The quarter-circular caisson breakwater (QCB) is a new type of breakwater, and it can be applied in deepwater. The stability of QCB under wave force action can be enhanced, and the rubble mound engineering can be le...The quarter-circular caisson breakwater (QCB) is a new type of breakwater, and it can be applied in deepwater. The stability of QCB under wave force action can be enhanced, and the rubble mound engineering can be less than that of semi-circular breakwaters in deepwater. In order to study the wave force distribution acting on the QCB, to find wave force formula for this type of breakwater, firstly in this paper, the distribution characteristics of the horizontal force, the downward vertical force and the uplift force on the breakwater were gotten based on physical model wave flume experiments and on the analysis of the wave pressure experimental data. Based on a series of physical model tests acted by irregular waves, a kind of calculation method, which was modified by Goda formula, was proposed to carry out the wave force on the QCB. Secondly, the reliability method with correlated variables was adopted to analyze the QCB, considering the high correlation between wave forces or moments. Utilizing the observed wave data in engineering field, the reliability index and failure probability of QCB were obtained. Finally, a factor Q=0.9 is given to modify the zero pressure height above SWL of QCB, and wave force partial coefficient 1.34 to the design expressions of QCB for anti-sliding, as well as 1.67 for anti-overturning, were presented.展开更多
This paper describes the use of a numerical and physical modelling study in the design of large breakwaters for a new port and dry dock complex on the southern coast of Oman. The numerical modelling was carried out to...This paper describes the use of a numerical and physical modelling study in the design of large breakwaters for a new port and dry dock complex on the southern coast of Oman. The numerical modelling was carried out to optimise the entrance channel layout with respect to wave penetration into the port and to refine design conditions for the sizing of the primary armour on the breakwaters. Wave conditions inside and outside of the port have been assessed using the 2-dimensional numerical wave penetration model MIKE21 EMS (Elliptic Mild-Slope). As part of the design process, 3D physical modelling studies were also undertaken at Delft Hydraulics in the Netherlands to confirm the stability of the armour on the trunk and roundhead of the breakwaters and to verify the influence of the deep approach channel on stability. The opportunity was taken to extend the physical model tests to assess the influence of the deep channel on wave penetration through the port entrance. The paper focuses on the influence of the deep channel on wave conditions in the entrance to the port and compares the results from the numerical and physical modelling.展开更多
基金Supported by the Natural Science Foundation of Hebei Province (Grant No. E2012201057) the Scientific and Technological Projects of Hebei Province (Grant No. 2009056) the Natural Science Foundation of Tianjin (Grant No. 10JCYBJC03700)
文摘The quarter-circular caisson breakwater (QCB) is a new type of breakwater, and it can be applied in deepwater. The stability of QCB under wave force action can be enhanced, and the rubble mound engineering can be less than that of semi-circular breakwaters in deepwater. In order to study the wave force distribution acting on the QCB, to find wave force formula for this type of breakwater, firstly in this paper, the distribution characteristics of the horizontal force, the downward vertical force and the uplift force on the breakwater were gotten based on physical model wave flume experiments and on the analysis of the wave pressure experimental data. Based on a series of physical model tests acted by irregular waves, a kind of calculation method, which was modified by Goda formula, was proposed to carry out the wave force on the QCB. Secondly, the reliability method with correlated variables was adopted to analyze the QCB, considering the high correlation between wave forces or moments. Utilizing the observed wave data in engineering field, the reliability index and failure probability of QCB were obtained. Finally, a factor Q=0.9 is given to modify the zero pressure height above SWL of QCB, and wave force partial coefficient 1.34 to the design expressions of QCB for anti-sliding, as well as 1.67 for anti-overturning, were presented.
文摘This paper describes the use of a numerical and physical modelling study in the design of large breakwaters for a new port and dry dock complex on the southern coast of Oman. The numerical modelling was carried out to optimise the entrance channel layout with respect to wave penetration into the port and to refine design conditions for the sizing of the primary armour on the breakwaters. Wave conditions inside and outside of the port have been assessed using the 2-dimensional numerical wave penetration model MIKE21 EMS (Elliptic Mild-Slope). As part of the design process, 3D physical modelling studies were also undertaken at Delft Hydraulics in the Netherlands to confirm the stability of the armour on the trunk and roundhead of the breakwaters and to verify the influence of the deep approach channel on stability. The opportunity was taken to extend the physical model tests to assess the influence of the deep channel on wave penetration through the port entrance. The paper focuses on the influence of the deep channel on wave conditions in the entrance to the port and compares the results from the numerical and physical modelling.