THE FORM OF THE MOUND OF RUBBLE DUMPED BY A BARGE

Abstract

In coastal engineering many structures are (partly) made of rubble or concrete blocks. The usual way of construction is by gradually discharging a specified amount of rubble from a stone dumping barge. The stone dumping barge is steadily repositioned along the structure. To ascertain a geometry as designed in case of a breakwater, a specified evenness in case of a caisson foundation or an acceptable coverage in case of a scour protection a reliable prediction model of the deposition mound of the rubble is needed. Such a model can be helpful in designing and in calculating the cost of the structure. First a model to describe the process af a single stone falling through water, the single stone model (SSM) is given. A mathematical model that describes the dumping from a point source was developed based on the SSM. By integration this model is extended to a description of a line dump as executed by a stationary dumping barge. Finally using the same principle the model is adapted to describe a dump by a laterally translating dumping barge, the area dumping model. In order the verify and to calibrate the SSM a number of experiments were carried out in the Hydualic Laboratory of Delft University of Technology.