A coring device for road construction quality inspection

Abstract

The present invention relates to the technical field of pavement sampling, and in particular to a coring device for road construction quality inspection. The device comprises a speed regulating mechanism, which comprises a data acquisition module, a speed regulating analysis module and a regulating module; the data acquisition module is used to collect the pressure value and displacement in the coring process and transmit them to the speed regulating analysis module, which is used to determine the initial speed through the displacement, and determine the stratification moment according to the change in the pressure value; the distribution between the current pressure value and displacement after the stratification moment and the stratification moment is analyzed to obtain the road hardness change and the core sample connection shearing force, and the speed adjustment amount is obtained in combination with the speed and pressure changes at the previous moment and input into the regulating module for adjustment. The present invention takes into account the influence on the stratified part of the core sample during the coring process and adaptively adjusts the speed, so that the running coring speed can complete the work more efficiently while ensuring the quality of the core sample, thereby improving the quality of subsequent inspections.

Description

Technical Field

[0001] The invention relates to the technical field of pavement sampling, and in particular to a coring device for detecting pavement construction quality. Background Art

[0002] Pavement coring device is a professional equipment, mainly used to drill core samples from the road surface for quality and structural analysis. Pavement coring device is widely used in road construction, maintenance, repair and scientific research. It can help understand the structure, materials and performance of the road, detect road flatness, strength and other indicators, diagnose road surface diseases and support the research of new technologies and processes for road materials.

[0003] Pavement coring devices mainly work through drilling technology, using a high-speed rotating drill bit to drill core samples on the road surface. The drill bit is usually made of high-strength, high-wear-resistant alloy steel or hard alloy, and is equipped with a cooling system to prevent the drill bit from overheating. Current pavement coring devices mostly use the traditional high-speed rotary coring method, which performs well on hard pavement, but has obvious shortcomings on soft or newly paved pavement. Especially in the coring process of soft pavement with obvious stratification or newly paved pavement, due to the low shear strength of the pavement material, the inappropriate drill bit speed can easily cause the core sample to break or break during the extraction process, affecting the accuracy of the core sample detection and increasing the detection cost and time of the construction. Summary of the invention

[0004] In order to solve the technical problem in the prior art that the inappropriate drill bit speed easily causes the core sample to be broken or crushed during the extraction process, the purpose of the present invention is to provide a coring device for road construction quality inspection, and the technical solution adopted is as follows:

[0005] The present invention provides a coring device for road construction quality inspection, the main body includes a connecting tube and a sampling barrel, the main body also includes a speed regulating mechanism, the speed regulating mechanism includes a data acquisition module, a speed regulating analysis module and a regulating module;

[0006] The signal output end of the data acquisition module is connected to the signal input end of the speed regulation and analysis module, and the signal output end of the speed regulation and analysis module is connected to the signal input end of the regulation module; the regulation module is used to control the speed of the coring device;

[0007] The data acquisition module is used to collect the pressure value during the coring process through the pressure sensor on the connecting tube, and collect the displacement and initial compaction displacement during the coring process through the encoder on the sampling barrel; the pressure value and displacement at each sampling moment during the coring process, as well as the initial compaction amount are transmitted to the speed regulation and analysis module;

[0008] The speed adjustment and analysis module is used to determine the starting speed of the coring process according to the initial compaction displacement; during the coring process, the delamination time is determined according to the significance of the pressure value change in the time series;

[0009] After the delamination moment, the road hardness change degree at the current sampling moment is obtained according to the distribution difference between the pressure value change degree and displacement amount in the time series before the current sampling moment and the delamination moment; the core sample joint shear stress at the current sampling moment is obtained according to the proximity between the pressure value change degree and displacement amount at the current sampling moment and the delamination moment;

[0010] After the stratification moment, according to the pressure value change at the current sampling moment, the sudden change of road hardness and the shear stress of the core sample connection, combined with the speed at the previous sampling moment in the time sequence, the speed adjustment value at the current sampling moment is obtained;

[0011] The speed adjustment amount is input into the regulation module to adjust the speed at the current sampling moment.

[0012] Furthermore, the method for obtaining the road hardness variation degree includes:

[0013] Before the current sampling moment, the variation deviation of each sampling moment is obtained according to the deviation degree of the pressure value and the proximity degree of the displacement between each sampling moment and the stratification moment;

[0014] The road hardness variation at the current sampling moment is obtained by combining the variation deviations at all sampling moments before the current sampling moment.

[0015] Furthermore, the method for obtaining the change deviation includes:

[0016] For any sampling time before the current sampling time, the difference between the pressure value at the stratification time and the pressure value at the sampling time is taken as the pressure deviation at the sampling time;

[0017] A negative correlation mapping is performed on the difference between the displacement at the sampling moment and the displacement at the stratification moment to obtain the distribution reliability at the sampling moment;

[0018] The pressure deviation at the sampling moment is combined with the distribution confidence to obtain the variation deviation at the sampling moment.

[0019] Furthermore, the method for obtaining the core sample joint shear stress includes:

[0020] According to the difference between the pressure value change at the stratification moment and the current sampling moment, the mutation tolerance index at the current sampling moment is obtained;

[0021] According to the proportion of the displacement at the delamination moment in the displacement at the current sampling moment, the distance tolerance index at the current sampling moment is obtained;

[0022] The core sample connection shear stress at the current sampling moment is obtained by combining the mutation bearing index and the distance bearing index at the current sampling moment.

[0023] Furthermore, obtaining the mutation tolerance index at the current sampling moment according to the difference between the pressure value change at the stratification moment and the current sampling moment includes:

[0024] The difference between the pressure value at the stratification moment and the pressure value at the previous sampling moment in the time series is taken as the pressure mutation degree;

[0025] The difference between the pressure value at the current sampling moment and the pressure value at the previous sampling moment in time series is taken as the degree of change at the current sampling moment;

[0026] The difference between the change degree at the current sampling moment and the pressure mutation degree is negatively correlated and mapped as the mutation tolerance index at the current sampling moment.

[0027] Furthermore, the method for obtaining the speed adjustment amount includes:

[0028] The product of the sudden change of road hardness at the current sampling moment and the shear stress of the core sample connection is negatively correlated and normalized to obtain the adjustment correction coefficient at the current sampling moment;

[0029] According to the change degree between the pressure value at the current sampling moment and the pressure value at the previous sampling moment in the time series, combined with the speed at the previous sampling moment in the time series, the initial speed adjustment degree at the current sampling moment is obtained;

[0030] The product of the initial speed adjustment degree at the current sampling moment and the adjustment correction coefficient is used as the speed adjustment amount at the current sampling moment.

[0031] Further, the initial speed adjustment degree at the current sampling moment is obtained based on the change degree between the pressure value at the current sampling moment and the pressure value at the previous sampling moment in the time sequence, combined with the speed at the previous sampling moment in the time sequence, including:

[0032] The difference between the pressure value at the current sampling moment and the pressure value at the previous sampling moment in time series, and the ratio of the pressure value at the previous sampling moment, are used as the adjustment coefficient at the current sampling moment;

[0033] The product of the adjustment coefficient at the current sampling moment and the rotation speed at the previous sampling moment in time sequence is used as the initial rotation speed adjustment degree at the current sampling moment.

[0034] Furthermore, inputting the speed adjustment amount into the regulating module to regulate the speed at the current sampling moment includes:

[0035] The sum of the speed adjustment at the current sampling moment and the speed at the previous sampling moment in the time sequence is used as the adjustment speed at the current sampling moment;

[0036] When the adjusted speed is less than or equal to the preset upper speed limit, the speed at the current sampling moment is the adjusted speed; when the adjusted speed is greater than the preset upper speed limit, the speed at the current sampling moment is the preset upper speed limit.

[0037] Further, the method of determining the starting rotation speed of the coring process according to the initial compaction displacement includes:

[0038] When the initial compaction displacement is less than the preset initial maximum displacement, the ratio of the initial compaction displacement to the preset initial maximum displacement is used as the adjustment ratio; the difference between the preset upper speed limit and the preset lower speed limit is used as the adjustment range;

[0039] The product of the adjustment ratio and the adjustment range is used as the initial adjustment amount; the difference between the preset upper speed limit and the initial adjustment amount is calculated as the starting speed of the coring process;

[0040] When the initial compaction displacement is greater than or equal to the preset initial maximum displacement, the preset rotation speed lower limit is used as the rotation speed for starting the coring process.

[0041] Furthermore, during the coring process, determining the delamination time according to the significance of the pressure value change in the time series includes:

[0042] The pressure value difference between each two adjacent sampling moments in the time sequence before the current sampling moment is taken as the pressure value change degree, and all the pressure value change degrees are sorted in time sequence to obtain the pressure value change sequence at the current sampling moment;

[0043] The difference between the last two pressure value change degrees in the pressure value change sequence is used as the pressure change index at the current sampling moment; except for the last pressure value change degree in the pressure value change sequence, the difference between the change degrees of every two adjacent pressure values ​​in the pressure value change sequence is calculated and the maximum value of all the differences is used as the extreme value of change at the current moment;

[0044] When the pressure change index at the current sampling moment is greater than the extreme value of the change, the current sampling moment is taken as the stratification moment.

[0045] The present invention has the following beneficial effects:

[0046] The present invention determines the initial rotation speed of coring by the initial compaction displacement, considers the softening layer of the road surface, avoids the core sample being broken due to the initial rotation speed being fast enough, and then determines the stratification time by the change of the pressure value. In the process of accelerating and efficiently coring after the softening layer, the possibility of the core sample being broken due to the influence of shear force caused by the excessive acceleration is further considered. After the stratification time, the distribution between the pressure value and the displacement before the current moment and the stratification moment is analyzed to obtain the road hardness change and the core sample connection shearing strength. The adjustment and correction of the rotation speed is considered from the change of the hardness affected by different depths at the current moment and the possible degree of the influence of shear force on the stratified part, so as to further obtain the rotation speed adjustment amount in combination with the pressure change and the rotation speed at the previous moment, and adjust the rotation speed more appropriately. The present invention considers the influence of the stratified part of the core sample during the initial selection and subsequent adjustment of the rotation speed of the coring device, and adaptively adjusts the rotation speed, so that the operation of the coring speed can complete the work more efficiently while ensuring the quality of the core sample, thereby improving the quality of subsequent detection. BRIEF DESCRIPTION OF THE DRAWINGS

[0047] In order to more clearly illustrate the technical solutions and advantages in the embodiments of the present invention or the prior art, the drawings required for use in the embodiments or the prior art descriptions are briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0048] Figure 1 A structural diagram of a coring device for road construction quality inspection provided by one embodiment of the present invention;

[0049] Figure 2 A flow chart of a rotation speed adjustment method for a coring device provided by one embodiment of the present invention;

[0050] Figure 3 A flow chart of a method for obtaining the shear stress of a core sample connection provided by an embodiment of the present invention;

[0051] In conjunction with the accompanying drawings, the following reference numerals are marked on the drawings: 1-vertical pole; 2-sliding seat; 3-driver; 4-connecting tube; 5-sleeve tube; 6-sampling barrel; 7-connecting seat; 8-welding seat; 9-connecting rod; 10-positioning ring; 11-electric wire; 12-fixed block. DETAILED DESCRIPTION

[0052] In order to further explain the technical means and effects adopted by the present invention to achieve the predetermined invention purpose, the following is a detailed description of the specific implementation, structure, features and effects of a coring device for road construction quality inspection proposed by the present invention in combination with the accompanying drawings and preferred embodiments. In the following description, different "one embodiment" or "another embodiment" does not necessarily refer to the same embodiment. In addition, specific features, structures or characteristics in one or more embodiments may be combined in any suitable form.

[0053] Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs.

[0054] The following is a detailed description of a specific scheme of a coring device for road construction quality inspection provided by the present invention in conjunction with the accompanying drawings. Figure 1 , which shows a structural diagram of a coring device for road construction quality inspection provided by an embodiment of the present invention, the coring device includes: 1-vertical pole; 2-sliding seat; 3-driver; 4-connecting tube; 5-sleeve tube; 6-sampling barrel; 7-connecting seat; 8-welding seat; 9-connecting rod; 10-positioning ring; 11-electric wire; 12-fixed block, and also includes a speed adjustment mechanism, the speed adjustment mechanism includes a data acquisition module, a speed adjustment analysis module and an adjustment module, which is used to adjust the speed of the real-time coring device.

[0055] The data acquisition module collects the pressure values ​​of the coring device and the road surface through the pressure sensor installed on the connecting tube 4, and collects the displacement of the sampling barrel during the coring process through the encoder installed on the sampling barrel 6. Before the coring process, it is necessary to select a flat and clean road surface to install the coring device, and the sampling barrel 6 needs to contact and compact the ground. In the embodiment of the present invention, after the sampling barrel 6 contacts the ground and compacts, the compacted displacement is obtained as the initial compacted displacement to reflect the initial softness and hardness of the road surface. During the coring process, the pressure value and displacement at each sampling moment are collected at a preset sampling frequency, where the preset sampling frequency is set to 50Hz. The specific collection setting implementer can adjust it according to the specific implementation scenario, and there is no limitation here.

[0056] The collected pressure value and displacement are transmitted to the speed regulation and analysis module through the signal output end. The speed regulation and analysis module is used for data processing. The chip type is FPGA. It receives the signal from the data acquisition module to perform speed regulation analysis of the coring device, and transmits the signal after analysis to the regulation module for speed control.

[0057] The speed regulation analysis module performs speed regulation analysis on the coring device. Figure 2 , which shows a flow chart of a rotation speed adjustment method of a coring device provided by an embodiment of the present invention, the method comprising the following steps:

[0058] S1: The starting rotation speed of the coring process is determined according to the initial compaction displacement; during the coring process, the stratification moment is determined according to the significance of the pressure value change in the time series.

[0059] On soft or newly paved roads, the hardness of the softened layer of the road surface is lower. The displacement of the sampling barrel after contact with the ground and compaction reflects the initial hardness of the road surface. The greater the displacement of the sampling barrel after compaction on the ground, the smaller the initial hardness of the road surface. At this time, the road surface is softer. If the initial drill bit rotates faster, it may cause the core sample to break. Therefore, the larger the initial compaction displacement, the smaller the initial rotation speed of the coring device should be.

[0060] The starting rotation speed is determined by the initial compaction displacement. In an embodiment of the present invention, when the initial compaction displacement is less than the preset initial maximum displacement, it means that the displacement is within the allowable range of the maximum displacement. The ratio of the initial compaction displacement to the preset initial maximum displacement is used as the adjustment ratio. The larger the adjustment ratio, the lower the road surface hardness and the higher the rotation speed adjustment requirement.

[0061] The difference between the preset upper speed limit and the preset lower speed limit is further used as the adjustment range, that is, the range of the preset speed is used as the adjustment range. The product of the adjustment ratio and the adjustment range is used as the initial adjustment amount. The speed adjustment degree is quantified according to the hardness and softness of the road surface. The larger the initial adjustment amount, the higher the need for reduction.

[0062] Finally, the difference between the preset upper speed limit and the initial adjustment amount is calculated as the starting speed of the coring process, and the speed is adjusted down. And when the initial compaction displacement is greater than or equal to the preset initial maximum displacement, it is said that the road surface hardness is too small, and the coring is started directly at the minimum speed, and the preset lower speed limit is used as the starting speed of the coring process.

[0063] In a specific implementation of an embodiment of the present invention, when the pressure between the coring device and the road surface reaches a pressure threshold, the sampling barrel is considered to have been compacted, wherein the pressure threshold is preset to 100N, and the initial maximum displacement is preset to 1cm, and the lower limit of the rotation speed of the coring device is preset to 400r / min, and the upper limit of the rotation speed is preset to 1000r / min. The specific numerical settings are adjusted by the implementer according to the implementation scenario and are not limited here.

[0064] The core is taken at the initial rotation speed in the softened layer of the road surface to ensure stable sampling during the coring process. When the sampling barrel passes through the softened surface layer of the road surface, the probability of breakage during the drilling process is low. Therefore, the rotation speed needs to be increased to complete the coring work more efficiently. In order to facilitate subsequent adjustment and analysis, it is necessary to first determine the sampling time when stratification occurs.

[0065] Different depths of the road surface will result in different hardness of the material. For example, asphalt road surface will be softer under high temperature. The deeper the road surface, the weaker the temperature conduction, that is, the lower the temperature, the higher the material hardness and the higher the pressure value. In the stratified part of the softening layer, the hardness will change suddenly, and the pressure value will also change suddenly. Therefore, the stratification time is determined by the significant changes in the pressure value in the time series.

[0066] In one implementation of an embodiment of the present invention, the difference in pressure values ​​between each two adjacent sampling moments in the time series before the current sampling moment is taken as the pressure value change degree, and all pressure value change degrees are sorted in time series order to obtain the pressure value change sequence at the current sampling moment, and the sequence of pressure value change degrees in time series is obtained to facilitate subsequent analysis of the sudden change in the degree of change.

[0067] Furthermore, the difference between the last two pressure value change degrees in the pressure value change sequence is used as the pressure change index at the current sampling moment, reflecting the degree of deviation of the pressure value change at the current moment.

[0068] Because the pressure change at the sampling moment is relatively stable before the stratification moment is determined, during the judgment and analysis, except for the last pressure value change in the pressure value change sequence, the difference between the change degrees of every two adjacent pressure values ​​in the pressure value change sequence is calculated and the maximum value of all the differences is taken as the change extreme value at the current moment, reflecting the maximum allowable deviation value of the pressure value change during the stable change process.

[0069] When the pressure change index at the current sampling moment is greater than the change extreme value, and the difference between the pressure change index and the change extreme value is greater than the preset change threshold, it means that the deviation degree of the pressure value change at the current moment is extremely high, the stability change is destroyed, and the current sampling moment is used as the stratification moment.

[0070] In the embodiment of the present invention, considering that when the pressure change index is greater than the extreme value of the change, it is also possible that the pressure value change at the current sampling moment deviates from a high value, but the degree of deviation is small, and it is within the acceptable stable change fluctuation range. Therefore, the preset change threshold is further limited. In the embodiment of the present invention, it is set to the size of the extreme value of the change, that is, when the pressure change index is high and the degree of deviation is greater than the extreme value of the change, the stability is destroyed at this time, and the specific numerical value can be adjusted by the implementer by himself, and there is no restriction here.

[0071] After obtaining the stratification moment, the coring device can adjust the rotation speed to ensure efficient operation.

[0072] S2: After the stratification moment, the road hardness change degree at the current sampling moment is obtained according to the distribution difference between the pressure value change degree and displacement amount in the time series before the current sampling moment and the stratification moment; the core sample joint shear stress at the current sampling moment is obtained according to the proximity between the pressure value change degree and displacement amount at the current sampling moment and the stratification moment.

[0073] When the hardness of the road material varies greatly, if the rotation speed increases too quickly, the softened layer with lower hardness will be more affected by the shear force, which will easily cause breakage and crushing during the subsequent coring process, affecting the quality of the core sample. Therefore, it is necessary to correct and adjust the increase in rotation speed.

[0074] Among them, shear force is a force that hinders the sliding when two objects contact each other and try to slide relative to each other along the contact surface. When the shear force is large and exceeds the shear strength limit of the material, the core sample will be sheared, that is, it will be sheared along a certain plane. If some materials in the core sample are damaged or deformed due to excessive shear force, the structure of the entire core sample will be affected, which may cause its bearing capacity to decrease or fail, affecting the test results.

[0075] First, we analyze the change in hardness. When the hardness changes significantly, we need to consider the influence of shear force more. After the stratification moment, we get the degree of change based on the difference between the continuously changing pressure value and displacement at the current sampling moment and the stratification moment.

[0076] Preferably, in some possible implementation methods of the embodiments of the present invention, before the current sampling moment, the change deviation of each sampling moment is obtained based on the degree of deviation in pressure value and the proximity of displacement between each sampling moment and the stratification moment. The closer each sampling moment is to the stratification moment, the more the deviation in pressure can reflect the degree of difference in material change.

[0077] Therefore, in an embodiment of the present invention, for any sampling moment before the current sampling moment, the difference between the pressure value at the stratification moment and the pressure value at the sampling moment is first taken as the pressure deviation at the sampling moment. The greater the pressure deviation, the greater the hardness change during the coring process.

[0078] Furthermore, a negative correlation mapping is performed between the displacement at the sampling moment and the displacement at the stratification moment to obtain the distribution reliability of the sampling moment. The closer the sampling moment is to the stratification moment, the higher the contribution of the analysis of the difference change.

[0079] Finally, the pressure deviation at the sampling moment is combined with the distribution reliability to obtain the variation deviation at the sampling moment. In the embodiment of the present invention, the product of the pressure deviation at the sampling moment and the distribution reliability is used as the variation deviation at the sampling moment, and the distribution reliability is used as the weight of the pressure deviation analysis. When the variation deviation at the sampling moment is higher, it means that there is a higher hardness difference in the coring process, and more attention should be paid to the adjustment degree in the subsequent rotation speed adjustment.

[0080] Finally, the road hardness variation at the current sampling moment is obtained by combining the variation deviations at all sampling moments before the current sampling moment. In the embodiment of the present invention, the mean of the variation deviations at all sampling moments before the current sampling moment is taken as the road hardness variation at the current sampling moment, reflecting the degree of hardness variation difference of the entire core sample before the current sampling moment. The greater the road hardness variation, the greater the hardness variation difference, and the higher the degree of correction required.

[0081] Secondly, the shear force tolerance of the core sample is analyzed. When the shear force tolerance is greater, the possibility of the core sample being broken or damaged due to excessive growth rate is higher. For the current moment after the stratification moment, if the pressure change is closer to the significant change caused by stratification, it means that there is a moment of rapid hardness change at the current moment, and the overall shear force tolerance of the core sample is higher. Considering the fragility of the softening layer, the larger the proportion of the softening layer in the overall core sample, the greater the influence of shear damage that needs to be considered when increasing the speed.

[0082] Preferably, in some possible implementations of the present invention, the method for obtaining the core sample joint shearing force at the current sampling moment can be found in Figure 3 , which shows a flow chart of a method for obtaining the shear stress of a core sample connection provided by an embodiment of the present invention, the method comprising the following steps:

[0083] S211: Obtaining a mutation tolerance index at the current sampling moment according to the difference in pressure value change between the stratification moment and the current sampling moment.

[0084] First, we analyze the degree of pressure change. When the pressure value change is closer to the stratification, it means that there is a large hardness change at the coring position at the current moment, and the shear resistance of the core sample will be greater.

[0085] In the embodiment of the present invention, the difference between the pressure value at the delamination moment and the pressure value at the previous sampling moment in the time series is taken as the pressure mutation degree, and the difference between the pressure value at the current sampling moment and the pressure value at the previous sampling moment in the time series is taken as the change degree at the current sampling moment, and the degree of change between the two moment distributions and the previous pressure is obtained. The difference between the change degree at the current sampling moment and the pressure mutation degree is negatively correlated and mapped as the mutation tolerance index at the current sampling moment. The smaller the difference, the more significant the pressure change at the current moment, and the higher the shear tolerance.

[0086] In an embodiment of the present invention, the negative correlation mapping may be mapped in the form of a negative exponential power, reflecting that the mutation tolerance index increases as the difference decreases. It should be noted that negative correlation mapping is a technical means well known to those skilled in the art. For example, inverse proportional mapping may also be used, which is not limited here.

[0087] S212: Obtaining a distance tolerance index at the current sampling moment according to the proportion of the displacement at the delamination moment in the displacement at the current sampling moment.

[0088] Furthermore, from the distribution of the softened layer of the pavement, the higher the proportion of the softened layer in the core sample before the current sampling moment, the lower the degree of shear that the core sample can withstand during the coring process, and the higher the degree of adjustment and correction of the rotation speed. Therefore, in an embodiment of the present invention, the ratio of the displacement at the stratification moment to the displacement at the current sampling moment is used as the distance bearing index at the current sampling moment.

[0089] S213: Combining the mutation bearing index and the distance bearing index at the current sampling moment, obtaining the core sample connection shear bearing force at the current sampling moment.

[0090] Finally, the comprehensive analysis of pressure changes and position conditions is used to obtain the shear stress on the core sample connection at the current sampling moment, reflecting the degree of shear stress on the stratified part at the current sampling moment.

[0091] In an embodiment of the present invention, the product of the sudden change bearing index and the distance bearing index at the current sampling moment is used as the core sample connection shear bearing strength at the current sampling moment. When the sudden change bearing index and the distance bearing index are larger, it means that the pressure change affected by the material at the current sampling moment is higher, and the softening layer is distributed higher in the core sample. Therefore, the greater the core sample connection shear bearing strength, it reflects that the shear force degree borne by the layered part at this time is higher.

[0092] At this point, the analysis of how the rotation speed adjustment is affected by the core sample after the stratification moment is completed.

[0093] S3: After the stratification moment, according to the pressure value change at the current sampling moment, the sudden change in road hardness and the shear stress of the core sample connection, combined with the speed at the previous sampling moment in time sequence, the speed adjustment value at the current sampling moment is obtained.

[0094] During the coring process, the higher the pressure at the current sampling moment, the higher the rotation speed needs to be. However, considering the influence of shear force on the stratification, combined with the sudden change in road hardness and the correction of shear force on the core sample connection, a more accurate and appropriate rotation speed adjustment amount can be obtained.

[0095] Preferably, in some possible implementations of the embodiments of the present invention, the method for obtaining the speed adjustment amount includes:

[0096] First, the product of the sudden change of road hardness at the current sampling moment and the shear stress of the core sample connection is negatively correlated and normalized to obtain the adjustment correction coefficient at the current sampling moment. The greater the sudden change of road hardness, the higher the degree of impact on the core sample needs to be considered. The greater the shear stress of the core sample connection, the higher the shear stress of the core sample has been affected by the core sample, and the lower the correction increment result needs to be. Therefore, the adjustment correction coefficient is obtained in the form of negative correlation. It should be noted that the negative correlation mapping can be mapped in the form of negative exponents, and normalization is a technical means well known to those skilled in the art. The normalization option can be linear normalization or standard normalization, etc. The specific method is not limited here.

[0097] Furthermore, based on the degree of change between the pressure value at the current sampling moment and the pressure value at the previous sampling moment in time sequence, combined with the speed at the previous sampling moment in time sequence, the initial speed adjustment degree at the current sampling moment is obtained, and under normal circumstances, the speed increase is selected according to the pressure situation.

[0098] In the embodiment of the present invention, the difference between the pressure value at the current sampling moment and the pressure value at the previous sampling moment in the time sequence, and the ratio of the pressure value at the previous sampling moment, are used as the adjustment coefficient at the current sampling moment. The proportion of the change in the pressure value to the pressure value at the previous moment reflects the demand for the speed increment. The greater the difference in change, the higher the speed increment demand. Therefore, the product of the adjustment coefficient at the current sampling moment and the speed at the previous sampling moment in the time sequence is used as the initial speed adjustment degree at the current sampling moment, reflecting the speed increment degree obtained by the initial analysis.

[0099] Finally, the product of the initial speed adjustment degree and the adjustment correction coefficient at the current sampling moment is used as the speed adjustment amount at the current sampling moment. The correction coefficient is used for adjustment. When the correction coefficient is lower, the shearing condition is more significant, and the adjustment amount needs to be smaller to ensure the quality of the core sample.

[0100] At this point, the correction of the current rotation speed adjustment is completed, and a more reliable rotation speed adjustment amount is obtained.

[0101] S4: Input the speed adjustment amount into the adjustment module to adjust the speed at the current sampling moment.

[0102] The speed increment can be input into the adjustment module to directly adjust the speed. Since the road material damage after stratification may be relatively low overall, the speed needs to be increased to work efficiently, so the speed adjustment is incremental adjustment.

[0103] In the embodiment of the present invention, the sum of the speed adjustment amount at the current sampling moment and the speed at the previous sampling moment in the time sequence is used as the adjustment speed at the current sampling moment to achieve incremental adjustment. Considering the operating range of the speed, when the adjustment speed is less than or equal to the preset speed upper limit, the increment can be performed, and the speed at the current sampling moment is the adjustment speed. When the adjustment speed is greater than the preset speed upper limit, the increment exceeds the device setting, and the speed at the current sampling moment is the preset speed upper limit.

[0104] At this point, the adjusted speed result at the current sampling moment is obtained. In a possible implementation method of the embodiment of the present invention, when the speed reaches the preset speed upper limit, the subsequent increment cannot be continued. At this time, the adjustment module can directly stop adjusting and complete the subsequent coring process through the preset speed upper limit.

[0105] In an embodiment of the present invention, when the displacement of the coring reaches the sampling requirement, the rotation is stopped, the sampling barrel is tilted at a certain angle, and the push rod at the bottom of the sampling barrel is pushed by the hydraulic device to push the core sample in the sampling barrel, and the core sample is taken out of the sampling barrel for subsequent testing.

[0106] In summary, the present invention determines the initial rotation speed of coring by the initial compaction displacement, considers the softening layer of the road surface, avoids the core sample being broken due to the initial rotation speed being fast enough, and then determines the stratification moment by the change of the pressure value. In the process of accelerating and efficiently coring after passing the softening layer, further considers the possibility of the core sample being broken due to the influence of shear force due to the excessive acceleration. After the stratification moment, the distribution between the pressure value and the displacement before the current moment and the stratification moment is analyzed to obtain the road hardness change and the shear strength of the core sample connection. The speed adjustment and correction is considered from the changes in the hardness affected by different depths at the current moment and the possible degree of the influence of shear force on the stratified part, so as to further combine the pressure change and the speed situation at the previous moment to obtain the speed adjustment amount and adjust the speed more appropriately. The present invention considers the influence of the stratified part of the core sample during the initial speed selection and subsequent adjustment of the coring device, and adaptively adjusts the speed, so that the running coring speed can complete the work more efficiently while ensuring the quality of the core sample, thereby improving the quality of subsequent detection.

[0107] It should be noted that the sequence of the above embodiments of the present invention is only for description and does not represent the advantages and disadvantages of the embodiments. The processes depicted in the accompanying drawings do not necessarily require the specific order or continuous order shown to achieve the desired results. In some embodiments, multitasking and parallel processing are also possible or may be advantageous.

[0108] The various embodiments in this specification are described in a progressive manner, and the same or similar parts between the various embodiments can be referenced to each other, and each embodiment focuses on the differences from other embodiments.

Claims

1. A coring device for road construction quality inspection, the main body of which comprises a connecting tube and a sampling barrel, characterized in that: The main body also includes a speed regulating mechanism, which includes a data acquisition module, a speed regulation analysis module and a regulation module; The signal output end of the data acquisition module is connected to the signal input end of the speed regulation and analysis module, and the signal output end of the speed regulation and analysis module is connected to the signal input end of the regulation module; the regulation module is used to control the speed of the coring device; The data acquisition module is used to collect the pressure value during the coring process through the pressure sensor on the connecting tube, and collect the displacement and initial compaction displacement during the coring process through the encoder on the sampling barrel; the pressure value and displacement at each sampling moment during the coring process, as well as the initial compaction amount are transmitted to the speed regulation and analysis module; The speed adjustment and analysis module is used to determine the starting speed of the coring process according to the initial compaction displacement; During the coring process, the stratification moment is determined according to the significance of the pressure value change in the time series; After the delamination moment, the road hardness change degree at the current sampling moment is obtained according to the distribution difference between the pressure value change degree and displacement amount in the time series before the current sampling moment and the delamination moment; the core sample joint shear stress at the current sampling moment is obtained according to the proximity between the pressure value change degree and displacement amount at the current sampling moment and the delamination moment; After the stratification moment, according to the pressure value change at the current sampling moment, the sudden change of road hardness and the shear stress of the core sample connection, combined with the speed at the previous sampling moment in the time sequence, the speed adjustment value at the current sampling moment is obtained; The speed adjustment amount is input into the regulation module to adjust the speed at the current sampling moment.

2. A coring device for road construction quality inspection according to claim 1, characterized in that: The method for obtaining the road hardness variation degree includes: Before the current sampling moment, the variation deviation of each sampling moment is obtained according to the deviation degree of the pressure value and the proximity degree of the displacement between each sampling moment and the stratification moment; The road hardness variation at the current sampling moment is obtained by combining the variation deviations at all sampling moments before the current sampling moment.

3. A coring device for road construction quality inspection according to claim 2, characterized in that: The method for obtaining the change deviation comprises: For any sampling time before the current sampling time, the difference between the pressure value at the stratification time and the pressure value at the sampling time is taken as the pressure deviation at the sampling time; A negative correlation mapping is performed on the difference between the displacement at the sampling moment and the displacement at the stratification moment to obtain the distribution reliability at the sampling moment; The pressure deviation at the sampling moment is combined with the distribution confidence to obtain the variation deviation at the sampling moment.

4. A coring device for road construction quality inspection according to claim 1, characterized in that: The method for obtaining the core sample joint shear strength comprises: According to the difference between the pressure value change at the stratification moment and the current sampling moment, the mutation tolerance index at the current sampling moment is obtained; According to the proportion of the displacement at the delamination moment in the displacement at the current sampling moment, the distance tolerance index at the current sampling moment is obtained; The core sample connection shear stress at the current sampling moment is obtained by combining the mutation bearing index and the distance bearing index at the current sampling moment.

5. A coring device for road construction quality inspection according to claim 4, characterized in that: The method of obtaining the mutation tolerance index at the current sampling moment according to the difference between the pressure value change at the stratification moment and the current sampling moment includes: The difference between the pressure value at the stratification moment and the pressure value at the previous sampling moment in the time series is taken as the pressure mutation degree; The difference between the pressure value at the current sampling moment and the pressure value at the previous sampling moment in time series is taken as the degree of change at the current sampling moment; The difference between the change degree at the current sampling moment and the pressure mutation degree is negatively correlated and mapped as the mutation tolerance index at the current sampling moment.

6. A coring device for road construction quality inspection according to claim 1, characterized in that: The method for obtaining the speed adjustment amount includes: The product of the sudden change of road hardness at the current sampling moment and the shear stress of the core sample connection is negatively correlated and normalized to obtain the adjustment correction coefficient at the current sampling moment; According to the change degree between the pressure value at the current sampling moment and the pressure value at the previous sampling moment in the time series, combined with the speed at the previous sampling moment in the time series, the initial speed adjustment degree at the current sampling moment is obtained; The product of the initial speed adjustment degree at the current sampling moment and the adjustment correction coefficient is used as the speed adjustment amount at the current sampling moment.

7. A coring device for road construction quality inspection according to claim 6, characterized in that: The initial speed adjustment degree at the current sampling moment is obtained according to the change degree between the pressure value at the current sampling moment and the pressure value at the previous sampling moment in the time sequence, combined with the speed at the previous sampling moment in the time sequence, including: The difference between the pressure value at the current sampling moment and the pressure value at the previous sampling moment in time series, and the ratio of the pressure value at the previous sampling moment, are used as the adjustment coefficient at the current sampling moment; The product of the adjustment coefficient at the current sampling moment and the rotation speed at the previous sampling moment in time sequence is used as the initial rotation speed adjustment degree at the current sampling moment.

8. A coring device for road construction quality inspection according to claim 1, characterized in that: The inputting the speed adjustment amount into the regulating module to regulate the speed at the current sampling moment includes: The sum of the speed adjustment at the current sampling moment and the speed at the previous sampling moment in the time sequence is used as the adjustment speed at the current sampling moment; When the adjusted speed is less than or equal to the preset upper speed limit, the speed at the current sampling moment is the adjusted speed; when the adjusted speed is greater than the preset upper speed limit, the speed at the current sampling moment is the preset upper speed limit.

9. A coring device for road construction quality inspection according to claim 1, characterized in that: The method of determining the starting rotation speed of the coring process according to the initial compaction displacement comprises: When the initial compaction displacement is less than the preset initial maximum displacement, the ratio of the initial compaction displacement to the preset initial maximum displacement is used as the adjustment ratio; the difference between the preset upper speed limit and the preset lower speed limit is used as the adjustment range; The product of the adjustment ratio and the adjustment range is used as the initial adjustment amount; the difference between the preset upper speed limit and the initial adjustment amount is calculated as the starting speed of the coring process; When the initial compaction displacement is greater than or equal to the preset initial maximum displacement, the preset rotation speed lower limit is used as the rotation speed for starting the coring process.

10. A coring device for road construction quality inspection according to claim 1, characterized in that: In the coring process, determining the delamination time according to the significance of the pressure value change in the time series includes: The pressure value difference between each two adjacent sampling moments in the time sequence before the current sampling moment is taken as the pressure value change degree, and all the pressure value change degrees are sorted in time sequence to obtain the pressure value change sequence at the current sampling moment; The difference between the last two pressure value change degrees in the pressure value change sequence is used as the pressure change index at the current sampling moment; except for the last pressure value change degree in the pressure value change sequence, the difference between the change degrees of every two adjacent pressure values ​​in the pressure value change sequence is calculated and the maximum value of all the differences is used as the extreme value of change at the current moment; When the pressure change index at the current sampling moment is greater than the extreme value of the change, the current sampling moment is taken as the stratification moment.

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