The program FRACHT allows the measurement of storm water discharge in combined sewerage system after ATV-Arbeitsblatt A 128. It will design the storm water tank retaining the first flush of storm water, tank with overflow for settled combined sewage and sewer with storage capacity and overflow.
Basics of design
Based on the simplified calculation by distributing the total volume into individual buildings after ATV-Arbeitsblatt A 128 since April 1992.
For the COD values CR (107 mg/l) and CK (70mg/l) in the ATV-Arbeitsblatt A 128, constant sizes are mentioned. These values are used for the calculation in FRACHT.
The basin data are arranged under (alphanumeric) basin designation. The sequence during the input of the individual buildings is optional. FRACHT sorts the entered reservoir network before the hydraulic calculation.
The formulae in the program adopted from the standard design guidelines.
Sewer with storage capacity & overflow channels with low discharge take a privileged position in the computation because of the 50 % of volume addition. By special labelling of such 'Basins', during the data collection, this addition is considered automatically during the basin calculation.
During the calculation of the reservoir volumes, all limit values specified in the guideline are considered. If the threshold value of the rainfall-runoff is exceeded, then it is marked in the result.
Special arrangements for Bayern and/or Rheinland-Pfalz can be considered optionally.
Data output
The resulting data output is in the tabular form.
| • | Computation result including input data in a long form (1 side/basin) |
| • | Computation result in short form (1 line/basin) |
Application limitations
Max. 100 Storm water overflow structures