Vol.:(0123456789) https://doi.org/10.1007/s11269-021-03044-6 1 3 Riprap Effect on Hydraulic Fracturing Process of Cohesive and Non‑cohesive Protective Levees Javad Ahadiyan 1  · Farhad Bahmanpouri 2  · Atefeh Adeli 3  · Carlo Gualtieri 4  · Alireza Khoshkonesh 5 Received: 22 March 2021 / Accepted: 10 December 2021 © The Author(s), under exclusive licence to Springer Nature B.V. 2021 Abstract A comprehensive experimental study was conducted to evaluate the efects of soil proper- ties and the rip-rap as well as cohesive and non-cohesive soil material and the riprap particle size on the breaching process and the failure mechanism of the levee. The results showed the crucial role of the riprap coverage and the soil properties in the breaching of the protective levees. In this regard, breaching was developed in both vertical and transverse directions. In the levee without riprap coverage, breach development was observed in the transverse direc- tion while the levee was eroded in the streamwise direction. In contrast, in the levee with riprap coverage, breach development mainly occurred in the vertical direction. Furthermore, the fow rate across the breach was higher in the tests with no riprap compared to those with the riprap coverage. Comparisons suggested that the shorter the failure time, the longer the equilibrium time. The present research has some major implications for coastal and hydrau- lic engineering designs since the construction of levees is of great importance. Furthermore, the fndings can be used to predict fooding and erosion induced by the embankment failure. Keywords Protective levees · Non-cohesive levee · Cohesive levee · Riprap · Erosion 1 Introduction Catastrophic foods could cause extensive economic, social, and environmental damage. In this regard, levees are constructed to prevent seasonal foods and confne the river food fow, resulting in a higher and more rapid fow (Sills et al. 2008; Bahmanpouri * Farhad Bahmanpouri farhad.bahmanpouri@irpi.cnr.it 1 Water Engineering and Environmental Faculty, Shahid Chamran University of Ahvaz (SCU), 61357-83151 Ahvaz, Iran 2 Hydraulic Engineering, IRPI-CNR (Consiglio Nazionale Delle Ricerche), Via Madonna Alta 126, 06128 Perugia, Italy 3 Hydraulic Structures at Shahid, Chamran University of Ahvaz (SCU), 61357-83151 Ahvaz, Iran 4 Department of Structures for Engineering and Architecture, University of Napoli Federico II, University of Napoli Federico II, 80125 Napoli, Italy 5 Water Structures, Department of Water Engineering, Bu-Ali Sina University, 65178 Hamedan, Iran /Published online: 17 January 2022 Water Resources Management (2022) 36:625 639 –