Model experiments with yacht keels

Numerical analysis of reinforced concrete continuous deep beams

The structural behaviour of deep beams is still not completely understood, since, for example, plane sections do not remain plane and no uniform shear flow can develop because of the small ratio between depth and shear span. If in addition, the supporting system is also statically indeterminate, the number of difficulties increases. In order to...

Statistics of bicycle rider motion

An overview of bicycle and rider kinematic motions from a series of experimental treadmill tests is presented. The full kinematics of bicycles and riders were measured with an active motion capture system. Motion across speeds are compared graphically with box and whiskers plots. Trends and ranges in amplitude are shown to characterize the...

Flow and bathymetry in sharp open-channel bends: Experiments and predictions

This paper focuses on experiments and simulations conducted in very sharp open-channel bends with flat and equilibrium bathymetry, corresponding to the initial and final phases of the erosion and deposition processes, respectively. The study of flow in curved open bends is relevant for flow in natural river configurations, as most river reaches...

Foam Flow Experiments. I. Estimation of the Bubble generation-Coalescence Function

Gas injection leads to foam formation in porous media in the presence of surfactant solutions, which is used for flow diversion and enhanced oil recovery. We present here laboratory experiments of co-injecting nitrogen and sodium C14?16 alpha olefin sulfonate with two concentrations: 20× the critical micelle concentration (CMC) in an...

Experiments on Socio-Technical Systems: The Problem of Control

My aim is to question whether the introduction of new technologies in society may be considered to be genuine experiments. I will argue that they are not, at least not in the sense in which the notion of experiment is being used in the natural and social sciences. If the introduction of a new technology in society is interpreted as an experiment...

Inquiry based learning as didactic model in distant learning

Recent years many universities are involved in development of Massive Open Online Courses (MOOCs). Unfortunately an appropriate didactic model for cooperated network learning is lacking. In this paper we introduce inquiry based learning as didactic model. Students are assumed to ask themselves questions interacting with a learning text. The...

Experimental investigation on breaching of embankments

Breaching of embankments has recently drawn more and more attention due to its importance in the development of early warning systems for embankment failures, in the evacuation plans of people at risk, in the design method of embankments based on a risk-approach, etc. The erosion process observed during embankment breaching tests in the...

Experiments with actively pitch-controlled and spring-loaded oscillating foils

Flat Slabs in Eccentric Punching Shear: Experimental Database and Code Analysis

Eccentric punching shear can occur in concrete slab–column connections when the connection is subjected to shear and unbalanced moments. Unbalanced moments occur in all floor slabs at the edge and corner columns. As such, this problem is of practical relevance. However, most punching experiments in the literature deal with concentric punching...

Self-compacting high-performance fiber concrete for foundations: Part 1 -experimental verification and design considerations

An investigation is carried out into the applicability of self-compacting high-performance fiber concrete (HPFC) in foundations. A concrete mixture has been designed with a concrete cube strength of about 110 MPa. The concrete contains 60 kg/m³ steel fibers. The properties of the HPFC developed are very suitable for structural...

Self-compacting high-performance fiber concrete for foundations: Part 2—Fiber orientation and distribution

An investigation was executed into the applicability of self-compacting high performance fiber concrete in foundations. The applied concrete has a concrete cube strength of about 110 MPa and contains 60 kg/m³ hooked-end steel fibers (<i>L</i>_<i>F</i> = 30 mm, <i>D</i>_<i>F</i> = 0.38 mm). This publication consists...

Sediment Transport of Fine Sand to Fine Gravel on Transverse Bed Slopes in Rotating Annular Flume Experiments

Large-scale morphology, in particular meander bend depth, bar dimensions, and bifurcation dynamics, are greatly affected by the deflection of sediment transport on transverse bed slopes due to gravity and by secondary flows. Overestimating the transverse bed slope effect in morphodynamic models leads to flattening of the morphology, while...

Re-defining the appreciation and usability of urban watersides in the urban center and peri-urban fringes of Shanghai

Countless waterways defined both the rural and urban landscape and related daily life activities in China’s Yangtze River Delta for many centuries. However, much of these bodies of water disappeared due to extremely rapid urbanization in the last three decades and this process is ongoing. This paper critically assesses how the appreciation and...

Momentum Balance Across a Barrier Reef

This paper reports on a combined experimental and numerical study dedicated to barrier reefs hydrodynamics. A network of pressure sensors and velocity profilers has been deployed for more than 2 months over the Ouano reef barrier, New Caledonia. The primary aim of the study is to assess the relevance of the classical depth-averaged momentum...

Experimental study on the 3D-flow field of a free-surface vortex using stereo PIV

In order to analyse the flow characteristics of free-surface vortexes and to validate the Burgers vortex model by using stereo particle image velocimetry, experiments are conducted in a 600 mm diameter vortex tank. Measured axial velocities indicate that 10–25% of the flow is transported through the vortex core. The velocity profiles show that...

Measuring imperfections of water quality sensors in water distribution networks

Water distribution networks (WDNs) are critical to provide safe, clean drinking water around the globe. However, they are susceptible to accidental or deliberate contamination, potentially resulting in poisoned water, many fatalities and large economic consequences. In order to protect against such intrusions, an efficient sensor network...