Road surface compressive strength measuring device

Abstract

The invention relates to the technical field of pavement testing, in particular to a pavement compressive strength measuring device which comprises a detection rack and a pressing detection assembly. The detection rack is provided with a hoisting cross beam, a pressing driving cavity and a sample bearing cavity, and the hydraulic jacking device drives the pressing working seat to stably move through the supporting guide rod. The press-fit detection assembly comprises a detection base, a press-fit detection substrate and a secondary detection assembly, the hoisting base frame and the displacement sensing frame are integrated with the pushing assembly to drive the press-fit detection substrate to generate displacement, and the detection system obtains surface fluctuation data in real time. And then, the secondary detection assembly performs contact measurement on the pressed area of the sample to obtain lateral contour data. The device comprehensively evaluates the compressive strength of the pavement material through multi-dimensional detection, improves the detection efficiency and accuracy, and provides powerful support for research and development and quality acceptance of road engineering materials.

Description

Technical Field

[0001] The invention relates to the technical field of road surface testing, in particular to a road surface compressive strength measuring device. Background Art

[0002] In the field of road construction and maintenance, the compressive strength of pavement materials is a key indicator for assessing their quality and service life, directly related to the road's bearing capacity and driving safety. The compressive strength measuring device consists of a high-strength base, supporting columns, and a crossbeam. The pressure unit uses a hydraulic jack with a pressure regulator to precisely apply force as needed. The pressure head is specially treated to ensure uniform pressure transmission. However, with the continuous growth of modern traffic volume and the increasing load of heavy vehicles, pavement structures face a more complex stress environment, placing higher demands on the accuracy and comprehensiveness of pavement compressive strength measurements.

[0003] Traditional pavement compressive strength measurement devices typically use a single vertical pressure application method, capturing only the vertical compressive strength of the pavement material. This measurement method has significant limitations and cannot fully capture the complex deformation characteristics of the pavement during compression, such as lateral deformation, sag, or tilt. This leads to deviations between the measured results and the actual stress state. This makes it difficult to effectively assess the performance of pavement materials under multi-directional stresses, and therefore fails to provide reliable data support for road design, construction quality control, and subsequent maintenance. Summary of the Invention

[0004] The purpose of the present invention is to provide a pavement compressive strength measuring device to solve the problems raised in the above background technology.

[0005] To achieve the above object, the present invention provides the following technical solutions:

[0006] A pavement compressive strength measuring device includes a detection frame and a compression detection assembly; the detection frame is topped with a hoisting crossbeam, and a downward pressure drive chamber and a sample holding chamber are formed within the frame, wherein the downward pressure drive chamber is located in the upper space, and the sample holding chamber is located in the lower space and is configured to position a pavement material sample;

[0007] A hydraulic jacking device is installed at the center line of the hoisting beam, and a plurality of supporting guide rods are symmetrically arranged along its side; the driving end of the hydraulic jacking device is connected to a pressing work seat, which forms a sliding limit connection with the hoisting beam through the supporting guide rods; the pressing detection assembly is fixedly installed on the bottom surface of the pressing work seat;

[0008] The press-fit detection assembly includes a detection base, the bottom surface of which is configured with:

[0009] Press-fit detection substrate, serving as the main pressure-applying component of the detection base;

[0010] The secondary detection component is suspended on the edge area of ​​the detection base through the secondary detection hanger;

[0011] The bottom surface of the detection base is also integrated with:

[0012] Hoist the base frame to form the main structural support;

[0013] The displacement sensing frame is nested inside the hoisting base frame and is equipped with a push assembly;

[0014] The pressing detection substrate forms a mechanical connection with the driving end of the pushing assembly;

[0015] When the compression test substrate applies pressure to the pavement sample, the displacement sensing frame monitors the displacement change during the pressure application process in real time; the compression test substrate is driven by the push component to produce a preset displacement, and the detection system obtains the surface fluctuation data of the pavement after being compressed; then the secondary detection component performs a descending action and performs contact measurement of the lateral profile of the compressed area of ​​the sample to obtain possible depression or tilt deformation parameters of the pavement.

[0016] As a further solution of the present invention: the lifting base frame is fixedly connected to the bottom plate surface of the detection base, and the top of the detection base is rigidly installed on the bottom surface of the pressing work seat through a positioning fixing block; the plate body of the detection base is rigidly connected to the secondary detection hanger through a lateral lifting connector; the bottom side edge of the lifting base frame is rigidly equipped with a fixed side plate, and the inner plate surface of the fixed side plate is provided with a plurality of displacement guide rails along the vertical direction.

[0017] As a further solution of the present invention: the displacement sensing frame includes a supporting base plate, and the side edges of the supporting base plate are equipped with displacement sliders at positions corresponding to the displacement guide rails; each displacement slider forms a sliding interlocking connection with the corresponding displacement guide rail through a lateral support block, so that the displacement sensing frame and the lifting base frame constitute a vertical guiding mechanism; the lateral end face of the displacement slider is provided with a displacement measurement sensor.

[0018] As a further solution of the present invention: the displacement measurement sensor includes an elastic top pressure rod and a pressure sensing unit; the bottom end of the elastic top pressure rod is fixedly connected to the upper surface of the supporting base plate, and the top end thereof passes through the displacement slider and extends to the inner surface of the top frame of the lifting base frame; the pressure sensing unit is embedded in the top end of the elastic top pressure rod and maintains elastic contact with the inner surface of the top frame of the lifting base frame, forming a dynamic measurement mechanism of pressure displacement.

[0019] As a further solution of the present invention: the pushing assembly includes a fixed end seat and a pushing drive module, the fixed end seat is rigidly connected to the two ends of the supporting base plate, and the pushing drive module is mounted between the two fixed end seats; a precision transmission screw is rotatably arranged between the two fixed end seats, and a pushing base is slidably arranged on the pushing drive module, and the pushing base forms a spiral transmission connection with the precision transmission screw; the bottom of the precision transmission screw is fixedly connected to a lifting fixed seat, and the plate body of the supporting base plate is provided with a sliding groove in the horizontal direction, and the lifting fixed seat is slidably embedded in the sliding groove; the top of the pressing detection substrate is rigidly connected to the bottom surface of the lifting fixed seat through the mounting disc body.

[0020] As a further solution of the present invention: the pressing detection substrate includes a substrate body, the bottom surface of the substrate body is provided with a plurality of detection through holes, the substrate body is a hollow cavity structure, and the inner cavity thereof is horizontally provided with an intra-cavity transverse support bar; the upper surface of the intra-cavity transverse support bar is fixedly equipped with a plurality of fixing clips, and the inner cavity of the substrate body is vertically penetrated by a plurality of detection tubes, each detection tube is rigidly fixed to the upper surface of the intra-cavity transverse support bar by a fixing clip; the bottom end of each detection tube is equipped with a single-point sensor, the single-point sensor is configured in a one-to-one correspondence with the detection through hole, and the sensor detection end extends into the axial channel of the detection through hole.

[0021] As a further solution of the present invention: a gap is formed between the detection tubes in the middle area, and an azimuth angle sensor is arranged in the gap. The azimuth angle sensor is rigidly mounted on the inner cavity wall of the substrate body and is distributed in an array around the detection tubes in this area.

[0022] As a further solution of the present invention: the secondary detection component includes a lateral adjustment frame, a sliding mounting plate and a lateral depression detection sensor; the lateral adjustment frame is rigidly hoisted at the bottom end of the secondary detection hanger, and a lateral slide rail and a lateral drive push rod are arranged inside it; the sliding mounting plate forms a horizontal sliding connection with the lateral adjustment frame through the lateral slide rail, and realizes horizontal displacement drive through the lateral drive push rod; the bottom surface of the sliding mounting plate is vertically equipped with a lifting adjustment screw, and the lateral depression detection sensor is rigidly connected to the bottom end of the lifting adjustment screw.

[0023] As a further solution of the present invention: the main body of the lateral depression detection sensor is a T-shaped detection bracket, and a fixed reference detection probe is rigidly assembled on one side of the vertical section of the T-shaped detection bracket, and the surface of the horizontal section is slidably connected to a movable probe mounting plate through a first-level fine-tuning base; the first-level fine-tuning base includes a guide rail and a fine-tuning knob, so that the movable probe mounting plate can be displaced and adjusted along the horizontal axis of the T-shaped detection bracket; a secondary driving cylinder is vertically fixed to the surface of the movable probe mounting plate, and the driving end of the secondary driving cylinder is rigidly connected to the movable reference detection probe.

[0024] As a further solution of the present invention: the detection end faces of the fixed reference detection probe and the bottom of the movable reference detection probe are kept in a coplanar configuration. When the secondary driving cylinder drives the movable reference detection probe to extend, its detection end face and the detection end face of the fixed reference detection probe form a parallel detection surface with an adjustable vertical spacing.

[0025] Compared with the prior art, the present invention has the following beneficial effects:

[0026] The present invention consists of a testing frame, a compression testing assembly, a displacement sensing frame, a push assembly, a compression testing substrate, and a secondary testing assembly. These components work together to achieve comprehensive, high-precision testing of the compressive strength of pavement materials. It can simultaneously acquire pressure-displacement curves, surface topography data, and lateral profile parameters, enabling a comprehensive assessment of the mechanical properties of pavement materials.

[0027] By coupling a high-precision displacement drive with a multi-dimensional sensor array, the system enables refined detection of pavement compressive wrinkle deformation. A dual-probe parallel detection system eliminates surface roughness interference through differential measurement, enabling micron-level dent detection. This device significantly enhances the scientific and reliable nature of pavement material testing, increasing detection efficiency by 40% compared to traditional solutions. The surface topography measurement error is ≤0.5μm, enabling high-precision, multi-dimensional, and efficient testing of pavement material mechanical properties.

[0028] It should be understood that the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] The accompanying drawings are incorporated into and constitute a part of the specification to illustrate embodiments consistent with the present application and, together with the specification, serve to explain the principles of the present application. These drawings and the accompanying description are not intended to limit the scope of the present application in any way, but rather to illustrate the concepts of the present application to those skilled in the art by reference to specific embodiments.

[0030] Figure 1 This is a schematic diagram of the overall structure of a pavement compressive strength measuring device provided by an embodiment of the present invention.

[0031] Figure 2 A schematic structural diagram of a press-fit detection assembly provided in an embodiment of the present invention.

[0032] Figure 3 A schematic diagram of the installation of the pressing detection substrate provided in an embodiment of the present invention relative to the detection base.

[0033] Figure 4 A schematic structural diagram of a displacement sensing frame and a push assembly provided in an embodiment of the present invention.

[0034] Figure 5 A structural perspective view of a press-fit detection substrate provided in an embodiment of the present invention.

[0035] Figure 6 A schematic structural diagram of a secondary detection component provided in an embodiment of the present invention.

[0036] Figure 7 This is a structural schematic diagram of a lateral depression detection sensor provided in an embodiment of the present invention.

[0037] In the figure: 1. Detection frame; 11. Lifting beam; 12. Downward pressure drive chamber; 13. Sample holding chamber; 14. Support guide rod; 15. Hydraulic jacking device; 16. Pressing work seat; 2. Pressing detection assembly; 3. Detection base seat; 31. Positioning fixed block; 32. Lateral lifting connector; 4. Secondary detection hanger; 5. Pressing detection substrate; 51. Substrate body; 52. Detection through hole; 53. Detection guide tube; 54. Single point sensor; 56. Azimuth angle sensor; 57. Mounting plate; 58. Intracavity transverse support bar; 59. Fixing buckle; 6. Secondary detection assembly; 61. Transverse adjustment frame; 62. Sliding mounting plate; 63. Transverse slide rail; 64. Transverse drive push rod Rod; 65. Lateral depression detection sensor; 66. Lifting adjustment screw; 651. T-type detection bracket; 652. Movable probe mounting plate; 653. Secondary drive cylinder; 654. Movable reference detection probe; 655. Primary fine-tuning base; 656. Fixed reference detection probe; 7. Lifting base frame; 71. Fixed side plate; 72. Displacement guide rail; 8. Displacement sensing frame; 81. Support base plate; 82. Displacement slider; 83. Lateral support block; 84. Displacement measurement sensor; 85. Elastic top pressure rod; 86. Pressure sensing unit; 9. Push assembly; 91. Fixed end seat; 92. Precision transmission screw; 93. Push drive module; 94. Push base; 95. Lifting fixed seat. DETAILED DESCRIPTION

[0038] The following will be combined with the accompanying drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention, and examples thereof are shown in the accompanying drawings. When the following description refers to the drawings, unless otherwise indicated, the same numbers in different drawings represent the same or similar elements.

[0039] Obviously, the embodiments described are only some of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0040] The specific implementation of the present invention is described in detail below with reference to specific embodiments.

[0041] For example 1, please refer to Figures 1 to 3 , provides a pavement compressive strength measuring device, which is suitable for the mechanical property evaluation of pavement materials such as asphalt concrete and cement concrete, and consists of a detection frame 1, a pressing detection component 2 and a supporting detection system; the main body of the detection frame 1 adopts a high-strength alloy steel welded frame, with a hoisting beam 11 configured on the top, and the interior is divided into a downward pressure driving chamber 12 and a sample holding chamber 13 by a partition. The downward pressure driving chamber 12 has a built-in hydraulic jacking device 15, the driving end of which passes through the center line of the hoisting beam 11, and the output end is connected to the pressing work seat 16. The bottom of the sample holding chamber 13 is equipped with a sample positioning tool, and the pavement material sample is fixed by bolts. The support guide rods 14 are symmetrically arranged on both sides of the hydraulic jacking device 15, forming a high-precision sliding limit with the pressing work seat 16 to ensure that the verticality of the downward pressure process is ≤0.02mm.

[0042] The pressing detection assembly 2 is fixed to the bottom surface of the pressing work seat 16, and includes a detection base seat 3 and an integrated detection module: the detection base seat 3 is the core bearing component, and the bottom surface integrates the following structures:

[0043] The press-fit detection substrate 5 is made of a quenched alloy with a surface roughness of Ra ≤ 0.4μm. It serves as a direct pressure-applying component in contact with the sample. The secondary detection assembly 6 is suspended from the edge of the detection base 3 via the secondary detection hanger 4 and contains a built-in high-precision displacement sensor array. The hoisting base frame 7 provides rigid support while reducing its own weight. The displacement sensing frame 8 is nested within the hoisting base frame 7 and contains a built-in electric push assembly 9, which can drive the press-fit detection substrate 5 to achieve 0.01mm micro-displacement.

[0044] During operation, a pavement material sample (size φ150×100mm) is placed on the positioning stage of the sample holding chamber 13. The laser alignment system is used to align the sample center with the axis of the pressing test substrate 5. During the initial pressurization phase, the hydraulic jacking device 15 drives the pressing workbench 16 downward along the support guide rod 14. The pressing test substrate 5 is loaded to a preset pressure value (e.g., 100kN) at a rate of 5kN / s. The displacement sensing frame 8 simultaneously records the initial indentation depth. Dynamic displacement testing is then performed. The push assembly 9 drives the pressing test substrate 5 to generate periodic sinusoidal displacement (amplitude 0.5mm, frequency 2Hz). The detection system collects pavement surface fluctuation data and generates a dynamic modulus-displacement curve. Lateral deformation testing is then performed. The secondary detection assembly 6 descends via an electric screw mechanism. Its contact contacts the sample sidewall with a preload of 0.1N. It scans the edge of the pressurized area along a preset trajectory to obtain radial depression and tilt angle data. Finally, the data is output and the host computer software automatically generates a compressive strength report, including the compressive strength value, elastic modulus, Poisson's ratio and three-dimensional deformation cloud map.

[0045] In this embodiment, the hydraulic jacking device 15 realizes large-tonnage loading, and the displacement sensing frame 8 adopts an inductive displacement sensor to convert mechanical displacement into an electrical signal with an accuracy of ±0.005mm. The static loading of the pressing detection substrate 5 is combined with the dynamic displacement test to simulate the actual road load condition; the contact scanning of the secondary detection component 6 can capture micron-level lateral deformation, breaking through the limitations of traditional single pressure-displacement detection. The integrated pressure-displacement-deformation three-parameter detection can distinguish between the elastic deformation and plastic damage stages of the material. Through the collaborative design of the mechanical-hydraulic-sensing system, this embodiment realizes high-precision, multi-dimensional detection of the compressive properties of pavement materials, providing key data support for road engineering quality control.

[0046] Example 2: This example is based on Example 1. Figure 2 、 Figure 3 and Figure 4 , the displacement sensing frame 8 and related components are optimized and designed, and the specific structure is as follows:

[0047] The top of the detection base seat 3 is rigidly fixed to the bottom surface of the pressing work seat 16 through a positioning fixing block 31, and is rigidly connected to the secondary detection hanger 4 through a lateral lifting connector 32 to ensure the overall rigidity of the detection assembly.

[0048] The hoisting base frame 7 is made of high-strength aluminum alloy, and the bottom side edge is rigidly assembled with a fixed side plate 71. The inner plate surface is precisely machined along the vertical direction with multiple displacement guide rails 72 (spacing 10mm, surface roughness Ra≤0.2μm) as the guide reference for the displacement sensing frame 8.

[0049] For the displacement sensing frame 8, the supporting base plate 81 serves as the main body of the frame, and high-precision displacement sliders 82 are installed on the side edges corresponding to the displacement guide rails 72. Each slider is slidably engaged with the displacement guide rails 72 through lateral support blocks 83 to form a vertical guiding mechanism with a repeatability accuracy of ≤0.003mm.

[0050] The displacement measurement sensor 84 includes an elastic pressure rod 85 and a pressure sensing unit 86. The bottom end of the elastic pressure rod 85 is fixed to the upper surface of the supporting base plate 81, and the top end passes through the displacement slider 82 and extends to the inner surface of the top frame of the lifting base frame 7. It is made of spring steel, and the axial stiffness is optimized to be 120N / mm.

[0051] The pressure sensing unit 86 is embedded in the top of the elastic top pressure rod 85, and has a built-in semiconductor strain gauge, which maintains elastic contact with the inner surface of the top frame of the lifting base frame 7 to form a dynamic measurement mechanism with a resolution of 0.001mm.

[0052] During operation, the hydraulic lifting device 15 is activated to raise the pressing workbench 16 to a safe height. The displacement sensing frame 8 naturally droops under the influence of gravity, and the pressure sensing unit 86 at the top of the elastic push rod 85 contacts the top frame of the lifting base frame 7, recording the initial pressure value F0. During the specimen loading phase, the pressing test base 5 loads the pavement specimen at a set rate (e.g., 10 kN / s). The displacement sensing frame 8 moves downward synchronously with the pressing workbench 16, and the displacement slide 82 slides along the displacement guide rail 72. The pressure sensing unit 86 monitors the compression ΔL of the elastic push rod 85 in real time, converting it into displacement using the formula σ = ΔL·k (k is the elastic push rod stiffness). The detection system simultaneously records the pressure-displacement curve and dynamic response data.

[0053] This embodiment utilizes the linear relationship between the axial deformation of the elastic push rod 85 and the pressure sensing unit 86 to convert mechanical displacement into an electrical signal output, thus avoiding the vulnerability of traditional grating scales to oil and contaminant interference. The displacement guide rail 72 and displacement slider 82 form the primary guidance system, while the lateral support block 83 provides auxiliary support, forming a dual-redundant guidance structure that effectively suppresses the impact of lateral runout on measurement accuracy.

[0054] Example 3: This example is a further optimization of Example 2. Figure 4 and Figure 5 , focusing on improving the coordinated detection mechanism of the push component 9 and the pressure detection substrate 5, and realizing the refined detection of the compressive wrinkle deformation of the road surface through the coupling design of high-precision displacement drive and multi-dimensional sensor array.

[0055] In the push assembly 9, the fixed end seat 91 is rigidly connected to the two ends of the support base plate 81, and a high-precision angular contact bearing is embedded inside to provide rotational support for the precision transmission screw 92. The precision transmission screw 92 adopts a C3 grade ground screw with a pitch of 2mm and a hard chrome-plated surface. Both ends are positioned by the fixed end seat 91, and the bottom is rigidly connected to the hoisting fixed seat 95. The push drive module 93 includes a servo motor and a reducer to drive the precision transmission screw 92 to rotate, and the driving torque is monitored in real time by a torque sensor. The push base 94 forms a spiral transmission connection with the precision transmission screw 92, and has a built-in circulating ball retainer to achieve low friction and high rigidity displacement output. The hoisting fixed seat 95 is slidably embedded in the horizontal sliding groove of the support base plate 81, and the bottom is rigidly connected to the pressing detection substrate 5 through the mounting disc 57.

[0056] The press-fit detection substrate 5 is comprised of a substrate body 51, constructed from titanium alloy. Its hollow cavity reduces its weight, and several 6mm diameter detection holes 52 are located at its base. Horizontal support bars 58 are welded horizontally to the inner cavity of the substrate body 51, with positioning grooves machined into the surface. These support bars 58 are used to rigidly secure the detection conduits 53. The detection conduits 53 are constructed from carbon fiber tubing, each equipped with a single-point sensor 54 (0-5mm range, 0.1μm resolution) at its base. The sensor's detection end extends to the axis of the detection hole 52. An azimuth angle sensor 56, distributed in a 2×2 or 3×3 array across the central area of ​​the detection conduit 53, features a built-in gyroscope to monitor the minute tilt angle of the substrate body 51 (resolution 0.001°).

[0057] During operation, the push drive module 93 rotates the precision transmission screw 92, which, through the push base 94, generates a slight horizontal vibration (amplitude 0.1 mm, frequency 10 Hz) on the press-fit detection substrate 5. The single-point sensor 54 captures road surface fluctuations in real time, and the azimuth angle sensor 56 monitors changes in the substrate's posture. When the pressure reaches its peak, the push assembly 9 drives the press-fit detection substrate 5 to perform a horizontal scan along a preset path (e.g., a serpentine trajectory). The single-point sensor 54 collects surface topography data of the compressed area and identifies the location and magnitude of wrinkle deformation by comparing it to a reference surface map. The detection system integrates pressure-displacement data, surface topography data, and azimuth angle data to reconstruct the road surface's three-dimensional deformation field using the finite element method, automatically marking wrinkle deformation areas and calculating deformation energy density.

[0058] This embodiment uses wavelet transforms to extract high-frequency deformation components based on dynamic surface topography data. Phase correlation analysis with a reference surface map is then used to automatically identify and quantify wrinkle deformation. Data collected by a multi-sensor array can be used to generate pavement deformation thermograms, visually displaying wrinkle distribution and providing a visual basis for optimizing material formulations. This approach is suitable for the development and quality inspection of high-performance pavement materials.

[0059] Example 4: This example is a further optimization of the above example. Figure 2 、 Figure 6 and Figure 7 On this basis, an innovative design is made for the detection mechanism of the secondary detection component 6 to realize the measurement of the lateral deformation of the road surface.

[0060] The secondary detection assembly 6 comprises a transverse adjustment frame 61, a sliding mounting plate 62, and a lateral sag detection sensor 65. Rigidly mounted to the bottom of the secondary detection hanger 4, the transverse adjustment frame 61 is welded from high-rigidity aluminum alloy profiles. Internally, it houses a transverse slide 63 and an electric transverse drive push rod 64, which drives the sliding mounting plate 62 for horizontal movement. The sliding mounting plate 62 is slidably connected to the transverse slide 63 via linear bearings. A vertically mounted lift adjustment screw 66, with an adjustment range of 0-50 mm, is used to vertically center the lateral sag detection sensor 65.

[0061] The lateral depression detection sensor 65 is a measurement implementation tool. The main body of the lateral depression detection sensor 65 is a T-shaped detection bracket 651. The T-shaped detection bracket 651 is made of Invar alloy. A fixed reference detection probe 656 is rigidly installed on the side of the vertical section, and a precision guide rail is processed on the surface of the horizontal section. Among them, the first-level fine-tuning base 655 includes a wedge-shaped slider mechanism driven by a differential head to achieve submicron displacement adjustment of the movable probe mounting plate 652. The second-level driving cylinder 653 has a built-in magnetostrictive displacement sensor, which drives the movable reference detection probe 654 to extend in a step of 0.01mm, forming a parallel detection surface with adjustable spacing with the fixed reference detection probe 656. The detection probe is equipped with a fixed reference detection probe 656 and a movable reference detection probe 654. Both the fixed reference detection probe 656 and the movable reference detection probe 654 use inductive displacement sensors.

[0062] During operation, the lateral driving push rod 64 drives the sliding mounting plate 62 to move above the lateral detection area of ​​the sample, and the lifting adjustment screw 66 fine-tunes the sensor height so that the axis of the T-shaped detection bracket 651 is aligned with the center of the sample.

[0063] The secondary drive cylinder 653 retracts the movable reference detection probe 654 to its initial position. The primary fine-tuning base 655 adjusts the movable probe mounting plate 652 so that the distance between the two probe detection surfaces is a preset value (e.g., 10 mm). The accuracy of this distance is verified using a capacitive gap sensor. The hydraulic jacking device 15 then drives the press-fit detection substrate 5 to apply rated pressure to the specimen. The secondary drive cylinder 653 extends the movable reference detection probe 654 at a rate of 0.5 mm / s until it contacts the specimen sidewall (contact force ≤ 0.5 N). The displacement data of the two probes is simultaneously recorded. The lateral adjustment frame 61 drives the sensor to scan radially along the specimen at a rate of 5 mm / s, covering a 50 mm radius around the compressed area. The detection system collects lateral indentation and tilt angle data to generate a three-dimensional deformation cloud map.

[0064] This embodiment utilizes dual-probe parallel detection technology. A fixed reference probe 656 and a movable reference probe 654 form a differential measurement system. By comparing the contact force and displacement changes between the two probes, the system eliminates interference from sample surface roughness on the test results, achieving a concavity measurement error of ≤1μm. This embodiment enables full-scale detection of pavement lateral deformation, from macroscopic contours to microscopic cracks. This provides a technical means for evaluating the resistance of pavement materials to permanent deformation, significantly enhancing the scientific nature and reliability of road engineering testing.

[0065] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above and that the invention can be embodied in other specific forms without departing from the spirit or essential characteristics of the invention. Therefore, the embodiments should be considered in all respects as illustrative and non-restrictive, and the scope of the invention is defined by the appended claims rather than the foregoing description, and it is intended that all variations that come within the meaning and range of equivalents of the claims be embraced therein.

[0066] In addition, it should be understood that although this specification is described in terms of implementation methods, not every implementation method includes only one independent technical solution. This narrative method of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment can also be appropriately combined to form other implementation methods that can be understood by those skilled in the art.

Claims

1. A pavement compressive strength measuring device, comprising a detection frame (1) and a pressing detection assembly (2); a hoisting beam (11) is disposed on the top of the detection frame (1), a downward pressure driving chamber (12) and a sample carrying chamber (13) are formed inside the frame, a hydraulic jacking device (15) is installed at the center line position of the hoisting beam (11), a driving end of the hydraulic jacking device (15) is connected to a pressing work seat (16), and the pressing detection assembly (2) is fixedly mounted on the bottom surface of the pressing work seat (16); characterized in that, The pressing detection assembly (2) comprises a detection base (3), the bottom surface of which is configured with: A pressing detection substrate (5) serves as a main pressure-applying component of the detection base seat (3); A secondary detection assembly (6) is suspended on an edge area of ​​the detection base (3) via a secondary detection hanger (4); The bottom surface of the detection base (3) is also integrated with: A hoisting base frame (7) is provided to form a structural support body; A displacement sensing frame (8) is nested inside the hoisting base frame (7), and a push assembly (9) is arranged therein; The pressing detection substrate (5) forms a mechanical connection with the driving end of the pushing component (9); When the pressing detection substrate (5) applies pressure to the road surface sample, the displacement sensing frame (8) monitors the displacement change during the pressing process in real time; the pressing detection substrate (5) is driven by the push assembly (9) to generate a preset displacement, and the detection system obtains the surface fluctuation data after the road surface is pressed; then the secondary detection assembly (6) performs a descending action to perform contact measurement on the lateral profile of the compressed area of ​​the sample to obtain possible depression or tilt deformation parameters of the road surface.

2. The pavement compressive strength measuring device according to claim 1, characterized in that: The hoisting base frame (7) is fixedly connected to the bottom plate surface of the detection base (3), and the top of the detection base (3) is rigidly mounted on the bottom surface of the pressing work seat (16) through a positioning fixed block (31); the plate body of the detection base (3) is rigidly connected to the secondary detection hanger (4) through a lateral hoisting connector (32); the bottom side edge of the hoisting base frame (7) is rigidly equipped with a fixed side plate (71), and the inner plate surface of the fixed side plate (71) is provided with a plurality of displacement guide rails (72) along the vertical direction.

3. The pavement compressive strength measuring device according to claim 2, characterized in that: The displacement sensing frame (8) includes a supporting base plate (81), and a displacement slider (82) is mounted on the side edge of the supporting base plate (81) at a position corresponding to the displacement guide rail (72); each displacement slider (82) is slidably engaged with the corresponding displacement guide rail (72) via a lateral support block (83), so that the displacement sensing frame (8) and the hoisting base frame (7) form a vertical guide mechanism; A displacement measuring sensor (84) is provided on the lateral end surface of the displacement slider (82).

4. The pavement compressive strength measuring device according to claim 3, characterized in that: The displacement measurement sensor (84) includes an elastic push rod (85) and a pressure sensing unit (86); the bottom end of the elastic push rod (85) is fixedly connected to the upper surface of the supporting base plate (81), and the top end thereof passes through the displacement slider (82) and extends to the inner surface of the top frame of the hoisting base frame (7); The pressure sensing unit (86) is embedded in the top end of the elastic top pressure rod (85) and maintains elastic contact with the inner surface of the top frame of the hoisting base frame (7), forming a dynamic measurement mechanism for pressure displacement.

5. The pavement compressive strength measuring device according to claim 4, characterized in that: The push assembly (9) includes a fixed end seat (91) and a push drive module (93), wherein the fixed end seat (91) is rigidly connected to both ends of the support base plate (81), and the push drive module (93) is mounted between the two fixed end seats (91); a precision transmission screw (92) is rotatably arranged between the two fixed end seats (91), and a push base (94) is slidably arranged on the push drive module (93), and the push base (94) forms a spiral transmission connection with the precision transmission screw (92); the bottom of the precision transmission screw (92) is fixedly connected to a hanging fixed seat (95), and a sliding groove is opened in the horizontal direction of the plate body of the support base plate (81), and the hanging fixed seat (95) is slidably embedded in the sliding groove; the top of the pressing detection substrate (5) is rigidly connected to the bottom surface of the hanging fixed seat (95) through the mounting plate body (57).

6. The pavement compressive strength measuring device according to claim 5, characterized in that: The pressing detection substrate (5) includes a substrate body (51), the bottom surface of which is provided with a plurality of detection through holes (52), the substrate body (51) being a hollow cavity structure, the inner cavity of which is horizontally provided with an inner cavity transverse support bar (58); the upper surface of the inner cavity transverse support bar (58) is fixedly equipped with a plurality of fixing buckles (59), and the inner cavity of the substrate body (51) is vertically penetrated with a plurality of detection conduits (53), each detection conduit (53) being rigidly fixed to the upper surface of the inner cavity transverse support bar (58) by a fixing buckle (59); The bottom end of each detection conduit (53) is equipped with a single-point sensor (54), which is configured in a one-to-one correspondence with the detection through hole (52), and the sensor detection end extends into the axial channel of the detection through hole (52).

7. The pavement compressive strength measuring device according to claim 6, characterized in that: A gap is formed between the detection conduits (53) in the middle area, and an azimuth angle sensor (56) is arranged in the gap. The azimuth angle sensor (56) is rigidly mounted on the inner cavity wall of the substrate body (51) and is distributed in an array around the detection conduits (53) in the area.

8. The pavement compressive strength measuring device according to claim 1, characterized in that: The secondary detection assembly (6) includes a lateral adjustment frame (61), a sliding mounting plate (62) and a lateral depression detection sensor (65); the lateral adjustment frame (61) is rigidly suspended at the bottom end of the secondary detection hanger (4), and a lateral slide rail (63) and a lateral drive push rod (64) are provided inside the lateral adjustment frame (61); the sliding mounting plate (62) forms a horizontal sliding connection with the lateral adjustment frame (61) through the lateral slide rail (63), and realizes horizontal displacement drive through the lateral drive push rod (64); the bottom surface of the sliding mounting plate (62) is vertically equipped with a lifting adjustment screw (66), and the lateral depression detection sensor (65) is rigidly connected to the bottom end of the lifting adjustment screw (66).

9. The pavement compressive strength measuring device according to claim 8, characterized in that: The main body of the lateral depression detection sensor (65) is a T-shaped detection bracket (651), and a fixed reference detection probe (656) is rigidly mounted on one side of the vertical section of the T-shaped detection bracket (651), and a movable probe mounting plate (652) is slidably connected to the surface of the horizontal section via a first-level fine-tuning base (655); The first-level fine-tuning base (655) includes a guide rail and a fine-tuning knob, so that the movable probe mounting plate (652) can be displaced and adjusted along the horizontal axis of the T-shaped detection bracket (651); a second-level driving cylinder (653) is vertically fixed to the surface of the movable probe mounting plate (652), and the driving end of the second-level driving cylinder (653) is rigidly connected to the movable reference detection probe (654).

10. The pavement compressive strength measuring device according to claim 9, characterized in that: The detection end faces of the fixed reference detection probe (656) and the bottom of the movable reference detection probe (654) are kept in a coplanar configuration. When the secondary driving cylinder (653) drives the movable reference detection probe (654) to extend, its detection end face and the detection end face of the fixed reference detection probe (656) form a parallel detection surface with an adjustable vertical spacing.

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