21 results about "Falling weight deflectometer" patented technology

The invention relates to the technical field of data error correction, in particular to a calibration error correction method and system for a falling weight deflectometer, and the method comprises the steps: obtaining deflection values of a displacement sensor of the falling weight deflectometer to form a deflection program sequence, calculating deflection abnormal values of the deflection values, obtaining deflection rightward sequences of the deflection values, and calculating deflection error sequences of the deflection values; the method comprises the following steps: acquiring a deflection value of each deflection value, further acquiring a deflection continuation characteristic value of each deflection value, acquiring a load transfer weight of each deflection value through a correlation degree between local deflection sequences of deflection values of the same bit sequence in a program sequence during adjacent deflection, and acquiring a road looseness influence degree of each deflection value in combination with the deflection continuation characteristic value corresponding to each deflection value. Further acquiring deflection vibration characteristic values of the deflection values and smooth window scales of the deflection values, and smoothing the program columns during deflection so as to correct deflection data errors of the drop weight deflectometer. According to the application, the calibration error correction precision of the drop weight deflectometer can be improved.

The utility model discloses an unmanned deflection detection device which comprises a workbench support unit, a drop hammer type deflectometer is installed in the middle of the workbench support unit through bolts, and a road surface cleaning device is fixedly installed below the workbench support unit. According to the road surface cleaning device disclosed by the utility model, the heavy drop hammer type deflectometer can be moved to a specified detection point through the arranged moving assembly, and the pressing plate is supported on the road surface through the air cylinder after the heavy hammer type deflectometer is moved, so that the phenomenon that the device moves when a heavy hammer is used is prevented, and the detection accuracy can be further improved; in addition, the arranged sweeping assembly can move through the transmission assembly, then broken stones and dust appearing on the detection points can be swept away, dust removal is further conducted through air blown out by the air pump, and therefore the situation that road settlement deformation detection is hindered by the broken stones and the dust at the detection points is relieved, the road settlement deformation detection is even in stress, and the detection accuracy is improved.

The present invention relates to the technical field of road engineering, and provides a deflection basin parameter determination method and apparatus, a road testing device, a medium and a product. The method comprises: by means of a ground penetrating radar, acquiring a real-time deflection basin evaluation index value of any point in a road segment to be tested; and inputting the real-time deflection basin evaluation index value into a deflection basin parameter prediction model, to obtain a predicted deflection basin parameter value, wherein the deflection basin parameter prediction model is obtained by performing training on the basis of at least one deflection basin parameter value and a deflection basin evaluation index value which correspond to a reference point in a reference road segment, the at least one deflection basin parameter value is determined by means of a falling weight deflectometer, and the deflection basin evaluation index value is determined by the ground penetrating radar. In the present invention, a deflection basin parameter can be predicted simply by obtaining a real-time deflection basin evaluation index value by a ground penetrating radar, thereby improving the efficiency of deflection basin parameter determination.

The invention discloses a method for determining an initial modulus of a semi-rigid base of an in-service asphalt pavement, and relates to the technical field of road engineering, a preset monitoring point of the in-service asphalt pavement is detected through a drop weight deflectometer, and a base modulus value is obtained through back calculation based on a deflection detection result; based on the transverse distribution coefficient of the carriageway, respectively calculating the accumulated axle load action times of the preset monitoring points; establishing a basic layer modulus damage model with basic layer initial modulus parameters by utilizing the structure behavior equation; and detecting basic layer modulus values under different accumulated axle load action times by using a drop weight deflectometer, performing regression fitting to obtain model parameters, obtaining a complete basic layer modulus damage model, and obtaining a basic layer initial modulus. According to the method, the initial modulus of the base layer is determined through the drop weight deflectometer.

A drop hammer deflectometer for pavement detection belongs to the technical field of pavement detection equipment and comprises a guide rod, a bearing plate and a heavy hammer, the bearing plate is arranged at the bottom end of the guide rod, the heavy hammer is slidably sleeved on the guide rod, a positioning disc is mounted at the top end of the heavy hammer, and the area of the upper surface of the positioning disc is smaller than that of the lower surface of the positioning disc. Compared with a traditional single-point bearing mode, the counter weight bearing device can carry out circumferential equidistant multi-point bearing on the counter weight, can avoid relative inclination caused by single-point bearing of the counter weight on the guide rod, and avoids friction caused by the inclination angle generated by the counter weight and the guide rod, so that the service life of the counter weight is prolonged, and the service life of the counter weight is prolonged. The heavy hammer can normally and freely fall along the guide rod in the subsequent road surface detection link, the accuracy of the road surface detection result is ensured, in addition, the supporting blocks do not need to be driven one by one to rotate, the four groups of supporting blocks are linked at the same time, and locking positioning or locking positioning removal of the heavy hammer is quicker and more convenient.

The application relates to the technical field of data error correction, in particular to a calibration error correction method and system of a drop hammer type deflectometer, which comprises the following steps: obtaining deflection values of a displacement sensor of the drop hammer type deflectometer to form a deflection time sequence, calculating deflection abnormal values of each deflection value, obtaining each deflection right sequence of each deflection value, further obtaining deflection continuation characteristic values of each deflection value, obtaining load transfer weights of each deflection value through the correlation degree between local deflection sequences of the same bit sequence deflection value in adjacent deflection time sequences, obtaining road loose influence degrees of each deflection value in combination with the deflection continuation characteristic values of the corresponding deflection values, further obtaining deflection vibration characteristic values of each deflection value and smoothing window scales of each deflection value, and performing smoothing treatment on each deflection time sequence to correct deflection data errors of the drop hammer type deflectometer. The application can improve the calibration error correction precision of the drop hammer type deflectometer.

The invention relates to the technical field of road engineering, and discloses an old road composite disease layered repair and asphalt paving integrated process which comprises the following steps: carrying out layered targeted repair on old road diseases; carrying out synergistic enhancement treatment on a repair interface, namely arranging a high-elasticity polyurethane and asphalt stress absorption layer at a construction joint of the new and old plates, and carrying out mechanical micro grooving on the surface of a grouting area; evaluating a representative deflection value of the repaired pavement by using a drop weight deflectometer, and dynamically matching an asphalt paving structure scheme; after the glass fiber grating is laid, the matching scheme is executed. According to the composite pavement structure disclosed by the invention, a synergistic enhancement interface comprising the stress absorption layer and the micro-carving grooves is arranged between the repaired base layer and the asphalt surface layer. According to the method, the quantitative feedback relationship between the repairing effect and the paving design is established, and the systematicness and accuracy of the repairing project are improved by cooperatively enhancing the interface to inhibit the reflection crack.

This invention discloses a numerical simulation method for the maintenance and construction of semi-flexible pavement based on dual-scale coupling, comprising: determining the dimensions of the milled and repaved section based on the original pavement structure obtained by three-dimensional ground-penetrating radar and falling-weight deflectometer; establishing a finite element model for the original pavement structure; simulating the semi-flexible layer after milling and repaving using discrete element method and coupling it into the finite element model to construct a dual-scale coupled model; performing simulation calculations on the compaction and molding of large-void parent asphalt mixture; conducting simulation derivation of self-leveling cement slurry filling based on the construction process and the dual-scale coupled model; establishing a discrete element numerical model for cement curing to characterize cement curing behavior; and evaluating and guiding the maintenance of the semi-flexible pavement based on the dual-scale coupled model. This invention realizes process control and performance evaluation during the construction period of semi-flexible pavement and guidance for maintenance and repair during service life, making up for the shortcomings of high testing costs and insufficient theoretical data for different construction conditions in semi-flexible pavement.

This invention relates to the field of roadbed strength, specifically to a method for detecting the strength of highway roadbeds based on a semi-empirical modified curve. This invention records the pressure and displacement during impact using sensors on a falling weight deflectometer, calculates the vertical displacement of the road surface, selects a Beckman beam deflectometer and a test vehicle, installs the Beckman beam deflectometer between the two rear wheels of the test vehicle, corrects the test vehicle parameters, calculates the deflection value, corrects the diameter of the left and right tires of the test vehicle to 22.35 cm, and corrects the ground pressure of the left and right tires of the test vehicle to 0.75 MPa. The vertical displacement and deflection values ​​measured in steps (2) and (3) are recorded and compared with the national highway roadbed strength standard, thereby achieving rapid detection of roadbed strength without damaging the road structure. Furthermore, the test vehicle can be used to detect and evaluate the road smoothness of the selected road.

A system for evaluating the strength improvement of the roadbed through bamboo fiber reinforcement, consisting of: a) a material processing unit for producing a soil-bamboo fiber mixture, wherein the bamboo fibers are selected from the group consisting of Barak (Bambusa balcooa), Bari (Bambusa polymorpha), and Mritinga (Bambusa tulda), wherein the fibers have a length of 1.5 cm and a diameter of 2-3 mm and are incorporated at a rate of 3% of the dry weight of the soil; b) a compaction test facility configured to perform the Standard Proctor compaction test to determine the maximum dry density (MDD) and optimal moisture content (OMC); c) a load-bearing capacity test unit configured to perform CBR (California Bearing Ratio) tests, wherein the test unit is designed for CBR tests in both the impregnated and unimpregnated states; d) a subgrade preparation unit configured to prepare a subgrade test section for roadways, comprising layering and compacting the soil-bamboo fiber mixture in 150 mm thick layers to achieve a subgrade thickness of approximately 600 mm; and e) a deflection measuring unit for performing a falling weight deflectometer (FWD) test, wherein the deflection measuring unit comprises seven geophone sensors arranged at intervals of 0 mm, 300 mm, 600 mm, 900 mm, 1200 mm, 1500 mm and 1800 mm from the center of a load plate, and a load cell configured to apply a load of 40 kN.

The application relates to a pavement nondestructive detection device and method based on a ground penetrating radar and a deflectometer, and belongs to the technical field of pavement nondestructive detection. The detection device comprises a mobile base, a ground penetrating radar for acquiring pavement detection data, a drop hammer deflectometer for acquiring a deflection basin index at a pavement disease position, and a marking structure for marking the pavement disease position. One pavement disease type corresponds to one mark. A controller comprises an information receiving module for receiving the detection data and the deflection basin index, a judgment module for determining the pavement disease position and the corresponding pavement disease type and determining the pavement disease degree, a position acquiring module for acquiring the current position of the drop hammer deflectometer in real time, and a control module for controlling the drop hammer deflectometer to act when the current position matches the pavement disease position and for controlling the marking structure to act after the pavement disease position is determined. The application has the beneficial effect of reducing the core drilling verification step.

The invention belongs to the crossing field of road engineering technology and artificial intelligence, and particularly relates to a road structure modulus back calculation method based on a large model and reinforcement learning. Analyzing and extracting structured parameters by a large language model, and generating initial modulus estimation driven by engineering knowledge; constructing a forward mechanical model based on a two-dimensional axisymmetric finite element, and calculating a theoretical deflection basin; designing a composite reward function, and driving a reinforcement learning agent to iteratively adjust the modulus of each structural layer; and in the optimization process, a large language model is periodically called to provide optimization direction guidance, and local optimum is prevented. Compared with a traditional back calculation method, the method has the advantages that the convergence rate is 100% on a synthetic data set, and the average deflection error is 1.69 + / -0.69%; the method supports adaptive processing of various road surface types such as flexible road surfaces, semi-rigid base layers and atypical structures, and has high robustness and engineering practicability.

The invention provides a road underground cavity detection method and device based on a drop weight deflectometer, and relates to the technical field of underground engineering. The method comprises the following steps: acquiring a first deflection data set acquired by each displacement sensor when each stage of hammering load is applied; and under the same-level hammering load, a second deflection data set corresponding to each second displacement sensor is obtained according to the first deflection data set collected by the first displacement sensor and the first deflection data set collected by each second displacement sensor. Inputting the thickness of the road structure layer, the road type, a plurality of first deflection data sets collected by the first displacement sensor under the multi-stage hammering load and a plurality of second deflection data sets corresponding to each second displacement sensor under the multi-stage hammering load into a cavity prediction model, and obtaining a first judgment result output by the cavity prediction model. And determining whether there is a hole in the test point according to the first determination result, thereby improving the accuracy of road underground hole detection.

This utility model relates to the technical field of vehicle-mounted falling weight deflectometers and discloses a vehicle-mounted falling weight deflectometer, including a support frame. An automatic detection and cleaning mechanism is provided on the outer side of the support frame. The automatic detection and cleaning mechanism includes a movable storage platform. Two hydraulic cylinders are fixedly connected to the outer surface of the support frame, and the extension end of each hydraulic cylinder is fixedly connected to the outer surface of the movable storage platform. The outer surface of the movable storage platform is slidably connected to the interior of the support frame. This vehicle-mounted falling weight deflectometer, by incorporating the automatic detection and cleaning mechanism, can automatically detect and clean impurities on the outer surface of the falling weight. Simultaneously, it can precisely adjust the height and overall weight of the falling weight according to experimental requirements, not only improving the applicability of the device but also enhancing the accuracy of the experiments. It effectively prevents impurities from adhering to the surface of the falling weight, affecting the depth of subsequent falling weight experiments, and thus reducing the effectiveness of the device.

The application provides a road deflection detection device with active anti-collision protection, and belongs to the technical field of road detection. The road deflection detection device with active anti-collision protection comprises a handheld falling weight deflectometer, an anti-collision mechanism for preventing the force receiving structure from being impacted by the falling object is arranged above the bearing plate, and a protection mechanism is arranged above the bearing plate. Before the falling weight is about to fall, the distance between the two groups of threaded seats is increased by controlling the motor, the threaded seat movement drives the movement of the two groups of protection plates, the falling weight can pass between the two groups of protection plates, contact the force receiving structure, and when the falling weight does not need to fall, the two groups of protection plates can prevent the remaining falling objects from contacting the force receiving structure, thereby solving the problem that when the force receiving structure is not impacted by the falling weight, the upper part of the force receiving structure may be contacted by the falling object, the falling object generates a certain impact force, and the subsequent numerical analysis may be affected.

The evaluation method for the grouting reinforcement effect of the cement concrete pavement of the present application comprises: before grouting: S1.1, setting multiple test points in the evaluation section; S1.2, collecting deflection basin data of each test point by using a falling weight deflectometer; S1.3, calculating the comprehensive equivalent resilient modulus E of the test points before grouting Fi ; S1.4, correcting the comprehensive equivalent resilient modulus E Fi , to obtain a corrected value E F . After grouting: S2.1, collecting deflection basin data of each test point by using a falling weight deflectometer; S2.2, calculating the comprehensive equivalent resilient modulus E of the test points after grouting Bi ; S2.3, correcting the comprehensive equivalent resilient modulus E Bi , to obtain a corrected value E B . Evaluation: S3, outputting the evaluation result of the grouting reinforcement effect according to the corrected values E F and E B . The evaluation method of the present application can effectively improve the accuracy of the evaluation result.

The utility model discloses a vehicle-mounted drop hammer type deflectometer, which relates to the technical field of traffic transportation engineering, and comprises a carrier loader, the outer walls of the two sides of the carrier loader are provided with grooves, the inner sides of the grooves are provided with connecting plates, one end part of each connecting plate is fixedly connected with an indication board, the front surface of the indication board is provided with a strobe light, and the strobe light is connected with the inner side of each groove. A groove is formed in one side of the carrier loader, a first rotating motor is fixedly mounted on one side of the groove, a first spur gear is fixedly connected to the output end of the first rotating motor, a drop weight deflectometer is fixedly mounted in the carrier loader, and a sensor frame is fixedly mounted on one side of the bottom end of the drop weight deflectometer. By arranging a series of structures, the cleaning frequency of the sensor at the bottom of the vehicle is reduced, meanwhile, the sensor can be easily cleaned, and therefore the adverse effect of muddy water on the detection result of the sensor is reduced, and the probability that other vehicles collide with the vehicle when the vehicle is parked for detection is reduced.

The invention relates to the technical field of road engineering nondestructive testing and state evaluation, in particular to a three-dimensional GPR-FWD integrated rapid diagnosis method and system for concealed diseases of a frozen soil road. The method comprises the following steps: synchronously acquiring pavement-base course-roadbed body data and a multi-base-distance deflection sequence of a road to be measured; an electromagnetic forward modeling library is called to generate a three-dimensional slice template, template matching is carried out, and disease categories, geometric scale parameters of diseases and similarity scores are output; carrying out power inversion of the drop weight deflectometer, and outputting the layer thickness and the equivalent modulus; performing calculation based on the multi-base-distance deflection sequence, and outputting a plurality of condition indexes; performing composite end point grading, and outputting disease grades and corresponding treatment suggestions; and generating a diagnosis report. The GPR map interpretation ambiguity is reduced, the layered modulus inversion accuracy is improved, a diagnosis-grading-disposal engineering closed loop is realized, the hidden disease discovery and disposal efficiency and accuracy can be remarkably improved, and the method has wide industrial application value.

The invention relates to the technical field of bearing performance evaluation, and particularly discloses a large-gap asphalt mixture pavement bearing performance evaluation and acceptance inspection method which comprises the following steps: S1, temporarily forming a flat interface transition layer on the surface of a pavement to eliminate the influence of surface gaps; s2, carrying out a loading test on the interface through a drop weight deflectometer, recording load and displacement data, generating a first deformation curve, and calculating a theoretical bearing capacity according to the first deformation curve; s3, the same loading test is carried out on the surfaces of the adjacent original large gaps, a second deformation curve is generated, and the actual bearing capacity is obtained; s4, calculating the ratio of the theoretical bearing capacity to the actual bearing capacity, and comparing the ratio with a preset threshold value to judge whether the bearing capacity of the road surface is qualified or not; according to the method, by comparing the test results of the ideal state and the actual state, quantitative evaluation of load transmission efficiency reduction caused by gaps of the large-gap pavement is realized.

The utility model relates to a collapsible loess roadbed compactness nondestructive testing device which comprises a supporting block, four air cavities are formed in the supporting block, a first through hole is formed in the lower end face of each air cavity, a first piston rod is arranged in each first through hole, and the lower end of each first piston rod is connected with a bearing plate through a ball corner. Four second through holes evenly distributed along the circumference are formed in the periphery of each first through hole, a second piston rod is arranged in each second through hole, a disc is arranged on the lower end face of each air cavity, a vertical hole is formed in the middle of each disc, and eight vertical holes penetrating through the upper end face and the lower end face are formed in each disc; according to the drop hammer deflectometer, a bearing plate of an existing drop hammer deflectometer is improved, so that after the bearing plate hammers the ground for the first time, all the second piston rods can downwards extend out and abut against the bearing plate under the action of air pressure, the supporting strength of the bearing plate is greatly improved, the stress of the universal joint structure is reduced, and the service life of the universal joint structure is prolonged.

The application provides a laser deflection instrument measurement result correction method based on a finite element model, and belongs to the technical field of measurement instrument measurement result correction, which comprises the following steps: constructing a viscoelastic pavement model; calculating a deflection parameter measurement value Y of the laser deflection instrument on the viscoelastic pavement model; calculating a standard deflection parameter measurement value Y0 of a falling weight deflectometer on the viscoelastic pavement model; calculating deflection correction parameters ρ under the action of various environmental factors through the deflection parameter measurement value Y and the standard deflection parameter measurement value Y0; screening out m environmental condition influence factors which have a greater influence on the measurement result of the laser deflection instrument; establishing a laser deflection instrument measurement result correction model; and correcting the measurement result of the laser deflection instrument according to the laser deflection instrument measurement result correction model. The measurement result of the laser deflection instrument is corrected, the accuracy of the measurement result of the laser deflection instrument is improved, and it is ensured that the measurement result does not affect the accuracy of subsequent modulus back calculation.