue?

Best regards,
Matthias

sediment transport balancing in crosssections and boundaries

dummy@example.com (Matthias Bürgler) — Wed, 12 Jun 2024 07:54:27 +0000

Hi Fabian,

I am not sure if this is still of interest for you, but I could have a look if you provide a small test case that reproduces the problem.

Best regards,
Matthias

"Exception" problem with sediment transport

dummy@example.com (nicolagroff) — Wed, 30 Mar 2022 08:27:30 +0000

Hi Lukas,

It works!

Thank you very much!

Have a nice day

Nicola

Wu formula - slope

dummy@example.com (Lukas Vonwiller) — Tue, 22 Mar 2022 15:05:17 +0000

Hi Irene

The local slope correction is applied on the critical Shields parameter for each grain fraction (theta_cr,g). However, I am not sure if the local slope correction makes a lot of sense in combination with the Wu formula, test this carefully! I would recommend using the local slope correction more for formulas like mpm_mulit or mpmh.

Hope this helps!
cheers, Lukas

No deltaz over a weir

dummy@example.com (Matteo Facchini) — Fri, 19 Nov 2021 08:47:46 +0000

I am not quite sure what is happening, I see from your results that you have high velocity values over the weir, but no erosion whatsoever.

I would do some tests:

remove the turbulence model
use the IOUp upstream boundary condition for sediment transport and remove the gravitational transport

Cheers
Matteo

external source of sediment and large deposition

dummy@example.com (Matteo Facchini) — Mon, 25 Oct 2021 09:11:42 +0000

You can try and add the gravitational transport in the cells where you set your source.
Cheers
Matteo

Set different grain class and apparent cohesion along the vertical

dummy@example.com (Matteo Facchini) — Fri, 24 Sep 2021 08:43:01 +0000

Hi Alessandro,

you can do multigrain simulations with basement 2.8, not with basement 3.1.1. There is a simple approach described in the tutorials for basement 2.8 (Flaz 2D multigrain).

As to basebreach, it depends on what you need to simulate and how you want to describe the process.

Best
Matteo

Unreal deposition at the inlet of the mesh

dummy@example.com (Matteo Facchini) — Tue, 24 Aug 2021 09:49:06 +0000

Hi Lorenzo,

I strongly suggest you to look in the forum before posting new issues.

The problem you are facing has already been discussed by other users:

I had the same exact problem as you have and both approaches proposed in this topic solved it
Same problem, but for inner boundary condition type gate
Same problem, but for inner boundary condition type weir
Another approach
A solution similar to mine (see item n. 1 in this list)

I hope this helps!
Matteo

Pollutant transport

dummy@example.com (RobertoP) — Mon, 07 Jun 2021 11:31:00 +0000

Dear all,
can anybody tell me if Baseplane v.2.8 can simulate pollutant transport?
I'm not able to find some guidelines for the creation of the Basement input file.
Regards,

Roberto

Run error of sediment transport

dummy@example.com (Matteo Facchini) — Tue, 18 May 2021 07:13:06 +0000

Yes, the triangles (mesh elements) on the upstream boundary