MXPA97008159A - Apparatus and method for evaluating an ama bed - Google Patents

Abstract

The present invention relates to an apparatus for producing measurement data capable of characterizing a burial path in a seabed floor, the apparatus comprising: an evaluation means including a body member for inclusion in a burial apparatus capable of buried in a seabed floor along a path, the evaluation device serving to indicate the position on the ground of a point in either the burial apparatus and the body member during the burial, to allow the tracing of the trajectory of the point, including the evaluation means a measuring means that responds to the movement of the burial apparatus during the burial, to measure the displacement of the point that moves along the trajectory

Description

APPARATUS AND METHOD FOR EVALUATING A MOORING BED The present invention relates to an apparatus and method for evaluating a mooring bed. When evaluating drag anchor anchors as anchoring elements in a distribution mooring to deploy in a submerged marine mooring bed, it is desirable to know the engineering properties of the soil in the mooring bed at points coordinate in the trajectory that is it expects to follow each anchor as it is buried in the mooring bed in response to a large force applied substantially horizontally in relation to its traction cable. In terms of anchor-ear lengths, it has been shown that trawling anchors of the most modern designs follow a trajectory that penetrates up to five lengths of ears below the surface of a sea bed of normally consolidated clay which frequently occurs in a shear strength gradient of 1.6 kPa /, when pulled by a chain cable. When pulled by a wire rope with a diameter of one third of the diameter of a circumscribing notional cylinder containing the chain cable, the trajectory penetrates up to five ear lengths. In the case of a trailing anchor of the largest size currently in use, having an ear length of approximately 6 meters and pulled by a wire rope cable, the burial path forms a curve that decreases progressively as to its inclination in relation to the horizontal line from 50 * at the initial point of penetration until it becomes horizontal to a maximum anchor holding capacity of approximately 40 times the weight of the anchor when the anchor has moved approximately 300 meters horizontally and buried approximately 54 meters vertically. Accordingly, it is advantageous to have engineering data for the floor of the mooring bed on a vertical area that is at least 300 meters long along the seabed surface and a depth of 54 meters in each of up to 12 meters. widely spaced locations in a distributed mooring site to allow each ia path to be predicted. In the past, engineering data for deeply submerged bedding floors have been derived from remote cutting blade tests and remote cone penetrometer tests evaluated in combination with laboratory tests performed on soil samples taken from a small number. of drilling carried out in the mooring bed at selected locations on the site. These tests and samples are made within a range of depths of up to 60 meters or more below the seabed surface in each of the locations chosen to provide a unique set of soil data for the site. However, due to exorbitantly high costs involved in the development of such investigations, the number of test and sampling locations chosen is invariably minimized. One disadvantage is that the interpolation of the small number of data points on a large site area leaves a large margin of uncertainty among the chosen locations. This, in turn, provides considerable uncertainty in relation to the prediction of the performance and trajectory of a drag anchor in the mooring bed floor between these locations. Also in the past, anchor burial trajectories were measured. Horizontal coordinates in a trajectory were determined by obtaining the approximate horizontal displacements of the anchor by measuring the corresponding horizontal displacements of a given point in a horizontal part of its traction cable that was buried under the surface of the seabed . Corresponding vertical coordinates were determined either directly or by using a thin cable fixed on the anchor and pulled vertically to measure its penetration depth below the surface of the seabed, or indirectly through the use of a pressure sensor mounted on the anchor to measure the static pressure of the water column from the anchor buried to the sea surface through a flexible tube used to carry the water column from the surface of the seabed to the anchor. In the case of the direct method, the disadvantages of these past measurement methods include the lack of uncertainty that the thin wire has been pulled sufficiently densely so that it truly becomes on the ground without affecting the buried anchor and the need for numerous repetitions. of this operation. In the case of the indirect method, the disadvantages of these past measurement methods include uncertainty due to pressure fluctuations caused by long sea surface surges and occlusion of the water column conductor tube by wall collapse due to pressure from the soil, folds or the entry of soil at its end 1 ibre. It is an object of the present invention to provide a pull-in burial apparatus capable of establishing a deep burial trajectory in a seabed floor while producing a horizontal drag to the drive embedment substantially less than that produced by an embedment anchor. drag and its cable while establishing such a path in the ground. Another object of the present invention is to provide an apparatus for producing measurement data capable of characterizing a burial path traced by a point in a burial apparatus that is buried in a tie-bed floor. Another object of the present invention is to provide an apparatus for measuring an engineering characteristic of said floor at characteristic points of said path treated by said point in said burial apparatus. Another object of the present invention is to provide a method for evaluating the anchoring capacity of a marine mooring bed by interpreting the shape of a burial trajectory produced there by said trailing embedding burial apparatus. According to a first aspect of the present invention, an apparatus for producing measurement data capable of characterizing a burial path traced on a seabed floor comprises an evaluation device that includes a body member that can be adapted or incorporated into a burial apparatus capable of being buried in a seabed floor along a path, said evaluation device indicating the position on the ground of a point in said burial apparatus or body member during burial to allow tracing of the trajectory of said point, said evaluation device includes a measuring device that responds to the movement of the burial apparatus to measure the displacement of said point that moves along said path. In accordance with a second aspect of the present invention, an apparatus for establishing and characterizing a burial path in a seabed floor comprises a feature measuring apparatus in accordance with the aforementioned first aspect included in a burial apparatus that includes a wire rope pulling cable fixed on one end of an elongated shaft member, another end of which is fixed on an ear member for dragging into said ground along a path that is in a vertical plane containing said rod member, wherein the projected minimum area of said rod member and said ear member projected in a particular direction in said plane does not exceed 20% (and preferably does not exceed 1014) of the corresponding projected maximum area projected at angles straight in relation to that direction in that plane. Preferably, said measuring device serves to measure a distance along the path separating two spaced points and, in addition, an additional parameter comprising any of the following: a) the inclination of the trajectory at a point in the trajectory; and b) the horizontal or vertical displacement of said point in relation to a data. Preferably, said means for measuring the distance along said trajectory separating two points is included in said body member. Preferably, said body member is elongated and hollow and is connected in a pivot on said point in said burial apparatus so that it can be aligned axially in said path. Preferably there is provided a line member fixed on said body member which can be profiled behind said body member to coincide with said trajectory as the burial apparatus is buried in the floor of the mooring bed. Preferably, said body member has an internal compartment containing a storage device that stores said line member. Preferably, said line member at a remote end of its attachment point with said body member is fixed on a resistive member external to said body member that resists penetration and remains on the surface of the tie-down bed when said member The body member moves along said path so that the line member is extracted from the body member to coincide with said path. Preferably, said device for measuring distance. between points along said path is driving by said line member as it leaves said body member. Preferably, said device for measuring the distance between points along said path comprises a pulley wheel mounted on said body member and that can rotate due to the passage of said line member when it is extracted from said body member and a magnet rotating arbitrarily due to said pulley wheel for activating a magnetic field sensing switch in said body member to provide an electrical impulse output defining successive points of known fixed separation in said line member occupying said path according to said pulley wheel is rotated by the pulley member that is extracted. Preferably said measuring device for providing data from which the angle of inclination of the trajectory at a point in the path can be determined comprises an electrical inclining device rigidly fixed on said body member whose output is sampled using the pulse defining points from said magnetic field detection circuit in said body member. Preferably, the inclinometer device comprises an accelerometer arranged to provide an output voltage proportional to the product of the gravitational acceleration of the earth and the cosine of the angle of inclination of the accelerometer relative to a horizontal line. Preferably the body member contains a data logger electrically activated to store inclination angle measurement data of all points defined by known fixed separation pulse along said line member occupying said path. Preferably said storage device for said line member comprises a helical icoidal helical coil wound with the line member that can be extracted from the inner part of the coil. Preferably, said internal compound containing said storage device is filled with a fatty substance. Preferably said behavior is closed by means of a sealed displacement piston pierced by a narrow fitting hole around the line member exiting therethrough so that the movement induced by the pressure of the piston as the line member leaves eliminates the pressure differentials through the piston and thus prevents the penetration of material from the bedding floor in said compartment. Preferably, the line member comprises an electric cable which additionally serves to conduct data by means of electrical signals from the body member along the path of the path to an acoustic responder adjacent to the mooring bed surface whereby the characteristic data of the path can be transmitted to a receiver adjacent to the surface of the ma r. Furthermore, preferably said device for measuring the distance between points along said trajectory comprises turbine fins mounted on an axis projecting from said body member and a magnet fixed on said axis and rotating arbitally by the action of said axis for activating a magnetic field sensing switch in said body member to provide an electrical pulse output defining successive known fixed separation points in said trajectory as said axis rotates due to the impact of the ground on the fins by the movement of said member body through the ground along said path. Preferably, said apparatus includes a device for measuring a soil parameter such as resistance to penetration.

Preferably, said device for measuring a floor parameter comprises an electrically readable penetrometer arranged to measure the resistance to penetration of said floor. According to a further aspect of the present invention, a method for producing data to evaluate the anchoring capacity of a seabed floor in a mooring seabed comprises: a) placing in the mooring bed of an apparatus for establishing and characterizing a burial path in said ground and pulling substantially horizontally on its wire until a desired part of a burial path has been recorded; b > display a trace of said recorded trajectory; c) scrutinize said footprint to identify points where rapid fluctuations of slope occur which indicate rapid changes of soil parameters, in a transverse manner in relation to the interfaces between layers, or hooking in obstructions all of which influences an anchor capacity rating in accordance with the mooring bed. In the following, embodiments of the present invention will be described by way of example with reference to the following drawings in which: Figure 1 is a representation (not to scale) of a mooring bed evaluation apparatus in use; Figure 2 is a part of a sectional side view of a burial apparatus with a path characteristic measuring apparatus mounted on said burial apparatus; Figure 3 is a bottom plan view of the apparatus of Figure 2 showing its projected maximum area; Figure 4 is a front view of the apparatus of Figure 2 seen in a direction at right angles in relation to the direction of observation of Figure 3 where a projected minimum area is observed; Figure 5 is a partial sectional view of a path characteristic measuring apparatus and part of the burial apparatus shown in Figure 2; Figure 6 is a front view of the path characteristic measuring apparatus; Figure 7 is a sectional side view of an alternative tail portion for the path characteristic measurement apparatus shown in Figure 5. With reference to Figure 1, an apparatus 1 for establishing and characterizing a burial path 2 in a floor of a seabed 3 comprises a path feature measuring apparatus 4 connected to a point P in a burial apparatus 5 formed by a relatively thin wire rope 6 arranged pivotably on one end of an antler 7, the other end of said shank is fixed on an ear 8 for the driving embedment burial through a seabed surface 9 on seabed floor 3 when it is pulled horizontally by a sea vessel 10 on the surface of the sea 11. The path 2 is in a vertical plane containing a rod 7 and starts at the surface of the seabed 9 at a pitch angle of approximately 50 ° in relation the horizontal Path 2 progressively decreases in its slope until it is horizontal at a depth of embedment D below the surface of the seabed 9. In multiple terms of the length L of the ear 8, in a normally consolidated gradient clay soil of shear strength of 1.okPa / etro, depth D may be within a range of 9L to 18L and path 2 will become horizontal after device 5 has been dragged over a distance of approximately 40L to SOL measured horizontally. With reference to figures 1 to 4, the burial apparatus 5 is constructed with minimum projected area present for each of its components when viewed in a forward direction F (figure 2). The ear 8, of length L, has a projected maximum area A (Fig. 3) when viewed at right angles in relation to the direction F in the longitudinal center plane XX (Fig. 3 and 4) containing a shank 7. The diameter of the rope, wire 6 does not exceed A / 24L and preferably does not exceed A / 37L. A rod 7 and ear 8 have an aerodynamic shape and have sharp front cutting edges to minimize resistance to forward travel on the ground 3. The minimum projected area in direction F of a comb 7 and ear 8 combined does not exceed 0.2A and preferably does not exceed 0.12A. The projected minimum area of the direction F of a rod 7 na exceeds 0.2A and preferably does not exceed 0.12A. Earcuts 8 in planes parallel to plane X-X substantially have a wedge shape with a front included angle not greater than 10 ° and preferably not greater than 6β. The maximum depth of cuts adjacent to the X-X plane does not exceed 0.15L and preferably does not exceed 0.07L. These dimensional limitations in relation to the burial apparatus 5 allow it to penetrate very deeply to depths between 9L and 18L below surface 9 of the seabed in the aforementioned soft clay soil for a relatively low horizontal force applied to the rope of 6 wire by a maritime ship 10. With reference to figures 2, 3 and 4, an apparatus for measuring trajectories 4 includes a hollow closed cylindrical metal body 12 having a front conical nose portion 13 fixed on a nail 14 protruding from starting from a front part of the inner surface of the ear 8 of the burial apparatus 5 by means of a pivot 15 at a point P which allows the body 12 to automatically align with the trajectory 2 due to the touch against the unprepared soil. With further reference to Figures 5 and 6, a tubular probe 16 is fixed on a conical nose portion 13 carrying a cone-shaped penetrometer 17 which is a known industrial standard in the unaltered soil before the body 12, the cone The penetrometer is axially symmetric. The penetrometer 17 provides an electrical output proportional to the soil pressure against it. A turbine rotor 18 of the floor flow, with four equally spaced radial fins 19, is mounted on an axle 20 projecting axially from the rear conical tail part 21 of the body 12. The axle 20 also extends forward in a inner cavity 22 inside the body 12. The area swept by the fins of the turbine 19 exceeds the maximum cutting area of the body 12 sufficiently to ensure that the passing floor 3 touches the fin 19 to rotate the rotor 18 and the shaft 20 when the point P moves along the path 2 (FIG. 2) due to the pulling force on the wire cable 6. The shaft 20 is equipped with a shaft seal 23 and support bushings 24 forced into the part of tail 21 of the body 12. A disk 25 is mounted on the shaft 20 in the cavity 22! and carries a magnet 26. A magnetic switch 27 of Effect Hll is mounted within the cavity 22 adjacent the disk 25 such that the transit of the magnet 26 past the switch 27 as the shaft 20 rotates produces an electrical pulse once for each revolution in the turbine rotor 18. This electrical impulse therefore indicates the successive arrival of equally spaced points in the trajectory 2 with the interval determined by the step chosen for the turbine wings 19. A known voltage output accelerometer acts as a sensitive inclinometer 28, a data logger 29, and a power supply 30 per battery is mounted in a cavity 22 of the body 12. An incl. Intro 28 is mounted with its vertical axis being in the longitudinal plane of the burial apparatus 5 containing a shaft 7 and with its horizontal axis parallel to the axis of the body 12. The inclinometer (accelerometer) 28 provides a voltage output proportional to the product of the gravitational acceleration g of the earth and the cosine of the theta angle (figure 1) of inclination of its horizontal axis and the axis of the body 12 with the horizontal. Since g is constant, the output of inclinometer 28 is proportional to "eos theta". The output of the inclinometer 28 and the cone penetrometer 17 are sampled by the data logger 29 and stored at the arrival of each asynchronous pulse indicating position from the switch 27. A wire rope 6 is constructed to include cables electrical conductors 53 (FIG. 2) to allow equipment in ship 10 to receive and store the sampled outputs as stored in data register 29. This allows the sampled outputs to be monitored as the trajectory is being established., with the data logger 29 acting as security against loss of data due to a possible affectation of the signal path between the body 12 and the equipment in the marine vessel 10. An electrical splicing cable 52 is installed for the burial apparatus 5 which leads from an electrical connector 54 in the lead wires 53 in the wire rope 6 through a rod 7, ear 8, and nail 14, to connect with the data logger 29 in the body 12. Referring now to the embodiment of Figure 7, an alternative cylindrical tail portion 31 is installed on the body 12 instead of the tail portion 21 of Figure 5 and the device of Figure 7 has a slightly different operation from the operation of the device of figure 5 as will be explained later. A shaft 32 is mounted on a front wall 33 of a tail portion 31 by means of support bushing 34 and shaft seal 35 and protrudes into a cavity 22. Disk 36 is mounted on one end of shaft 32 within a cavity 22 and carries a magnet 37 to drive a Hall Effect switch 27 as described above. A beveled gear 38 is mounted on the other end of the shaft 32 in a cavity filled with grease 39 within the tail portion 31. A beveled gear 40 engages with the beveled gear 38 and is fixed coaxially on a pulley wheel 41. The aft end of the cavity 39 is closed by a piston 42 which can slide axially within a cylindrical tail portion 31 and it is sealed by sliding seals 43. The cavity 39 contains a hollow cylindrical bobbin 44 of twine cord 45 which leaves a hollow interior space 46 inside a spool 44 and passes twice around the pulley wheel 41 before leaving the cavity 39 through a nozzle 47 in the piston 42 to a fixing point 48 on a removable end cap 49 placed under pressure on the aft end of the tail portion 31. An end cap 49 has a flange 50 of soil flow stop extending beyond the outer diameter of the cylindrical tail portion 31, which serves to pull the end cap 49 out of the tail portion 31 when the soil strikes against it . The diameter of the pulley wheel 41 is chosen to provide two disc revolutions 36 for each meter of twine cord 45 passing over the pulley wheel 41. Accordingly, a disc 36 rotates twice for each meter of body movement 12. along a trajectory 2 co or in the case of the disc 25 of the tail portion 21 of Figure 5. An acoustic responder 51 can be fixed on the end cap 49 and the twine cord 45 can be replaced by an electrical conductor flexible thin multi-strand connected to a data recorder 29 at one end and an acoustic responder 51 at the other end. The use, now referring to Figure 1, a burial apparatus 5 with trajectory measuring apparatus 4 fixed on said burial apparatus is placed on a surface of the bottom of the sea 9 in a mooring bed, of normally consolidated clay occurs frequently from a shear strength gradient of 1.6 kPa / meter, in water depth h, by a sea ship 10 that applies horizontal traction on the wire rope 6 to cause the ear 8 of the apparatus 5 to be pulled forward and penetrate through surface 9 of the seabed. Ground pressure forces on the ear 8 and resistance forces on the rod 7 and the wire rope 6 force the ear 8 to follow a curved path 2 traced by a point P on the ear 8. The trajectory 2 has an inclination approximately 50 ° in relation to a horizontal line initially and gradually decreases its inclination until reaching a horizontal level at a great depth of penetration D below surface 9 of the seabed of approximately 9 to 18 times the length L of the ear 8 following a horizontal movement of approximately SUN. The body 12 of the apparatus 4 is held in axial alignment with trajectory by the ground forces causing its rotation about a point P such that the measurement of the inclination of the body 12 by an inclinometer 28 is also a measurement of the inclination local path 2. Referring now to figures 2 to 6As the body 12 moves through the ground 3, a turbine rotor 18 rotates due to the impact of the ground on the fins of a rotor 19 which in turn rotates an axis 20 and disk 25. As a magnet 26 rotates in a disc 25 past the Hall Effect switch 27, an electrical pulse is produced which causes a data logger 29 to display and store the electrical output of a cone penetrometer 17 and an inclinometer 28. The passage of the fins 19 it chooses to provide two revolutions of turbine rotor 18 for each meter of body movement 12 along path 2. Therefore, for a trajectory 2 of a length of approximately 30 meters, measurements of the penetration resistance and Path tilt is performed and stored at 600 points on trajectory 2 each separated by half a meter. These measurements are also received and stored by a team in a maritime ship 10 through the electric conductors 53 included in the wire rope 6. The horizontal component "delta x" and the vertical component "delta y" of a "delta s" increment of distance between two points Pl and P2 indicated by pulses in trajectory 2 are then determined by multiplying "delta s" (chosen as 0.5 meter, in this case) by the cosine and the sine, respectively, of the mean angle theta of inclination of the body 12 in relation to the horizontal in these points (figure 1). Therefore, "delta x" = "delta s" "eos theta" and "delta y" = "delta s" "os theta" = 0.5 sintheta. This allows the coordinates of any point P (x, y) in a set of points spaced by the interval ds in path 2 to be established by computerized summation as P (SIGMA "delta x", SI6MA "delta y") and can visualize yourself graphically The shear strength values of the soil are calculated for each point indicated per pulse from the sampled cone penetrometer output 17 and are visualized together with the plotted curve of path 2. Referring now to FIG. portion of tail 31 in use has end cap 49 pushed by the impact on the ground at flange 50 as body 12 is pulled through the surface of seabed 9 and along path 2. End cap 49 is too large to be pulled on the seabed floor 3 by the string 45 and therefore remains on the surface 9 of the floor 3 of the seabed (Figure 1) and consequently causes the string 45 to come out of the nozzle 47 on the piston 42 to be located in the path 2. The existing line 45 grips and rotates a pulley wheel 41 which, through the bevelled gears 38, 40 and the shaft 32 rotate a disc 36 and rotate a magnet 37 more beyond the Hall Effect switch 27 to produce activation pulses as described above. Meanwhile, the piston 42 moves in a cavity 39 below the external pressure of the floor to increase the pressure of the grease inside as the cord 45 is removed. A pressure differential 0 is therefore maintained through the piston 42 which inhibits the entry of soil 3 into the cavity 39 through the nozzle 47. If the string 45 is replaced by a thin multi-strand flexible electrical conductor, the data stored in a data recorder 29 is transmitted to an acoustic responder 51 set on the end cap 49 on the surface 9 of the seabed for transmission to an acoustic reflector located on a maritime ship 10 (figure 1) as an alternative to having an electrical conductor influenced on the wire rope 6 (figure 1). The objectives of the present invention are therefore realized by burying the apparatus 5 providing a value of D within the range of 9L to 18L in a clay normally consolidated with a shear strength gradient of 1.6 kPa / for a pulling force horizontal relatively low, by characterizing trajectory 2, and by determining a soil parameter along with this trajectory. Another objective is achieved by observing the shape of a particular trajectory and observing that sudden changes in the slope indicate a deviation from uniform soil conditions such as discontinuities of layer formation, and the presence of obstructions. The anchoring capacity is then evaluated from the number and importance of the deviations from a soft curve observed in the characterized trajectory. The described apparatus and method of use can therefore be applied to evaluate the suitability of particular locations in a tie-down bed for the deployment of trailing cast-in anchors having a large horizontal resistance to movement without the need for costly drilling.

Obviously modifications can be made. Particularly, the measuring device for determining the horizontal and vertical displacements of a moving point in the trajectory may be different, as well as the device for determining the trajectory inclination at a point in the trajectory. In addition, the device for measuring the resistance to soil penetration could be different from that described above. For example, a beveled disc, or part of it, located parallel to a plane of symmetry of the burial apparatus could replace the axially symmetric cone cone penetrometer standard in the known industry. This disc will allow measurements of resistance to penetration at different angles of soil flow direction without the need to pivot the rheometer penis to bring it into axial alignment with the direction of soil flow. In addition, known devices for measuring surface friction and pore pressures can be included in the apparatus to provide corresponding data for points in the measured path. Additionally, as an alternative to the movement measuring device comprising the turbine wheel 19 or the string 24 (with associated equipment), an accelerometer can be used, so by means of the use of an integration process, the displacement of a point in the burial member 5 moving along the path 3 and the position of said moving point in the ground can be evaluated to provide a tracing of said path in the ground.

Claims (25)

1. CLAIMS 1. An apparatus for producing measurement data capable of characterizing a buried burial path in a seabed floor comprising an evaluation device that injects a body member that can be installed or incorporated into a burial apparatus capable of buried in a floor of the seabed along a path, said evaluation device indicates the position on the ground of a point in said burial apparatus or body member during the burial to allow tracing the trajectory of said point , said evaluation device includes measurement means that respond to the movement of the burial apparatus to measure the displacement of said point that moves along said trajectory.
2. 2. An apparatus for establishing and characterizing a burial path in a seafloor floor comprising an apparatus that measures the characteristics of claim 1 included in a burial apparatus that includes a wire rope pull wire fixed on an end of an elongated shaft member whose other end is fixed to an ear member for dragging into said ground along a path that is located in a vertical plane containing said horn member, where the minimum area projected from said shaft member and said ear member projecting in a particular direction in said plane does not exceed 20 '/ del of the maximum projected area projecting at right angles relative to said direction in said plane.
3. 3. An apparatus according to claim 1 or 2, wherein said measuring device serves to measure a distance along the path that separates two points spaced in that path and additionally an additional parameter comprising any of the following: a) inclination of the trajectory at a point in the trajectory; and b) the horizontal or vertical displacement of said point in relation to a data.
4. 4. An apparatus according to claim 1, 2 or 3, wherein said device for measuring the distance along said trajectory separating two points on said path is received in said body member.
5. 5. An apparatus according to claim 1, wherein said body member is elongate and hollow and rotatably connected to said point in said burial apparatus so that it can be aligned axially in said path.
6. 6. An apparatus in accordance with any of the above indications wherein a line member fixed on said body member is provided, which can be removed behind said body member to coincide with said trajectory as the burial apparatus is buried in the body. floor of the mooring bed.
7. 7. An apparatus according to claim 6, wherein said body member has an internal compartment containing a storage device storing said line member.
8. 8. An apparatus according to claim as claimed in claim 6 or 7, wherein said line member at a remote end of its attachment to said body member is attached to a resistive member external to said body member that resists penetration. on the surface of the mooring bed and remains on said surface when said body member moves along said trajectory whereby the line member is extruded from the body member to coinid with said rajectory.
9. An apparatus according to any of claims 6 to 8, wherein said device for measuring the distance between points along said path is driven by said line member as it exits said body member.
10. 10. An apparatus according to claim as claimed in any of claims 6 to 9, wherein said device for measuring the distance between points along said path comprises a pulley wheel mounted on said body member and rotating by the passage therein of said line member as it is extracted from said body member and a magnet which rotates organically; by the action of said pulley wheel to activate a magnetic field detection switch in said body member to provide an electrical use output defining successive known fixed separation points in said line member occupying said trajectory according to said wheel of Pulley is rotated by the departing line member.
11. 11. An apparatus according to claim 3, wherein said measuring device for providing data from which the angle of inclination of the trajectory can be determined at a point in the path comprises an electrical inclinometer device rigidly fixed on said body member whose output is sampled using the pulse of defining points from said magnetic field detection circuit in said body member.
12. 12. An apparatus as claimed in claim 11, wherein the inclinometer device comprises an accelerometer arranged to provide an output voltage proportional to the product of the acceleration of the earth's gravity and the cosine of the angle of 50 inclination of the accelerometer in relation to a horizontal line.
13. 13. An apparatus in accordance with claimed in any of the indications rei 11 or 12, wherein the body member contains an electrically activated data logger to store the data of measurement angle of all points defined by pulse separation known fixed along said line member occupying said trajectory.
14. 14. The apparatus according to claim 7, wherein said storage device for said line member comprises a wound coil 1 wound with the line member that can be extracted from the inner part of a coil.
15. 15. An apparatus according to claim 7, wherein said internal compartment containing said storage device is filled with a substance similar to grease.
16. 16. An apparatus according to claim 7, wherein said compartment is closed by a sealed sliding piston pierced by a narrow fitting hole around the line member exiting through it so that the movement induced by the pressure of the piston as the line member exits eliminates the pressure differentials through the piston and thus prevents the penetration of material from the floor of the tie-down bed into said compartment.
17. 17. Apparatus according to claim 6, wherein the line member comprises an electric cable that further serves to conduct data by means of electrical signals from the body member along the path of the path to a acoustic response adjacent to the mooring bed surface so that the data characterizing the trajectory can be transmitted to 10 a receiver adjacent to the sea surface.
18. 18. An apparatus according to claim 3, wherein said device for measuring the distance between points along said path comprises turbine fins mounted on an axis projecting from said member. 15 of body and a device that responds to the rotation of said shaft to indicate successive points of known fixed separation in said trajectory as said axis rotates by means of the impact of the ground in said fins due to the movement of said body member through the ground to 20 along said path.
19. 19. An apparatus according to claim 18, wherein said response device comprises a magnet fixed on said axis and which rotates orbitally by said axis to activate a magnetic field detection switch. 25 in said body member to define an electrical pulse output defining said successive points.
20. 20. An apparatus in accordance with any of the above indications which includes a device for measuring the soil such as resistance to penetration.
21. 21. An apparatus according to claim 20, wherein said device for measuring a soil parameter. -comprises an electrically readable penetrometer arranged to measure the resistance to penetration of said soil.
22. 22. An apparatus according to claim 2, wherein said projected minimum area of said horn member exceeds 10/5 of said corresponding maximum projected area projecting at right angles toward said direction in said plane.
23. 23. A method for producing data for assessing the ability of anchoring a seabed floor in marine mooring bed comprising: a) placing in the mooring bed an apparatus for establishing and characterizing a burial trajectory in said ground and traction substantially horizontally on its wire until a desired portion of burial path has been recorded; b) present a trace of said registered trajectory; c) scrutinize this footprint to identify points where fast dependent fluctuations occur that indicate rapid changes of soil parameters, transverse to interphase interfaces, or snagging in obstructions all of which influence a classification of anchorage capacity that is assigned to the bed of ama r ns.
24. 24. A tie-bed evaluation apparatus substantially as described above with reference to Figures 1 to 6 of the accompanying drawings or to these figures in accordance with that modified by Figure 7.
25. 25. A method for producing data to evaluate the anchoring capacity of a seabed floor in a marine mooring bed in accordance with that claimed in the indication 21 and substantially co or described above.