The Experts below are selected from a list of 18525 Experts worldwide ranked by ideXlab platform
Michele Palermo - One of the best experts on this subject based on the ideXlab platform.
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3d plunge pool Scour with protection measures
Journal of Hydro-environment Research, 2010Co-Authors: Stefano Pagliara, Dipankar Roy, Michele PalermoAbstract:Abstract Plunge pool Scour phenomena are well-known for destructive action at the base of hydraulic structures. An experimental study was conducted at the Hydraulic Laboratory of the University of Pisa, Italy, to investigate the hydraulics of 3D plunge pool Scour in presence of simple protection measures. The main geometrical Scour hole parameters were investigated and various relationships are proposed for different flow conditions. These parameters include the maximum dynamic Scour hole depth, the maximum Scour hole width and the location of the Scour hole initiation point. Equations for all these parameters are presented in terms of the basic Scour variables including the jet densimetric Froude number, jet impact angle, tailwater elevation above the originally horizontal sediment bed level and the protection permeability and longitudinal positions of the protection. Moreover, a Scour hole typology and relationships for the non-dimensional longitudinal Scour hole profile in presence of the protection are also given.
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plane plunge pool Scour with protection structures
Journal of Hydro-environment Research, 2008Co-Authors: Stefano Pagliara, Michele PalermoAbstract:Abstract Plunge pool Scour is an important research topic in hydraulic engineering. An experimental study was carried out at the Hydraulic laboratory of the University of Pisa (Italy) to understand the hydraulics of plane plunge pool Scour in presence of basin protection structures. It is known that the Scour hole due to the jet impact depends on several parameters (i.e. jet discharge, jet angle, tailwater, densimetric Froude number and granulometric properties of the basin material); in presence of structures other parameters are involved, such as permeability and geometrical location of the protection structure. More than 400 experiments were carried out in order to develop relations that predict different geometrical parameters of the Scour hole: the maximum Scour depth, the Scour length and the dynamic Scour volume.
Stefano Pagliara - One of the best experts on this subject based on the ideXlab platform.
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Scour of clear water rock w weirs in straight rivers
Journal of Hydraulic Engineering, 2014Co-Authors: Stefano Pagliara, Sahameddin Mahmoudi Kurdistani, Liborio CammarataAbstract:AbstractScour characteristics downstream of rock W-weir structures were studied in a horizontal straight channel and under clear water conditions. For each structure, different hydraulic conditions were considered, including densimetric Froude numbers, water drops, and tailwaters. Results showed that the tailwater depth plays an important role in predicting the Scour parameters. Dimensional analysis was used to derive equations to predict the maximum Scour depth and length and the maximum dune height and length. Selected tests were conducted with an open W-weir. In this case, results show that the maximum Scour depth decreases and its location shifts downstream with respect to classical W-weirs. Three types of Scour morphology were classified: Type A, characterized by one Scour hole and two ridges; Type B, with two Scour holes and two ridges; and Type C, characterized by only one Scour hole and one ridge.
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3d plunge pool Scour with protection measures
Journal of Hydro-environment Research, 2010Co-Authors: Stefano Pagliara, Dipankar Roy, Michele PalermoAbstract:Abstract Plunge pool Scour phenomena are well-known for destructive action at the base of hydraulic structures. An experimental study was conducted at the Hydraulic Laboratory of the University of Pisa, Italy, to investigate the hydraulics of 3D plunge pool Scour in presence of simple protection measures. The main geometrical Scour hole parameters were investigated and various relationships are proposed for different flow conditions. These parameters include the maximum dynamic Scour hole depth, the maximum Scour hole width and the location of the Scour hole initiation point. Equations for all these parameters are presented in terms of the basic Scour variables including the jet densimetric Froude number, jet impact angle, tailwater elevation above the originally horizontal sediment bed level and the protection permeability and longitudinal positions of the protection. Moreover, a Scour hole typology and relationships for the non-dimensional longitudinal Scour hole profile in presence of the protection are also given.
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plane plunge pool Scour with protection structures
Journal of Hydro-environment Research, 2008Co-Authors: Stefano Pagliara, Michele PalermoAbstract:Abstract Plunge pool Scour is an important research topic in hydraulic engineering. An experimental study was carried out at the Hydraulic laboratory of the University of Pisa (Italy) to understand the hydraulics of plane plunge pool Scour in presence of basin protection structures. It is known that the Scour hole due to the jet impact depends on several parameters (i.e. jet discharge, jet angle, tailwater, densimetric Froude number and granulometric properties of the basin material); in presence of structures other parameters are involved, such as permeability and geometrical location of the protection structure. More than 400 experiments were carried out in order to develop relations that predict different geometrical parameters of the Scour hole: the maximum Scour depth, the Scour length and the dynamic Scour volume.
Xiong Yu - One of the best experts on this subject based on the ideXlab platform.
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time domain reflectometry automatic bridge Scour measurement system principles and potentials
Structural Health Monitoring-an International Journal, 2009Co-Authors: Xinbao Yu, Xiong YuAbstract:Bridge Scour is a major factor contributing to the failures of highway bridges constructed over waterways. During flood events, sediments can be washed away and bridge substructures (piers and abutments) are left inadequately supported. Field monitoring of bridge sour process is necessary to study the Scour mechanism, to develop Scour-resistant design of bridge piers and abutments, to implement effective Scour countermeasures, and to deploy safety warning systems. The current instruments are not completely satisfactory in providing real-time monitoring data during critical flood events. This study introduces the development of an automatic Scour monitoring system using time domain reflectometry (TDR) principle. It presents the principles and system design of the TDR sediment Scour monitoring system. An analyses algorithm for Scour signals has been developed. It was found to be robust and can be implemented to automate Scour signal interpretation. Simulated experiments were conducted to validate the perfor...
Joon Huang Chuah - One of the best experts on this subject based on the ideXlab platform.
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Empirical model for Darrieus-type tidal current turbine induced seabed Scour
Energy Conversion and Management, 2018Co-Authors: Chong Sun, Wei-haur Lam, Yonggang Cui, Tianming Zhang, Jiang Jinxin, Guo Jianhua, Ma Yanbo, Wang Shuguang, Teng Hwang Tan, Joon Huang ChuahAbstract:Abstract Tidal current turbine has attracted many attentions, but the impact of Darrieus-type tidal current turbine on the seabed Scour process still remains unclear. This work aims to propose an empirical model, which can be used to predict the maximum Scour depth against different tip clearance and rotor radius. The study also presents the Scour profiles along centreline of turbine by using the proposed empirical equations. A series of three-dimensional printed turbine models were placed in a circulating water flume to investigate the Scour profiles. The results suggest that the Scour depth increases with the decrease of tip clearance. When the turbine is installed very close to seabed, the Scour process is live bed Scour with the collapse of the slant bed. Under this kind of condition, the maximum Scour depth will not further increase with the continuous decrease of tip clearance. The current experimental results propose that the maximum Scour depth is about 80% deeper than Scour depth around single pile. The maximum Scour depth increases firstly and then decreases with the increase of rotor radius. Based on experimental results, an empirical model of Darrieus-type tidal current turbine induced seabed Scour is proposed to predict the maximum Scour depth and Scour profiles along centreline of turbine.
Francesco Laio - One of the best experts on this subject based on the ideXlab platform.
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a framework for probabilistic assessment of clear water Scour around bridge piers
Structural Safety, 2017Co-Authors: Enrico Tubaldi, Lorenzo Macorini, B A Izzuddin, Costantino Manes, Francesco LaioAbstract:Abstract Scouring at the base of bridge piers is the major cause of bridge collapses worldwide. Computing the Scour risk of bridge foundations is therefore key for a correct management and allocation of resources for maintenance and Scour mitigation works. Existing risk-assessment models compute the vulnerability of bridge foundations to Scour by comparing the equilibrium Scour depth associated with peak-flow discharges characterized by a given return period (usually of 100–200 years) with the critical foundation depth of the bridge. This approach neglects completely the history-dependent and time-dependent nature of Scour. Yet, it is well known that bridge collapses can often be induced by the accumulation of Scour during multiple flood events. This study aims at developing a novel probabilistic framework for the computation of bridge-pier vulnerability to Scour using a Markovian approach to account for memory effects in Scour development. The paper focuses on the case of local pier Scour occurring in clear-water conditions whereby cumulative effects are significant, well understood and known to be the cause of recent reported bridge collapses. A simplified numerical example consisting of an idealised bridge pier in a canal is considered to clarify the application of the proposed framework and to shed light on the effects of some assumptions introduced to simplify the probabilistic Scour assessment.
