MEASURING THE CONSISTENCY OF FRESH CONCRETE

Description

[0001] The invention relates to testing the consistency of fresh concrete delivered to a construction site and to countermeasures in the event that this consistency proves to be unsuitable for the intended use. Reference to related applications

[0002] This application claims priority from German patent application No. 10 2019 108 780.5, filed on April 3, 2019, which is incorporated in its entirety by reference into this document. State of the art

[0003] Fresh concrete is usually not produced on construction sites themselves, but purchased from external suppliers. One of the most important parameters specified here is the flowability of the concrete. A delivery of fresh concrete arriving at the construction site is usually tested using the standardized flow test to determine whether its flowability meets the specification. A test area is covered with a specified amount of fresh concrete and subjected to vibration according to a specified time schedule. The diameter of the resulting concrete structure on the test area is measured twice, crosswise, and based on the average of both measurements, the fresh concrete is classified into one of six so-called flow classes (F1-F6). These flow classes correspond to consistency ranges ranging from "stiff" to "very flowable."

[0004] (Hyun-Ki Kim et al., "Flow Test: Particle-Level and Macroscale Analyses", ACI Materials Journal May-June 2017, Title 104-M36, 323-327) discloses a method for the flow test of concrete in which fresh concrete is applied to a test surface, the test surface is shaken, and then the consistency of the fresh concrete is evaluated from images of the test surface.

[0005] DE 100 07 612 A1 discloses a table for the spreading test, which records the spreading of the fresh concrete with sensors.

[0006] CN 206 930 553 U discloses an automated testing device for performing the spreading test on fresh concrete.

[0007] WO 2008 / 111 724 A1 discloses a system for the automated evaluation of the spreading test for fresh concrete by optical observation of the flowing fresh concrete.

[0008] KR 2016 0008 891 A1 discloses another test device for carrying out the propagation test.

[0009] JP 6 434 249 B2 discloses another automated device that initiates the spreading of fresh concrete on a test slab and subsequently evaluates it by optical observation. Task and solution

[0010] It is an object of the present invention to improve the measurement accuracy when measuring the consistency of fresh concrete and, at the same time, to make the measurement more reproducible. Another object of the present invention is to provide measures in the event that the consistency of a delivery of fresh concrete deviates from the specification for the intended use.

[0011] These objects are achieved according to the invention by a method for determining the consistency of fresh concrete according to main claim 1, by a method for controlling the flowability and / or the use of fresh concrete according to auxiliary claim 5, and by a device for determining the consistency of fresh concrete according to main claim 7. Further advantageous embodiments emerge from the dependent claims which refer back thereto. Disclosure of the invention

[0012] Within the scope of the invention, a method for determining the consistency of fresh concrete was developed. In this method, a predetermined amount of fresh concrete is applied to a test surface. This test surface can be, for example, a standardized spreading table. The predetermined amount can be applied, for example, using a truncated cone mold standardized for the spreading test.

[0013] The test surface is subjected to vibration according to a predefined time schedule. This time schedule may, for example, correspond to that of the standardized dispersion test.

[0014] The coverage of the test area with fresh concrete is then recorded from at least one image of the test area and / or by at least one sensor connected to the test area. The coverage is then evaluated as a parameter for the consistency of the fresh concrete.

[0015] It was recognized that this method could provide a significantly more accurate assessment of the consistency of the fresh concrete than simply measuring and averaging two diameters. This type of measurement had been optimized at the time to allow it to be performed on construction sites using the simplest tools, even without a calculator.

[0016] The more precise determination of the parameter for the consistency of the fresh concrete that can now be achieved through the use of technology also increases the meaningfulness of the comparison between this parameter and a specified target value. In the event of deviations, the extent of these deviations can be usefully quantified so that appropriate countermeasures can be taken. For example, if the deviations are not too large, it may be possible to subsequently treat the fresh concrete in order to bring its consistency parameter closer to the target value. This can be done fully automatically, for example, by prompting an operator to add a certain amount of a plasticizer or other additive to the fresh concrete. However, a corresponding control signal can also be generated, and a dosing device or other device for adding the additive can be controlled with this control signal.

[0017] In a further advantageous embodiment, the temporal progression of the coverage of the test surface with fresh concrete is recorded during and / or after the vibration from multiple images of the test surface and / or from a chronological sequence of measured values ​​from at least one sensor. This additional recording of the temporal progression, which is not provided for in the current standard for the expansion test, further increases the significance. For example, a coverage of the test surface that progresses in jumps indicates different physical processes in the fresh concrete than a coverage that progresses continuously during the same vibration of the test surface.

[0018] To vibrate the test surface, at least one electromechanical, electromagnetic, pneumatic, and / or hydraulic actuator is controlled. This also increases accuracy and reproducibility. The previous standard for the expansion test stipulates that the test surface is manually lifted using a handle until it reaches a stop and then dropped. The vibration with which the test surface falls to the stop when lifted cannot be determined and is not reproducible. Furthermore, the handle is not always released at the same speed, so the vibration with which the test surface falls back is also subject to uncertainty. Finally, the temporal sequence is also more reproducible when the vibration is driven by actuators. The previous standard for the expansion test stipulated quite large temporal tolerances for the timing of the vibrations.

[0019] In a further advantageous embodiment, the coverage of the test surface with fresh concrete is recorded using one or more pressure sensors, one or more optical sensors, and / or one or more capacitive sensors. In particular, this allows spatially resolved detection of any non-isotropic spread of the fresh concrete across the test surface, starting from the center of the test surface, when the test surface is shaken. Such anisotropic spread may indicate an irregularity in the production of the fresh concrete.

[0020] The pixels in the image of the test area are classified according to whether they belong to the free test area or to the fresh concrete on top of it. This allows the proportion of the test area covered by fresh concrete to be determined. This proportion, expressed as a percentage, can be used as an indicator of the consistency of the fresh concrete.

[0021] In combination with this, for example, a parameterized approach for the shape of the fresh concrete on the test surface can be adapted to the image of the test surface in such a way that inconsistencies with this image are minimized. In this way, the influence of imaging errors can be reduced.

[0022] In a further advantageous embodiment, the image of the test surface is transformed into a perspective view of the test surface. From this perspective, measuring the area covered by fresh concrete is particularly easy. It is also particularly easy to check whether the fresh concrete is spreading isotropically on the test surface.

[0023] In another particularly advantageous embodiment, the test surface is moistened before the fresh concrete is applied. Using at least one image of the test surface and / or the sensor, it is checked that the water loading of the test surface is within a specified target range.

[0024] The previous standard for the slump test stipulates that the test surface be moistened and the resulting water film then removed to make the test surface slightly damp. Compliance with this boundary condition is important to ensure that the results of the slump test are not distorted. A quantitative control is now being introduced, which further improves the reproducibility of the measured parameter for the consistency of the fresh concrete.

[0025] In another particularly advantageous embodiment, the characteristic for the consistency of the fresh concrete is logged in association with the batch of fresh concrete. "In association with the batch" in this context means that the information can be assigned to the batch, for example, it can be looked up under a batch name. Logging can be done, for example, in a database on a server, but also decentrally via a blockchain.

[0026] The improved measurement accuracy in determining the consistency parameter achieved with the method described above makes this parameter more meaningful not only for direct use on the construction site, but also for root cause analysis in cases where the consistency deviates from a desired value. If sufficient experience is gained regarding the consistencies of different batches, conclusions can be drawn, for example, using machine learning, which in turn can be used to better control the production of fresh concrete.

[0027] It is particularly advantageous to additionally record parameters that characterize the material composition of the fresh concrete in association with the batch of fresh concrete. This allows, for example, to determine whether the consistency of the fresh concrete can be reproducibly controlled via the material composition or whether this control is at least partially overridden by other influences.

[0028] It is also advantageous to record a target value for the consistency parameter, determined by the intended use of the fresh concrete, in association with the fresh concrete batch. This allows for an even more precise analysis of the extent to which a specified consistency target can be reproducibly achieved during the fresh concrete production process. In particular, it reveals whether, for example, a change in the material composition always has the intended effect.

[0029] It is also advantageous to record the ambient temperature and / or other weather conditions associated with the batch of fresh concrete. These other weather conditions can include, for example, air pressure and / or humidity. This allows for investigation into the extent to which weather conditions influence the consistency of the fresh concrete. This, in turn, allows for deduction of how the production of the fresh concrete can be adapted to the weather influences in order to achieve a specified consistency of the fresh concrete.

[0030] Once a wealth of experience has been recorded covering a sufficiently large number of batches, an artificial neural network (ANN), for example, can be trained to predict the actual value of this parameter based on the material composition of the fresh concrete in conjunction with the desired consistency parameter and the weather conditions. This training can be carried out, for example, as supervised training. This means that for each combination of material composition, weather conditions, and desired consistency occurring in the wealth of experience, a consistency prediction is determined using the ANN and compared with the actual consistency according to the wealth of experience. The ANN is then adjusted so that, on average, the actually measured values ​​of the consistency parameter are reproduced.

[0031] The improved measurement accuracy in determining the actual consistency parameter thus enables the ANN to more accurately predict the actual behavior of the fresh concrete. Accordingly, the generalization of the prediction to unknown situations—that is, to unknown combinations of material composition, weather conditions, and desired consistency—will also work better.

[0032] Once the ANN has been trained, it can be used to adapt the production of fresh concrete from the outset so that the fresh concrete is more likely to have exactly the intended consistency.

[0033] For example, the ANN can learn from the aforementioned experience that a combination of high temperature and low humidity tends to make the fresh concrete more viscous, and that this tendency can be counteracted by the simultaneous addition of water and another aggregate.

[0034] As explained above, the aim of improving the measurement accuracy in determining the parameter for the consistency of fresh concrete is to enable countermeasures to a certain extent and thus to "rescue" a delivery of fresh concrete that does not fully meet the specifications, rather than having to dispose of it as waste.

[0035] Therefore, the invention also relates to a method for controlling the flowability and / or the use of fresh concrete.

[0036] In this method, a consistency parameter is measured for a test batch of fresh concrete using the method described above. The measured parameter is compared with a target value specified for the intended use of the fresh concrete.

[0037] If the deviation from the target value does not exceed a specified tolerance threshold, the fresh concrete can still be used for its intended purpose. However, if the tolerance threshold is exceeded, a check is carried out to determine whether the fresh concrete can be treated in such a way that, after treatment, the parameter no longer deviates from the target value by more than the tolerance threshold.

[0038] If this test shows that the deviation can be reduced below the tolerance threshold through treatment, the treatment is then carried out. With the deviation now below the tolerance threshold, the fresh concrete can still be used for its intended purpose. It is recommended to measure the consistency parameter again as described above to ensure that the treatment was indeed successful.

[0039] However, if the test reveals that the deviation cannot be reduced below the tolerance threshold despite treatment, the fresh concrete is rejected for its intended use. Treatment may potentially make the fresh concrete suitable for another purpose on the construction site. Alternatively, it can be returned to the supplier in its unaltered form.

[0040] The examination of whether the deviation can be reduced below the tolerance threshold through treatment can, for example, also include an examination of whether the use of the subsequently treated fresh concrete is even permissible for the intended purpose on the construction site. If the consistency of the fresh concrete does not correspond to the specification for the intended use, this ultimately means that the composition of the fresh concrete is not what it should be. In other words, the deviating consistency is more or less a symptom of the underlying problem: that the composition is incorrect. There are many ways to adjust the consistency of fresh concrete retrospectively through treatment. However, not every such treatment gives the fresh concrete, or the concrete subsequently cured from it, all the properties that concrete mixed with the correct composition would have had from the outset.Therefore, for example, there may be specifications stating that certain parts that are particularly important for the stability of the building to be constructed may only be made from fresh concrete, which has the correct consistency from the outset without any subsequent treatment. This information can be obtained, for example, from a three-dimensional model of the building to be constructed, which is enriched with information about the planned statics of the building.

[0041] In a particularly advantageous embodiment, the maximum variability of the consistency of the fresh concrete through treatment is determined using the fresh concrete recipe. This recipe determines, in particular, the extent and direction in which the stoichiometry of the fresh concrete can be changed without losing important properties.

[0042] In a particularly advantageous embodiment, the treatment involves adding an additive that increases the flowability of the fresh concrete. For example, in response to the test batch of fresh concrete not being sufficiently flowable, a dosing device can be activated to add the additive to the remaining portion of the fresh concrete, or to a portion of that portion.

[0043] In a further advantageous embodiment, in response to the fact that the fresh concrete is not suitable for the intended use, it is checked whether an alternative use exists on the same construction site for which the fresh concrete is suitable, given its current value of the consistency parameter and / or a value of the parameter that can be achieved through treatment based on this. In response to the fact that such an alternative use does not exist, or does not exist to a sufficient extent (e.g., only for a small portion of the delivered quantity), a rejection of the delivery of the fresh concrete is triggered. This rejection can then manifest itself, for example, in the vehicle delivering the fresh concrete being directed back to the supplier.

[0044] In another particularly advantageous embodiment, in response to the fresh concrete, possibly after treatment, being suitable for a specific use (i.e., the originally intended use or an alternatively identified use) based on the consistency parameter, at least one conveying device for the fresh concrete is controlled to deliver the fresh concrete to this use. This conveying device can, for example, be a concrete swivel arm. It is also possible, for example, to change the billing for the fresh concrete depending on the use for which the fresh concrete is suitable. The information regarding which batch of fresh concrete was used where can, for example, be fed back to a Building Information Model (BIM). The BIM is a "digital twin" of the building to be constructed.If the information about which concrete was used where is fed back into the BMI, it can be used later to determine whether the construction was carried out correctly with regard to stability and durability. If defects are discovered, building components can be subjected to special inspections or regular inspection intervals can be shortened.

[0045] The described methods can be fully or partially computer-implemented. For example, an image of the test area can be created using a smartphone and then directly examined with a corresponding app for the spread of the fresh concrete. Therefore, the invention also relates to a computer program with machine-readable instructions that, when executed on one or more computers and / or mobile devices, cause the computers or mobile devices to carry out one of the described methods. The invention also relates to a machine-readable data carrier and / or a downloadable product containing the computer program.

[0046] According to the above description, the invention also relates to a device for determining the consistency of fresh concrete. This device comprises a test surface onto which the fresh concrete can be applied. The test surface is designed in such a way that the fresh concrete spreads over the test surface when the test surface is shaken. It is now at least one electromechanical, electromagnetic, pneumatic and / or hydraulic actuator for the vibration of the test surface and / or at least one sensor coupled to the test surface for the direct or indirect measurement of the coverage of the test surface with the fresh concrete provided.

[0047] As previously explained, these measures, either individually or in combination, make the determination of consistency significantly more reproducible and the obtained values ​​more meaningful. This is particularly advantageous when further conclusions are to be drawn from the data using machine learning or other analysis techniques.

[0048] At least one electromechanical, pneumatic, and / or hydraulic actuator for lifting the test surface and at least one electromagnetic actuator for abruptly dropping the test surface are provided. This allows the test surface to be lifted smoothly, for example, so that it is only subjected to a precisely defined vibration when dropped.

[0049] In a further advantageous embodiment, at least one sensor is designed as a pressure sensor, and / or as an optical sensor, and / or as a capacitive sensor. These sensors are particularly suitable for detecting the coverage of the test area with fresh concrete in a spatially resolved and, optionally, also time-resolved manner.

[0050] In particular, the device can be equipped with interfaces for transferring the recorded data to a blockchain, a building information model, BIM, or another protocol. Special description section

[0051] The subject matter of the invention is explained below with reference to figures, without limiting the subject matter of the invention. It is shown: Figure 1 : Embodiment of the method 100 for determining consistency; Figure 2 : Exemplary automation of shaking 120; Figure 3: Example sensory detection of the coverage 12 of the test area 1 with the fresh concrete 2; Figure 4 : Determination of the coverage 12 of the test area 1 with the fresh concrete 2 from a figure 1a of the test area 1; Figure 5 : Embodiment of the method 200 for controlling the flowability and / or the use of fresh concrete 2.

[0052] Figure 1 shows an embodiment of the method 100 for determining a parameter 21 for the consistency of fresh concrete 2. In the optional step 105, a test surface 1 is first moistened, and in the optional step 106 it is checked that the loading of the test surface 1 with water is within a predetermined target range.

[0053] In step 110, a predetermined amount of fresh concrete 2 is applied to the test surface 1. In step 120, the test surface is vibrated according to a predetermined time program, whereby, according to block 121, one or more electromechanical, electromagnetic, pneumatic, and / or hydraulic actuators 16a, 16b; 17a, 17b can be used for this purpose.

[0054] In step 130, the coverage 12 of the test area with the fresh concrete 2 is recorded. Various options for this are shown in box 130.

[0055] According to block 131, not only a static state of the occupancy 12 can be recorded, but also the temporal progress of this occupancy 12 can be tracked.

[0056] According to block 132, the occupancy 12 can be detected with one or more pressure sensors, with one or more optical sensors, and / or with one or more capacitive sensors. It is then not necessary to create an image 1a of the test area 1.

[0057] According to block 133, when determining the coverage 12 from a figure 1a, pixels of this figure 1a can be classified as to whether they belong to the free test area 1 or to the fresh concrete on it.

[0058] According to block 134, a parameterized approach 2a for the shape of the fresh concrete 2 located on the test area 1 can be adapted to the figure 1a of the test area 1 in such a way that contradictions with this figure 1a are minimized.

[0059] According to block 135, the figure 1a of the test area 1 can be transformed perspectively into a vertical view 1a of the test area 1. This makes it easier to determine, in particular, the area portion occupied by fresh concrete 2 on the test area 1.

[0060] From the coverage 12 of the test area 1 with the fresh concrete 2, the parameter 21 for the consistency of the fresh concrete 2 is evaluated in step 140.

[0061] In step 150, the parameter 21 thus determined is recorded in association with the batch 50 of the fresh concrete 2 in a protocol 60.

[0062] In step 160, additional parameters 22, which characterize the material composition of the fresh concrete 2, are recorded in the protocol 60 in association with the batch 50 of the fresh concrete 2.

[0063] In step 170, a target value 21a of the parameter 21, which is predetermined by the intended use of the fresh concrete 2, is additionally recorded in the protocol 60 in association with the batch 50 of the fresh concrete 2.

[0064] In step 180, the ambient temperature 31 and / or other weather conditions (here air pressure 32 and air humidity 33) are additionally recorded in the protocol 60 in association with the batch 50 of the fresh concrete 2.

[0065] Figure 2 shows, in a simplified schematic drawing not to scale, an exemplary possibility of how the shaking 120 of the test area 1 can be automated. This makes the shaking more reproducible, so that the accuracy of the ultimately obtained characteristic 21 for consistency can be further improved.

[0066] The test surface 1 is located on top of a movable plate 18, which is movable relative to a base body 19. With the pneumatic bellows 16a and 16b, the movable plate 18, and thus also the test surface 1 with the fresh concrete 2, can be lifted smoothly until it strikes the two electromagnets 17a and 17b. Figure 2 In the state shown, the fresh concrete 2 has just been applied to the test surface 1 and no vibration of the test surface 1 has yet occurred.

[0067] Electromagnets 17a and 17b are energized, thus holding movable plate 18. To prepare for the vibration of test surface 1, pneumatic bellows 16a and 16b are vented so that they do not slow the fall of movable plate 18. Electromagnets 17a and 17b are then simultaneously deactivated. The movable plate 18 then falls back onto the base body 19 in a precisely defined manner, so that test surface 1 with fresh concrete 2 is vibrated in a reproducible manner, and the fresh concrete 2 spreads accordingly across test surface 1.

[0068] Figure 3 shows in a simplified schematic drawing not to scale a possibility of measuring the coverage 12 of the test area 1 with the fresh concrete 2 by a sensor 1b.

[0069] The test surface 1 is located on top of a non-conductive plate 15a. The sensor 1b is a spatially resolved capacitive sensor and comprises two crossed arrays 15b and 15d of parallel wires separated by an adhesive layer 15c. Adjacent to this is another non-conductive plate 15e. The non-conductive plates 15a and 15e can be made of glass, for example, but can also be made of more robust non-conductive materials for use on construction sites, such as Plexiglas, acrylic glass, or plastic.

[0070] When fresh concrete 2 is present on test surface 1, the mutual capacitance of wires crossing at this point below test surface 1 changes. By testing the mutual capacitances of crossing wires, it is possible to determine, spatially resolved and without moving parts, which portion of test surface 1 is occupied by fresh concrete 2.

[0071] Figure 4shows, in a schematic drawing not to scale, how the coverage 12 of test area 1 with fresh concrete can be obtained from a figure 1a of test area 11. A parameterized approach 2a for the shape of the fresh concrete on test area 1 is adapted to figure 1a of test area 1 by varying the parameters in such a way that contradictions with figure 1a are minimized.

[0072] In the Figure 4 In the example shown, the parameterized approach 2a describes an ellipse with semi-major axis a and semi-minor axis b, which can also be rotated by an angle Θ.

[0073] Figure 5 shows an exemplary flow diagram of the method 200 with which the flowability and / or the use of fresh concrete 2 can be controlled.

[0074] In step 210, a characteristic 21 for the consistency of the fresh concrete 2 is measured using the previously described method 100. In step 220, the measured characteristic 21 is compared with a target value 21a specified for the intended use of the fresh concrete 2.

[0075] In step 230, it is checked whether the deviation Δ of the measured parameter 21 from the target value 21a exceeds a tolerance threshold. If this is not the case (truth value 0), a conveyor can be directly controlled in step 290a so that the fresh concrete 2 is fed to its intended use.

[0076] If, however, the tolerance threshold is exceeded (truth value 1 in step 230), a check is carried out in step 240 to determine whether the deviation Δ can be reduced below the tolerance threshold by treating the fresh concrete 2. If this is the case (truth value 1), the treatment of the fresh concrete 2 is carried out in step 250. Subsequently, in step 290a, the conveyor is controlled so that the fresh concrete 2 is fed to its intended use.

[0077] If, however, the deviation Δ cannot be reduced below the tolerance threshold even by treating the fresh concrete 2 (truth value 0 in step 240), the fresh concrete 2 is blocked for the intended use in step 260. A check is then carried out in step 270 to determine whether an alternative use exists on the same construction site for which the fresh concrete 2 can be used either in its current state or after treatment. If this is the case (truth value 1), treatment 250 is carried out, if necessary. Subsequently, in step 290b, the conveyor is controlled so that the fresh concrete 2 is fed to its alternative use.

[0078] However, if no alternative use exists (truth value 0 at step 280), a rejection of the delivery of fresh concrete 2 is triggered. List of reference symbols

[0079] 1Test area 1aImage of test area 1 1a'Vertical view, generated from Figure 1a 1bSensor connected to test area 1 12Covering of the test area with fresh concrete 2 15a, 15ePlates made of non-conductive material 15b, 15dLayers of parallel wires, offset by 90° to each other 15cAdhesive layer between layers 15b, 15d 16a, 16bPneumatic bellows, lift movable plate 18 17a, 17bElectromagnets, hold movable plate 18 18Movable plate with test area 1 19Base body 2Fresh concrete 2aParameterized approach for the shape of fresh concrete 2 21Parameter for the consistency of fresh concrete 2 21aTarget value for parameter 21 22Parameters for the material composition of fresh concrete 2 31Temperature 32Air pressure 33Humidity 50Batch of fresh concrete 2 60Protocol 100Procedure for determining parameter 21 for consistency 105Moistening test area 1 106Checking the water loading of test area 1 110Application of fresh concrete 2 to test area 1 120Vibrating theTest area 1 121 Vibration using actuators 130 Recording the coverage 12 of test area 1 with fresh concrete 2 131 Recording the temporal progress of coverage 12 132 Recording coverage 12 with sensors 133 Classifying pixels of Figure 1a 134 Adapting approach 2a to Figure 1a 135 Transforming Figure 1a to the vertical view 1a' 140 Evaluating parameter 21 from coverage 12 150 Recording parameter 21 for consistency 160 Recording parameter 22 for material composition 170 Recording the target value 21a for parameter 21 180 Recording weather influences 31, 32, 33 200 Methods for controlling flowability and / or use 210 Measuring parameter 21 220Comparison of parameter 21 with target value 21a 230Check whether deviation Δ is greater than tolerance threshold 240Check whether treatment of fresh concrete 2 is effective 250Treatment of fresh concrete 2 260Blocking of fresh concrete 2 for intended use 270Check forAlternative use for fresh concrete 2 280 Triggering a rejection of the delivery of fresh concrete 2 290aSupply for intended use with conveyor 290bSupply for alternative use with conveyor aMajor semi-axis of the ellipse forming shape 2a bMinor semi-axis of the ellipse ΘAngle of rotation of the ellipse ΔDeviation

Claims

1. A method (100) for determining the consistency of fresh concrete (2), having the following steps: • a predefined quantity of the fresh concrete (2) is applied (110) to a test area (1); • the test area (1) is shaken (120) in accordance with a predefined time program, wherein the test area (1) is arranged on an upper side of a movable plate (18) which can be moved relative to a base body (19), and wherein the movable plate (18) with the test area (1) is raised smoothly from the base body (19) by means of at least one electromechanical, pneumatic and / or hydraulic actuator (16a, 16b) for the shaking up to at least one electromagnetic actuator (17a, 17b), and is dropped jerkily onto the base body (19) by means of the at least one electromagnetic actuator (17a, 17b); • the coverage (12) of the test area (1) with the fresh concrete (2) is captured (130) from at least one image (1a) of the test area (1), as well as optionally additionally by at least one sensor (1b) coupled to the test area (1), and wherein optionally during and / or after the shaking (120), the temporal progress of the coverage (12) of the test area (1) with the fresh concrete (2) is captured (131) from multiple images (1a) of the test area (1) and / or from a temporal sequence of measured values of the at least one sensor (1b); • a characteristic (21) for the consistency of the fresh concrete (2) is evaluated (140) from the coverage (12), wherein pixels of the image (1a) of the test area (1) are classified (133) as to whether they belong to the free test area (1) or to the fresh concrete (2) located thereon, and the proportion of the test area (1) which is covered by fresh concrete (2) is assessed as a characteristic (21) of the fresh concrete (2).

2. The method (100) according to Claim 1, wherein the coverage (12) of the test area (1) with the fresh concrete (2) is captured (132) with one or more pressure sensors, with one or more optical sensors, and / or with one or more capacitive sensors.

3. The method (100) according to any one of Claims 1 to 2, wherein the image (1a) of the test area (1) is transformed (135) in perspective to a vertical view (1a') of the test area (1).

4. The method (100) according to any one of Claims 1 to 3, wherein the test area (1) is moistened (105) prior to the application (110) of the fresh concrete (2) and wherein it is checked (106), based on at least one image (1a) of the test area (1) and / or by means of the sensor (1b), that the loading of the test area (1) with water lies in a predefined nominal range.

5. A method (200) for controlling the flowability and / or the use of fresh concrete (2) having the following steps: • a characteristic (21) for the consistency for a test quantity of the fresh concrete (2) is measured (210) with the method (100) according to any one of Claims 1 to 4; • the measured characteristic (21) is compared (220) with a predefined nominal value (21a) for the intended use of the fresh concrete (2); • in response to the finding (230) that the deviation Δ of the measured characteristic (21) from the nominal value (21a) exceeds a tolerance threshold, it is checked (240) whether the fresh concrete (2) can be treated such that, following the treatment, the characteristic (21) no longer deviates from the nominal value (21a) by more than the tolerance threshold, wherein optionally o a maximum variability of the consistency of the fresh concrete (2) is determined by treatment utilizing the formulation of the fresh concrete (2), and / or o an addition of an additive which increases the flowability of the fresh concrete (2) is selected as the treatment; • if the check (240) shows that the deviation Δ can be lowered below the tolerance threshold by the treatment, then the treatment is performed (250); • if the check (240) shows that the deviation Δ cannot be lowered below the tolerance threshold despite treatment, the fresh concrete (2) is blocked (260) for the intended use.

6. The method (200) according to Claim 5, wherein • in response to the fact that the fresh concrete (2) is blocked (260) for the intended use, the accounting for the fresh concrete (2) is amended, and / or it is checked (270) whether an alternative use exists on the same construction site, for which the fresh concrete (2) is suitable in view of its current value of the characteristic (21) for the consistency, and / or in view of a value of the characteristic (21) which can be achieved proceeding herefrom by treatment, and wherein a rejection of the delivery of the fresh concrete (2) is triggered (280) if the alternative use is not available or is not available to a sufficient extent, and / or • in response to the fact that the fresh concrete (2), possibly after treatment, is suitable for a use in view of the characteristic (21) for the consistency, at least one conveying device for the fresh concrete (2) is actuated (290a, 290b) in that it feeds the fresh concrete (2) to this use.

7. A device for determining the consistency of fresh concrete (2), comprising a test area (1), to which the fresh concrete (2) can be applied, wherein the condition of the test area (1) is such that the fresh concrete (2) spreads on the test area (1) when the test area (1) is shaken, and wherein the test area (1) is arranged on an upper side of a movable plate (18) which can be moved relative to a base body (19), wherein • at least one electromechanical, electromagnetic, pneumatic and / or hydraulic actuator (16a, 16b; 17a, 17b) is provided for shaking the test area, characterized in that • at least one electromechanical, pneumatic and / or hydraulic actuator (16a, 16b) is provided for raising the movable plate (18) with the test area (1), and at least one electromagnetic actuator (17a, 17b) is provided for jerkily dropping the movable plate (18) with the test area (1) onto the base body (19).

8. The device according to Claim 7, wherein at least one sensor (1b) is additionally provided that is coupled to the test area (1) for directly or indirectly measuring the coverage (12) of the test area (1) with the fresh concrete .

9. The device according to Claim 8, wherein at least one sensor (1b) is configured as a pressure sensor, and / or as an optical sensor (1b), and / or as a capacitive sensor (1b).