FR2858051A1 - Wall deformation measuring device for construction field, has tightness unit, and capacitive sensor to measure relative movement of target unit with respect to sensor support, where measurement is measure of deformation of wall - Google Patents

Abstract

The device has a capacitive sensor (5) and a tightness unit. A target unit is coaxial with a sensor support (6). The target unit and the support are connected to respective anchoring units (3b,3a) by corresponding spherical plain bearing rod ends (7b,7a) and hinges (14b,14a). The sensor measures a relative movement of the target unit with respect to the support, where the measurement is a measure of deformation of a wall. The target unit includes a target (8) and a bar (30) and the tightness unit has sealing gel (13), screws (21, 22a, 22b), O-rings (20, 23, 25, 28) and a wiper seal (29). Independent claims are also included for the following: (a) a method of installing wall deformation measuring device (b) a method of measuring deformation of a wall.

Description

DEVICE AND METHOD FOR DEFORMATION MEASUREMENT

  The invention relates to a deformation measuring device, as well as a deformation measurement method, 5 mainly intended for the deformation measurement of civil engineering works.

  Among the existing strain measuring devices for civil engineering works, there are vibrating wire sensor systems or vernier caliper systems. These systems make it possible to measure large deformations of the order of a few millimeters, but are not precise enough for all types of structures, in particular those for which it is desired to measure concrete aging in a very precise manner or which are subject to small deformations (ie displacements generally of the order of a few micrometers per meter).

  On the other hand, there are commercially available sensors such as capacitive, inductive, potentiometric, optical fiber or incremental type sensors, which are standard deformation or displacement measuring sensors of the market, and which are effective for measuring ranges typically of the order of several millimeters with a resolution of the order of 0.1%. Such sensors are commonly used for displacements on short lengths (so-called short bases in terms of civil engineering, typically 5 to 20 cm). In adaptation for much more accurate resolutions on long bases (which are called long bases in terms of civil engineering, typically 2 2858051 more than about 50 cm), there is the problem of the lower limit and the the resolution of these sensors that are not good enough. Thus, there is currently no deformation measuring device or deformation measuring method for efficiently measuring displacements or deformations of walls of structures of the order of a few micrometers per meter. and per year.

  In the end, the devices described in the prior art are unsatisfactory, and no industrial device exists to date.

  The device according to the invention makes it possible to overcome the problems described above, and to provide other advantages, by setting up a device 15 capable of metrological validation, and in particular capable of being implemented without constraint. mechanical or stiff, waterproof and lightweight, easy to assemble and very reliable.

  Thus, the device according to the invention is a device for measuring the deformation of at least one wall, comprising at least two anchoring means on said wall, at least one sensor, at least one sensor support means, at least one sensor sealing means and at least one target means of the sensor, said target means being connected to at least one anchoring means by at least one ball joint means, and said sensor support being connected to at least one other means of anchoring by at least one other ball joint means, said sensor being able to perform a measurement of a relative displacement of said target means with respect to said sensor support means in a cavity measurement of the sensor, said measurement being a measure of deformation of the wall.

  By wall is meant according to the invention a substantially two-dimensional space or at least a part thereof. By deformation is meant according to the invention any change in distance between at least two points of said wall. It is usually measured in Mm / m. A deformation measures a displacement (in tm for example) with respect to a reference length that is a measurement basis (for example about 1 μm).

  According to the invention, and according to the general acceptance of the civil engineering, a deformation is expressed in Mm, and the measurement base is expressed in m. If displacement is reported on a basis of 1m, a strain of gm / m is obtained.

  According to the invention, the space between the two anchoring points on the wall is not necessarily plane or substantially two-dimensional. It can also be three-dimensional.

  In general and preferably, two anchoring means and two ball joint means are present.

  According to the invention, said wall is advantageously an element of a civil engineering work or such a civil engineering work. By civil engineering means according to 25 the invention any structure such as bridge, tunnel, historical monument, building, beam, rock and soil.

  Preferably, said wall is made of concrete.

  The device according to the invention is particularly advantageous in that it makes it possible to have a system that can be validated in metrology, which is a first in the field of long bases in civil engineering. In addition, the device according to the invention is generally very easily assembled, and designed for a service life of at least twenty years almost without maintenance. Finally, the device according to the invention makes it possible to insert any type of deformation sensor technology.

  In addition, the presence of a sealing means, which may be in practice in part as a watertight shell, is largely around the sensor, allowing it to not be influenced by external conditions such as humidity. , wind, rain ...

  Of course, the external temperature is an external condition generally experienced by said sensor, and this is why, in a particularly advantageous manner according to the invention, the device is associated with at least one means for measuring the temperature outside the sensor, as it will be explained later. This may make it possible to measure as efficiently as possible taking into account the parameter that is the temperature outside the sensor.

  The device according to the invention is particularly advantageously very easy to assemble, set up and follow. In addition, it is remarkably light.

  The device according to the invention is still such that, advantageously, virtually any deformation is transmitted back to the sensor, virtually without mechanical stress or stiffness, which would reduce the deformation measurement efficiency.

  According to a preferred embodiment of the invention, said target means comprises a bar and a target coaxial with said bar. In a particularly preferred manner, said bar is fixed by screwing and bonding to said target substantially on the same axis so that they form substantially a mechanically secured assembly. It is also possible according to the invention that these two parts which are a substantially coaxial bar and target form a single mechanical part.

  In a particularly preferred embodiment according to the invention, said bar, said target and said sensor support means are substantially coaxial. This advantageously allows a very good measurement accuracy. The device according to the invention advantageously comprises any coaxial means for setting said bar, said target and said sensor support means.

  According to the invention the device further comprises at least one guiding means, preferably self-lubricating such as a ring, a ball bearing, a needle bearing, or a bearing. Preferably such a guide means is a ring, preferably self-lubricating, for example mounted in a sleeve. Said guide means 25 advantageously makes it possible, while keeping the coaxiality previously indicated, to promote sliding and thus to implement the displacement measurement according to the invention in the most efficient manner possible.

  The self-lubrication, preferred according to the invention, such a guiding means, ensures as long as possible the life of the device once installed.

  According to the invention, advantageously and particularly preferably, the device is generally capable of measuring a deformation of 1 to 100, preferably of 5 to 30, even more preferably of 5 to 15 micrometers per meter, and this usually for a period of about one year. The deformation is most often measured with respect to a wall dimension and is generally a few micrometers per meter, and this generally for a period of about one year.

  In a preferred embodiment of the invention, said sensor sealing means is such that said measuring cavity of the sensor comprises at least one neutral gas. Indeed, the presence of said sealing means already makes it possible to protect the sensor from dust and from various external parameters which could disturb the measurement. By the additional presence of a neutral gas according to said embodiment, for example of nitrogen type at 3% humidity, it is possible to confine the sensor and therefore the sensor measurements in a protected atmosphere. Advantageously, such confinement can be achieved already at the mounting of the device, particularly in the factory, and / or it can also be put in place at the level of the use of said device in measurement. More generally, said cavity generally comprises air or any other gas or gas mixture chosen by those skilled in the art.

  According to the invention, the sensor is preferably chosen from inductive type sensors, capacitive type sensors, potentiometric type sensors, optical fiber type sensors and incremental type sensors. As is known to those skilled in the art, certain types of sensors require greater sealing precautions than other sensors which are respected by those skilled in the art for the development and assembly of the sensor. device according to the invention.

  Thus, for a capacitive type sensor, it is generally more important to protect said sensor and to plunge it into a neutral atmosphere according to the previous embodiment.

  The device according to the invention is generally such that only the influence of the outside temperature as a parameter outside said device influences the measurement of deformation performed by said sensor.

  In one embodiment of the invention, the device according to the invention further comprises at least one means for positioning the target means with respect to the two ball joint means, which can be used during the installation. said device on the wall, and which participates in the connection of the target means by means of ball joint. Advantageously, said positioning means comprises at least one threaded rod, adapted to be fixed by screwing on at least one connecting means 25 ball and at least one lantern (or lantern adjustment), adapted to move by screwing on the means of target, said threaded rod and said lantern being fixed by screwing with respect to each other and being substantially coaxial. It is also possible according to the invention that these two parts which are a substantially coaxial threaded rod and lantern form a single mechanical part.

  In this case, of course, said ball joint means and said target means then each have a complementary thread for screwing respectively said threaded rod and said lantern. Thus, the positioning is generally able to be achieved by displacement by screwing the lantern relative to the target means. Said threaded rod and said lantern are generally each in Invar.

  In such an embodiment, the device can be put in place and the anchoring means fixed to the wall without this modifying the use of the device in measurement, because the device can generally be anchored advantageously with a tolerance. running distance between the fastening means of + about 1 cm, on a measurement basis, defined as the distance between the anchoring points of the anchoring means, of 1 m, as will be explained hereinafter in the description of the figures.

  Preferably each of the sensor support means and target means is at least partly, preferably substantially totally, invar. More generally, Invar is used according to the invention for the parts of the device according to the invention which participate in the fluctuation of the measurement when the device is subjected to an expansion resulting from a temperature variation. In general, Invar parts have undergone after machining a surface treatment, for example of the white zinc coating type, against corrosion. Such a material 2858051 is a metallic material advantageously having a low coefficient of thermal expansion.

  Advantageously, the other parts of the device according to the invention are made of stainless steel or stainless steel. Those skilled in the art can also use any other material having the characteristics of Invar, such as a material selected from the group consisting of composites and alloys with negative or compensated expansion. By composite is meant according to the invention a generally non-metallic material such as a material selected from the group consisting of fibers, resins or the like. By alloy is meant according to the invention a generally metallic material.

  In an advantageous embodiment according to the invention, the device is such that it is associated with at least one means for viewing and / or acquiring and / or storing data of the sensor. Said means for viewing and / or acquiring and / or storing data of the sensor may advantageously be associated with at least one means for measuring the temperature outside the sensor, which makes it possible to measure as efficiently as possible taking into account the parameter that is the temperature outside the sensor. By temperature outside the sensor is meant according to the invention the temperature around the device of the invention in which the sensor is present, that is to say the external atmosphere in which the device according to the invention is present.

  By means of visualization and / or acquisition and / or storage of data is meant according to the invention any means, for example of the computer type, allowing 2858051 to acquire at least one, preferably a plurality of (c ie at least 10), measures as data, and / or display and / or store them over time. By visualization is meant according to the invention a display of at least one value expressed in units of length or any other unit used by the sensor such as for example the voltage, the intensity, or the frequency.

  Advantageously, the device according to the invention comprises at least one locking means of said device once installed. Such a means advantageously avoids undesired displacement of a part of the device relative to the other parts during the service life of said device, without adding unnecessary mechanical stiffness.

  The invention also relates to a method for installing at least one device according to the invention comprising the following steps: at least one anchoring of two anchoring means of said device, at a distance from each other which 20 constitutes a base of the measurement, and * at least one ball-joint placement of at least one assembly, pre-assembled or not, of a sensor, a sensor support means, a means for Sealing the sensor and a sensor target means, in connection with said anchoring means. Particularly advantageously according to the invention, said measuring base is from about 50 cm to about 2 meters long. Typically, said measurement base is for example approximately 1 meter long.

  Preferably, said method is followed by at least one, preferably and advantageously one, adjustment step of said sensor within said device.

  Preferably, such an adjustment is made so that one end of the target means is positioned in the measuring cavity of the sensor. For example, such an adjustment is such that said end is substantially in the middle of said measuring cavity, as is known to those skilled in the art. Those skilled in the art must adapt such an adjustment according to what is sought with respect to the use made of the device according to the invention, able to deform.

  Advantageously, such an installation method is extremely simple since, all of the device being advantageously assembled in the factory, with the exception of the ball joint means and the anchoring means, it suffices to carry out a fixation. anchoring rods on a wall for example concrete to install said device. The ease of installation is very advantageous and the saving of time is notable. It is recalled here that the wall between the two anchor points thus defined is not necessarily flat according to the invention.

  Advantageously, the anchoring means are placed as far as possible from any source of disturbance of the measurement. Such a source of disturbance of the measurement may for example be a heterogeneity of the wall or, in the case of use in measurement of the device placed on a structure or a building, an entrance or exit of said structure or said building, etc. 12 2858051 It is also possible to install at least two devices according to the invention.

  The device according to the invention can be installed both in a substantially horizontal plane and in a substantially vertical plane or in an inclined plane in an intermediate position between a horizontal plane and a vertical plane, on one side or the other side. such a plan, for example on a floor or under a ceiling.

  Advantageously, the device according to the invention 10 can also serve to monitor the holding of the anchor.

  The invention also relates to a deformation measuring method comprising at least one installation according to the preceding method of at least one device according to the invention and at least one measurement step by means of said device.

  The invention also relates to a deformation measuring method comprising the following steps: at least one anchoring of two anchoring means, at a distance from one another which constitutes a measurement base, at least one placing, by ball joint connection, at least one assembly, pre-assembled or not, of a sensor, a sensor support means, a sensor sealing means and a sensor target means, on said ball joint anchoring means, said target means being bonded to at least one anchoring means by at least one ball joint means, and said sensor support means being bonded to at least one other means of anchoring by at least one other ball joint means, said sensor being adapted to measure a relative displacement of said target means with respect to said sensor support means in a measuring cavity of the sensor, and at least one measurement of displacement of said sensor with respect to said base, said measurement being a measure of deformation of said wall.

  In a particularly advantageous manner according to the invention, said measuring base is from about 50 cm to about 2 meters long. Typically, said measurement base is, for example, approximately 1 meter long.

  Preferably, between the placing step and the measuring step, said method comprises at least one, preferably and advantageously only one, adjustment step of said sensor within said assembly, substantially similar to that which has has been explained in the method of installation of the device of the invention described above.

  According to a preferred embodiment of the invention, said method further comprises at least one external manual measurement step, and therefore easily accessible, for example using a depth gauge. Such a step advantageously allows an external verification during assembly and / or during the installation of the device on the wall.

  A depth gauge is a common measurement tool used by those skilled in the art. Those skilled in the art can advantageously dispose and use the depth gauge during assembly, for example in the factory, for the installation of the device and if necessary during the life of said device. In this case, the device is such that, on the face of at least one of the component elements, for example the face of a cover member, one or more registration marks, preferably two registration marks placed at 180 from each other are indicated. In this preferred case, the presence of the two marking lines placed at 180 from one another makes it possible to overcome the absence of visual contact with one of the two lines during placement along the wall. Such a registration advantageously makes it possible to ensure that the manual measurement thus produced is performed always in the same place for better repeatability.

  The invention will be better understood and other features and advantages will appear on reading the description which follows, given in a non-limiting manner, with reference to FIGS. 1 to 4.

  Figure 1 schematically shows a sectional view of a device according to the invention.

  Figure 2 schematically shows a sectional view of another device according to the invention.

  FIG. 3 schematically represents a part of the device according to the invention of FIG.

  Figure 4 schematically shows the device according to the invention of Figure 1 set up 25 on a wall.

  Figure 1 schematically shows a sectional view of a device 1 according to the invention. The device 1 comprises two means 3a and 3b anchoring on a wall 4 (shown in Figure 4). Said anchoring means 3a and 3b are, in the device 1 shown in FIG. 1, each a threaded location respectively 3a and 3b for inserting a threaded rod (not shown) respectively into a ball end 7a and 7b. The device 1 comprises two connecting means 5 ball, 7a and 14a, and 7b and 14b, or a ball joint means by anchoring means. A ball joint means comprises the parts 7a and 14a, the part 7a being a ball end, and the part 14a being the (part) ball joint itself. Another ball joint means comprises the parts 7b and 14b, the part 7b is a ball end, and the part 14b is the (part) ball itself.

  The ball joint means (7a, 14a) is substantially along the axis YY 'substantially perpendicular to an axis XX' which is a coaxial axis of the device 1 15 according to the invention. The ball joint means (7b, 14b) is substantially along the axis ZZ 'substantially perpendicular to the axis XX'. The distance between ZZ 'and YY' represents a spacing (i.e. a distance between the axes that is to say substantially distance between the anchor points) or measurement base B (see Figure 4). In practice, in the trade, the parts 7a and 14a are sold in a mechanically secured assembly. Similarly for parts 7b and 14b.

  The device 1 comprises a sensor 5 of the capacitive type and a means 6 of support or support 6 of the sensor 5. The sealing means of the sensor 5 comprises a sealing gel 13 present in a cavity 31, an O-ring 20, a screw 21, two screws 22a and 22b, an O-ring 23, an O-ring 25, an O-ring 28, and a wiper seal 29. The target means of the sensor 2888051 comprises the parts 30 and 8, the workpiece (or target) 30 being shown partially in section and uncut, and a bar (or pulling) 8. It is readily seen in Figure 1 that parts 8 and 30 could alternatively constitute a single piece machined.

  The sensor 5 is associated with a cavity 33 for measuring the sensor. As will be explained below, the sensor 5 is able to make a measurement of a relative displacement of the target means consisting of the parts 8 and 30, and in this case the displacement of the part 30, relative to to the support 6 of the sensor 5. Said measurement is a measure of deformation of the wall 4, as previously explained.

  The main parts of the device 1 are the support 6 of the sensor 5, a sleeve 9, a cover 10, the target 30 and the bar 8. We will explain below the assembly of all these parts in connection with the other parts of the device. Device 1. It is readily seen in Figure 1 that the part 6 could alternatively be made two different pieces.

  The sensor 5 is here a capacitive sensor. The sensor 5 is inserted into the support 6 by the side of the cavity 31. After insertion, a wire 11 connects the sensor to a conditioner 12, as shown in FIG. 4. A conditioner is an element electrically connected to the sensor, which ensures the excitation and the restitution of a signal proportional to the measurement of the displacement of the target. It can also provide visualization of the sensed information in different signal forms as previously explained. According to the invention, we have considered that the conditioner 12 is an element of the visualization and / or storage and / or data acquisition means. Generally, in the trade, the sensor is delivered with its conditioner. FIG. 4 shows that an electrical wire 40 connects the conditioner 12 to a power supply box 38, powered by the power grid and generally delivering a low voltage (12 V or 24 V). FIG. 4 also shows that an electrical wire 37 connects the conditioner 12 to a viewing and / or storage and / or data acquisition box 39, generally in the form of a computer system of PC type equipped or not an acquisition card. The housing 39 forms with the conditioner 12 the display means and / or acquisition and / or data storage, according to the invention.

  It is then proceeded to the establishment, on the support 6, the seal 20, then the sleeve 9 is centered and screwed on the support 6. A screw 21 keeps the attachment. It is also possible and not shown in FIG. 1 to insert a screw next to the screw 21 which presses the sensor 5 so as to be sure that the sensor 5 will be mechanically locked on the support 6, and to ensure electrical continuity between the sensor 5 and the support 6. The coaxiality is adjusted by guiding between the target means consisting of the parts 30 and 8 and the support 6 of the sensor 5 during assembly.

  The insertion of the target 30 is then carried out by simply pushing it into the heart of the sleeve 9. Advantageously, two screws 22a and 22b are mounted only after the part 30 has been inserted into the sleeve 9, which allows 18 2858051 to keep the measuring cavity 33 at atmospheric pressure.

  The location of the screws 22a and 22b can also allow to introduce a neutral gas as previously indicated. After placing the piece 30 in the sleeve 9, the two screws 22a and 22b are inserted. Before placing the piece 30 in the sleeve 9, it is noted the presence of a seal 23 and a ring 24 guiding glycol, which is advantageously a self-lubricating guide means according to the invention. The advantage of the presence of such a ring with respect to a ball or needle bearing is the relatively small size of such a ring 24. Said ring 24 advantageously allows a relative displacement of the target medium (8,30) relative to the means 6 for supporting the sensor 5 as easily as possible.

  The bar 8 is inserted by screwing and gluing into the piece 30. An elastic ring 27 is installed in the groove of the target 30. Finally, the cover 10 is inserted and centered on the sleeve 9, with an intermediate ring 25 , all held by three screws 26a, 26b and 26c (the screws 26b and 26c are not shown). Such a ring 27 advantageously limits the movement of the bar 8 in a direction opposite to the sensor 5. The presence of additional seals, namely an O-ring 28 and a wiper seal 29, makes it possible to finish sealing the device 1.

  The coaxiality axis of the device 1 is the axis X'X, the target 30, the bar 8 and the support 6.

  In the part of the device 1 opposite to the sensor 30 5, a piece 18 of lantern type is inserted by screwing on the bar 8 8 and is able to be screwed during the installation of the device 1. Within the lantern 18 is has a threaded rod 19 which is adapted to be inserted into the means (7b, 14b) of ball joint. It can easily be seen in FIG. 1 that parts 18 and 19 could alternatively constitute one and the same machined part.

  A nut 17 advantageously allows once the installation set up to avoid a subsequent movement of the piece 18 relative to the bar 8. Such a nut 17 is known to those skilled in the art for its role of blocking means and is usually called a lock nut.

  In the device 1, the part 6 is advantageously mounted inside the ball portion 14a of the ball joint means (7a, 14a), the presence of two flats (allowing the passage of a key) participates in fixing . The fixing then takes place by means of the nut 15a and the counter-nut 16a, the presence of the nut 15a making it possible to improve the amplitude 20 of the ball-and-socket motion with respect to the presence alone of a conventional nut. . The machining of the nut 15a makes it possible not to use a washer to achieve this same functionality. This advantageously facilitates mounting on the wall 4 by reducing the number of parts to be handled.

  At the other end, the rod 19 is inserted in the same way inside the ball portion 14b of the ball joint means (7b, 14b), and the nut 15b and the counter-nut 16b serve to lock said rod 19 The nuts 16a and 16b serve as counter-nuts, that is to say allow the final locking of the device 1 once it is installed. The machining of the nut 15b makes it possible not to use a washer to achieve this same functionality. This facilitates mounting on the wall 4 by reducing the number of parts to handle.

  When installing the device 1 according to the invention on a wall 4, two threaded rods serving as anchors (not shown and external to the device 1 as defined herein, but which can also be part of said device 1) are firstly fixed at a distance corresponding to a measurement base B on the wall 4.

  Then the ball joint means (7a, 14a) and (7b, 14b) are inserted on said pins, then the assembly consisting of the rest of the parts of the device 1 is inserted into said means (7a, 14a) and (7b). , 14b) ball joint, with possible adjustment by the displacement of the lantern 18 relative to the bar 8 and tightening by the nuts and locknuts 15a and 16a, and 15b and 16b, and 17.

  In the device 1 as shown in FIG. 1, it can be seen that, with respect to the stroke C (here fixed) of the lantern 18 with respect to the rod 81e, device 1 is installed with an abscissa x1 on this run C. Advantageously, the device 1 may comprise a ball spring threaded pusher (not shown) which makes it possible to be sure of a good electrical contact between the target 30 and the cover 10. In fact, for a measurement with the With the assistance of the capacitive type sensor 5, the target 8 must be set to potential and one must be sure of the electrical connections.

  Advantageously, the device according to the invention comprises at least one locking means of said device once installed. In the case of Figure 1, the device 1 comprises as locking means the nuts 16a and 16b and the nut 17, these nuts can also be called lock nuts in a manner known to those skilled in the art.

  Figure 2 schematically shows a sectional view of another device 1 'according to the invention. The device 1 'according to the invention has great similarities with the device 1 of FIG. 1, with the difference that, with respect to the stroke C of the part 18 with respect to the part 8, the displacement is of a x2 abscissa and the sensor is of the inductive type 5 ', which leads to modifications and additions with respect to the device 1. The x2 abscissa represents a near maximum distance in the race C or an almost minimal distance from the B. A measurement cavity of the sensor 5 'is represented by the recesses 33' and 34. The support 6 'of the sensor 5' is slightly different with respect to the support 6 of the device 1. A gel of sealing 13 'is present in a cavity 31'. Since the sensor 5 'is of the inductive type, the presence of a rod 35 which forms part of the plunger core (not shown) of the sensor 5' is noted. The rod 35 is screwed into the target 30 '. A nut 32a ensures the attachment between the target 30 'and the rod 35. The end of the rod 35, by its threading, allows the centering of the plunger (not shown) in the body of the sensor 5', depending on the manufacturer's recommendation of said sensor 5 '. A slot 36 is a recess for the threaded rod 35. A lock nut 32b prevents subsequent movement of the rod 35 relative to the target 30 '. The target means according to the invention is represented by the parts 30 'called the target and the bar 8.

  FIG. 3 schematically represents a part of the device 1 according to the invention of FIG.

  With respect to the stroke C, we see that the abscissa is x3 = 0, which is a maximum distance from the center distance or measurement base B of the device 1.

  Figure 4 schematically shows the device 1 according to the invention of Figure 1 set up on a wall. FIG. 4 thus shows a wall 4 on which a device 1 according to the invention of FIG. 1 is installed. As explained above, the electrical wires 11, 40 and 37 make it possible to connect, to the sensor 5, the housing supply 38, storage and / or data acquisition 39, and conditioner 12.

  The base B is seen as it is during the installation of the device 1. This device 1 is able to measure the deformations of the wall 4 over time, typically over a period of 20 years.

Examples

  The following examples serve to illustrate the invention without limiting the scope.

  The device 1 according to the invention as shown in Figure 1 and the device 1 'according to the invention as shown in Figure 2 were manufactured. The center distance or measurement base B between ZZ 'and YY' 23 2858051 is lm (1 cm). The largest diameter of the lid is 50 mm.

  The parts 18, 19, 8, 30 and 6 of the device 1 are in galvanized Invar.

  The parts 18, 19, 8, 30 'and 6' of the device 1 'are in galvanized Invar.

  The other metal parts of the devices 1 and 1 'are made of stainless steel, which advantageously allows protection against corrosion. The various seals 10 (rings and scrapers, and the elastic ring 27 (also called circlips), devices 1 and 1 ', are common commercial products.

  The only pieces glued together in the embodiment of the device 1 are the parts 8 and 30, the parts 5 and 6, and the parts 6 and 11 via the gel 13.

  The only parts glued together in the embodiment of the device 1 'are the parts 8 and 30', the parts 5 'and 6', and the parts 6 'and 11' via the gel 13 '.

  The ball joints, fixing screws, the spring loaded push rod 20 and optionally the ball, as well as the glycodide guide ring, the adhesive and the sealing gel, devices 1 and 1 ', are commercially available products, known from the art. skilled person.

  The capacitive sensor 5 is here a sensor of the AOIP company of the CC5-Hta type, associated with a conditioner 12 of the AOIP company of the MCI-100 Aad type. The inductive sensor 5 'is of the SX 12 K 006 M type of the SENSOREX company, associated with a conditioner 12 of the SENSOREX company of the SX6511 type, in digital output and display 30 (which advantageously makes it possible to have a direct reading 24 2858051 the measurement made by the sensor on said conditioner), or SX3120 type at the analog output.

  The devices 1 and 1 'according to the invention thus exemplified are advantageously of a light weight.

  Additional protection is possible by the deposition at least in part of a peelable elastic film covering at least partially, preferably almost completely, the device 1 or the device 10 1 ', after its implementation on the wall. It is a classic commercial product, for example based on bitumen, tar or plastic, sold in the form of a bomb

for example.

2858051

Claims (23)

1. Device (1, 1 ') for measuring deformation of at least one wall (4), comprising at least two means 5 (3a, 3b) for anchoring on said wall (4), at least one sensor ( 5,5 '), at least one sensor support means (6,6') (5,5 '), at least one means (13,20,21,22a, 22b, 23,25,28,29; 13 ', 20,21,22a, 22b, 23,25,28,2 9) of the sensor (5,5') and at least one means (8,30; 8,30 ') of the target of sensor (5,5 '), said target means (8,30; 8,30') being connected to at least one anchoring means (3b) by at least one ball joint means (7b, 14b), and said sensor support means (6,6 ') being connected to at least one other anchoring means (3a) by at least one other ball joint means (7a, 14a), said sensor (5,5 ') being able to make a measurement of a relative displacement of said target means (8, 30; 8,30') with respect to said sensor support means (6,6 ') (5,5') ), in a measuring cavity (33, 33 ', 34) of the sensor (5, 5'), said measurement being a measure of Ormation of the wall (4). 2. Device (1,1 ') according to the preceding claim such that said wall (4) is an element of a civil engineering work. 3. Device (1,1 ') according to one of the preceding claims such that said wall (4) is concrete. 4. Device (1,1 ') according to one of the preceding claims, wherein said target means (8, 30; 8,30') comprises a bar (8) and a coaxial target (30) (X'X). 30 with respect to said bar (8). CLAIMS   1. Device (1, 1 ') for measuring the deformation of at least one wall (4), comprising at least two means 5 (3a, 3b) for anchoring on said wall (4), at least one sensor (5) 5 '), at least one sensor support means (6,6') (5,5 '), at least one means (13,20,21,22a, 22b, 23,25,28,29; ', 20,21,22a, 22b, 23,25,28,2 9) sensor seal (5,5') and at least one sensor target means (8,30; 8,30 ') (5,5 '), said target means (8,30; 8,30') being bonded to at least one anchoring means (3b) by at least one ball joint means (7b, 14b), and said means (6,6 ') of the sensor support (5,5') being connected to at least one other anchoring means (3a) by at least one other ball joint means (7a, 14a), said sensor ( 5,5 ') being able to perform a measurement of a relative displacement of said target means (8, 30; 8,30') with respect to said sensor support means (6,6 ') (5,5') in a measuring cavity (33, 33 ', 34) of the sensor (5, 5'), said measurement being a measure of deformation of the wall (4).   2. Device (1,1 ') according to the preceding claim such that said wall (4) is an element of a civil engineering work.   3. Device (1,1 ') according to one of the preceding claims such that said wall (4) is concrete.   4. Device (1,1 ') according to one of the preceding claims, wherein said target means (8, 30; 8,30') comprises a bar (8) and a coaxial target (30) (X'X). 30 with respect to said bar (8). ? 27   5. Device (1,1 ') according to the preceding claim such that said bar (8), said target (30) and said means (6,6') of sensor support (5,5 ') are substantially coaxial (X 'X).   6. Device (1,1 ') according to one of the preceding claims further comprising at least one means (24,9) for guiding.   7. Device (1,1 ') according to the preceding claim such that said means (24,9) for guiding is a ring (24) self-lubricating mounted in a sleeve (9).   8. Device (1,1 ') according to one of the preceding claims such that the sensor (5,5'), the means (6, 6 ') of the sensor support (5,5') and the means (8 ') , 30, 8,30 ') of the sensor target (5,5') are such that said sensor (5,5 ') is able to measure a deformation of 1 to 100, preferably 5 to 30, so still more preferred from 5 to 15, gm / m.   9. Device (1,1 ') according to one of the preceding claims, such that said means (13,20,21,22a, 22b, 23,25,28,29; 13', 20,21,22a, 22b, 23,25,28,2 9) of the sensor (5,5 ') is such that said measuring cavity (33; 33', 34) of the sensor (5,5 ') comprises at least one neutral gas .   10. Device (1,1 ') according to one of the preceding claims such that said sensor (5,5') is at least one sensor selected from the sensors (5 ') of the inductive type, the sensors (5) of the type Capacitive, potentiometric type sensors, optical fiber type sensors and incremental type sensors.   11. Device (1,1 ') according to one of the preceding claims further comprising at least one means (18,19) for positioning the means (8,30; 8,30') of target relative to the two means ( 7a, 14a, 7b, 14b).   12. Device (1,1 ') according to the preceding claim such that said positioning means (18,19) 5 comprises at least one rod (19) threaded, adapted to be fixed by screwing on at least one means (7b, 14b). ) ball joint and at least one lantern (18), able to move by screwing on the means (8, 30; 8,30 ') of target, said rod (19) threaded and said lantern (18) being fixed by 10 screwing relative to each other and being substantially coaxial (X'X).   13. Device (1,1 ') according to the preceding claim such that said rod (19) threaded and said lantern (18) are each in Invar.   14. Device (1,1 ') according to one of the preceding claims, such that at least each of the means (6,6') of support of the sensor (5,5 '), and means (8, 30; 8,30 ') are in Invar.   15. Device (1,1 ') according to one of the preceding claims, associated with at least one means (12,39) for viewing and / or acquiring and / or storing data of the sensor (5,5'). ).   16. Device (1,1 ') according to the preceding claim further comprising at least one means 25 for measuring the temperature outside the sensor, associated with said means (12, 39) for visualization and / or acquisition and / or sensor data storage (5.5 ').   17. Device (1,1 ') according to one of the preceding claims further comprising at least one locking means (16a, 16b, 17,32b).   18. A method of installing at least one device (1,1 ') according to one of the preceding claims comprising the following steps: * at least one anchoring of two means (3a, 3b) of anchoring 5 of said device ( 1,1 '), at a distance from each other which constitutes a base (B) of the measurement, and * at least one ball-joint placement (7a, 14a, 7b, 14b) of at least one together, pre-assembled or not, a sensor (5,5 '), means (6,6') for supporting the sensor (5,5 '), means (13,20,21 , 22a, 22b, 23,25,28,29; 13 ', 20,21,22a, 22b, 23,25,28,29) of the sensor (5,5') and a means (8 , 30; 8,30 ') of the sensor target (5,5'), in connection with said anchoring means (7a, 7b).   19. Installation method according to the preceding claim such that said measurement base (B) is from about 50 cm to about 2 m long.   20. Deformation measuring method comprising at least one installation according to the method according to one of claims 18 or 19 of at least one device (1,1 ') according to one of claims 1 to 17 and at least one measurement step by means of said device (1,1 ').   21. A deformation measuring method comprising the following steps: at least one anchoring of two anchoring means (7a, 7b) at a distance one from the other which constitutes a base (B) of measurement, at least one placement, by ball joint, of at least one assembly, pre-assembled or not, of a sensor (5,5 '), a means (6,6') for supporting the sensor (5 , 5 '), sealing means (13,20,21,22a, 22b, 23,25,28,29; 13', 20,21,22a, 22b, 23,25, 28,29) of the sensor (5,5 ') and a sensor target means (8,30; 8,30') (5,5 '), said target means (8,30; 8,30') being bound at least one anchoring means (3b) by at least one ball joint means (7b, 14b), and said sensor support means (6,6 ') (5,5') being connected to at least one other means (3a) for anchoring by at least one other means (7a, 14a) of ball joint connection, said sensor (5,5 ') being able to perform a measurement of a relative displacement of said means (8,30; 8,30 ') of 10 target relative to said sensor support means (6,6') (5,5 ') in a measuring cavity (33; 33', 34) of the sensor (5,5 '), and * at least one displacement measurement of said sensor (5,5') with respect to said base (B), said measurement being a measure of deformation of said wall (4).   22. Method of measuring deformation according to the preceding claim such that said measurement base (B) is from about 50 cm to about 2 m long.   23. A deformation measuring method according to one of claims 21 or 22 further comprising at least one external manual measurement step.