I. Deska, M. Mrowiec, E. Ociepa
Technical University of Czestochowa, Faculty of Infrastructure and Environment, Institute of Environmental Engineering, Częstochowa, PL

INFLUENCE OF THE HYDROGEL ADDITION ARRANGEMENT IN THE SUBSTRATE ON THE RETENTION CAPACITY OF GREEN ROOFS


In urbanized areas, in addition to the traditional sewer systems, increasingly are used the sustainable urban drainage systems (SUDS), inter alia, the green roofs. The article presents the results of research of retention capacities of 4 green roof models. In these models were used: in model 1 – the typical extensive substrate, in models 2 and 3 – the above-mentioned extensive substrate with addition of hydrogel (cross-linked polyacrylate potassium), in model 4 – agrotextile inserts with hydrogel. Model 2 additionally contained the plants (Goldmoss Stonecrop Sedum Acre). Models 2, 3 and 4 contained the same portion of hydrogel (30 g). The field experiments were conducted in two stages under natural atmospheric conditions. The initial stage included the first simulated precipitation (all layers of green roof models were air-dry during these experiments). The second stage included the further investigations of the retention capacities of green roof models, predominantly with use of natural precipitations. The obtained results of initial stage of experiments show that during the first simulated precipitation the best retention capacities had models 2 and 3 (with hydrogel admixtures). The least amount of water was absorbed by model 1 (without hydrogel additive) and model 4 (containing agrotextile inserts with hydrogel). The results of second stage of experiments show that during further natural precipitations the best retention capacities had model 2, with plants and substrate containing hydrogel admixture. Amongst models containing hydrogel additives, the least retention capacity had model 4, with substrate containing agrotextile inserts with hydrogel.

Keywords: green roof, retention capacity, stormwater management, substrate, hydrogel