Full-load loading test device for simulating pile-slope-soil collaborative deformation
By designing a full-load loading test device to simulate the coordinated deformation of piles, slopes, and soil, the problems of inaccurate simulation of steep slope terrain, single load mode, and insufficient monitoring of coordinated deformation in existing technologies have been solved. This enables accurate research on micropiles under complex working conditions and provides a reliable basis for engineering design.
Patent Information
- Application Number
- CN202511694805.5
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-11-18
- Publication Date
- 2026-02-10
AI Technical Summary
Existing indoor model tests cannot realistically simulate steep slope terrain, have a single load mode, and lack monitoring of the coordinated deformation of micropiles, slopes, and soil. This results in large deviations between the measured values of pile bending moment and shear force and the actual values, and the interaction mechanism between piles, soil, and slopes is unclear.
A full-load loading test device for simulating the coordinated deformation of pile-slope-soil was designed, including an assembled model box, a full-load coupled loading system and a coordinated deformation monitoring system. It can realistically simulate steep slope terrain, integrate seepage, rainfall, vibration and uplift loads, and monitor the deformation of pile body, soil and slope surface through distributed sensors.
This study enabled precise research on the stress characteristics of micropiles under complex working conditions, quantified the cooperative deformation relationship between piles, slopes, and soil, and provided a reliable basis for engineering design.
Smart Images
Figure CN121496970A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of geotechnical engineering model testing technology, specifically to a full-load loading test device for the coordinated deformation characteristics of micropiles, slopes, and soil under steep and complex terrain. Background Technology
[0002] With the large-scale construction of hydropower, transportation, and power transmission lines in mountainous areas, the application of micropile foundations adjacent to steep slopes (slope > 45°) is becoming increasingly widespread. These micropiles must simultaneously withstand the coupled effects of multiple loads, including the slope's own weight, groundwater seepage, and earthquakes. Their safety depends on the coordinated deformation capacity of the micropile, the slope, and the surrounding soil. However, existing indoor model tests have the following key shortcomings: Limitations of terrain simulation: Traditional model boxes are mostly horizontal or have a small slope (<30°), which cannot realistically reproduce the terrain features of steep slopes (45°-75°) and the layered compaction state of the soil around the piles, especially in terrain conditions with cliffs, resulting in significant deviations (error >20%) between the test values of pile bending moment and shear force.
[0003] Single load mode: Existing tests mostly use static surcharge or uniaxial vibration loading, which makes it difficult to simultaneously simulate the multi-field coupling effects of slope stress redistribution (horizontal / vertical stress), groundwater seepage softening, seismic wave vibration, etc., and cannot reflect the cumulative damage mechanism of micropiles under actual working conditions.
[0004] Unmeasurable collaborative deformation: The test only focuses on the deformation of a single point of the pile or the overall displacement of the slope, and lacks synchronous monitoring of "slope slippage-soil stress redistribution-pile bending / shear", which leads to an unclear pile-soil-slope interaction mechanism (such as whether the pile deforms synchronously with the slope and when voids occur).
[0005] Therefore, there is an urgent need to develop a micropile model test device and method that can realistically simulate steep slope terrain, realize multi-load coupled loading, and quantify coordinated deformation, so as to provide a reliable basis for engineering design and safety assessment. Summary of the Invention
[0006] To address the shortcomings of existing technologies, this invention provides a full-load loading test device and method for simulating the coordinated deformation of piles, slopes, and soil, thereby solving the problems of inaccurate terrain simulation, single load mode, and lack of coordinated deformation monitoring in existing model tests, and realizing accurate research on the stress characteristics of micropiles under complex working conditions on steep slopes.
[0007] This invention provides the following technical solution: A full-load loading test device for simulating pile-slope-soil coordinated deformation includes: an assembled model box, which is assembled from side plates, steep slope terrain plates, and a bottom plate. The inner wall of the side plates has several steep slope reserved grooves with different inclination angles reserved along the height direction for installing the steep slope terrain plates; a full-load coupled loading system, including a groundwater seepage simulation unit, a rainfall simulation unit, an earthquake simulation unit, and a pile top composite loading unit; each unit is configured to act on the specimen in the box synchronously or at different times; and a coordinated deformation monitoring system, including strain / inclination angle sensing units arranged along the pile length, soil stress sensing units arranged along the pile perimeter, and slope deformation measurement units, for synchronously acquiring deformation and stress data of the pile, slope, and soil.
[0008] Furthermore, the side panel is composed of multiple single panels spliced together, and the single panels are provided with connecting protrusions and connecting grooves.
[0009] Furthermore, the base plate is assembled from multiple single-piece channel plates and fixedly connected to the side wing plates by bolts. The edge of the base plate connected to the side plate is welded with upward protrusions.
[0010] Furthermore, the groundwater seepage simulation unit consists of water injection holes on the bottom plate of the model box and an external water storage tank.
[0011] Furthermore, the rainfall simulation unit is a shower array placed above the assembled model box and with adjustable rainfall intensity, and the earthquake simulation unit is a shaking table that supports the entire assembled model box.
[0012] Furthermore, the assembled model box also includes an L-shaped steel column frame forming the four corner supports of the box body, and the pile top composite loading unit includes an auxiliary loading rod, an upward pulling motor and a horizontal pulling motor, with the auxiliary loading rod installed on the L-shaped steel column frame.
[0013] Furthermore, the piles are micropiles made of 3D-printed resin, with an elastic modulus that matches that of the prototype concrete.
[0014] Furthermore, the strain / tilt sensing unit includes fiber optic strain gauges and miniature inclinometers pre-embedded at intervals along the pile length.
[0015] Furthermore, the soil stress sensing unit includes miniature earth pressure cells embedded at preset intervals along the perimeter of the pile.
[0016] Furthermore, the slope deformation measurement unit includes a high-definition camera at the top of the slope and a dyed grid sprayed on the slope.
[0017] The present invention has the following beneficial technical effects: Realistic terrain simulation: This invention can realistically simulate the in-situ steep slope morphology by combining the steep slope reserved grooves on the side plate and the insertable steep slope terrain plate, including different slope gradients, different slope shapes, slope variation terrain, and geological condition variation terrain. Comprehensive load models: This invention integrates multiple load models including seepage, rainfall, vibration, uplift, and horizontal loading, covering the main load types under actual working conditions of micropiles, and revealing the synergistic failure mechanism of micropiles and slopes under multiple loads.
[0018] Cooperative deformation can be quantified: This invention quantifies the deformation relationship among the pile body, soil and slope through distributed monitoring (such as the correlation between pile curvature and soil displacement gradient), and clarifies the risk threshold of pile-slope separation, providing a precise basis for micro-design of power transmission towers in mountainous areas, bridge piles near cliffs, and high slope support. Attached Figure Description
[0019] Figure 1 This is a top view of the assembled model box of the present invention; Figure 2 This is a schematic diagram showing the shape of the two single plates of the side panel of the present invention and their connection. Figure 3 This is a side view of the assembled model box of the present invention; Figure 4 This is an overall schematic diagram of a full-load loading test device for simulating the coordinated deformation of pile-slope-soil according to the present invention.
[0020] The attached figures are labeled as follows: 1. Side plate; 2. L-shaped steel column frame; 3. Steep slope terrain plate; 4. Steep slope reserved groove; 5. Micropile; 6. Connecting protrusion; 7. Connecting groove; 8. Base plate; 9. Protrusion; 10. Vibration table; 11. Water injection hole; 12. Shower head; 13. Fiber optic strain gauge and miniature inclinometer; 14. Miniature earth pressure cell; 15. High-definition camera; 16. Motor; 17. Auxiliary loading rod. Detailed Implementation
[0021] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.
[0022] Example A full-load loading test device for simulating the coordinated deformation of pile-slope-soil includes an assembled model box, such as... Figure 1-3As shown, the assembled model box consists of side panels 1, L-shaped steel column frames 2, steep slope terrain slabs 3, and a base plate 8. Each side panel 1 has pre-drilled grooves 4 at different angles for installing the steep slope terrain slabs 3; the angles can be 45°, 60°, or 75°. The steep slope terrain slabs 3 can be flat, curved, or other special planes to simulate the shape of an actual in-situ slope. The pre-drilled grooves 4 at different angles can be used to install the steep slope terrain slabs 3, and each side panel 1 can be individually set with a slope to simulate steep slope shapes with varying gradients. All four side panels 1 of the model box have pre-drilled grooves 4, allowing for different combinations of steep slope terrain slabs 3 during foundation pouring to simulate various complex and varied steep slope terrains.
[0023] In this embodiment, as Figure 3 As shown, the base plate 8 of the assembled model box is assembled from single slotted plates, which are fixed to the side wing plates of the slotted plates with bolts. The outermost single slotted plate has an upward-facing protrusion 9 welded on it for connecting to the side plate 1. Figure 2 As shown, the side panel 1 can be composed of multiple single panels spliced together, and the single panels are provided with connecting protrusions 6 and connecting grooves 7.
[0024] like Figure 4 As shown, the device also includes a full-load coupled loading system and a collaborative deformation monitoring system. The full-load coupled loading system includes a groundwater seepage simulation unit, a rainfall simulation unit, an earthquake simulation unit, and a pile top composite loading unit; each unit is configured to act synchronously or at different times on the specimen inside the chamber. The groundwater seepage simulation unit consists of a pre-drilled hole 11 on the bottom plate 8 and an external water storage tank, into which water of different depths is injected to simulate different groundwater levels; the rainfall simulation unit uses a shower head 12 for simulation; the earthquake simulation unit can simulate earthquake loads on a shaking table 10; an auxiliary loading rod 17 can be installed on the L-shaped steel column frame 2 to install a motor 16 for vertical upward pulling and horizontal pulling, simulating a combination of horizontal and upward loads.
[0025] The collaborative deformation monitoring system includes strain / tilt sensing units deployed along the pile length, soil stress sensing units deployed around the pile, and slope deformation measurement units, used to simultaneously acquire deformation and stress data of the pile, slope, and soil. Specifically, this embodiment uses micropiles 5 with a diameter of 100-200mm, scaled down to 1:50-1:100 and 3D printed with resin (elastic modulus matched to the prototype concrete, error <5%). The strain / tilt sensing units consist of fiber optic strain gauges and micro inclinometers 13 pre-embedded every 50mm along the pile length on the surface of the micropiles 5 to monitor the pile strain, curvature, and tilt. The soil stress sensing units consist of micro earth pressure cells 14 (range 0-1MPa, accuracy ±1%FS, spacing 200mm) arranged within a 50mm radius around the pile to simultaneously acquire the normal stress at the pile-soil interface; the slope deformation measurement unit consists of a high-definition camera 15 installed at the top of the slope, which uses dyed grid strips to observe slope deformation in real time.
[0026] The installation method of the device of the present invention includes the following steps: 1) Pre-positioning: Place the four L-shaped steel column frames 2 in the vibration table 10 according to the design spacing, align the column base plate with the foundation hole, insert the anchor bolts and tighten them initially to form a "U"-shaped four corner support, but keep the column body slightly tiltable; 2) Install the base plate: Secure the single grooved base plate 8 along the side wing plate with bolts to form a whole base plate 8; leave gaps between the upward protrusions 9 on the four edges of the base plate 8 and the inner side of the flange of the L-shaped steel column frame 2 to facilitate the subsequent insertion of the side plate 1; fix the four corners of the base plate to the vibration table 10 with anchor bolts. 3) Determine the overall terrain and slope: Select the slope combination according to the test plan, and use a marker to mark the boundary line of each soil sample layer and the location of the gap near the cliff on the surface of the bottom plate 8; 4) Processing steep slope terrain board 3: Cut steep slope terrain board 3 according to the marked dimensions. Steep slope terrain board 3 can be flat, curved or other special plane. 5) Install the first side panel 1 and the steep slope terrain plate 3: Align the flange holes at both ends of the first side panel 1 with the flange holes of the L-shaped steel column frame 2, insert the bolts and tighten them; slide the processed steep slope terrain plate 3 from top to bottom into the inner steep slope reserved groove 4 of the side panel 1. 6) Installation and layer-by-layer filling of the second side panel 1 and steep slope terrain panel 3: Fill in layers and compact the soil sample to the designed density until the target slope height is reached; 7) Installation of the full load coupled loading system: a. Groundwater loading: Connect quick-connect fittings to the water injection holes 11 on the bottom slab → lay the filter layer → connect the water storage tank → form a seepage path; b. Rainfall loading: Hoist aluminum profile beams on top of the model box → Fix 12-sprinkler array → Connect water supply pipe, pressure regulator, and flow meter; c. Seismic loading: Anchoring the four corners of the base plate to the shaking table 10 → Final tightening of the anchor bolts of the L-shaped steel column frame 2 → Checking the levelness of the table surface ≤1 mm / m; d. Composite loading at the pile top: Connect the auxiliary loading rod 17 to the top of the L-shaped steel column frame 2 → suspend the servo motor → install the force-displacement sensor → connect the steel wire rope to the pile top clamp after passing through the fixed pulley; 8) Installation of the collaborative deformation monitoring system: a. Pile body monitoring: shallow groove is opened along the axis of the micropile 5 → fiber optic strain gauge and micro inclinometer 13 are pre-embedded → epoxy is poured into the groove → the tail fiber is led out through the top gland; b. Soil monitoring: Embed miniature earth pressure cells 14 at preset positions around the pile → fix the cable along the inner wall of the side plate with clips → collect the data via the gland head to the data acquisition instrument; c. Slope monitoring: Install a high-definition camera 15 on the top beam of the model box → adjust the viewing angle to cover the slope → spray and dye the grid → synchronize the camera and the data acquisition instrument clock.
[0027] 9) Sealing and protection: Apply silicone strips to the flange of the base plate → tighten the bolts of the angle steel pressure strip, and complete the overall inspection.
[0028] This device can be widely used in the research and design verification of the synergistic deformation mechanism of micropile foundations such as power transmission line tower foundations in mountainous areas, bridge piles on steep slopes, and foundations of buildings near cliffs. It has significant technological advancement and engineering promotion value.
[0029] The embodiments described above are merely illustrative of specific implementations of the present invention, and while the descriptions are detailed, they should not be construed as limiting the scope of the present invention. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these modifications and improvements all fall within the scope of protection of the present invention.
Claims
1. A full-load loading test device for simulating the coordinated deformation of pile-slope-soil, comprising: The assembled model box is composed of side panels, steep slope terrain panels and bottom plates. The inner wall of the side panels has several steep slope reserved grooves with different inclination angles reserved along the height direction for installing steep slope terrain panels. The full load coupled loading system includes a groundwater seepage simulation unit, a rainfall simulation unit, an earthquake simulation unit, and a pile top composite loading unit; each unit is configured to act synchronously or at different times on the specimen inside the chamber. The collaborative deformation monitoring system includes strain / tilt sensing units deployed along the pile length, soil stress sensing units deployed within a preset range around the pile, and slope deformation measurement units, which are used to simultaneously acquire deformation and stress data of the pile, slope, and soil.
2. The full-load loading test device for simulating pile-slope-soil coordinated deformation according to claim 1, characterized in that, The side panel is composed of multiple single panels spliced together, and the single panels are provided with connecting protrusions and connecting grooves.
3. The full-load loading test device for simulating pile-slope-soil coordinated deformation according to claim 1, characterized in that, The base plate is assembled from multiple single-piece channel plates and is fixedly connected to the side wing plates by bolts. The edge of the base plate connected to the side plate has upward protrusions welded on it.
4. The full-load loading test device for simulating pile-slope-soil coordinated deformation according to claim 1, characterized in that, The groundwater seepage simulation unit consists of water injection holes in the base plate and an external water storage tank.
5. The full-load loading test device for simulating pile-slope-soil coordinated deformation according to claim 1, characterized in that, The rainfall simulation unit is a shower array placed above the assembled model box with adjustable rainfall intensity, and the earthquake simulation unit is a shaking table that supports the entire assembled model box.
6. The full-load loading test device for simulating pile-slope-soil coordinated deformation according to claim 1, characterized in that, The assembled model box also includes an L-shaped steel column frame that forms the four corner supports of the box body. The pile top composite loading unit includes an auxiliary loading rod, an upward pulling motor and a horizontal pulling motor. The auxiliary loading rod is installed on the L-shaped steel column frame.
7. The full-load loading test device for simulating pile-slope-soil coordinated deformation according to claim 1, characterized in that, The device uses 3D-printed resin micropiles whose elastic modulus matches that of the prototype concrete.
8. The full-load loading test device for simulating pile-slope-soil coordinated deformation according to claim 1, characterized in that, The strain / tilt sensing unit includes fiber optic strain gauges and miniature inclinometers that are pre-embedded at intervals along the length of the pile.
9. The full-load loading test device for simulating pile-slope-soil coordinated deformation according to claim 1, characterized in that, The soil stress sensing unit includes miniature earth pressure cells embedded at preset intervals along the perimeter of the pile.
10. The full-load loading test device for simulating pile-slope-soil coordinated deformation according to claim 1, characterized in that, The slope deformation measurement unit includes a high-definition camera at the top of the slope and a dyed grid sprayed on the slope.