FI115071B - Method and apparatus for measuring distance - Google Patents

Description

115071

METHOD AND APPARATUS FOR MEASURING DISTANCE

The invention relates to a method for measuring distance, in particular to a pile machine submersible submersible submersible submersible submersible, during which the pile submersion is automatically determined by a measuring device placed in connection with the pile molding machine. The invention also relates to an apparatus for applying the method of claim 1, wherein the apparatus comprises a measurement unit for processing the measurement results obtained by the measuring apparatus.

Various buildings and structures are built on pile embedded in the ground. Piling is usually done by hitting or twisting. The power and energy required to immerse a submerged pile increases as the pile submersion increases. For this reason, for example, the bearing capacity of a pile to be immersed with a pile hammer can be determined by measuring the impact energy of the pile hammer and the corresponding change in pile displacement. In current piling hammers it is possible to determine the impact energy by measuring the velocity of the impacting cage, known as the mass of the cage. Instead, the change in pile displacement has to be further determined based on the evaluation of the pile hammer user or manually, for example, by comparing the movement of the pile mark with a scale to be placed next to the pile. Determining the displacement in this way is laborious and. . 20 slow, and the possibility of estimation errors during measurement is high. In addition, due to this measurement, the load bearing capacity of the pile is only determined after ···. Due to this and possible miscalculations, the pile is often struck too tight. This can cause the strain on the pile to become too large at the end of the dip or the end of the pile to hit a bedrock deeper than the intended depth, with the risk of pile damage: ''; grow. To eliminate these problems and to improve the reliability of pile immersion measurement, some automated pile displacement measuring devices have recently been developed. They are in principle functional in themselves, but they are ··· complex in their field and difficult to operate because they include pile-mounted measuring sensors that must be mounted around the pile before each pile is started. In addition, the use of currently known submersible depth measurement,.,: Devices is often not possible in difficult terrain or eg when:. . piles are struck in submerged soil.

It is an object of the present invention to provide a method for overcoming the above-mentioned problems associated with methods of measuring the displacement of a submerged pile by the prior art. In particular, it is an object of the invention to provide a method for automatically and real time measuring the displacement of a pile immersed in a pile hammer and its change during pile immersion without the hassle of having to prepare separately for each pile. It is a further object of the invention to provide a device of simple construction and reliable and accurate operation for applying the above method.

The object of the invention is achieved by a method and a device characterized by what is stated in the claims.

The method according to the invention is characterized in that the distance measuring device attached to the immersion device measures the distance of the immersion device relative to the reference point 10 and that the measurement results obtained thereby determine the pile displacement. In such a method, by drilling or drilling with a pile hammer, the displacement and displacement of the pile to be submerged can be measured completely automatically, eliminating the need for scaling and laborious and cumbersome preparation. In addition, such a method enables real-time and accurate measurement to be made and without the possibility of errors in manual measurement methods. Thanks to real-time measurement results, pile immersion can always be terminated in a timely manner, avoiding the pile being pushed too deep and the resulting damage to the pile.

In a preferred embodiment of the method of the invention, the distance of the pile hammer from the reference point is measured by a non-contact distance measuring device. The non-contact distance measuring device is fast and accurate and simple in design. Therefore, it does not slow down or limit in any way: the normal operation of the pile hammer. In addition, interfaces formed by a liquid or gaseous substance, such as a water surface, can also be used as a reference for a non-contact distance measuring device.

• '; In another preferred embodiment of the method according to the invention, the distance is measured by a distance-measuring device based on wave motion. Measuring devices that work in this way are accurate, compact and reliable. In addition, they are very fast so they can be used to measure distance; · “In real time, allowing timely stopping of beats.

In a third preferred embodiment of the method according to the invention, the distance is measured after striking the pile hammer before starting to raise the blade again. In the course of pile driving, the sinking of the pile 3 115071 takes place in stages. When the measurement is made at the above point, the immersion depth measurement can be done in real time, because then the pile has just been moved by the impact and then it has to be decided whether to start a new stroke or to stop striking if the pile has already reached the planned parameters 5 (requirements). In addition, when the measurement is made immediately after the shot, the measurement processing unit will have as much time as possible to process the measurement results and make the above decision.

In a fourth preferred embodiment of the method according to the invention, the displacement is determined by subtracting the measurement results obtained after 10 strokes from the measurement before the strokes, whereby the resulting difference is the pile displacement as a function of the strokes of the pile hammer. From the results of measurements made in this way in the course of hammering, it is possible to determine parameters related to the piling process control, such as the pile displacement change and the pile displacement change rate. the completion of the pile dip 15 completion can be easily accomplished by the measurement processing unit, automatically or otherwise, e.g. based on an alarm provided by the system.

The device according to the invention is characterized in that the device comprises a distance measuring device attached to the immersion device for measuring the distance of the immersion device from the reference point. The measuring device attached to the submersible device can • accurately determine the position of the top of the pile relative to the reference point, irrespective of the position and possible movements of the pile machine and its components. This will allow accurate and real-time determination of pile displacement, allowing easier, faster and risk-less embedding of the pile into the desired depth. In addition, such a measuring device enables the measurement to be carried out completely automatically, without the slow and laborious preparation of the existing measuring equipment.

In a preferred embodiment of the device according to the invention, the distance measuring device is: a measuring sensor for measuring the distance of the reference point, which is connected to the immersion device body, and is connected to a measuring unit for measuring results located in the immersion device. With such a measuring device, the pile immersion measurement is made at appropriate intervals so that the pile immersion progress is easy to follow, and the appropriate immersion termination time can be reliably determined, thus avoiding the risk of deep immersion. In addition, 35 measurements are made in such a device at a desired time, e.g. in the case of a pile-hammer, immediately after the pile-hammer is struck. Further, a very short measuring time (e.g., a few milliseconds) is usually sufficient for a non-contacting measuring device and it is possible to transfer the electrical measurement result obtained thereon very quickly to the measurement processing unit. Thus, such a device is particularly well suited as a measuring device for a pile hammer, because it allows the measurement of the displacement of a 5-pile, even though the pile is struck continuously at maximum stroke rate.

In another preferred embodiment of the device according to the invention, the distance between the measuring device and the pile hammer is damped by a clamping element for damping vibrations transmitted to the measuring device by shocks. If the measuring device is attached directly to the body of the pile hammer, vibrations due to punches may affect the measurement results. The dampened mounting member reduces the adverse effects of vibrations, thereby improving the accuracy of distance measurement and the reliability of the displacement determination. In addition, the damped mounting member reduces the mechanical stress on the measuring device due to the impact, thereby increasing the life of the measuring device.

In a third preferred embodiment of the device according to the invention, the device comprises a measuring moment timer to determine a suitable measuring moment. In the case of a pile-hammer, the most advantageous measurement moment is immediately after the stroke, as this will leave most time before the next stroke. The timing device can reliably and easily determine the moment when measurement 20 starts, so that the measurement can be made at the time mentioned above. The timing device suitable for this purpose is, for example, an acceleration sensor which provides a voltage pulse to the measurement unit. .i: 'The hammering hammer strikes the top of the pile.

; In the following, the invention will be described in more detail with reference to the accompanying drawing, in which Figure 1 is a schematic drawing of a pile hammer fitted with a distance measuring device according to the method of the invention; measuring device.

,; The piling hammer shown in Fig. 1 is known per se in terms of structure and function; · 'A pile-hammer that can be attached to a suitable, usually with tracks; a working machine (not shown in Figure 1) with a guide boom for a piling hammer. Together, these devices form a piling machine, which can be used to dredge piles used as foundations for buildings or the like. The piling hammer according to Fig. 1 comprises a frame 1, a hump 2, an actuator 3 and a shock energy control 115071. 4. The piling hammer according to Fig. 1 also includes a distance measuring device 5 attached to the piling hammer frame 1 to measure e.g. In addition, the pile hammer of Figure 1 further comprises a measurement unit 5 and the necessary connection cables or the like between the measuring unit 5 and the measurement unit (not shown in Figure 1).

In the case of Figure 1, the distance measuring device 6 is an optical distance sensor based on a laser triangle measurement. It can measure the distance between the nearest interface in the sensor measurement direction, such as the ground and the sensor. Therefore, as shown in Fig. 1, a sensor attached to the side of the pile hammer body can measure the distance z of the pile hammer body 1 from the reference point. The reference point may be the ground surface 7 as shown in Figure 1 or a separate reference point which is as stationary as possible at a suitable point. The reference point may also be in relation to the direction of impact of the pile hammer, if-15 in a suitably selected direction y. The bearing angle is taken into account in the pile up-pile calculation by entering it into the measurement processing unit before starting pile punching. For the purpose of adjusting and measuring the bearing angle, the sensor connection in some application may include an angle measuring device which measures the bearing angle between the sensor and the striking direction, and an actuator for remotely adjusting the bearing angle 20 of the sensor. Measurement ·. : The measurement data received from the sensor during the reading is read into the measurement / processing unit located on the piling machine. In the embodiment of Figure 1, the measurement result '*'! The processing unit is a computer equipped with a measuring card suitable for reading from the sensor, and a computer program which can be used to determine the measurement results [* 25, e.g. pile hammer distance from reference point, pile displacement '' and displacement change. In this case, the apparatus further includes a timing device :: at the time of measurement. This is accomplished by importing the workload command data from the control device of the piling hammer as a unit for processing the measurement results; '.: For an existing computer. Based on the command data, a computer that is responsible for collecting measurement results can be programmed to perform a measurement, e.g., after hitting a pile hammer before starting the next stroke.

When using the pile hammer as shown in Figure 1, the pile hitting itself is:. ·. in a known manner, but the manual pile-displacement determination usually not carried out is used, but the pile-displacement machine 35 of the invention is used to determine the pile displacement. Therefore, before starting to pile on the pile, the distance measurement is started. The first measurement result 6 115071 is read into the memory of the measurement processing unit when the pile is ready for punching at the desired point with the pile's grounding end facing the ground. After that, start pounding. During pile immersion, the measurement processing unit reads the measurement from the distance sensor after each stroke (prior to the start of the next stroke) and calculates the pile up, displacement, and the corresponding impact energy and pile capacity. In this way, the pile immersion proceeds until the pile is close to the design depth or when the pile capacity is close to the design target value. At this point, the measurement processing unit will indicate the number of strokes still required to obtain 10 piles at the planned immersion depth. If the pile does not sink to the intended depth with this stroke rate, the unit handling measurement results will obtain a new estimate of the additional stroke required after the last stroke. If, on the other hand, the pile is sinking too deep, an alarm will be triggered before the last necessary stroke so that the pile can be stopped before the pile is sunk too deep. 15 In addition, if the change in pile displacement suddenly decreases rapidly, an alert will be given for the possibility of the pile striking the bedrock. After the pile has been hit, the pile depth change history, stroke rates, load capacities, etc. can be stored in the memory of the measurement processing unit for later processing and analysis.

The piling drill shown in Figure 2 is also known in its structure and function as such. It is also intended to be fastened to the machine of the previous example. : a working machine (not shown in Fig. 2), whereby the devices together form a piling machine with which the piles can be submerged by drilling. The piling drill of Fig. 2 includes vertically movable attachments to the implement. a drill machine 10 and a drill pile 11 to be attached thereto, the aperture portion of which has a bore 12 for drilling the pile into the ground. Further, the piling drill comprises a distance measuring device 13 and a measuring device according to the method according to the invention. · Results Processing Unit (not shown in Figure 2).

In the embodiment of Fig. 2, the distance measuring device 13 belonging to the piling drill is implemented with an ultrasonic transducer attached to the side of the drilling machine so that it measures the distance of the drilling machine from the ground or other suitable reference point. The measurement processing unit is, like the previous one, a computer placed in a convenient location on a piling machine, where ·, is a measuring card and a suitable computer program for processing and converting the measurement results to a suitable format. The point measured by the ultrasonic transducer is not point-like, as in the laser triangle transducer used in the previous application. Therefore, when used, the reference irregularities do not interfere with the 7115071 measurements with the sensor facing in any direction. This makes the ultrasonic transducer well suited for applications where uneven ground is used as a reference.

The apparatus according to the method of the invention may be implemented in many ways different from the exemplary embodiments set forth above. It is essential that the apparatus according to the method include a distance measuring device attached to the pile dipping device, which can measure the distance of the dipping device moving with the pile with sufficient accuracy to the reference point during automatic pile dipping. Suitable non-contact distance measuring devices and methods are currently well known. The most suitable ones are the relatively small and compact units, which are well tolerated by vibration and sudden fluctuations. In addition, at least in the piling drill as shown in Figure 2 (which does not involve shocks caused by punches and vertical movements of the immersion device associated with the device of Figure 1), distance measuring devices operated by a mechanical measuring arm 15 can also be used.

The invention is not limited to the preferred embodiments shown, but may vary within the inventive idea of the claims.

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Claims (7)

A method for measuring a distance, in particular for determining the submerged section of a pile (5) which is lowered into the soil (7) or water by a peeler's hammer (1-5 4) during the immersion, the distance gauge (6) attached to the fur hammer (1-4) of the peeler machine (6) measures the distance between the fur hammer (1-4) and a reference point (7) and from the measured result obtained by the fur hammer (5), characterized by measuring the distance between an existing reference point, such as a ground or water surface (7), separated from the pellet machine, and the pellet hammer, and the distance measured after the pellet hammer (1-4) has been struck, before starting the lifting of the pile (2). ) again. 15 Method according to Claim 1, characterized in that the distance between the pile hammer (1-4) and the reference point (7) is measured by a distance meter (6) operating in a non-contact way. Method according to Claim 1 or 2, characterized in that the distance is measured with a road movement based distance meter (6). A method according to any one of claims 1-3, characterized in that '/ the submerged section is determined by obtaining a prior commencement of>' '! the slurry obtained measurement result subtracts the slurry results obtained after the stroke, ·· **, whereby the resulting difference is the submerged section of the pile (5) as a function of the type of the hammer (1-4). Apparatus for applying the method according to claim 1, comprising a spacer hammer (1-4) fixed spacer (6) for measuring the distance between the pelvic hammer (1-4). ) and a reference point (7), and a treatment unit for measuring results for processing the measurement results obtained with the measuring device and for determining the submerged section of the pile '' '(5), characterized in that the distance meter (6) is arranged to measure the distance between the pellet hammer (1-4) and one with respect to the pellet machine; : 35 different existing reference points, such as a ground or water surface (7), and that the device comprises a measurement timer to determine a suitable timing of the measurement. 11 115071 Apparatus according to claim 5, characterized in that the distance meter (6) is a measuring sensor attached to the pile hammer (1-4) which measures the distance to the reference point (7) without contact and which is connected to a unit for processing in the pellet machine. of measurement results. 5 Device according to claim 5 or 6, characterized in that between the distance meter (6) and the pile hammer (1-4) there is a damped fastening means for damping vibrations transmitted from the blows to the distance meter (6). «» ·> * · '* ♦ * «« t · • · • I »•» • ·>