Development of a Laboratory Method for the Comparison of Settling Processes of Road-Deposited Sediments with Artificial Test Material

Solids dynamics in gully pots

“…Sansalone et al (1998) reported 350< D 50 < 800 µm, Pratt and Adams (1984) a D 50 of approximately 680 µm, and Ellis and Harrop (1984) 600< D 50 < 1000 µm. Gelhardt, Huber, and Welker (2017) reported ρ of approximately 2500 kg/m 3 and Naves et al (2020) of approximately 2600 kg/m 3 for street solids. To avoid health hazards and for practical reasons, it was decided to use clean sand (ρ approximately 2650 kg/m 3 ) to mimic real street solids in the experiments.…”

Settling of Road-Deposited Sediment: Influence of Particle Density, Shape, Low Temperatures, and Deicing Salt

“…As these results partly differ from the results of Rommel and Helmreich [9] and the investigation was done with the model of a hydrodynamic separator and not a basic sedimentation unit, the settling column experiments proposed by Gelhardt et al [17] were adapted to further evaluate the effects of particle density, shape, temperature, and deicing salt (sodium chloride, NaCl) concentration. Based on these results, the model proposed by Rommel and Helmreich [9] was further developed to be able to model settling experiments and was consecutively validated.…”

“…However, previous studies have shown that SCMs exhibit reduced retention efficiency under winter conditions caused by low temperature and deicing salts [9][10][11]. To design the sedimentation stages of SQIDs, knowledge about particle characteristics and settling velocity distributions of RDSs is crucial [12,13], especially to separate fine particles and particles with low density, which show an increased contaminant load [5,[14][15][16][17]. In addition, the influence on settling by particle size distribution (PSD), particle density, and runoff event-specific properties, such as first flush and runoff volume and intensity, has been comprehensively studied [18][19][20][21][22][23].…”

“…There are various protocols to determine settling velocity distribution [12,17,[26][27][28]; however, they have not been utilized yet to quantify the influence of temperature and deicing salts on the settling velocity of RDSs. Commonly, artificial test materials are used to reduce variations of PM properties [17]. Gelhardt et al [17] developed a laboratory method to measure and compare the settling behavior of artificial and real particle collectives with a reproducible PSD.…”

“…Commonly, artificial test materials are used to reduce variations of PM properties [17]. Gelhardt et al [17] developed a laboratory method to measure and compare the settling behavior of artificial and real particle collectives with a reproducible PSD. Real RDSs were used in the study, yet the focus was on method development and not on the influence of boundary conditions on the settling behavior of RDS.…”