Stone Stability in Non-uniform Flow

This paper presents the results of an experimental study on stone stability under nonuniform turbulent flow, in particular expanding flow. Detailed measurements of both flow and turbulence and the bed stability are described. Than various manners of quantifying the hydraulic loads exerted on the stones on a bed are extensively reviewed and...

Stone stability under non-uniform flow

Despite the fact that many studies on the stability of stones in bed protections under flowing water have been conducted, our knowledge is still far from advanced and reliable. Issues like how to quantify the hydraulic loads exerted on the stones on a bed and the associated stability of the stones are still central and most challenging in stone...

Stone stability under decelerating open-channel flow

The current research is aimed at finding a proper relation between flow forces acting on the bed and the bed response. To this end, experiments were carried out in which both the bed response (quantified by a dimensionless entrainment rate) and the flow field (velocity and turbulence intensity distributions) are measured. The three available...

Stone stability under non-uniform flow

The current research is aimed at finding a dimensionless stability parameter for non-uniform flow in which the effect of turbulence is incorporated. To this end, experiments were carried out in which both the bed response (quantified by a dimensionless entrainment rate) and the flow field (velocity and turbulence intensity distributions) are...

Experimental data on Stone Stability under non-uniform flow

Previous research (e.g., Jongeling et al 2003; Hofland 2005) has shown that turbulence has an important influence on stone stability and in non-uniform flow it should be modeled explicitly. The dimensionless entrainment rate should be used to describe the bed response because of its complete dependence on local hydrodynamic conditions and...

The B009 data in the backward facing step experiment

This report evaluates the B009 data of the back-ward facing step experiment which was one of a series of the experiments that were designed and conducted by Hofland and Booij (2004) and De Ruijter (2004). In this experiment, the flow field and the pressure field were measured (by PIV and pressure sensors) during the displacement of a single...

Bowthruster-induced damage

The stability of stones in propeller-induced jet wash is still difficult to predict. Especially the trend of bowthrusters increasing in size and power in sea going ships (especially ferries) over the last years may be a reason for concern when dealing with the protection of slopes and beds. But also ships used in inland navigation are using...

Riprap stability on the inner slopes of medium-height breakwaters

Medium height breakwaters are subjected to a considerable amount of overtopping. This implies the armour on the inner slope has to stable against overtopping waves. Existing equations do lack some basic understanding of the process of starting up movement of rock on the inner slopes. In case one relates the stability of the blocks on the inner...

Pressure Sensors and Filtering Techniques for Stone Stability Assessment

This report is structured as follows: In chapter 2 the importance of wall pressures with respect to the present research is described. The literature on wall pressures that was used, and some general features of wall pressure fluctuations are subsequently described in chapter 3. Chapter 4 deals with the pressure sensors. It begins with a brief...