Author: Dr.ir. S.A. Miedema

The Application of a Cutting Theory on a Dredging Wheel

Ir. S.A. MIEDEMA Laboratory “The Technology of Soil Movement”

Delft University of Technology SUMMARY AND CONCLUSIONS During the last decades extensive research has been carried out into the fundamental process of dredging. In the Laboratory “The Technology of Soil Movement” of the Delft University of Technology research has been carried out into the forces generated when cutting densely compacted sand under water. In 1974 Joanknecht [4] discerned the importance of the pore pressures and the average dilatation “e” in 1977, but he did not give a method to determine the pore pressures. The determination of the values of these pore pressures only became possible when the necessary software (finite element method) became available. Based on the pore pressure calculations a mathematical model of the cutting forces was set up by Miedema [12]. Equations giving the forces and power requirements for the use of a dredging wheel will be derived from the equations upon which the cutting force model is based. It is possible to expand these equations and to make them suitable for a numerical solution, but those given in this publication will suffice for a preliminary approach and a better insight in the cutting process. The cutting theory was verified by research into the cutting forces on straight blades. A close correlation was obtained between the forces, the pore pressures and the shear angles which were measured and those obtained by calculation ( Miedema [12] ). With the equations derived it is possible to make an estimate of the forces and power requirements, caused by the cutting process on a bucket wheel. It is also possible to determine the thickening of the layer cut on the blade. The latter is especially important in relation to the possibility of the aperture between the buckets becoming clogged. It is difficult to determine the haulage force accurately because this force can change direction not only as a result of wear but also in consequence of variations of the soil mechanical parameters. INTRODUCTION For many years the Laboratory the Technology of Soil Movement has been engaged in fundamental and applied research into the nature of various dredging processes. In this research attention has been paid to the cutting processes in sand, clay and rock. A useful result of this research was the development of the disc bottom cutterhead by Bos and Joanknecht [5] . Towards the end of the seventies, as part of the research of the Offshore Technology Group of the Delft University of Technology, research into the behaviour of sea going cutter section dredgers was started. This led to the development of the computer programme DREDMO in 1983 (see Keuning and Journee [6] , de Koning, Miedema and Zwartbol [7] and Miedema [9,11] ) . The behaviour of sea going cutter suction dredgers is largely determined by the soil/cutterhead interactions, so research into this aspect was necessary. Unfortunately, at the time when this research started there was still no adequate mathematical model available for the determination of the cutting forces in densely compacted sand under

Miedema, S.A., "The Application of a Cutting Theory on a Dredging Wheel (Adobe Acrobat 4.0 PDF-File 745 kB)". Proc. WODCON XI, Brighton 1986.

Copyright: Dr.ir. S.A. Miedema

Author: Dr.ir. S.A. Miedema

water. In the seventies however, it was known that the cutting forces in saturated sand were determined by under pressures in the pore water resulting from dilatation (Joanknecht [4] and van Os [14] ) . Based on this knowledge a theoretical model was developed for cutting with straight blades in densely compacted sand under water. With the aid of characteristic values for the process determining parameters a model was developed for the forces and the torque of a cutter head. The implementation of this model in DREDMO called for a number of simplifications owing to the nature of the computer programme (time domain simulations). Details of the simplified model of the cutting forces were published by Miedema in 1984 [10], while the theoretical background was explained in 1985 [12]. In the near future extrapolation of the cutting theory will make it possible to determine the behaviour of a sea going dredging wheel dredger with the DREDMO programme. In this paper an attempt is made to apply the cutting theory to a dredging wheel. It is assumed that sharp blades with a positive free running angle are used and that there is no cavitation in the pore water during the cutting process. THE THEORETICAL CUTTING FORCE MODEL The cutting process in densely compacted sand under water is determined by the dilatational properties of the sand. Additional factors influencing the process are: - the permeability of the sand - the angle of internal friction of the sand - the soil/interface friction angle - the geometry of the cutting process Figure 1 gives a schematization of the cutting process. The most important parameters are shown in this figure. During the deformation of the sand in the shear zone, the pore volume increases (dilatation). Water must flow in from the surface of the sand to fill this increased volume. This flow of water causes under pressure in the pore water, as a result of which the grain stresses increase and with this the forces required to cut the sand. At high cutting velocities and thus high velocities of the water flowing through the pores, the under pressure becomes so great that saturated water vapour pressure is reached. Cavitation then occurs in the deformation zone. Increasing the cutting velocity will expand the area where the cavitation occurs, with a limit where cavitation occurs on the entire blade. The degree to which under pressure occurs in the pore water depends on the cutting velocity, the thickness of the cut layer and the geometry of the cutting process, but also on soil mechanical parameters (above all the permeability). Types of sand producing quick and slow cavitation can be distinguished although no distinct boundary can be given between them. In addition the occurrence of cavitation also depends upon the depth at which dredging is being performed. This process has already been described by van Os [14], Miedema [10,12], Steeghs [15] and Brakel [1], while the influence of the soil mechanical parameters has been described by van Leussen and Nieuwenhuis [8]. From this it can be deduced that the cutting forces are proportional to the cutting velocity, the increase in the pore volume, the square of the cut layer thickness, the length of the cutting edge and inversely proportional to the permeability of the sand. If it is assumed that no cavitation occurs in the sand, the following general cutting formula (Miedema [12]) can be derived:

m2icwici k/ebhvgcF ⋅⋅⋅⋅⋅ρ⋅= (1)

The proportionality coefficient ci includes the influences of:

Miedema, S.A., "The Application of a Cutting Theory on a Dredging Wheel (Adobe Acrobat 4.0 PDF-File 745 kB)". Proc. WODCON XI, Brighton 1986.

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Author: Dr.ir. S.A. Miedema

- the under pressure on the blade - the under pressure in the deformation zone - the blade angle - the angle of internal friction of the sand - the soil/interface friction angle - the ratio hb/hi - the rate of wear of the blade. For the horizontal component of the force the value of c1 can be found in figure 2 and for the vertical component c2 can be found in figure 3. These figures are valid for cases in which the blade height hb is equal to the thickness of the layer cut hi and no cavitation occurs in the sand. A weighed average between the permeability of the undisturbed sand and the permeability of the deformed sand above the blade should be chosen for the permeability km of the sand. A reasonable estimate can be made by taking the average of the two permeability coefficients. A more accurate determination of km can be obtained with the equation below:

max2i1m kakak ⋅+⋅= With: a1 + a2 = 1 (2) Table 1 gives some of the values for a1 and a2. From this table it appears that a1 and a2 depend upon the geometry of the cutting process.

Table 1: α a1 a2

30° 0.53 0.47 45° 0.53 0.47 60° 0.52 0.48

Figure 1: The plane strain cutting process.

The coefficients are still, though to a lesser degree, dependent upon the soil mechanical properties of the sand. The value of a1 varies between 0.4 and 0.6. For a straight blade the parameters resulting from the geometry of the cutting process are more or less fixed and it is thus useful to be able to make a more accurate estimate of km.

Miedema, S.A., "The Application of a Cutting Theory on a Dredging Wheel (Adobe Acrobat 4.0 PDF-File 745 kB)". Proc. WODCON XI, Brighton 1986.

Copyright: Dr.ir. S.A. Miedema

Author: Dr.ir. S.A. Miedema

The complex geometrical cutting processes of the cutter head and the dredging wheel cause variations in the thickness of the cut layer, the cutting velocity and the blade angle in relation to both time and space. An accurate estimate of km is then only possible using a numerical method to determine the cutting forces. For the method using the characteristic parameters, the characteristic value of km must be determined, which goes with the characteristic cut layer thickness, blade angle etc.

Figure 2: The coefficient c1 as a function of δ and φ. Figure 3: The coefficient c2 as a function of δ and φ. THE FORCES ON THE DREDGING WHEEL In order to render formula 1 useful for the calculation of cutting forces and power requirements for the dredging wheel it is first necessary to analyze the geometry of the cutting process in the dredging wheel. Figures 4 and 5 give a picture of the cutting process in the axial plane and the median plane of the dredging wheel. The cutting velocity, the cut layer thickness and the length of the cutting edge are a function of the haulage speed, the number of revolutions, the length of the step, the dimensions of the dredging wheel and the height of the slope, whilst the length of the cutting edge also varies with time. Unlike the cutter head the dredging wheel has a cut layer thickness which is constant in time, but which is dependent upon its position on the cutting edge (fig. 4). The following equation can be derived for the thickness of the cut layer as a function of the distance r to the axis of the dredging wheel:

s cii 2 2

ci s

v 60 vh

n z v v

⋅= ⋅

⋅ +

(3)

Miedema, S.A., "The Application of a Cutting Theory on a Dredging Wheel (Adobe Acrobat 4.0 PDF-File 745 kB)". Proc. WODCON XI, Brighton 1986.

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Author: Dr.ir. S.A. Miedema

r60

2nvci ⋅⋅

=π (4)

From figure 5 it can be seen that when the blade enters the slope, only the outermost part of the cutting edge is involved in the cutting process. The length of the cutting edge which is involved in the cutting process is thus not constant in time. The cutting velocity is also at its greatest on the outer circumference on the dredging wheel, so that the greatest cutting forces are also developed there (eqn. 1). This partially explains for the fact that the greatest wear occurs on the outer circumference. For the cutting force model it is important to find a characteristic cutting velocity, cut layer thickness, length of the cutting edge and radius for the dredging wheel. Because there is a linear increase in cutting forces proportional to the increase in cutting velocity, the following can be derived for the average cutting force:

Ω⋅⋅⋅Ω⋅⋅π⋅

⋅⋅⋅⋅⋅ρ⋅= ∫ ∫Ω

Ω

ddrr60

n2k1ehgcF

o

0

R

)(rom

2iwici With: Ω = ω ⋅ t (5)

Provided that the dynamical blade angle and the cut layer thickness are constant over the cutting edge which is approximately the case. For the area of the longitudinal cross section:

∫ ∫ ⋅⋅=o

0

R

)(r

ddrrAΩ

Ω

Ω (6)

can be derived. The radius r(Ω) is the distance from the axis of the dredging wheel to the breach (fig. 6) . From the equations 5 and 6 it follows:

A60

n2k1ehgcF

om

2iwici ⋅

⋅⋅⋅

⋅⋅⋅⋅⋅⋅=Ωπ

ρ (7)

Now a radius R1 can be defined so that the area of the part of the circle segment in figure 6 equals the area of the longitudinal cross section. With:

SBA ⋅≈ (8) and

⎟⎠⎞

⎜⎝⎛

⋅+⎟

⎠⎞

⎜⎝⎛ −

=R2

SarcsinR

BRarccosoΩ (9)

It follows that

⎟⎟⎠

⎞⎜⎜⎝

⎛⎟⎟⎠

⎞⎜⎜⎝

⎛⋅−⋅= A2R1R

o

21 Ω

ππ

π (10)

Miedema, S.A., "The Application of a Cutting Theory on a Dredging Wheel (Adobe Acrobat 4.0 PDF-File 745 kB)". Proc. WODCON XI, Brighton 1986.

Copyright: Dr.ir. S.A. Miedema

Author: Dr.ir. S.A. Miedema

This gives for the characteristic radius:

( )2

RRR 1

char+

= (11) Hence:

60Rn2

v charcichar

⋅⋅=

π (12)

so that for the characteristic cutting velocity:

( )2s

2cicharcchar vvv +=

(13) is valid. The characteristic length of the cutting edge is now:

1char RRb −= (14)

Figure 4: The cutting process in the axial plane of the dredging wheel.

Miedema, S.A., "The Application of a Cutting Theory on a Dredging Wheel (Adobe Acrobat 4.0 PDF-File 745 kB)". Proc. WODCON XI, Brighton 1986.

Copyright: Dr.ir. S.A. Miedema

Author: Dr.ir. S.A. Miedema

The characteristic cut layer thickness follows from equation 2 when the characteristic radius is substituted for the radius r (eqn. 3). Substituting the characteristic values for the cut layer thickness, the blade width and the cutting velocity in equation 1 gives the average force on a blade as long as this is in contact with the breach. To determine the total resultant force the following is valid:

πΩ

2z

FF ocicitot

⋅⋅= (15)

Figure 5: The cutting process in the median plane of the dredging wheel.

THE DIRECTION OF THE CUTTING FORCE The cutting force on the dredging wheel can be resolved into a tangential component and an axial component (fig. 7). The tangential component is more or less equivalent to the horizontal force on a straight blade, while the axial component is equivalent to the vertical force on the straight blade (fig. 1). A correction for the direction of the cutting velocity is necessary if the angle resulting from the circumferential velocity and the haulage velocity becomes too great (fig. 7). The tangential and axial forces can be determined by substituting the characteristic cut layer thickness, length of the edge involved in the cutting process and cutting velocity in equation 1 and by determining the coefficient ci for both forces with the aid of figures 2 and 3. The blade angle will in fact never be precisely 30° or 45°. An interpolation or extrapolation (α<30°) is then necessary. Linear interpolation or extrapolation is obtained by determining the values of ci for α=30° and α=45° and drawing a straight line through them (fig. 8). A greater degree of accuracy can be obtained by determining the values of ci for α=30°, α=45° and α=60° and drawing a parabola through them (fig. 8).

Miedema, S.A., "The Application of a Cutting Theory on a Dredging Wheel (Adobe Acrobat 4.0 PDF-File 745 kB)". Proc. WODCON XI, Brighton 1986.

Copyright: Dr.ir. S.A. Miedema

Author: Dr.ir. S.A. Miedema

Figure 6: The substituting circle segment.

The torque of the drive can be now determined by the use of:

tottancchardw FRM ⋅= (16) so that for the driving power:

602nMP dwdwπ⋅

⋅= (17)

is valid. Theoretically for the haulage power

scaxtots vFP ⋅= (18) is valid. It is noteworthy that the axial force has the same direction as the haulage velocity. This indicates that the cutting process produces haulage power. In fact this is only valid in cases where there is a pure cutting process. With blade angles greater than ≈ 40° the direction of the axial force can reverse. Because the blade angle of the dredging wheel extends form ≈ 45° where the radius is the smallest, to ≈ 30° at the outer edge of the wheel, it may be possible that the axial force changes direction on the blade. This also depends on the soil mechanical parameters. A numerical determination of the cutting forces can provide more information about this. As soon as there is any question of a run up of the sand to the back of the blade (negative free running angle) the direction of the axial force can reverse and power is required for the haulage.

Miedema, S.A., "The Application of a Cutting Theory on a Dredging Wheel (Adobe Acrobat 4.0 PDF-File 745 kB)". Proc. WODCON XI, Brighton 1986.

Copyright: Dr.ir. S.A. Miedema

Author: Dr.ir. S.A. Miedema

By means of measurements in two types of soil in the field, van Drimmelen en Eijgenraam [2] have established that the part of the haulage force resulting from the cutting force may be positive or negative. From the cutting theory it is not yet possible to determine the influence of wear (dullness of the cutting edge) but it is probable that the axial force will also be reversed in this case.

Figure 7: The direction of the cutting forces.

Figure 8: Interpolation to gain the coefficients c1 and c2 ( linear above, quadratic below).

Miedema, S.A., "The Application of a Cutting Theory on a Dredging Wheel (Adobe Acrobat 4.0 PDF-File 745 kB)". Proc. WODCON XI, Brighton 1986.

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Author: Dr.ir. S.A. Miedema

THE INFLUENCE OF THE SHEAR ANGLE In the dredging wheel there is a certain aperture between the buckets. The blade angle is greater than the angle which the blade makes with the vertical. A consequence of this is that, depending on the thickness of the cut layer and the shear angle, it is possible for the cut layer to run up against the back of the preceding bucket. This is shown in figure 9. In this case the thickness of the deformed cut layer is equal to the aperture d between the buckets. The cut layer thickness is determined by the haulage velocity and the number of revolutions of the dredging wheel and is thus a value which can be directly influenced. The angle of shear depends not only on the geometry of the cutting process but also on the soil mechanical properties of the sand. In the theory of the cutting of dry soil use is commonly made of a shear angle of 45-1/2φ with the horizontal. From modern soil mechanics it appears that a shear angle of 45-1/2ν is also possible. Both shear angles can be observed experimentally (Vermeer [16]). In this it is assumed that the main stress directions are horizontal and vertical. This is not the case for the cutting process and thus it cannot be assumed that the shear angles mentioned above will be found. One way of determining the angle of shear is to select the value at which the change in the energy absorbed in the sand due the volume changes and transformed into heat is minimized (Rowe [17]). This will be described in a future publication. The shear angle is then a function of the blade angle, the angle of soil/interface friction, the angle of internal friction and the ratio between the height of the blade and the thickness of the cut layer. Figure 10 gives the shear angles for the case that hb = hi . From this theory in fact it is possible to determine the angle of shear for all blade angles up to ≈60°. With a blade angle greater than 60° the mechanism of the cutting process changes. In dry soil this can be demonstrated by the “wedge theory” of Hettiaratchy and Reece [3]. It is possible to show the “wedge theory’ theoretically for the cutting of densely compacted sand under water but further consideration of this is beyond the scope of this paper.

Figure 9: A run up against the back of the preceeding bucket.

Miedema, S.A., "The Application of a Cutting Theory on a Dredging Wheel (Adobe Acrobat 4.0 PDF-File 745 kB)". Proc. WODCON XI, Brighton 1986.

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Author: Dr.ir. S.A. Miedema

APPLICATION OF THE THEORY To illustrate the theory which has been described an example of a calculation of the forces on a dredging wheel will be given. The information relating to the dredging wheel is taken from the publication of Eijgenraam and van Drimmelen [2]. Soil mechanical properties of the sand. φ = 40° δ = 26° e = 10% km = 10-4 m/s Dredging wheel. R = 2.2 m n = 13 rpm bmax = 1.1 m z = 15 buckets vs = 0.3 m/s α = 36° S = 1 m B = 1 m This gives: hichar 0.092 m vcchar 2.73 m/s β 30.5 ° bchar 0.41 m Rchar 1.99 m ctan 0.30 cax 0.135 Ωo 70° α’ 30° From this follows: Fctantot 83 kN Fcaxtot - 37 kN Mdw 165 kNm Pdw 224 kW Ps - 11 kW From the initial cut layer thickness, blade angle and shear angle, the thickness of the deformed cut layer is:

)sin()sin(hh idef β

β+α⋅=

(19)

This gives: hdef = 0.159 m

Miedema, S.A., "The Application of a Cutting Theory on a Dredging Wheel (Adobe Acrobat 4.0 PDF-File 745 kB)". Proc. WODCON XI, Brighton 1986.

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Here it is still possible to speak of a pure cutting process. Increasing the haulage velocity can cause a run up against the back of the preceding bucket, depending on the aperture. With the aid of figure 10 it is possible to calculate the thickness hdef and thus at which haulage velocity the sand will run up against the back of the preceding bucket. It must be realized that other types of soil will produce other demands with regard to the means of cutting. However, the extrapolation of the cutting theory for straight blades to the dredging wheel increases the insight into the complicated cutting process which is involved. The choice must be made between a generalized model or a detailed numerical model is principally determined by the use to which the model will be put. In the design phase of a dredging wheel it is useful to know with the greatest possible degree of accuracy not only the magnitude of the forces on the edge of the blade, but also their distribution. For this purpose a numerical model is most suitable. The detailed numerical method is too time consuming for computer programmes such as DREDMO, which are intended for the determination of the behaviour of dredging vessels (cutter suction dredgers and dredging wheel dredgers) in swell. In addition small variations in the total cutting forces have little effect upon the movement of the dredger. In such cases a generalized cutting force model (like the model presented in this paper) is more suitable. Both types of model are receiving attention within the framework of the research in the Laboratory the Technology of Soil Movement.

Figure 10: The shear angle β as a function of δ and φ.

Miedema, S.A., "The Application of a Cutting Theory on a Dredging Wheel (Adobe Acrobat 4.0 PDF-File 745 kB)". Proc. WODCON XI, Brighton 1986.

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Author: Dr.ir. S.A. Miedema

NOMENCLATURE a1,a2 Coefficients A Cross section m2

b Length of the edge of the blade M bmax Maximum length of the edge of the blade M bchar Characteristic length of the edge of the blade M B Heigth of the breach M ci Coefficient for the determination of forces c1, ctan Coefficient of the horizontal (tangential) force c2, cax Coefficient of the vertical (axial) force d Aperture between two buckets m e Volume strain % Fci Cutting force kN Fcitot Total cutting force in one direction kN Fctan Tangential cutting force on one bucket kN Fctantot Total tangential cutting force kN Fcax Axial cutting force on one bucket kN Fcaxtot Total axial cutting force kn. g Gravitational acceleration m/s2

hi Initial cut layer thickness m hob Height of the blade m hichar Characteristic initial cut layer thickness m hdef Thickness of the deformed cut layer m km Weighed permeability m/s ki Initial permeability m/s kmax Permeability of the deformed sand m/s Mdw Torque on dredging wheel kNm n Number of revolutions of the dredging wheel rpm Pdw Power (rotational) kW Ps Power (haulage) kW r Radius m R Radius of dredging wheel m R1 Radius m Rchar Characteristic radius m S Step of the dredger m vc Cutting velocity m/s vcchar Characteristic cutting velocity m/s vs Haulage (swing) velocity m/s vci Circumferential velocity m/s vcichar Characteristic circumferential velocity m/s z Number of buckets on the dredging wheel α Initial blade angle deg (rad) α’ Dynamical blade angle deg (rad) β Shear angle deg (rad) δ Soil/interface friction angle deg (rad) ϕ Angle of internal friction deg (rad) ρw Density of water ton/m3

θ Initial free running angle deg (rad)

Miedema, S.A., "The Application of a Cutting Theory on a Dredging Wheel (Adobe Acrobat 4.0 PDF-File 745 kB)". Proc. WODCON XI, Brighton 1986.

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θ’ Dynamical free running angle deg (rad) Ωo Angle along which a bucket is cutting deg (rad) ν Angle of dilatation deg (rad) ω Angular velocity rad/sec BIBLIOGRAPHY [1] Brakel, J.D., “Mathematisch model voor de krachten op een roterende snijkop van

een in zeegang werkende snijkopzuiger”. ScO/80/96. T.H. Delft 1981. [2] Drimmelen, N.J.van, ‘t Hoen, J.P.T.A., Willigen, F.A. and Eijgenraam, J.A., “Development and First Production Unit of the IHC Beaver Wheel Dredger”. Proc. Wodcon 1983, Singapore 1983. [3] Hettiaratchi, D.R.P. and Reece, A.R., “Boundary Wedges in Two Dimensional Passive

Soil Failure”. Geotechnique 25, No.2, pp. 197-220, 1975 [4] Joanknecht, L.W.F., “Cutting Forces in Submerged Soils’. T.H. Delft, 1974, The

Netherlands. [5] Joanknecht, L.W.F., “Results of Tests on Two Cutterheads operating in Sand”. First

Int.Symp. Dredging Technology, Canterbury, England, 1975. [6] Keuning, P.J. & Journee, J., “Calculation Method for the behaviour of a Cutter

Suction Dredging operating in Irregular Waves”. Proc. Wodcon X, Singapore 1983. [7] Koning, J. de & Miedema, S.A. & Zwartbol, A., “Soil/Cutterhead Interaction under

Wave Conditions”. Proc. Wodcon X, Singapore, 1983. [8] Leussen, W.van & Nieuwenhuis, J.D., “Soil Mechanics Aspects of Dredging”.

Geotechnique 34 No. 3, pp. 359-381 [9] Miedema, S.A., “De interactie tussen snijkop en grond in zeegang”. Proc. Baggerdag

19/11/1982, TH Delft, 1982. [10] Miedema, S.A., “The cutting of densely compacted sand under water”.Terra et Aqua

No. 28, October 1984, pp. 4-10 [11] Miedema, S.A., “ Mathematische modelvorming t.a.v. een snijkopzuiger in zeegang”.

TH Delft 1984. (KIVI September 1984), The Netherlands. [12] Miedema, S.A., “Mathematical Modelling of the Cutting of Densely Compacted Sand

Under Water”. Dredging & Port Construction, July 1985, pp.22-26. [13] Meijer, K.L. & Os, A.G.van, “Pore Ressures near moving Under Water Slope”.

Geotechn. Engng. Div. ASCE 102, No. GT4, pp. 361-372 [14] Os, A.G.van, “Behaviour of Soil when excavated Under Water”. International Course

Modern Dredging. June 1977, The Hague, The Netherlands. [15] Steeghs, H., “Snijden van zand onder water (I & II)”. Ports & Dredging No. 121, June

1985. [16] Vermeer, P.A., “Materiaalmodellen in de grondmechanica”. T.H. Delft, 1983, The

Netherlands (collegedictaat). [17] Rowe, P.W., “The stress Dilatancy Relation for Static Equilibrium of an Assembly of

Particles in Contact”. Proc. Royal Soc. Series A, Vol. 269, pp. 500-527, 1962.

Miedema, S.A., "The Application of a Cutting Theory on a Dredging Wheel (Adobe Acrobat 4.0 PDF-File 745 kB)". Proc. WODCON XI, Brighton 1986.

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Bibliography Dr.ir. S.A. Miedema 1980-2010

1. Koert, P. & Miedema, S.A., "Report on the field excursion to the USA April 1981" (PDF in Dutch 27.2 MB). Delft University of Technology, 1981, 48 pages.

2. Miedema, S.A., "The flow of dredged slurry in and out hoppers and the settlement process in hoppers" (PDF in Dutch 37 MB). ScO/81/105, Delft University of Technology, 1981, 147 pages.

3. Miedema, S.A., "The soil reaction forces on a crown cutterhead on a swell compensated ladder" (PDF in Dutch 19 MB). LaO/81/97, Delft University of Technology, 1981, 36 pages.

4. Miedema, S.A., "Computer program for the determination of the reaction forces on a cutterhead, resulting from the motions of the cutterhead" (PDF in Dutch 11 MB). Delft Hydraulics, 1981, 82 pages.

5. Miedema, S.A. "The mathematical modeling of the soil reaction forces on a cutterhead and the development of the computer program DREDMO" (PDF in Dutch 25 MB). CO/82/125, Delft University of Technology, 1982, with appendices 600 pages.

6. Miedema, S.A.,"The Interaction between Cutterhead and Soil at Sea" (In Dutch). Proc. Dredging Day November 19th, Delft University of Technology 1982.

7. Miedema, S.A., "A comparison of an underwater centrifugal pump and an ejector pump" (PDF in Dutch 3.2 MB). Delft University of Technology, 1982, 18 pages.

8. Miedema, S.A., "Computer simulation of Dredging Vessels" (In Dutch). De Ingenieur, Dec. 1983. (Kivi/Misset).

9. Koning, J. de, Miedema, S.A., & Zwartbol, A., "Soil/Cutterhead Interaction under Wave Conditions (Adobe Acrobat PDF-File 1 MB)". Proc. WODCON X, Singapore 1983.

10. Miedema, S.A. "Basic design of a swell compensated cutter suction dredge with axial and radial compensation on the cutterhead" (PDF in Dutch 20 MB). CO/82/134, Delft University of Technology, 1983, 64 pages.

11. Miedema, S.A., "Design of a seagoing cutter suction dredge with a swell compensated ladder" (PDF in Dutch 27 MB). IO/83/107, Delft University of Technology, 1983, 51 pages.

12. Miedema, S.A., "Mathematical Modeling of a Seagoing Cutter Suction Dredge" (In Dutch). Published: The Hague, 18-9-1984, KIVI Lectures, Section Under Water Technology.

13. Miedema, S.A., "The Cutting of Densely Compacted Sand under Water (Adobe Acrobat PDF-File 575 kB)". Terra et Aqua No. 28, October 1984 pp. 4-10.

14. Miedema, S.A., "Longitudinal and Transverse Swell Compensation of a Cutter Suction Dredge" (In Dutch). Proc. Dredging Day November 9th 1984, Delft University of Technology 1984.

15. Miedema, S.A., "Compensation of Velocity Variations". Patent application no. 8403418, Hydromeer B.V. Oosterhout, 1984.

16. Miedema, S.A., "Mathematical Modeling of the Cutting of Densely Compacted Sand Under Water". Dredging & Port Construction, July 1985, pp. 22-26.

17. Miedema, S.A., "Derivation of the Differential Equation for Sand Pore Pressures". Dredging & Port Construction, September 1985, pp. 35.

18. Miedema, S.A., "The Application of a Cutting Theory on a Dredging Wheel (Adobe Acrobat 4.0 PDF-File 745 kB)". Proc. WODCON XI, Brighton 1986.

19. Miedema, S.A., "Underwater Soil Cutting: a Study in Continuity". Dredging & Port Construction, June 1986, pp. 47-53.

20. Miedema, S.A., "The cutting of water saturated sand, laboratory research" (In Dutch). Delft University of Technology, 1986, 17 pages.

21. Miedema, S.A., "The forces on a trenching wheel, a feasibility study" (In Dutch). Delft, 1986, 57 pages + software.

22. Miedema, S.A., "The translation and restructuring of the computer program DREDMO from ALGOL to FORTRAN" (In Dutch). Delft Hydraulics, 1986, 150 pages + software.

23. Miedema, S.A., "Calculation of the Cutting Forces when Cutting Water Saturated Sand (Adobe Acrobat 4.0 PDF-File 16 MB)". Basic Theory and Applications for 3-D Blade Movements and Periodically Varying Velocities for, in Dredging Commonly used Excavating Means. Ph.D. Thesis, Delft University of Technology, September 15th 1987.

24. Bakker, A. & Miedema, S.A., "The Specific Energy of the Dredging Process of a Grab Dredge". Delft University of Technology, 1988, 30 pages.

25. Miedema, S.A., "On the Cutting Forces in Saturated Sand of a Seagoing Cutter Suction Dredge (Adobe Acrobat 4.0 PDF-File 1.5 MB)". Proc. WODCON XII, Orlando, Florida, USA, April 1989. This paper was given the IADC Award for the best technical paper on the subject of dredging in 1989.

26. Miedema, S.A., "The development of equipment for the determination of the wear on pick-points" (In Dutch). Delft University of Technology, 1990, 30 pages (90.3.GV.2749, BAGT 462).

27. Miedema, S.A., "Excavating Bulk Materials" (In Dutch). Syllabus PATO course, 1989 & 1991, PATO The Hague, The Netherlands.

28. Miedema, S.A., "On the Cutting Forces in Saturated Sand of a Seagoing Cutter Suction Dredge (Adobe Acrobat 4.0 PDF-File 1.5 MB)". Terra et Aqua No. 41, December 1989, Elseviers Scientific Publishers.

29. Miedema, S.A., "New Developments of Cutting Theories with respect to Dredging, the Cutting of Clay (Adobe Acrobat 4.0 PDF-File 640 kB)". Proc. WODCON XIII, Bombay, India, 1992.

30. Davids, S.W. & Koning, J. de & Miedema, S.A. & Rosenbrand, W.F., "Encapsulation: A New Method for the Disposal of Contaminated Sediment, a Feasibility Study (Adobe Acrobat 4.0 PDF-File 3MB)". Proc. WODCON XIII, Bombay, India, 1992.

31. Miedema, S.A. & Journee, J.M.J. & Schuurmans, S., "On the Motions of a Seagoing Cutter Dredge, a Study in Continuity (Adobe Acrobat 4.0 PDF-File 396 kB)". Proc. WODCON XIII, Bombay, India, 1992.

32. Becker, S. & Miedema, S.A. & Jong, P.S. de & Wittekoek, S., "On the Closing Process of Clamshell Dredges in Water Saturated Sand (Adobe Acrobat 4.0 PDF-File 1 MB)". Proc. WODCON XIII, Bombay, India, 1992. This paper was given the IADC Award for the best technical paper on the subject of dredging in 1992.

33. Becker, S. & Miedema, S.A. & Jong, P.S. de & Wittekoek, S., "The Closing Process of Clamshell Dredges in Water Saturated Sand (Adobe Acrobat 4.0 PDF-File 1 MB)". Terra et Aqua No. 49, September 1992, IADC, The Hague.

34. Miedema, S.A., "Modeling and Simulation of Dredging Processes and Systems". Symposium "Zicht op Baggerprocessen", Delft University of Technology, Delft, The Netherlands, 29 October 1992.

35. Miedema, S.A., "Dredmo User Interface, Operators Manual". Report: 92.3.GV.2995. Delft University of Technology, 1992, 77 pages.

36. Miedema, S.A., "Inleiding Mechatronica, college WBM202" Delft University of Technology, 1992.

37. Miedema, S.A. & Becker, S., "The Use of Modeling and Simulation in the Dredging Industry, in Particular the Closing Process of Clamshell Dredges", CEDA Dredging Days 1993, Amsterdam, Holland, 1993.

38. Miedema, S.A., "On the Snow-Plough Effect when Cutting Water Saturated Sand with Inclined Straight Blades (Adobe Acrobat 4.0 PDF-File 503 kB)". ASCE Proc. Dredging 94, Orlando, Florida, USA, November 1994. Additional Measurement Graphs. (Adobe Acrobat 4.0 PDF-File 209 kB).

39. Riet, E. van, Matousek, V. & Miedema, S.A., "A Reconstruction of and Sensitivity Analysis on the Wilson Model for Hydraulic Particle Transport (Adobe Acrobat 4.0 PDF-File 50 kB)". Proc. 8th Int. Conf. on Transport and Sedimentation of Solid Particles, 24-26 January 1995, Prague, Czech Republic.

40. Vlasblom, W.J. & Miedema, S.A., "A Theory for Determining Sedimentation and Overflow Losses in Hoppers (Adobe Acrobat 4.0 PDF-File 304 kB)". Proc. WODCON IV, November 1995, Amsterdam, The Netherlands 1995.

41. Miedema, S.A., "Production Estimation Based on Cutting Theories for Cutting Water Saturated Sand (Adobe Acrobat 4.0 PDF-File 423 kB)". Proc. WODCON IV, November 1995, Amsterdam, The Netherlands 1995. Additional Specific Energy and Production Graphs. (Adobe Acrobat 4.0 PDF-File 145 kB).

42. Riet, E.J. van, Matousek, V. & Miedema, S.A., "A Theoretical Description and Numerical Sensitivity Analysis on Wilson's Model for Hydraulic Transport in Pipelines (Adobe Acrobat 4.0 PDF-File 50 kB)". Journal of Hydrology & Hydromechanics, Slovak Ac. of Science, Bratislava, June 1996.

43. Miedema, S.A. & Vlasblom, W.J., "Theory for Hopper Sedimentation (Adobe Acrobat 4.0 PDF-File 304 kB)". 29th Annual Texas A&M Dredging Seminar. New Orleans, June 1996.

44. Miedema, S.A., "Modeling and Simulation of the Dynamic Behavior of a Pump/Pipeline System (Adobe Acrobat 4.0 PDF-File 318 kB)". 17th Annual Meeting & Technical Conference of the Western Dredging Association. New Orleans, June 1996.

45. Miedema, S.A., "Education of Mechanical Engineering, an Integral Vision". Faculty O.C.P., Delft University of Technology, 1997 (in Dutch).

46. Miedema, S.A., "Educational Policy and Implementation 1998-2003 (versions 1998, 1999 and 2000) (Adobe Acrobat 4.0 PDF_File 195 kB)". Faculty O.C.P., Delft University of Technology, 1998, 1999 and 2000 (in Dutch).

47. Keulen, H. van & Miedema, S.A. & Werff, K. van der, "Redesigning the curriculum of the first three years of the mechanical engineering curriculum". Proceedings of the International Seminar on Design in Engineering Education, SEFI-Document no.21, page 122, ISBN 2-87352-024-8, Editors: V. John & K. Lassithiotakis, Odense, 22-24 October 1998.

48. Miedema, S.A. & Klein Woud, H.K.W. & van Bemmel, N.J. & Nijveld, D., "Self Assesment Educational Programme Mechanical Engineering (Adobe Acrobat 4.0 PDF-File 400 kB)". Faculty O.C.P., Delft University of Technology, 1999.

49. Van Dijk, J.A. & Miedema, S.A. & Bout, G., "Curriculum Development Mechanical Engineering". MHO 5/CTU/DUT/Civil Engineering. Cantho University Vietnam, CICAT Delft, April 1999.

50. Miedema, S.A., "Considerations in building and using dredge simulators (Adobe Acrobat 4.0 PDF-File 296 kB)". Texas A&M 31st Annual Dredging Seminar. Louisville Kentucky, May 16-18, 1999.

51. Miedema, S.A., "Considerations on limits of dredging processes (Adobe Acrobat 4.0 PDF-File 523 kB)". 19th Annual Meeting & Technical Conference of the Western Dredging Association. Louisville Kentucky, May 16-18, 1999.

52. Miedema, S.A. & Ruijtenbeek, M.G. v.d., "Quality management in reality", "Kwaliteitszorg in de praktijk". AKO conference on quality management in education. Delft University of Technology, November 3rd 1999.

53. Miedema, S.A., "Curriculum Development Mechanical Engineering (Adobe Acrobat 4.0 PDF-File 4 MB)". MHO 5-6/CTU/DUT. Cantho University Vietnam, CICAT Delft, Mission October 1999.

54. Vlasblom, W.J., Miedema, S.A., Ni, F., "Course Development on Topic 5: Dredging Technology, Dredging Equipment and Dredging Processes". Delft University of Technology and CICAT, Delft July 2000.

55. Miedema, S.A., Vlasblom, W.J., Bian, X., "Course Development on Topic 5: Dredging Technology, Power Drives, Instrumentation and Automation". Delft University of Technology and CICAT, Delft July 2000.

56. Randall, R. & Jong, P. de & Miedema, S.A., "Experience with cutter suction dredge simulator training (Adobe Acrobat 4.0 PDF-File 1.1 MB)". Texas A&M 32nd Annual Dredging Seminar. Warwick, Rhode Island, June 25-28, 2000.

57. Miedema, S.A., "The modelling of the swing winches of a cutter dredge in relation with simulators (Adobe Acrobat 4.0 PDF-File 814 kB)". Texas A&M 32nd Annual Dredging Seminar. Warwick, Rhode Island, June 25-28, 2000.

58. Hofstra, C. & Hemmen, A. van & Miedema, S.A. & Hulsteyn, J. van, "Describing the position of backhoe dredges (Adobe Acrobat 4.0 PDF-File 257 kB)". Texas A&M 32nd Annual Dredging Seminar. Warwick, Rhode Island, June 25-28, 2000.

59. Miedema, S.A., "Automation of a Cutter Dredge, Applied to the Dynamic Behaviour of a Pump/Pipeline System (Adobe Acrobat 4.0 PDF-File 254 kB)". Proc. WODCON VI, April 2001, Kuala Lumpur, Malaysia 2001.

60. Heggeler, O.W.J. ten, Vercruysse, P.M., Miedema, S.A., "On the Motions of Suction Pipe Constructions a Dynamic Analysis (Adobe Acrobat 4.0 PDF-File 110 kB)". Proc. WODCON VI, April 2001, Kuala Lumpur, Malaysia 2001.

61. Miedema, S.A. & Zhao Yi, "An Analytical Method of Pore Pressure Calculations when Cutting Water Saturated Sand (Adobe Acrobat PDF-File 2.2 MB)". Texas A&M 33nd Annual Dredging Seminar, June 2001, Houston, USA 2001.

62. Miedema, S.A., "A Numerical Method of Calculating the Dynamic Behaviour of Hydraulic Transport (Adobe Acrobat PDF-File 246 kB)". 21st Annual Meeting & Technical Conference of the Western Dredging Association, June 2001, Houston, USA 2001.

63. Zhao Yi, & Miedema, S.A., "Finite Element Calculations To Determine The Pore Pressures When Cutting Water Saturated Sand At Large Cutting Angles (Adobe Acrobat PDF-File 4.8 MB)". CEDA Dredging Day 2001, November 2001, Amsterdam, The Netherlands.

64. Miedema, S.A., "Mission Report Cantho University". MHO5/6, Phase Two, Mission to Vietnam by Dr.ir. S.A. Miedema DUT/OCP Project Supervisor, 27 September-8 October 2001, Delft University/CICAT.

65. (Zhao Yi), & (Miedema, S.A.), "

" (Finite Element Calculations To Determine The Pore Pressures When Cutting Water

Saturated Sand At Large Cutting Angles (Adobe Acrobat PDF-File 4.8 MB))". To be published in 2002.

66. Miedema, S.A., & Riet, E.J. van, & Matousek, V., "Theoretical Description And Numerical Sensitivity Analysis On Wilson Model For Hydraulic Transport Of Solids In Pipelines (Adobe Acrobat PDF-File 147 kB)". WEDA Journal of Dredging Engineering, March 2002.

67. Miedema, S.A., & Ma, Y., "The Cutting of Water Saturated Sand at Large Cutting Angles (Adobe Acrobat PDF-File 3.6 MB)". Proc. Dredging02, May 5-8, Orlando, Florida, USA.

68. Miedema, S.A., & Lu, Z., "The Dynamic Behavior of a Diesel Engine (Adobe Acrobat PDF-File 363 kB)". Proc. WEDA XXII Technical Conference & 34th Texas A&M Dredging Seminar, June 12-15, Denver, Colorado, USA.

69. Miedema, S.A., & He, Y., "The Existance of Kinematic Wedges at Large Cutting Angles (Adobe Acrobat PDF-File 4 MB)". Proc. WEDA XXII Technical Conference & 34th Texas A&M Dredging Seminar, June 12-15, Denver, Colorado, USA.

70. Ma, Y., Vlasblom, W.J., Miedema, S.A., Matousek, V., "Measurement of Density and Velocity in Hydraulic Transport using Tomography". Dredging Days 2002, Dredging without boundaries, Casablanca, Morocco, V64-V73, 22-24 October 2002.

71. Ma, Y., Miedema, S.A., Vlasblom, W.J., "Theoretical Simulation of the Measurements Process of Electrical Impedance Tomography". Asian Simulation Conference/5th International Conference on System Simulation and Scientific Computing, Shanghai, 3-6 November 2002, p. 261-265, ISBN 7-5062-5571-5/TP.75.

72. Thanh, N.Q., & Miedema, S.A., "Automotive Electricity and Electronics". Delft University of Technology and CICAT, Delft December 2002.

73. Miedema, S.A., Willemse, H.R., "Report on MHO5/6 Mission to Vietnam". Delft University of Technology and CICAT, Delft Januari 2003.

74. Ma, Y., Miedema, S.A., Matousek, V., Vlasblom, W.J., "Tomography as a Measurement Method for Density and Velocity Distributions". 23rd WEDA Technical Conference & 35th TAMU Dredging Seminar, Chicago, USA, june 2003.

75. Miedema, S.A., Lu, Z., Matousek, V., "Numerical Simulation of a Development of a Density Wave in a Long Slurry Pipeline". 23rd WEDA Technical Conference & 35th TAMU Dredging Seminar, Chicago, USA, june 2003.

76. Miedema, S.A., Lu, Z., Matousek, V., "Numerical simulation of the development of density waves in a long pipeline and the dynamic system behavior". Terra et Aqua, No. 93, p. 11-23.

77. Miedema, S.A., Frijters, D., "The Mechanism of Kinematic Wedges at Large Cutting Angles - Velocity and Friction Measurements". 23rd WEDA Technical Conference & 35th TAMU Dredging Seminar, Chicago, USA, june 2003.

78. Tri, Nguyen Van, Miedema, S.A., Heijer, J. den, "Machine Manufacturing Technology". Lecture notes, Delft University of Technology, Cicat and Cantho University Vietnam, August 2003.

79. Miedema, S.A., "MHO5/6 Phase Two Mission Report". Report on a mission to Cantho University Vietnam October 2003. Delft University of Technology and CICAT, November 2003.

80. Zwanenburg, M., Holstein, J.D., Miedema, S.A., Vlasblom, W.J., "The Exploitation of Cockle Shells". CEDA Dredging Days 2003, Amsterdam, The Netherlands, November 2003.

81. Zhi, L., Miedema, S.A., Vlasblom, W.J., Verheul, C.H., "Modeling and Simulation of the Dynamic Behaviour of TSHD's Suction Pipe System by using Adams". CHIDA Dredging Days, Shanghai, China, november 2003.

82. Miedema, S.A., "The Existence of Kinematic Wedges at Large Cutting Angles". CHIDA Dredging Days, Shanghai, China, november 2003.

83. Miedema, S.A., Lu, Z., Matousek, V., "Numerical Simulation of the Development of Density Waves in a Long Pipeline and the Dynamic System Behaviour". Terra et Aqua 93, December 2003.

84. Miedema, S.A. & Frijters, D.D.J., "The wedge mechanism for cutting of water saturated sand at large cutting angles". WODCON XVII, September 2004, Hamburg Germany.

85. Verheul, O. & Vercruijsse, P.M. & Miedema, S.A., "The development of a concept for accurate and efficient dredging at great water depths". WODCON XVII, September 2004, Hamburg Germany.

86. Miedema, S.A., "THE CUTTING MECHANISMS OF WATER SATURATED SAND AT SMALL AND LARGE CUTTING ANGLES". International Conference on Coastal Infrastructure Development - Challenges in the 21st Century. HongKong, november 2004.

87. Ir. M. Zwanenburg , Dr. Ir. S.A. Miedema , Ir J.D. Holstein , Prof.ir. W.J.Vlasblom, "REDUCING THE DAMAGE TO THE SEA FLOOR WHEN DREDGING COCKLE SHELLS". WEDAXXIV & TAMU36, Orlando, Florida, USA, July 2004.

88. Verheul, O. & Vercruijsse, P.M. & Miedema, S.A., "A new concept for accurate and efficient dredging in deep water". Ports & Dredging, IHC, 2005, E163.

89. Miedema, S.A., "Scrapped?". Dredging & Port Construction, September 2005. 90. Miedema, S.A. & Vlasblom, W.J., " Bureaustudie Overvloeiverliezen". In opdracht

van Havenbedrijf Rotterdam, September 2005, Confidential. 91. He, J., Miedema, S.A. & Vlasblom, W.J., "FEM Analyses Of Cutting Of Anisotropic

Densely Compacted and Saturated Sand", WEDAXXV & TAMU37, New Orleans, USA, June 2005.

92. Miedema, S.A., "The Cutting of Water Saturated Sand, the FINAL Solution". WEDAXXV & TAMU37, New Orleans, USA, June 2005.

93. Miedema, S.A. & Massie, W., "Selfassesment MSc Offshore Engineering", Delft University of Technology, October 2005.

94. Miedema, S.A., "THE CUTTING OF WATER SATURATED SAND, THE SOLUTION". CEDA African Section: Dredging Days 2006 - Protection of the coastline, dredging sustainable development, Nov. 1-3, Tangiers, Morocco.

95. Miedema, S.A., "La solution de prélèvement par désagrégation du sable saturé en eau". CEDA African Section: Dredging Days 2006 - Protection of the coastline, dredging sustainable development, Nov. 1-3, Tangiers, Morocco.

96. Miedema, S.A. & Vlasblom, W.J., "THE CLOSING PROCESS OF CLAMSHELL DREDGES IN WATER-SATURATED SAND". CEDA African Section: Dredging Days 2006 - Protection of the coastline, dredging sustainable development, Nov. 1-3, Tangiers, Morocco.

97. Miedema, S.A. & Vlasblom, W.J., "Le processus de fermeture des dragues à benne preneuse en sable saturé". CEDA African Section: Dredging Days 2006 - Protection of the coastline, dredging sustainable development, Nov. 1-3, Tangiers, Morocco.

98. Miedema, S.A. "THE CUTTING OF WATER SATURATED SAND, THE SOLUTION". The 2nd China Dredging Association International Conference & Exhibition, themed 'Dredging and Sustainable Development' and in Guangzhou, China, May 17-18 2006.

99. Ma, Y, Ni, F. & Miedema, S.A., "Calculation of the Blade Cutting Force for small Cutting Angles based on MATLAB". The 2nd China Dredging Association

International Conference & Exhibition, themed 'Dredging and Sustainable Development' and in Guangzhou, China, May 17-18 2006.

100. ,"" (download). The 2nd China Dredging

Association International Conference & Exhibition, themed 'Dredging and Sustainable Development' and in Guangzhou, China, May 17-18 2006.

101. Miedema, S.A. , Kerkvliet, J., Strijbis, D., Jonkman, B., Hatert, M. v/d, "THE DIGGING AND HOLDING CAPACITY OF ANCHORS". WEDA XXVI AND TAMU 38, San Diego, California, June 25-28, 2006.

102. Schols, V., Klaver, Th., Pettitt, M., Ubuan, Chr., Miedema, S.A., Hemmes, K. & Vlasblom, W.J., "A FEASIBILITY STUDY ON THE APPLICATION OF FUEL CELLS IN OIL AND GAS SURFACE PRODUCTION FACILITIES". Proceedings of FUELCELL2006, The 4th International Conference on FUEL CELL SCIENCE, ENGINEERING and TECHNOLOGY, June 19-21, 2006, Irvine, CA.

103. Miedema, S.A., "Polytechnisch Zakboek 51ste druk, Hoofdstuk G: Werktuigbouwkunde", pG1-G88, Reed Business Information, ISBN-10: 90.6228.613.5, ISBN-13: 978.90.6228.613.3. Redactie: Fortuin, J.B., van Herwijnen, F., Leijendeckers, P.H.H., de Roeck, G. & Schwippert, G.A.

104. MA Ya-sheng, NI Fu-sheng, S.A. Miedema, "Mechanical Model of Water Saturated Sand Cutting at Blade Large Cutting Angles", Journal of Hohai University Changzhou, ISSN 1009-1130, CN 32-1591, 2006. 绞刀片大角度切削水饱和沙的力学模型, 马亚生[1] 倪福生[1] S.A.Miedema[2], 《河海大学常州分校学报》-2006年20卷3期 -59-61页

105. Miedema, S.A., Lager, G.H.G., Kerkvliet, J., “An Overview of Drag Embedded Anchor Holding Capacity for Dredging and Offshore Applications”. WODCON, Orlando, USA, 2007.

106. Miedema, S.A., Rhee, C. van, “A SENSITIVITY ANALYSIS ON THE EFFECTS OF DIMENSIONS AND GEOMETRY OF TRAILING SUCTION HOPPER DREDGES”. WODCON ORLANDO, USA, 2007.

107. Miedema, S.A., Bookreview: Useless arithmetic, why environmental scientists can't predict the future, by Orrin H. Pilkey & Linda Pilkey-Jarvis. Terra et Aqua 108, September 2007, IADC, The Hague, Netherlands.

108. Miedema, S.A., Bookreview: The rock manual: The use of rock in hydraulic engineering, by CIRIA, CUR, CETMEF. Terra et Aqua 110, March 2008, IADC, The Hague, Netherlands.

109. Miedema, S.A., "An Analytical Method To Determine Scour". WEDA XXVIII & Texas A&M 39. St. Louis, USA, June 8-11, 2008.

110. Miedema, S.A., "A Sensitivity Analysis Of The Production Of Clamshells". WEDA XXVIII & Texas A&M 39. St. Louis, USA, June 8-11, 2008.

111. Miedema, S.A., "An Analytical Approach To The Sedimentation Process In Trailing Suction Hopper Dredgers". Terra et Aqua 112, September 2008, IADC, The Hague, Netherlands.

112. Hofstra, C.F., & Rhee, C. van, & Miedema, S.A. & Talmon, A.M., "On The Particle Trajectories In Dredge Pump Impellers". 14th International Conference Transport & Sedimentation Of Solid Particles. June 23-27 2008, St. Petersburg, Russia.

113. Miedema, S.A., "A Sensitivity Analysis Of The Production Of Clamshells". WEDA Journal of Dredging Engineering, December 2008.

114. Miedema, S.A., "New Developments Of Cutting Theories With Respect To Dredging, The Cutting Of Clay And Rock". WEDA XXIX & Texas A&M 40. Phoenix Arizona, USA, June 14-17 2009.

115. Miedema, S.A., "A Sensitivity Analysis Of The Scaling Of TSHD's". WEDA XXIX & Texas A&M 40. Phoenix Arizona, USA, June 14-17 2009.

116. Liu, Z., Ni, F., Miedema, S.A., “Optimized design method for TSHD’s swell compensator, basing on modelling and simulation”. International Conference on Industrial Mechatronics and Automation, pp. 48-52. Chengdu, China, May 15-16, 2009.

117. Miedema, S.A., "The effect of the bed rise velocity on the sedimentation process in hopper dredges". Journal of Dredging Engineering, Vol. 10, No. 1 , 10-31, 2009.

118. Miedema, S.A., “New developments of cutting theories with respect to offshore applications, the cutting of sand, clay and rock”. ISOPE 2010, Beijing China, June 2010.

119. Miedema, S.A., “The influence of the strain rate on cutting processes”. ISOPE 2010, Beijing China, June 2010.

120. Ramsdell, R.C., Miedema, S.A., “Hydraulic transport of sand/shell mixtures”. WODCON XIX, Beijing China, September 2010.

121. Abdeli, M., Miedema, S.A., Schott, D., Alvarez Grima, M., “The application of discrete element modeling in dredging”. WODCON XIX, Beijing China, September 2010.

122. Hofstra, C.F., Miedema, S.A., Rhee, C. van, “Particle trajectories near impeller blades in centrifugal pumps. WODCON XIX, Beijing China, September 2010.

123. Miedema, S.A., “Constructing the Shields curve, a new theoretical approach and its applications”. WODCON XIX, Beijing China, September 2010.

124. Miedema, S.A., “The effect of the bed rise velocity on the sedimentation process in hopper dredges”. WODCON XIX, Beijing China, September 2010.