Test apparatus and method for horizontal reinforcement composite foundation resisting strong earthquake surface faults

Abstract

The application discloses a kind of horizontal reinforcement composite foundation test device and method of anti-strong earthquake ground surface fracture, and belongs to the field of building anti-seismic technology, specifically relates to a kind of horizontal reinforcement composite foundation test device and method of anti-strong earthquake ground surface fracture.Testing before including the debugging of bedrock dislocation loading system, the debugging of data acquisition analysis system and sensor, the preparation of test model material, the arrangement of test model and sensor;Data analysis anti-fracture capacity comprehensive evaluation after testing, including qualitative analysis of test phenomenon, quantitative analysis of test data.In the test, by building geogrid transverse reinforcement composite foundation, reduce or reduce the obvious shear fracture of ground surface fault caused by strong earthquake ground surface fault in overburden layer, and the related hazards caused by this, such as significant non-uniform deformation or tensile crack of site surface.Not only can improve the stability of foundation, but also effectively divert potential fracture trace to outside the range of building foundation, to protect the safety of upper building.

Description

Technical Field

[0001] This invention belongs to the field of seismic resistance technology for buildings, specifically relating to a test device and method for a horizontally reinforced composite foundation resistant to strong earthquake surface fracture. Background Technology

[0002] In the field of earthquake engineering, surface fault rupture is generally considered one of the main sources of earthquake damage to buildings near faults. Its destructive impact on building structures and infrastructure can not only lead to severe structural damage but also cause casualties. The hazards associated with surface faults mainly include significant shear fracturing of the soil and rock mass within the overburden layer, forming plastic zones, and resulting in significant uneven deformation or tensile cracks on the site surface.

[0003] To address these hazards, the design and implementation of geosynthetic reinforced soil transverse reinforcement foundations has become an effective technical approach. This foundation reinforcement method aims to enhance the bearing capacity of the soil and control uneven deformation caused by fault activity within acceptable limits. In other words, by constructing transverse reinforcement foundations, uneven surface settlement can be effectively reduced, and potential rupture lines can be diverted outside the building foundation area, thereby maintaining the safety of the superstructure.

[0004] This invention aims to explore and verify the effectiveness and feasibility of horizontally reinforced composite foundations in mitigating earthquake damage to buildings and structures caused by surface fault rupture through experimental and applied research. This approach is expected to provide fundamental technical data support for the design and construction of buildings and structures in earthquake-prone areas, and further provide technical assurance for earthquake disaster prevention and mitigation planning in these regions. Summary of the Invention

[0005] In order to solve the technical problems existing in the background art, the present invention aims to provide a test device and method for horizontally reinforced composite foundations that resist strong earthquake surface fractures, to evaluate the ability of reinforced soil foundations to resist fault rupture zones, so as to reduce the harm of uneven deformation of building foundations caused by fault rupture zones in earthquakes.

[0006] To solve the technical problem, the technical solution of the present invention is as follows:

[0007] A test device for a horizontally reinforced composite foundation resistant to strong earthquake surface fractures, characterized in that it includes a test bedrock dislocation loading system, a data acquisition and analysis system and sensors, and a building model;

[0008] The experimental bedrock dislocation loading system includes the overall debugging of the hydraulic control system, four actuators, dislocation box and wire displacement meter;

[0009] The hydraulic control system includes a hydraulic control panel, a displacement signal display panel, a hydraulic output area, and a displacement signal receiving area;

[0010] The aforementioned dislocation test chamber includes high-strength resin glass test observation areas on the front and rear sides and steel plates on the left and right sides. The bottom of the chamber is equipped with a simulated bedrock “L”-shaped dislocation steel plate and a simulated bedrock stationary plate. A gap is left at the junction of the simulated bedrock “L”-shaped dislocation steel plate and the simulated bedrock stationary plate to simulate the fracture zone.

[0011] The displaced box contains a compacted soil cover layer; the area above the simulated bedrock “L”-shaped dislocation steel plate is the simulated cover layer I zone, the area above the simulated bedrock stationary plate is the simulated cover layer II zone, and the part at the junction of the two zones is the geogrid arrangement zone.

[0012] The geogrid placement area has grooves for placing the building foundation at the bottom of the building model; the geogrid is placed below the building foundation.

[0013] There are four actuators, located at the four corners of the simulated bedrock “L”-shaped dislocation steel plate; each actuator is equipped with a wire displacement meter; the wire displacement meter is fixed at the support plate below the actuator, and the wire magnet head of the wire displacement meter is vertically and upwardly attracted to the lower side of the “L”-shaped dislocation steel plate.

[0014] The signal receiving line of the wire displacement gauge is connected to its respective displacement signal receiving area of ​​the hydraulic control system; the actuator is connected to the hydraulic output area of ​​the hydraulic control system via a hydraulic oil pipe.

[0015] The sensors include earth pressure gauges, strain gauges, laser displacement gauges, and high-speed cameras; the data acquisition and analysis system is connected to each sensor.

[0016] The high-speed camera is placed directly in front of the sliding housing;

[0017] Multiple earth pressure gauges were placed above the junction of the simulated bedrock “L”-shaped dislocation steel plate and the simulated bedrock stationary plate to monitor the changes in earth pressure increments during the normal fault dislocation process; the earth pressure gauges were placed in the areas where the first and second rupture traces developed during the normal fault bedrock dislocation process.

[0018] Strain gauges are spaced on the geogrid to analyze the fracture resistance of the horizontally reinforced composite foundation.

[0019] Three-dimensional strain gauges were arranged at equal intervals according to the story height on the outer side of the building edge columns of the building model to monitor the strain of the building edge columns during the test, in order to analyze the fracture resistance of the horizontally reinforced composite foundation.

[0020] Multiple laser displacement gauges are arranged on a crossbeam above the soil cover layer to analyze the uneven deformation of the ground surface.

[0021] This invention also provides a test method for a horizontally reinforced composite foundation resistant to strong earthquake surface fractures, using the above-mentioned apparatus, the method comprising:

[0022] The bedrock dislocation loading system was debugged. The bedrock dislocation loading system includes a hydraulic control system, four actuators, a dislocation box, and a wire displacement meter.

[0023] The data acquisition and analysis system and sensors are debugged, including soil pressure gauges, strain gauges, laser displacement gauges and high-speed cameras;

[0024] The test model materials are prepared, including a building model, a geogrid in the transverse reinforcement, and a cover soil layer.

[0025] The test models and sensors were arranged, including the arrangement of the overburden soil, the geogrid, the building model, the earth pressure gauges, the geogrid strain gauges, the building model strain gauges, and the laser displacement gauges.

[0026] Preparatory work and experimental process were carried out before the test, bedrock displacement was gradually loaded, and multiple working condition tests were conducted.

[0027] Finally, quantitative and qualitative analysis of the data results was conducted, including the tilt angle of the building model, the increment of earth pressure in the overburden, the increment of geogrid strain, the increment of building model strain, and the deformation analysis of the building model foundation.

[0028] Furthermore, the debugging method for the experimental bedrock dislocation loading system includes:

[0029] Adjust the wire displacement gauges by fixing the four wire displacement gauges to the support plates below the four actuators. Attach the wire magnets of the wire displacement gauges vertically upwards to the underside of the "L"-shaped dislocation steel plate. Use a spirit level to measure and adjust the verticality of the wire displacement gauges until the horizontal bubble is centered.

[0030] Connect the signal receiving lines of the four wire displacement gauges to their respective displacement signal receiving areas of the hydraulic control system. Then start the hydraulic control system and slowly pull out the wires of the wire displacement gauges by 1 cm. Observe whether the displacement signal on the hydraulic control display panel is 1 cm, with an error of ±0.1%.

[0031] Connect the actuator to the hydraulic output area of ​​the hydraulic control system with a hydraulic hose and check its sealing. Then, input the jacking rate as 1 mm / s and the bedrock jacking amount as 10 mm on the hydraulic control panel and wait for the actuator to complete the jacking. Then, use a level to measure the positions of the four upper corners of the "L"-shaped dislocation steel plate and observe whether the bubble on the level is centered.

[0032] Furthermore, the debugging of the data acquisition and analysis system and sensors includes debugging of the earth pressure gauge, strain gauge, laser displacement gauge and high-speed camera;

[0033] The commissioning of the earth pressure gauge includes connecting the earth pressure gauge to the data acquisition and analysis system, calibrating the earth pressure gauge using the water level method, and observing whether the collected earth pressure and the calculated value are consistent through the data display window of the data acquisition and analysis system.

[0034] Fix the earth pressure gauge at the 0cm position of the end of a 1m graduated steel ruler, connect it to the data acquisition and analysis system and zero it. Then place it at 10cm, 50cm and 100cm below the horizontal plane respectively and let it stand for 10 seconds. Observe whether the difference between the earth pressure in the data acquisition and analysis system and the actual value is within ±5% and adjust the earth pressure sensitivity parameter.

[0035] The debugging of the laser displacement gauges includes: numbering multiple laser displacement gauges and connecting them sequentially to the data acquisition and analysis system; fixing the laser displacement gauges to the same side of the square steel beam with double-sided tape, ensuring that the laser emission areas are on the same side; placing a rectangular wooden board 20cm in front of the laser displacement gauge emission area, ensuring that the distance data of the laser displacement gauges in the data acquisition and analysis system is 20cm; moving the rectangular wooden board 10cm away from the laser displacement gauges; and observing whether the data of multiple laser displacement gauges in the data acquisition and analysis system are within ±5% of the actual value of 30cm.

[0036] The debugging of the high-speed camera includes: placing the high-speed camera directly in front of the test misalignment box, adjusting the camera range until the entire test misalignment box is within the field of view of the high-speed camera, analyzing the photos of the soil containing the fracture zone, observing whether there is distortion in the photos of the test misalignment box, and adjusting the exposure and angle parameters of the high-speed camera.

[0037] Furthermore, the arrangement of the experimental model and sensors specifically includes:

[0038] The arrangement of the cover soil is as follows: a 100cm soil cover layer is compacted within the shifted box; 15cm of loose soil is placed at a time, and compaction is carried out starting from the leftmost side of the shifted box with a tamping hammer. The first compaction is carried out with the tamping hammer to compact the loose soil to 13cm, followed by a second compaction to compact the soil layer to 12cm, and then a third compaction to reach 10cm. After compacting the soil layer to 70cm using the above method, geogrid transverse reinforcements are arranged in the soil layer from 70cm to 100cm, and the soil layer is compacted again using the above method.

[0039] The arrangement of geogrids includes: arranging geogrids with the most unfavorable fault displacement position as the center according to the building model; arranging geogrids in the geogrid arrangement area; after laying strain gauges and connecting lines on the four corners with loose soil; laying loose soil with a height of 15cm and compacting it to 10cm with a tamping hammer; and measuring and correcting it with a spirit level until it is level.

[0040] The arrangement of the building model includes: placing the building model at the most unfavorable position of the fault displacement, excavating a square trench 8cm deep vertically on the ground surface, placing the building model foundation in the trench and filling it with 9cm of loose soil, compacting and leveling it to be at the same height as the surface of the overburden soil.

[0041] The arrangement of earth pressure gauges includes: earth pressure gauges are placed in the area where rupture traces develop during the dislocation of the normal fault bedrock. Nine earth pressure gauges are placed directly above the junction of the two blocks at intervals of 10 cm to monitor the changes in earth pressure increments during the rupture of the rupture traces during the dislocation of the normal fault.

[0042] The arrangement of strain gauges on the geogrid includes: arranging 10 strain gauges with a spacing of 10cm in the middle of the geogrid to analyze the fracture resistance of the horizontally reinforced composite foundation.

[0043] The arrangement of building strain gauges includes: placing triaxial strain gauges, i.e. building edge column strain gauges, at equal intervals according to the story height on the outside of the building edge columns of the building model to monitor the strain of the building edge columns during the test, in order to analyze the fracture resistance of the horizontally reinforced composite foundation;

[0044] The arrangement of the laser displacement gauges includes: multiple laser displacement gauges are arranged on the crossbeam 20cm above the overburden layer, starting from the inner steel plate on the right side of the misaligned box, at intervals of 40cm, to analyze the uneven deformation of the ground surface.

[0045] Furthermore, the gradual loading of bedrock displacement and the conduct of multiple working condition tests include:

[0046] Start the data acquisition and analysis system to collect test data; start the hydraulic control system, first synchronously lift 1mm, and observe whether the sensor reading is normal; perform 10 working conditions respectively, and each time the wire displacement gauge is given a bedrock displacement input of 10mm. Before each test, the data acquisition is cleared.

[0047] Furthermore, the quantitative and qualitative analysis of the test results includes: the tilt angle of the building model, the analysis of the incremental earth pressure in the overburden layer, the analysis of the incremental strain of each layer of geogrid (i.e., whether the strain of the geogrid adjacent to the building model changes significantly), the analysis of the incremental strain of the building model, whether the foundation of the building model passes through the rupture zone, and whether the foundation of the building model produces significant uneven deformation (i.e., whether a stepped steep slope is produced).

[0048] Compared with the prior art, the advantages of the present invention are as follows:

[0049] (a) The test scheme and method for a horizontally reinforced composite foundation resisting strong earthquake surface fault zones provided by the present invention is a mature method for conducting tests on horizontally reinforced composite foundations resisting strong earthquake surface fault zones.

[0050] (b) The present invention provides a test scheme and method for a horizontally reinforced composite foundation that resists strong earthquake surface fault zones. It can change the number of geogrid layers added to the overburden layer and study the ability of geogrids with different numbers of layers to resist the development of strong earthquake surface fault zones.

[0051] (c) The present invention provides a test scheme and method for a horizontally reinforced composite foundation resisting strong earthquake surface fault zones, which can change the type of overburden and study the ability of the transverse reinforcement under different overburden layers to resist strong earthquake surface faults.

[0052] (d) The present invention provides a test scheme and method for a horizontally reinforced composite foundation resisting strong earthquake surface fault zones. Earth pressure is placed along the centerline at the junction of an "L"-shaped dislocation steel plate simulating bedrock and a stationary plate simulating bedrock in the overburden layer. This allows monitoring of earth pressure changes in the overburden layer during the test to analyze the fracture resistance of the horizontally reinforced composite foundation. Strain gauges are placed on the geogrid to monitor its strain during the test, further analyzing the fracture resistance of the horizontally reinforced composite foundation. Triaxial strain gauges are placed at equal intervals according to the floor height on the outer side of the building's edge columns to monitor their strain during the test, also analyzing the fracture resistance of the horizontally reinforced composite foundation.

[0053] (e) Compared with other test methods, this test adds a comprehensive evaluation table of the horizontal reinforcement's resistance to fracture. After the test, quantitative and qualitative analysis indicators are filled into the evaluation table based on the data from the data acquisition and analysis system. This provides a quantitative comparison of the horizontal reinforcement's ability to resist the development of surface fault zones during strong earthquakes, thus improving the reliability of the test results. Attached Figure Description

[0054] Figure 1 This is a schematic diagram of the device arrangement provided in an embodiment of the present invention;

[0055] Figure 2 This is a schematic diagram of a building model on a cover layer provided in an embodiment of the present invention;

[0056] Figure 3 A schematic diagram of a geogrid provided in an embodiment of the present invention;

[0057] Figure 4 A schematic diagram of the experimental model materials provided in the embodiments of the present invention;

[0058] Figure 5 A schematic diagram showing the arrangement of sensors according to an embodiment of the present invention;

[0059] Figure 6 A flowchart of the test method provided in an embodiment of the present invention. Detailed Implementation

[0060] The specific implementation of the present invention is described below with reference to embodiments:

[0061] It should be noted that the structures, proportions, sizes, etc. shown in this specification are only used to complement the content disclosed in the specification for those skilled in the art to understand and read, and are not intended to limit the conditions under which the present invention can be implemented. Any modifications to the structure, changes in the proportions, or adjustments to the size, without affecting the effects and objectives that the present invention can produce, should still fall within the scope of the technical content disclosed in the present invention.

[0062] Furthermore, the terms such as "upper," "lower," "left," "right," "middle," and "one" used in this specification are merely for clarity of description and are not intended to limit the scope of the invention. Any changes or adjustments to their relative relationships, without substantially altering the technical content, should also be considered within the scope of the invention.

[0063] Example 1:

[0064] This embodiment provides a test method for a horizontally reinforced composite foundation that resists strong earthquake surface rupture, including the debugging of the bedrock dislocation loading system, the debugging of the data acquisition and analysis system 8 and sensors, the preparation of test model materials, the arrangement of the test model and sensors, and the comprehensive analysis of quantitative and qualitative data results.

[0065] (1) Debugging of the bedrock dislocation loading system, including overall debugging of the hydraulic control system 1, four actuators 2, dislocation box 7, and wire displacement meter 3.

[0066] like Figure 1 As shown, the experimental bedrock dislocation loading system includes the overall debugging of the hydraulic control system 1, four actuators 2, the dislocation box 7 and the wire displacement meter 3;

[0067] The hydraulic control system 1 includes a hydraulic control panel, a displacement signal display panel, a hydraulic output area, and a displacement signal receiving area;

[0068] The dislocation chamber 7 includes high-strength resin glass test observation areas on the front and rear sides and steel plates on the left and right sides. The bottom of the chamber is provided with simulated bedrock “L”-shaped dislocation steel plate 4 and simulated bedrock stationary disk steel plate 9. A gap is left at the junction of the simulated bedrock “L”-shaped dislocation steel plate 4 and the simulated bedrock stationary disk steel plate 9 to simulate the fracture zone.

[0069] The displaced box 7 is equipped with a compacted soil cover layer; the simulated bedrock “L”-shaped dislocation steel plate 4 is above the simulated cover layer I zone 14, the simulated bedrock stationary plate 9 is above the simulated cover layer II zone 15, and the part at the junction of the two zones is the geogrid arrangement zone 16.

[0070] The first step is to debug the wire displacement gauges 3. Fix the four wire displacement gauges 3 to the support plate below the actuator 2. Attach the magnetic head of the wire displacement gauge 3 vertically upwards to the underside of the "L"-shaped dislocation steel plate 4, and use a spirit level to measure the wire of the wire displacement gauge 3 until the bubble is centered.

[0071] Furthermore, the signal receiving lines of the four wire displacement gauges 3 are connected to their respective displacement signal receiving areas of the hydraulic control system 1. Then, the hydraulic control system 1 is started and the wires of the wire displacement gauges 3 are slowly pulled out by 1 cm. The displacement signal on the hydraulic control display panel is observed to be 1 cm, with an error of ±0.1%.

[0072] Further, connect the actuator 2 to the hydraulic output area of ​​the hydraulic control system 1 with a hydraulic oil pipe and check its sealing performance; then, input the jacking rate as 1mm / s and the bedrock jacking amount as 10mm on the hydraulic control panel, and wait for the actuator 2 to complete the jacking; next, use a spirit level to measure the positions of the four upper corners of the "L"-shaped dislocation steel plate 4 and observe whether the bubble on the spirit level is centered.

[0073] (2) The debugging of the data acquisition and analysis system 8 and the sensors includes debugging the earth pressure gauge 21, strain gauge, laser displacement gauge 5 and high-speed camera 10 used.

[0074] The debugging of earth pressure gauge 21 includes connecting earth pressure gauge 21 to data acquisition and analysis system 8, calibrating earth pressure gauge 21 using the water level method, and observing whether the collected earth pressure and the calculated value are consistent through the data display window of data acquisition and analysis system 8.

[0075] Furthermore, the earth pressure gauge 21 is fixed at the "0cm" position on the end of a 1m long steel ruler with graduations, connected to the data acquisition and analysis system 8 and zeroed. Then, it is placed at 10cm, 50cm, and 100cm below the horizontal plane and left to stand for 10 seconds. The difference between the earth pressure in the data acquisition and analysis system 8 and the actual value (0.98kPa, 4.9kPa, and 9.8kPa respectively according to the water pressure calculation method) is observed to be within ±5%. The earth pressure sensitivity parameter is then adjusted.

[0076] The debugging of the laser displacement gauges 5 includes, preferably, numbering the nine laser displacement gauges 5 (number 1-9) and connecting them sequentially to the data acquisition and analysis system 8. The laser displacement gauges 5 are fixed to the same side of the square steel beam with double-sided tape, ensuring the laser emission areas are on the same side. A rectangular wooden board is placed 20cm in front of the emission area of ​​each laser displacement gauge 5, ensuring the distance between the nine laser displacement gauges 5 in the data acquisition and analysis system 8 is 20cm. The rectangular wooden board is then moved 10cm away from the laser displacement gauges 5. The data from the nine laser displacement gauges 5 in the data acquisition and analysis system 8 is observed to be within ±5% of the actual value of 30cm.

[0077] The debugging of the high-speed camera 10 includes placing the high-speed camera 10 directly in front of the test misalignment box 7, adjusting the camera range until the entire test misalignment box 7 is within the field of view of the high-speed camera 10, analyzing the photographs of the soil containing the fracture zone, observing whether there is distortion in the photographs of the test misalignment box 7, and adjusting the exposure and angle parameters of the high-speed camera 10.

[0078] (3) Experimental model materials and processing include the preparation of building model 6, the preparation of geogrid 22 in the transverse reinforcement, and the preparation of overburden soil.

[0079] The preparation of building model 6, such as Figure 2 As shown, the construction includes the building's side columns 11, floor slabs 12, and foundation 13. Preferably, the steel structure building model 6 in this invention adopts a six-story 65Mn steel structure with a similarity ratio of 1:20, a floor height of 15cm, and a floor slab side length of 30cm. The side columns are rectangular steel plates with a length of 81cm and a width of 1.5cm. The foundation 13 is preferably constructed using a reinforced concrete structure with a similarity ratio of 1:20, with a length, width, and height of 20cm, 20cm, and 3cm respectively. Preferably, the material ratio in this invention is cement:gypsum:sand:water = 3:12:30:12, the compressive strength is 3.75MPa, and the independent foundation structure uses Φ2.4@25 steel wire mesh with a mesh size of 19cm×19cm.

[0080] like Figure 3The preparation of the geogrid 22 in the transverse reinforcement includes, preferably, the geogrid 22 in this invention is a polyester biaxial welded geogrid with a tensile strength of 40 KN / m. 2 It is 1730mm long and 1000mm wide, with a spacing of 5cm between the horizontal and vertical ribs and a thickness of 1mm.

[0081] The preparation of the overburden soil includes, preferably, the use of natural clay foundation with a moisture content of 10% in this invention.

[0082] The first step, according to the present invention, uses approximately 15m of material to measure the dimensions of the experimental model (4.6m × 1.8m × 1m). 3 The clay was initially sieved using a 5mm mesh screen.

[0083] Furthermore, five soil samples were randomly selected from the sieved soil pile for moisture content determination tests, and the average moisture content was calculated.

[0084] Furthermore, soil with high moisture content is placed on waterproof tarpaulin to dry and its moisture content is measured periodically; for soil with low moisture content, its water requirement is calculated based on its current moisture content, and water is sprayed in layers on the soil pile using a sprinkler. After stirring evenly with a shovel, its moisture content is measured until it meets the requirements.

[0085] Furthermore, the soil that meets the requirements is packed into 10kg waterproof woven bags, and then stacked on double-sided waterproof canvas. After stacking, a water-soaked sponge net is laid on top of the soil pile, and the double-sided waterproof canvas is covered on the woven bag soil pile. Finally, the soil pile is compacted and sealed around it.

[0086] (4) The arrangement of test model materials and sensors includes the arrangement of the overburden soil, the arrangement of the geogrid 22, the arrangement of the building model 6, the arrangement of the earth pressure gauge 21, the arrangement of the geogrid strain gauge 17, the arrangement of the strain gauge of the building model 6, and the arrangement of the laser displacement gauge 5.

[0087] The soil cover layer was arranged by compacting a 100cm soil cover layer within the sliding box 7.

[0088] Furthermore, each time 15cm of loose soil is placed, it is compacted starting from the leftmost side of the misaligned box 7 with a tamping hammer. The first compaction is carried out with the tamping hammer to compact the loose soil to 13cm. Then, the soil layer is compacted a second time with the tamping hammer to compact the soil layer to 12cm, until the third compaction is carried out to reach 10cm.

[0089] Furthermore, after compacting the soil layer to 70cm using the above method, geogrid 22 transverse reinforcements are arranged in the soil at the corresponding positions within the 70cm to 100cm soil layer, and the soil layer is compacted again using the above method.

[0090] The arrangement of the geogrid 22 includes arranging the geogrid 22 with the most unfavorable position of the fault displacement as the center according to the building model 6.

[0091] like Figure 4 The displaced box 7 is equipped with a compacted soil cover layer; the simulated bedrock “L”-shaped dislocation steel plate 4 is above the simulated cover layer I zone 14, the simulated bedrock stationary plate 9 is above the simulated cover layer II zone 15, and the part at the junction of the two zones is the geogrid arrangement zone 16.

[0092] Furthermore, geogrid 22 is arranged in geogrid arrangement area 16. After the geogrid strain gauges 17 and connecting lines are laid on the four corners with loose soil, a layer of loose soil with a height of 15cm is laid and compacted to 10cm with a tamping hammer. The soil is then measured and corrected with a spirit level until it is level.

[0093] The arrangement of building model 6 includes placing building model 6 at the most unfavorable position of fault displacement in this invention. Preferably, the center of the foundation bottom surface of building model 6 is located at the halfway point of the boundary line between the two blocks.

[0094] Furthermore, a square trench 8cm deep was dug vertically on the ground surface, the building foundation 13 was placed in the trench and filled with 9cm of loose soil, which was then compacted and leveled to be at the same height as the surface of the overburden soil.

[0095] like Figure 5 The arrangement of the earth pressure gauges 21 includes placing the earth pressure gauges 21 in the area where the fracture traces develop during the dislocation of the normal fault bedrock. Nine earth pressure gauges 21 are arranged directly above the junction of the two blocks, spaced 10 cm apart, in order to monitor the earth pressure increment changes during the rupture of the first fracture trace 19 and the second fracture trace 20 during the dislocation of the normal fault.

[0096] The arrangement of the geogrid strain gauges 17 includes 10 strain gauges spaced 10 cm apart in the middle of the geogrid 22, which are used to analyze the fracture resistance of the horizontally reinforced composite foundation.

[0097] The arrangement of strain gauges 18 on the building edge columns includes arranging triaxial strain gauges at equal intervals according to the floor height on the outside of the building edge columns 11 to monitor the strain of the building edge columns 11 during the test, in order to analyze the fracture resistance of the horizontally reinforced composite foundation.

[0098] The arrangement of the laser displacement gauges 5 includes nine laser displacement gauges 5 arranged at 40cm intervals on the crossbeam 20cm above the overburden layer, starting from the inner steel plate on the right side of the misaligned box 7, to analyze the uneven deformation of the ground surface.

[0099] (5) Complete the preparatory work for the experiment according to the above steps, and then conduct the experiment.

[0100] The first step is to start the data acquisition and analysis system 8 to collect experimental data.

[0101] Next, activate hydraulic control system 1, first synchronously lift by 1mm, and observe whether the sensor readings are normal.

[0102] Furthermore, 10 working conditions were tested, with each test using a 3-meter wire displacement meter to input 10mm of bedrock displacement. Before each test, the data acquisition was cleared.

[0103] (6) Quantitative and qualitative analysis of the test results include the building tilt angle, analysis of the increase in earth pressure in the overburden layer, analysis of the increase in strain of each layer of geogrid (whether the strain of the geogrid adjacent to the building changes significantly), analysis of the increase in building strain, whether the building foundation passes through the rupture zone, and whether the building foundation produces significant uneven deformation (whether a stepped steep slope is produced).

[0104] This invention also provides a comprehensive evaluation table of the fracture resistance of horizontal reinforcement (Table 1), and, in conjunction with the above test scheme, provides a test method for horizontal reinforcement composite foundations resisting strong earthquake surface fault zones, such as... Figure 6 .

[0105] Table 1. Comprehensive Evaluation of Fracture Resistance of Horizontal Reinforcement

[0106] project Result (Fill in "Yes" or "No") Does the building foundation exhibit significant uneven deformation? Is the building tilting? Did the building's transverse reinforcement foundation pass through the fracture trace? Does the strain change of the building's edge columns exceed 50 με? Does the strain change on the far right side of the geogrid at the top of the foundation exceed 100 με? Does the change in earth pressure at a height of 50cm in the overburden layer exceed 5kPa?

[0107] Note: The table shows the comprehensive evaluation of the fracture resistance of horizontal reinforcements;

[0108] If the number of "No" results in the cumulative evaluation table is greater than or equal to 5, then the fracture resistance of the horizontal reinforcement is "Excellent".

[0109] If the number of "No" results in the cumulative results of the evaluation form is greater than or equal to 4 but less than 5, then the fracture resistance of the horizontal reinforcement is "Good".

[0110] If the number of "No" results in the cumulative results of the evaluation table is less than 4, then the fracture resistance of the horizontal reinforcement is "poor".

[0111] Example 2:

[0112] This embodiment provides a test method for a horizontally reinforced composite foundation resistant to strong earthquake surface fractures, referring to... Figures 1-6 See Table 1.

[0113] In the actual experiment, the cover layer was fully arranged, and the building model 6, geogrid 22, and testing instruments were placed in the correct positions. The hydraulic output device was controlled to lift the structure by 10mm each time until it was lifted to 100mm, at which point the experiment ended. After the experiment, the results were quantitatively and qualitatively analyzed, specifically including the following steps:

[0114] Step 1: Debug the loading system used in the experiment. Place four wire displacement gauges 3 under the active plate of the displacement box 7 and connect them to the respective displacement signal receiving area of ​​the hydraulic control system 1 of the loading system. Operate the hydraulic control system 1 to lift vertically upward by 1mm for a preliminary experiment. Use a steel ruler to measure and verify whether the simulated bedrock “L”-shaped dislocation steel plate 4 has been lifted by 1mm. Observe whether the lifting distance of the simulated bedrock “L”-shaped dislocation steel plate 4 and the observed value are consistent. If they are inconsistent, the calibration parameters of the hydraulic control system 1 need to be adjusted. If they are consistent, proceed to the next step.

[0115] Step 2: Debugging of the data acquisition and analysis system 8 and sensors, including the soil pressure gauge 21, strain gauge, laser displacement gauge 5, and high-speed camera 10.

[0116] The earth pressure gauge 21 is debugged and connected to the data acquisition and analysis system 8. The earth pressure gauge 21 is calibrated using the water level method. The data display window of the data acquisition and analysis system 8 is used to observe whether the collected earth pressure measurement value and the calculated value are consistent. If they are inconsistent, the calibration parameters of the earth pressure gauge 21 need to be adjusted. If they are consistent, proceed to the next step.

[0117] Debug the laser displacement meter 5, connect the laser displacement meter 5 to the data acquisition and analysis system 8, fix the laser displacement meter 5 on the bracket and move it a fixed distance. Observe whether the acquired distance and the actual distance are consistent through the data display window of the data acquisition and analysis system 8. If they are inconsistent, the calibration parameters of the laser displacement meter 5 need to be adjusted. If they are consistent, proceed to the next step.

[0118] The high-speed camera 10 is debugged. After the high-speed camera 10 is connected to the data acquisition and analysis system 8, the high-speed camera 10 is placed directly in front of the test misalignment box 7. The camera range is adjusted until the entire test misalignment box 7 is within the field of view of the high-speed camera 10. The test misalignment box 7 is loaded, and high-speed photography is performed. The captured data is analyzed. If the data results do not meet the test requirements, the parameters of the high-speed camera 10 are adjusted. The above steps are repeated after adjustment until the captured data results meet the test requirements. If the test requirements are met, the next step is performed.

[0119] Step 3: Experimental model materials and processing include the preparation of the building model 6, the preparation of the geogrid 22 in the transverse reinforcement, and the preparation of the overburden soil. Preferably, the steel structure building model 6 in this invention adopts a six-story steel structure with a similarity ratio of 1:20 and a floor height of 15cm. Preferably, the reinforcement length of the geogrid 22 is the length of the projection of the main rupture trace on the surface of the overburden. In this invention, the length of the geogrid 22 is 1000mm and the width is 1730mm. When preparing the geogrid 22, 10 earth pressure gauges 21 are arranged at the location with the greatest influence on rupture development. Preferably, clay with a moisture content of 10% is used in this invention.

[0120] Step 4: When constructing a foundation with a height of 70cm or less, place 15cm of loose soil inside the sliding box 7, and use a tamping hammer to compact it starting from the leftmost side of the sliding box 7. Use the tamping hammer to compact the loose soil to 13cm for the first time.

[0121] Furthermore, the soil layer is compacted twice more using the same tamping method with a tamping hammer, compacting the soil layer to 10cm. After the soil is compacted, as follows... Figure 5 Earth pressure gauge 21 is installed at the junction of the two plates.

[0122] Further, the soil layer was compacted to 70cm using the method described above, and earth pressure gauges 21 were installed.

[0123] Step 5: When constructing a 70cm to 100cm foundation, lay a 15cm layer of loose soil on top of the simulated cover layer I zone 14. Use a square wooden stick to level the loose soil. Level the top of the soil by referring to the black standard line on the glass plate of the observation area of ​​the test misalignment box 7 (attach black standard lines at 5cm intervals in the test observation area of ​​the test misalignment box 7) following the principle of "more scraping and less patching".

[0124] Furthermore, the loose soil is lightly compacted for the first time with a small drop height using a tamping hammer, tamping the loose soil vertically downwards for 3cm. Then, the compacted soil is further compacted with a large drop height, tamping the soil vertically downwards for 2cm.

[0125] Furthermore, the compacted soil in the simulated overburden zone 14 was measured with a leveling rod, and the compacted soil was observed on the outside of the misaligned box 7. The compacted soil was observed to see if there were any protrusions or depressions, and the uneven soil was repaired until it was level.

[0126] Furthermore, the simulated overburden layer in area II 15 is compacted using the same method as that used in simulated overburden layer in area I 14.

[0127] Furthermore, the geogrid 22 is arranged in the geogrid arrangement area 16. Preferably, the longitudinal length of the bidirectional geogrid 22 is 1730mm and the latitudinal length is 1000mm. The small square of the geogrid 22 is 50mm×50mm. Before placing the geogrid 22, strain gauges are attached to the surface of the geogrid 22 at half the longitudinal direction and at 100mm intervals along the latitudinal direction and connected to the data monitoring and analysis system.

[0128] Furthermore, such as Figure 4 As shown, the geogrid 22 with strain gauges attached is placed in the geogrid arrangement area 16, with the two sides of the geogrid 22 35mm away from the glass plate of the observation area.

[0129] Furthermore, after the geogrid 22 is placed in the correct position, a 15cm high layer of loose soil is laid on the outside of the geogrid 22 to prevent it from moving when loose soil is placed in other areas of the geogrid 22. Then, a 15cm high layer of loose soil is placed in other areas of the geogrid 22. After the loose soil is laid, it is observed along the standard line in the observation area of ​​the misalignment box 7 to check for any uneven areas. Any uneven areas are repaired. After the loose soil is leveled, it is measured with a leveling rod until it is level.

[0130] Furthermore, after the surface of the loose soil is level, the soil is compacted in the same way as the compaction method of the simulated overburden layer I zone 14. After the soil is compacted, an earth pressure gauge 21 is placed at the junction of the two plates.

[0131] Furthermore, the geogrid 22 and earth pressure gauge 21 are installed at heights of 80cm and 90cm, and the installation method is the same as that at 70cm.

[0132] Step 6: After completing the overburden layer, dig a square trench 8cm deep and 50cm on each side directly above the junction of the upper and lower sections. Place the building model 6 in the trench, fill it with loose soil in layers, and compact it. After placing the building model 6, connect the strain gauges on the building model 6 to the data acquisition and analysis system 8.

[0133] Step 7: Arrange nine laser displacement gauges 5 at 40cm intervals on the horizontal bar above the covering layer and connect them to the data acquisition and analysis system 8. Arrange four wire displacement gauges 3 under the active plate of the displacement box 7 and connect them to the displacement signal receiving area of ​​the hydraulic control system 1. Start the data acquisition and analysis system 8, the high-speed camera 10, and the hydraulic control system 1.

[0134] Step 8: Operate the hydraulic control system 1 to lift vertically upward by 1mm, observe whether the data acquisition and analysis system 8 and the high-speed camera 10 are working properly, and complete the pre-experiment.

[0135] Step 9: Control the hydraulic control system 1 to lift vertically upward by 10mm, the data acquisition and analysis system 8 to collect data during the test, and the high-speed camera 10 to take pictures and record the test process, thus completing one test condition.

[0136] Step 10: Follow Step 9 until the test is completed by vertically lifting 100mm. It can be understood that before each test begins, the data acquisition and analysis system 8 will perform a zeroing operation on the monitoring data.

[0137] Step 11: Analyze the results of the data acquisition and analysis system 8 and the photos taken by the high-speed camera 10. Preferably, record whether the building foundation has obvious uneven deformation, whether the building has tilted, whether the foundation of the building's transverse reinforcement has been crossed by the crack trace, whether the strain change of the building's side column is greater than 50με, whether the strain change of the rightmost side of the geogrid at the top of the foundation is greater than 100με, and whether the soil pressure change at a height of 50cm in the overburden layer is greater than 5kPa. Fill the results into Table 1, the comprehensive evaluation table of the fracture resistance of the horizontal reinforcement, for statistical analysis.

[0138] It is understandable that: the test device and method for horizontally reinforced composite foundations resisting strong earthquake surface fractures provided in this example are simple to operate; the number of geogrid layers added to the overburden can be changed to study the ability of geogrids with different numbers of layers to resist the development of strong earthquake surface fracture zones; the type of reinforcement in the overburden can be changed to study the ability of horizontally reinforced structures made of different reinforcement materials to resist the development of strong earthquake surface fracture zones; the type of overburden can be changed to study the ability of transverse reinforcements under different overburden layers to resist strong earthquake surface fractures; compared with other test methods, this test adds buildings on the overburden and places strain gauges on the edge columns of the buildings, allowing observation of the influence of the reinforced composite foundation on the buildings on the overburden during the test; compared with other test methods, this test adds a comprehensive evaluation table of the fracture resistance of the horizontal reinforcement. After the test, quantitative and qualitative analysis indicators are filled into the evaluation table based on the data from the data acquisition and analysis system and the photos taken by the high-speed camera, providing a quantitative comparison of the ability of the horizontal reinforcement to resist the development of strong earthquake surface fracture zones, thus improving the accuracy of the test results.

[0139] The preferred embodiments of the present invention have been described in detail above. However, the present invention is not limited to the above embodiments. Within the scope of knowledge possessed by those skilled in the art, various changes can be made without departing from the spirit of the present invention.

[0140] Many other changes and modifications can be made without departing from the concept and scope of this invention. It should be understood that this invention is not limited to the specific embodiments, and the scope of this invention is defined by the appended claims.

Claims

1. A test device for a horizontal reinforcement composite foundation against strong ground surface rupture, characterized by, It comprises a test bedrock dislocation loading system, a data acquisition and analysis system (8) and sensors, and a building model (6); The test bedrock dislocation loading system comprises a hydraulic control system (1), four actuators (2), a dislocation box (7) and a wire displacement gauge (3); The hydraulic control system (1) comprises a hydraulic control panel, a displacement signal display panel, a hydraulic output area and a displacement signal receiving area; The dislocation box (7) comprises a front and back high-strength resin glass test observation area and left and right steel plates; the inside bottom of the box is provided with a simulated bedrock "L"-shaped dislocation steel plate (4) and a simulated bedrock static disc steel plate (9); a gap is left between the two plates for simulating a fracture zone; The dislocation box (7) is provided with a rammed soil cover; the simulated bedrock "L"-shaped dislocation steel plate (4) is provided with a simulated cover I area (14) above it, the simulated bedrock static disc steel plate (9) is provided with a simulated cover II area (15) above it, and the two areas are connected by a geogrid arrangement area (16); The geogrid arrangement area (16) is provided with a groove for placing a building foundation (13) at the bottom of the building model (6); the building foundation (13) is provided with a geogrid (22) below it; The four actuators (2) are arranged at the four corners of the simulated bedrock "L"-shaped dislocation steel plate (4); each actuator (2) is provided with a corresponding wire displacement gauge (3); the wire displacement gauge (3) is fixed to a support plate below the actuator (2) and the magnet head of the wire displacement gauge (3) is vertically upwardly attracted to the lower side of the "L"-shaped dislocation steel plate (4); The signal receiving wire of the wire displacement gauge (3) is connected to the respective displacement signal receiving area of the hydraulic control system (1); the actuator (2) is connected to the hydraulic output area of the hydraulic control system (1) by a hydraulic oil pipe; The sensors comprise a soil pressure gauge (21), a strain gauge, a laser displacement gauge (5) and a high-speed camera (10); the data acquisition and analysis system (8) is connected to each sensor; The high-speed camera (10) is placed in front of the dislocation box (7); A plurality of soil pressure gauges (21) are arranged above the joint of the two plates of the simulated bedrock "L"-shaped dislocation steel plate (4) and the simulated bedrock static disc steel plate (9) for monitoring the soil pressure increment change of the fracture trace in the process of the normal fault dislocation; the soil pressure gauges (21) are arranged in the area where the first fracture trace (19) and the second fracture trace (20) develop in the process of the normal fault dislocation; The strain gauges (17) of the geogrid are arranged on the geogrid (22) at intervals for analyzing the fracture resistance of the horizontal reinforcement composite foundation; The building edge column strain gauges (18) are arranged on the outside of the building edge column (11) of the building model (6) at a high level and at a high distance for monitoring the strain of the building edge column (11) in the process of the test and analyzing the fracture resistance of the horizontal reinforcement composite foundation; A plurality of laser displacement gauges (5) are arranged on the beam above the soil cover for analyzing the uneven deformation of the ground surface. The horizontal reinforcement composite foundation test method for resisting strong earthquake ground surface rupture comprises the following processes by using a horizontal reinforcement composite foundation test device for resisting strong earthquake ground surface rupture: The test bedrock dislocation loading system is debugged; The data acquisition and analysis system (8) and sensors are debugged; The test model material is prepared; The test model and sensors are arranged; The preparation work before the test and the test process are performed, the bedrock dislocation is gradually loaded, and multiple working condition tests are performed; Finally, the quantitative and qualitative analysis of the data results is performed, including the building inclination angle, the soil pressure increment in the covering layer, the geogrid strain increment, the building strain increment, and the building foundation deformation analysis; The test bedrock dislocation loading system debugging comprises the overall debugging of the hydraulic control system (1), the four actuators (2), the dislocation box body (7), and the wire displacement meter (3); The debugging method comprises: The wire displacement meter (3) is debugged, the first, second, third, and fourth wire displacement meters (3) are fixed at the support plate position below the actuator (2), the wire magnet head of the wire displacement meter (3) is vertically adsorbed on the lower side of the "L" type dislocation steel plate (4), and the verticality of the wire of the wire displacement meter (3) is measured and adjusted until the horizontal bubble is centered; The signal receiving line of the wire displacement meter (3) is connected to the displacement signal receiving area of the hydraulic control system (1), then the hydraulic control system (1) is started, and the wire of the wire displacement meter (3) is slowly pulled out by 1 cm, and whether the displacement signal of the hydraulic control display panel is 1 cm is observed, and the error is ±0.1%; The actuator (2) and the hydraulic output area of the hydraulic control system (1) are connected by a hydraulic oil pipe and the sealing property is checked; then, the lifting speed of 1 mm / s and the bedrock lifting amount of 10 mm are input on the hydraulic control panel, and the actuator (2) is lifted to the full stroke; then, the upper four corner positions of the "L" type dislocation steel plate (4) are measured by using a level, and whether the level bubble is centered is observed; The data acquisition and analysis system (8) and sensors are debugged, including the soil pressure gauge (21), the strain gauge, the laser displacement meter (5), and the high-speed camera (10); The soil pressure gauge (21) is debugged, including connecting the soil pressure gauge (21) to the data acquisition and analysis system (8), calibrating the soil pressure gauge (21) by using the water mark method, and observing whether the collected soil pressure and the calculated value are consistent through the data display window of the data acquisition and analysis system (8); The soil pressure gauge (21) is fixed at the 0 cm position of the end of the 1 m steel ruler with a scale, connected to the data acquisition and analysis system (8), and reset to zero, then placed at the positions of 10 cm, 50 cm, and 100 cm below the horizontal plane and kept still for 10 seconds, and whether the soil pressure in the data acquisition and analysis system (8) is within the range of ±5% of the actual value is observed and the soil pressure sensitivity parameter is adjusted. The debugging of the laser displacement meter (5) includes: numbering and sequentially connecting the plurality of laser displacement meters (5) to the data acquisition and analysis system (8), fixing the laser displacement meters (5) on the same side of the square steel beam with double-sided tape, and locating the laser emission area on the same side, placing a rectangular wood board 20 cm in front of the laser emission area of the laser displacement meter (5), and ensuring that the distance data of the laser displacement meter (5) in the data acquisition and analysis system (8) is 20 cm, translating the rectangular wood board 10 cm away from the laser displacement meter (5), and observing whether the data of the plurality of laser displacement meters (5) in the data acquisition and analysis system (8) is within ±5% of the actual value 30 cm; The debugging of the high-speed camera (10) includes: placing the high-speed camera (10) in front of the faulting box (7), adjusting the camera range until the entire test faulting box (7) is within the field of view of the high-speed camera (10), and analyzing the photographed soil body with fracture zone photos to observe whether the photographed test faulting box (7) photos are distorted, and adjusting the exposure and angle parameters of the high-speed camera (10); The test model and the arrangement of the sensors specifically include: The arrangement of the cover layer soil body includes: ramming a 100 cm soil cover layer in the faulting box (7); each time, 15 cm of virtual soil is placed, and a rammer is used to start ramming from the leftmost side of the faulting box (7); the virtual soil is rammed to 13 cm by the first ramming, then the soil layer is rammed to 12 cm by the second ramming, and the soil layer is rammed to 10 cm by the third ramming; after the soil layer is rammed to 70 cm according to the above method; after the corresponding position of the geogrid (22) is arranged as a horizontal reinforcing body in the 70 cm to 100 cm soil body, the soil layer is still rammed according to the above method; The arrangement of the geogrid (22) includes: arranging the geogrid (22) according to the building model (6) arranged at the most unfavorable position of the faulting as the center, arranging the geogrid (22) in the geogrid arrangement area (16), and after the strain gauges and connecting wires are arranged on the four corners and then pressed with virtual soil, a 15 cm high and 10 cm thick virtual soil is laid and rammed with a rammer, and a level is used for measurement and correction until it is level; The arrangement of the building model (6) includes: arranging the building model (6) at the most unfavorable position of the faulting, digging a 8 cm deep square soil groove in the vertical direction of the ground surface, placing the building foundation (13) of the building model (6) in the soil groove, and filling 9 cm of virtual soil to ram and scrape to the same height as the surface of the cover layer soil body; The arrangement of the soil pressure meter (21) includes: the soil pressure meter (21) is arranged in the area where the fracture trace develops during the bedrock dislocation of the normal fault, nine soil pressure meters (21) are arranged 10 cm apart above the junction of the two discs, and the soil pressure increment change of the fracture trace during the dislocation of the normal fault is monitored; The arrangement of the geogrid strain gauge (17) includes: arranging 10 strain gauges with a spacing of 10 cm in the middle of the geogrid (22) to analyze the anti-fracture capacity of the horizontal reinforcing body composite foundation. The building side column strain gauge (18) arrangement comprises: arranging three-way strain gauges on the outer side of the building side column (11) at layer height intervals to monitor the strain of the building side column (11) during the test, so as to analyze the anti-fracture capacity of the horizontal reinforcement composite foundation; The arrangement of the laser displacement meter (5) comprises: arranging a plurality of laser displacement meters (5) on the crossbeam 20 cm above the covering layer from the right side of the displacement box (7) to the inner side of the steel plate at intervals of 40 cm, so as to analyze the uneven deformation of the ground surface; The gradual loading of the bedrock displacement is carried out, and multiple working condition tests are carried out, including: Starting the data acquisition and analysis system (8) to collect test data; starting the hydraulic control system (1), synchronously jacking 1mm, observing whether the sensor reading is normal; respectively carrying out 10 working conditions, each time the line displacement meter (3) gives 10mm bedrock displacement input, and before each test, the data acquisition is cleared to zero; The quantitative and qualitative analysis of the data results comprises: building inclination angle, covering layer soil pressure increment analysis, geogrid strain increment analysis of each layer, i.e. whether the geogrid strain close to the building changes significantly, building strain increment analysis, whether the building foundation passes through the fracture zone, and whether the building foundation produces obvious uneven deformation, i.e. whether a stepped scarp is produced.

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