Roadbed filler performance indoor detection test method

Abstract

The invention relates to the technical field of roadbed filler detection, in particular to a roadbed filler performance indoor detection test method which comprises the following steps: paving a roadbed filler sample on a detection platform for pretreatment; pressurizing the initial-state roadbed filler sample to obtain a stable roadbed filler sample, and recording the pressure change and the surface height change of each layer; evaluating whether the roadbed filler reaches a deformation standard or not according to a detection result; adding equal volume of water into the initial-state roadbed filler sample and the stable-state roadbed filler sample, measuring and recording the water immersion height, judging whether the roadbed filler sample meets the stability standard or not, carrying out simulated filling on the initial-state roadbed filler, carrying out pressurized deformation detection by using a second deformation pressure group, and determining the performance grade of the filler; the second deformation pressure is repeatedly used for detecting the simulated roadbed filler, the filler performance grade is adjusted according to the final deformation quantity, the pressure resistance and deformation characteristics of the filler can be accurately evaluated, and it is ensured that the filler meets the requirements of highways of different grades.

Description

Technical Field

[0001] The invention relates to the technical field of roadbed filler detection, and in particular to an indoor detection test method for roadbed filler performance. Background Art

[0002] Methods for testing roadbed fillers usually involve on-site compaction tests and indoor geotechnical tests, such as penetration tests, Beckman beam tests, and nuclear density meters. These methods can evaluate the compaction and uniformity of fillers, but they often cannot fully simulate the impact of actual traffic loads on roadbed fillers, and lack evaluation of the long-term stability and durability of fillers. In addition, traditional testing methods may have problems such as complex operations, low efficiency, or inaccurate results, which limits their application in evaluating roadbed filler performance.

[0003] Chinese patent publication number: CN106093346B, discloses a method for evaluating the filling quality of soft rock embankments, the steps are: 1. Take a representative soft rock sample before roadbed filling, and conduct 0, 1, 3, and 5 dry-wet cycle tests on it in sequence, and conduct a screening test on it after each dry-wet cycle test to obtain the corresponding particle component dimension; 2. Detect the last two compaction settlement differences of the roadbed; 3. Conduct a screening test on the soft rock sample after on-site compaction to determine its particle component dimension; 4. According to the test results of step 2, combined with the comparison results of the particle component dimensions obtained in steps 1 and 3, conduct a comprehensive evaluation of the filling quality of the soft rock embankment; It can be seen that the method for evaluating the filling quality of the soft rock embankment has the following problems: It does not take into account that when filling different types of roads, the standards for filler performance are different, resulting in inaccurate evaluation results, affecting the subsequent construction quality. Summary of the invention

[0004] To this end, the present invention provides an indoor testing method for roadbed filler performance, which is used to overcome the problem that the prior art does not consider different standards for filler performance when filling different types of roads, resulting in inaccurate evaluation results and affecting the subsequent construction quality.

[0005] To achieve the above object, the present invention provides a method for indoor detection of roadbed filler performance, comprising: Sampling the roadbed filler to be tested, laying the roadbed filler samples on several testing platforms, and performing preliminary leveling on each of them to obtain several initial roadbed fillers, and testing the height of the initial roadbed fillers; Use the first deformation pressure to perform a pressurized stability test on the initial state roadbed filler to obtain a stable roadbed filler sample, record the pressure changes of each layer of the initial state roadbed filler and the surface height changes, and determine whether the roadbed filler to be tested meets the filler deformation standard according to the pressurized stability test result; Adding the same volume of water to a sample of the initial roadbed filler and the stabilized roadbed filler, respectively detecting the water immersion height of the corresponding detection platform, and recording the detection results; Judging whether the roadbed filler to be tested meets the filler stability standard according to the test result of the water immersion height; Perform simulated filling on several of the initial-state roadbed fillers to obtain simulated roadbed fillers, use the second deformation pressure group to perform pressurized deformation detection on each simulated roadbed filler, and determine the performance level of the initial roadbed filler according to the detection result; repeatedly use the pressure corresponding to the second deformation pressure group to perform simulated deformation detection on each of the simulated roadbed fillers, and determine whether to adjust the performance level of the initial roadbed filler according to the simulation results.

[0006] Furthermore, the pressurized stability test on the initial roadbed filler includes: Using a first deformation pressure to pressurize the initial state roadbed filler; Detecting and recording the pressure change at the midpoint of the initial roadbed filler and the bottom of the initial roadbed filler; After the pressurization is completed, the height change of the initial roadbed filling material is detected and recorded.

[0007] Further, determining whether the roadbed filler to be tested meets the filler deformation standard according to the pressurized stability test result includes: If the surface height change is less than the standard surface height change, and the pressure of each layer is within the corresponding change threshold range, it is determined that the roadbed filler to be tested meets the filler deformation standard.

[0008] Furthermore, the height of the same volume of water added to a sample of the initial state roadbed filler and the stabilized roadbed filler is lower than the height of the initial state roadbed filler, and the water immersion height is higher than the midpoint of the initial state roadbed filler.

[0009] Further, judging whether the roadbed filler to be tested meets the filler stability standard according to the detection result of the water immersion height includes: Calculate the height difference between the water immersion height of the initial state roadbed filling material and the water immersion height of the stable roadbed filling material sample; If the height difference is greater than the water immersion height difference threshold, it is determined that the roadbed filler to be tested does not meet the filler stability standard.

[0010] Further, using the second deformation pressure group to perform the pressurized deformation detection on each of the simulated roadbed fillers includes: The simulated roadbed filler is pressurized using level I load pressure, level II load pressure, and level III load pressure respectively; When the height of each simulated roadbed filler no longer changes, the height change of each simulated roadbed filler is determined respectively and recorded as the pressure deformation detection result; Wherein, the second deformation pressure group includes the level I load pressure, the level II load pressure and the level III load pressure.

[0011] Furthermore, the performance grade of the initial roadbed filler is determined in combination with the pressurized deformation results of each simulated roadbed filler, including: If the pressurized deformation result meets the first load condition, the initial roadbed filler grade is determined to be a first-class roadbed filler; If the pressurized deformation result meets the second load condition, the initial roadbed filler grade is determined to be a secondary roadbed filler; If the pressurized deformation result meets the third load condition, it is determined that the initial roadbed filler grade is a third-grade roadbed filler.

[0012] Furthermore, the first load condition is that the deformation amount corresponding to the level I load pressure is smaller than the level I deformation amount; The second load condition is that the deformation amount corresponding to the level I load pressure is greater than or equal to the level I deformation amount, and the deformation amount corresponding to the level II load pressure is less than the level II deformation amount; The third load condition is that the deformation corresponding to the level I load pressure is greater than or equal to the level I deformation, the deformation corresponding to the level II load pressure is greater than or equal to the level II deformation, and the deformation corresponding to the level III load pressure is less than the level III deformation.

[0013] Further, repeatedly using the pressure in the corresponding second deformation pressure group to perform simulated deformation detection on the simulated roadbed filler includes: Obtaining the performance grade of the initial roadbed filler, and determining the corresponding second deformation pressure and the preset number of simulations; The simulated roadbed filler is repeatedly pressurized using the corresponding second deformation pressure according to a preset number of simulations, and the final deformation amount is recorded.

[0014] Further, determining whether to adjust the initial roadbed filler performance level according to the simulation result includes: If the final deformation amount meets the corresponding load condition, it is determined that the initial roadbed filler performance level is not adjusted, and is recorded as the performance level of the roadbed filler to be tested; If the final deformation amount does not meet the corresponding load condition, it is determined to adjust the performance level of the initial roadbed filling material.

[0015] Compared with the prior art, the beneficial effect of the present invention is that the indoor testing method for roadbed filler performance provided by the present invention can accurately evaluate the pressure resistance and deformation characteristics of the filler by simulating actual traffic loads to perform pressure deformation testing on the filler, ensuring that the filler meets the requirements of different grades of highways. This method characterizes the performance changes of the roadbed under long-term traffic loads through repeated pressure simulations, effectively tests the performance stability of the filler under repeated loads, improves the economy and applicability of road construction, ensures the safety of high-speed vehicles, reduces maintenance costs, extends the service life of roads, and provides a scientific decision-making basis for road design and construction.

[0016] Furthermore, by simulating the pressurization conditions that fillers may encounter in actual road construction, the reliability of the test results and the relevance to practical applications are ensured. This helps determine the deformation and stability of fillers under different pressures, providing a scientific basis for roadbed design and construction.

[0017] Furthermore, by detecting the deformation of the roadbed filler, the uniformity and integrity of the roadbed can be ensured, road damage caused by uneven settlement can be avoided, and the stability of the road structure can be ensured. Secondly, by setting the pressure change of the middle layer and the bottom within a specific range, the stability and bearing capacity of the filler under pressure can be evaluated. The roadbed with high bearing capacity can better support the upper structure, reduce deformation caused by traffic loads, and extend the service life of the road. By detecting whether the pressure change exceeds the change range, the stability of the filler particles can be identified, and problems that may affect the performance of the roadbed can be discovered in time, thereby providing a more accurate scientific basis for roadbed design and construction.

[0018] Furthermore, the stability of the roadbed filler is judged by the test results of the water immersion height. By comparing the water immersion height difference between the initial roadbed filler and the stabilized roadbed filler sample, the particle crushing of the filler after being subjected to pressure can be evaluated, thereby judging whether the filler meets the stability standard. If the water immersion height difference is greater than the set threshold, the filler is considered unstable and does not meet the standard.

[0019] Furthermore, by simulating the load pressure of different grades of highways, the pressure resistance and deformation characteristics of the filler are accurately evaluated to ensure that the filler can meet the requirements of different grades of highways. This method not only improves the economy and applicability of road construction, but also ensures the safety of high-speed vehicles, while reducing maintenance costs, extending the service life of the road, and providing a scientific decision-making basis for road design and construction.

[0020] Furthermore, by simulating actual traffic loads, different grades of roadbed fillers are repeatedly pressure tested to evaluate their stability and durability under long-term loads. Based on the test results, it can be determined whether the filler meets the requirements of a specific highway grade, and the performance grade of the filler can be adjusted accordingly to ensure that the appropriate filler is used in road construction, improve road quality and reduce maintenance costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 It is a flow chart of the indoor testing method for roadbed filler performance according to an embodiment of the present invention; Figure 2 This is a flow chart of performing pressurization stability detection on an initial state roadbed filler according to an embodiment of the present invention; Figure 3 A logic diagram for judging whether a roadbed filler to be tested meets a filler stability standard according to an embodiment of the present invention; Figure 4 A logic diagram for determining whether to adjust the initial roadbed fill material performance level according to an embodiment of the present invention. DETAILED DESCRIPTION

[0022] In order to make the objects and advantages of the present invention more clearly understood, the present invention is further described below in conjunction with embodiments; it should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0023] The preferred embodiments of the present invention are described below with reference to the accompanying drawings. It should be understood by those skilled in the art that these embodiments are only used to explain the technical principles of the present invention and are not intended to limit the protection scope of the present invention.

[0024] It should be noted that, in the description of the present invention, terms such as "up", "down", "left", "right", "inside" and "outside" indicating directions or positional relationships are based on the directions or positional relationships shown in the drawings. This is merely for the convenience of description and does not indicate or imply that the device or element must have a specific orientation, be constructed and operated in a specific orientation. Therefore, it cannot be understood as a limitation on the present invention.

[0025] See also Figure 1 As shown, it is a flow chart of an indoor testing method for roadbed filler performance according to an embodiment of the present invention; an indoor testing method for roadbed filler performance comprises: Step S1, sampling the roadbed filler to be tested, laying the roadbed filler samples on several testing platforms, and performing preliminary leveling on each of them to obtain several initial state roadbed fillers, and testing the height of the initial state roadbed fillers; Step S2, using the first deformation pressure to perform a pressurized stability test on the initial state roadbed filler to obtain a stable roadbed filler sample, recording the pressure changes of each layer of the initial state roadbed filler and the surface height changes, and determining whether the roadbed filler to be tested meets the filler deformation standard according to the pressurized stability test result; Step S3, adding the same volume of water to a sample of the initial roadbed filler and the sample of the stabilized roadbed filler, respectively detecting the water immersion height of the corresponding detection platform, and recording the detection results; Step S4, judging whether the roadbed filler to be tested meets the filler stability standard according to the detection result of the water immersion height; Step S5, simulate the filling of several of the initial state roadbed fillers to obtain simulated roadbed fillers, use the second deformation pressure group to perform pressurized deformation detection on each simulated roadbed filler, and determine the performance level of the initial roadbed filler according to the detection result; repeatedly use the pressure corresponding to the second deformation pressure group to perform simulated deformation detection on each of the simulated roadbed fillers, and determine whether to adjust the performance level of the initial roadbed filler according to the simulation results.

[0026] In implementation, the detection platform is a square box with five closed sides, and the maximum pressure that the square box can withstand is greater than the pressure exerted by the vehicle on the road surface. It is a rigid container, the height of the square box is 30 to 40 centimeters, and the height of all initial roadbed fillings is 30 cm.

[0027] When initially leveling the roadbed filler sample, first vibrate the detection platform to change the distribution position of large and small particles in the roadbed filler sample and reduce the gaps in the sample. After the vibration, place a load plate with an area slightly smaller than the square box on the top of the sample and apply pressure of 5 kPa perpendicular to the horizontal plane until the position of the load plate no longer changes and the load plate is parallel to the horizontal plane.

[0028] In the above embodiments, the pressurization method and the pressure detection method are both existing technologies, and the implementation method is not specifically limited. The pressurization process is to start from 0 and pressurize at a uniform speed.

[0029] The present invention provides an indoor testing method for the performance of roadbed fillers, which can accurately evaluate the pressure resistance and deformation characteristics of the fillers by simulating actual traffic loads to perform pressure deformation testing on the fillers, and ensure that the fillers meet the requirements of different grades of highways. This method characterizes the performance changes of the roadbed under long-term traffic loads through repeated pressure simulations, effectively tests the performance stability of the fillers under repeated loads, improves the economy and applicability of road construction, ensures the safety of high-speed vehicles, reduces maintenance costs, prolongs the service life of roads, and provides a scientific decision-making basis for road design and construction.

[0030] See also Figure 2As shown, it is a flow chart of the pressurization stability detection of the initial state roadbed filler according to an embodiment of the present invention. The pressurization stability detection of the initial state roadbed filler includes: Using a first deformation pressure to pressurize the initial state roadbed filler; Detecting and recording the pressure change at the midpoint of the initial roadbed filler and the bottom of the initial roadbed filler; After the pressurization is completed, the height change of the initial roadbed filling material is detected and recorded.

[0031] In implementation, the first deformation pressure is 20 kPa, and the pressurization movement rate is 0.5 to 1 mm / min. It can be understood that if the pressurization movement rate is faster, the material will not have time to fully deform and adjust, and the measured deformation may be smaller; on the contrary, if the pressurization movement rate is too slow, the deformation of the material will be too large. Therefore, selecting a pressurization movement rate of 0.5 to 1 mm / min can make the pressurization stability detection more in line with actual requirements.

[0032] It is understandable that if the packing is an ideal rigid body that will not deform at all, according to Pascal's law, in a closed static fluid (or a solid with a small diameter in this case, it can be compared), the pressure applied to the static liquid (or rigid body) is transmitted in all directions without changing in magnitude. When a constant pressure is applied to the surface of this ideal non-deformable packing, the pressure in the shallow layer (close to the surface) will not change in theory. Because the absence of deformation means that the relative position and contact state between the particles will not change, the pressure will be evenly transmitted inside the packing, and the pressure on the shallow layer is the same as the applied pressure, and it remains constant at all points.

[0033] In the present invention, by simulating the pressurization conditions that fillers may encounter in actual road construction, the reliability of the test results and the relevance to practical applications are ensured, which helps to determine the deformation and stability of fillers under different pressures and provide a scientific basis for roadbed design and construction.

[0034] Specifically, determining whether the roadbed filler to be tested meets the filler deformation standard according to the pressurized stability test result includes: If the surface height change is less than the standard surface height change, and the pressure of each layer is within the corresponding change threshold range, it is determined that the roadbed filler to be tested meets the filler deformation standard.

[0035] In implementation, the standard surface height change is 1% to 2%. If the deformation of the roadbed filler is too large, it will affect the stability of the road structure. A smaller deformation helps to maintain the uniformity and integrity of the roadbed and reduce road damage caused by uneven settlement. In addition, too large a deformation may cause uneven settlement of the roadbed, which is not conducive to the long-term use and maintenance of the road. A small deformation means that the compaction degree of the filler is higher, indicating that the roadbed has a high bearing capacity. A high-bearing-capacity roadbed can better support the superstructure and reduce deformation caused by traffic loads, thereby extending the service life of the road.

[0036] The pressure change at the midpoint is selected in the interval [1kPa, 2kPa], and the pressure change at the bottom is selected in the interval [2kPa, 4kPa]. Ideally, the roadbed filler is a homogeneous, isotropic elastic material, and the pressure is evenly distributed. According to the basic principles of elastic mechanics, the pressure decreases linearly during the vertical pressure transmission process. For a 30cm thick filler, a 20kPa pressure is applied to the surface, and the pressure in the middle layer is 10kPa after stabilization. Based on the linear stress distribution model, the internal pressure is distributed proportionally.

[0037] In addition, considering the influence of actual filler characteristics, for coarse-grained fillers, since the particles are mainly in point contact and friction, after the pressure stabilizes, the pressure in the middle layer depends on the grading and arrangement of the particles. If the particle grading is good and a stable skeleton structure is formed, the pressure is mainly transmitted through the particle skeleton. At this time, there are constraints around the filler, and the diffusion of pressure in the horizontal direction is limited, which will make the middle layer pressure relatively high. In this case, the stable middle layer pressure is between 11 and 12 kPa.

[0038] In actual situations, if the roadbed filler particles are unstable, they are prone to further breakage after being subjected to pressure. At this time, the pressure on the bottom and the middle will be less than the standard situation, that is, it will exceed the variation range.

[0039] In the present invention, by detecting the deformation of the roadbed filler, the uniformity and integrity of the roadbed are ensured, road surface damage caused by uneven settlement is avoided, and the stability of the road structure is ensured. Secondly, by setting the pressure change of the middle layer and the bottom within a specific range, the stability and bearing capacity of the filler under pressure can be evaluated. The roadbed with high bearing capacity can better support the upper structure, reduce deformation caused by traffic load, and extend the service life of the road. By detecting whether the pressure change exceeds the change range, the stability of the filler particles can be identified, and problems that may affect the performance of the roadbed can be discovered in time, thereby providing a more accurate scientific basis for roadbed design and construction.

[0040] Specifically, the height of the same volume of water added to a sample of the initial state roadbed filling material and the stabilized roadbed filling material is lower than the height of the initial state roadbed filling material, and the water immersion height is higher than the midpoint of the initial state roadbed filling material.

[0041] It is understandable that if the roadbed material is subjected to pressure, the particles therein will be broken to produce even finer particles to fill the gaps, and the even finer particles will fall to the lower part of the detection platform. this This results in more solid volume in the lower layer and less water being able to penetrate.

[0042] See also Figure 3 As shown, it is a logic diagram of judging whether the roadbed filler to be detected meets the filler stability standard according to an embodiment of the present invention. Judging whether the roadbed filler to be detected meets the filler stability standard according to the detection result of the water immersion height includes: Calculate the height difference between the water immersion height of the initial state roadbed filling material and the water immersion height of the stable roadbed filling material sample; If the height difference is greater than the water immersion height difference threshold, it is determined that the roadbed filler to be tested does not meet the filler stability standard.

[0043] In practice, the threshold of water flooding height difference is 5% of the water flooding height of the initial roadbed filler. It is understandable that rural roads have lighter traffic loads and slower vehicle speeds, and are more tolerant of filler fragmentation. Under the design pressure, filler fragmentation is generally allowed as long as it does not cause large potholes or serious deformation on the road surface. Measured by height change (filler is pressure tested in a certain container), it is acceptable for the filler layer height to increase by no more than 5% of the original height of the filler layer due to fragmentation. This amount of fragmentation can ensure the basic traffic needs of rural vehicles.

[0044] In the present invention, the stability of the roadbed filler is judged by the detection result of the water immersion height. By comparing the water immersion height difference between the initial state roadbed filler and the stable roadbed filler sample, the particle crushing of the filler after being subjected to pressure can be evaluated, thereby judging whether the filler meets the stability standard. If the water immersion height difference is greater than the set threshold, the filler is considered unstable and does not meet the standard.

[0045] This method is particularly suitable for rural roads because rural roads have a higher tolerance for filler breakage. As long as the breakage of the filler does not cause large potholes or serious deformation of the road surface, it can generally meet basic traffic needs.

[0046] Specifically, using the second deformation pressure group to perform the pressurized deformation detection on each of the simulated roadbed fillers includes: The simulated roadbed filler is pressurized using level I load pressure, level II load pressure, and level III load pressure respectively; When the height of each simulated roadbed filler no longer changes, the height change of each simulated roadbed filler is determined respectively and recorded as the pressure deformation detection result; Wherein, the second deformation pressure group includes the level I load pressure, the level II load pressure and the level III load pressure.

[0047] In practice, the level I load pressure is 100-120 kPa, the level II load pressure is 40-60 kPa, and the level III load pressure is 25-30 kPa.

[0048] Each load pressure acts on different initial roadbed filling materials to avoid repeated pressurization affecting the test results. The number of simulated roadbed filling materials selected is a multiple of 3.

[0049] Specifically, the performance grade of the initial roadbed filler is determined in combination with the pressure deformation results of each simulated roadbed filler, including: If the pressurized deformation result meets the first load condition, the initial roadbed filler grade is determined to be a first-class roadbed filler; If the pressurized deformation result meets the second load condition, the initial roadbed filler grade is determined to be a secondary roadbed filler; If the pressurized deformation result meets the third load condition, it is determined that the initial roadbed filler grade is a third-grade roadbed filler.

[0050] In implementation, the first-level roadbed filling corresponds to the highway-I level load standard and can be used for expressways and first-level highways. The second-level roadbed filling corresponds to the highway-II level load standard and can be used for second-level highways. The third-level roadbed filling is lower than the highway-II level load standard and can be used for rural roads.

[0051] The design of expressways usually adopts the highway-I level load standard. Taking a double-axle double-wheel set as an example, its standard axle load is 100kN (about 10.2 tons). After considering factors such as vehicle dynamic impact, the actual pressure on the road surface and roadbed will be greater. According to the pavement structure mechanics calculation model, for example, the pavement structure thickness is 70cm (including surface layer, base layer, etc.), the elastic modulus of the roadbed filler is 40MPa, and through the multi-layer elastic system theory calculation, under the standard axle load, the pressure on the top of the roadbed is about 60~80kPa. In addition, the traffic volume on the expressway is large, and vehicles pass frequently. This pressure will act repeatedly, requiring the roadbed filler to be able to withstand such pressure for a long time without excessive deformation. In addition, for areas such as toll stations and service areas where vehicles frequently brake and start, the force exerted by the vehicle on the road surface will produce a large pressure pulse in a short time. For example, in the toll station lane, the braking force of the vehicle when braking will instantly increase the axle load by 30%~50%, so this part of the roadbed filler in these areas must withstand a pressure of 100~120kPa.

[0052] Secondary roads generally adopt the highway-II load standard, and the standard axle load of the double-axle double-wheel group is a certain proportion of 100kN (such as about 80%), that is, about 80kN (about 8.2 tons). For example, the pavement structure thickness is 60cm, and the elastic modulus of the roadbed filler is 30MPa. After calculation, the pressure on the top surface of the roadbed is about 40-60kPa. Compared with expressways, the pressure requirement is reduced, mainly because the traffic flow and vehicle load on secondary roads are relatively small, and the requirements for the pressure resistance of the roadbed filler are also reduced accordingly.

[0053] Rural roads mainly serve small vehicles and agricultural machinery in rural areas. The vehicle load is relatively light, and the design load is generally based on the common vehicle types and maximum axle weight in the local area. For example, the single axle weight of a small agricultural vehicle commonly used in rural areas may be around 3 to 5 tons. For example, if the thickness is 30 to 40 cm and the elastic modulus of the roadbed filler is 20 MPa, the calculated pressure on the top surface of the roadbed is 20 to 30 kPa. Since the traffic volume on rural roads is small and the vehicle load is light, the pressure resistance requirements for the roadbed filler are relatively low, mainly to ensure that the roadbed can maintain basic stability under limited traffic loads and avoid obvious deformation and damage.

[0054] Specifically, the first load condition is that the deformation corresponding to the level I load pressure is less than the level I deformation; The second load condition is that the deformation amount corresponding to the level I load pressure is greater than or equal to the level I deformation amount, and the deformation amount corresponding to the level II load pressure is less than the level II deformation amount; The third load condition is that the deformation corresponding to the level I load pressure is greater than or equal to the level I deformation, the deformation corresponding to the level II load pressure is greater than or equal to the level II deformation, and the deformation corresponding to the level III load pressure is less than the level III deformation.

[0055] In practice, the deformation of level I is 0.5% to 1%, the deformation of level II is 1% to 2%, and the deformation of level III is 2% to 3%. It is understandable that the speed of vehicles on highways is high and vehicles are very sensitive to the smoothness of the road surface. Even a small deformation of the roadbed may cause a chain reaction in the pavement structure. If the coarse-grained soil filler deforms too much, it will cause the road surface to become uneven, which will cause bumps and vibrations when the vehicle is driving. When the vertical deformation exceeds 1% of the height of the filler layer, the road surface may have slight undulations, affecting the comfort and safety of high-speed vehicles. In the long run, it may also cause damage to the pavement structure and the risk of cracks.

[0056] For secondary roads, a certain amount of deformation is allowed in consideration of the economy and feasibility of the actual project. Within this deformation range, the basic flatness of the road surface can be guaranteed to meet the driving requirements of vehicles on secondary roads, and excessive engineering costs will not be increased due to excessive restrictions on deformation, such as excessive compaction. In addition, the requirements for road surface flatness on secondary roads are lower than those on expressways. Controlling the vertical deformation within the range of 1% to 2% of the height of the filler layer can meet the normal passage of vehicles while avoiding serious road surface damage caused by excessive deformation, which affects the normal use of the road.

[0057] For rural roads, these roads mainly serve rural areas or areas with low traffic volume, where vehicle speeds are relatively slow and the requirements for road surface flatness are relatively low. Therefore, under the premise of ensuring the basic stability of the roadbed, appropriately relaxing the deformation requirements of coarse-grained soil fillers can reduce engineering costs while meeting local traffic needs. In actual situations, considering the occasional passage of heavy agricultural machinery, the deformation amount needs to be controlled within a range, but in general, the deformation range is lower than the standards of expressways, first-class highways, and second-class highways, and can meet the basic traffic requirements of third-class highways and below.

[0058] In the present invention, by simulating the load pressure of highways of different grades, the pressure resistance and deformation characteristics of the filler are accurately evaluated to ensure that the filler can meet the requirements of highways of different grades. This method not only improves the economy and applicability of road construction, but also ensures the safety of high-speed vehicles, while reducing maintenance costs, extending the service life of the road, and providing a scientific decision-making basis for road design and construction.

[0059] See also Figure 4 As shown, it is a logic diagram of determining whether to adjust the performance level of the initial roadbed filler according to an embodiment of the present invention, and repeatedly using the pressure in the corresponding second deformation pressure group to perform simulated deformation detection on the simulated roadbed filler, including: Obtaining the performance grade of the initial roadbed filler, and determining the corresponding second deformation pressure and the preset number of simulations; The simulated roadbed filler is repeatedly pressurized using the corresponding second deformation pressure according to a preset number of simulations, and the final deformation amount is recorded.

[0060] In practice, the preset simulation times of the primary roadbed filling material is 10 to 15 times, the preset simulation times of the secondary roadbed filling material is 6 to 10 times, and the simulation times of the tertiary roadbed filling material is 2 to 3 times. The final deformation amount is the simulation result.

[0061] Highways have large traffic volumes and vehicles pass through frequently. Within the design life, a lane will be subjected to millions of vehicle loads. Through 10 to 15 pressurization simulations, the performance changes of the roadbed under long-term traffic loads can be approximately reflected to a certain extent. For example, each pressurization is equivalent to the cumulative effect of vehicle axle loads after a certain number of times, so that the deformation accumulation and strength attenuation of the filler after repeated pressure can be observed. Highways have extremely high requirements for the durability of the roadbed. Multiple pressurization tests can better test whether the filler will have problems such as excessive deformation, particle crushing, and structural damage under repeated loads. If the filler can still maintain stable performance after 10 to 15 pressurizations, that is, the deformation is within the allowable range, it can be determined that the long-term stability of the roadbed can be guaranteed in actual highway use, reducing the cost of later repairs and maintenance.

[0062] The traffic volume of secondary roads is relatively small compared to that of expressways, and the frequency of vehicles passing through is low. 6 to 10 pressurizations can simulate the vehicle load conditions of secondary roads over a long period of time (such as within the design service life). For example, considering the number of lanes, daily traffic volume, and vehicle types of secondary roads, such a number of pressurizations can reasonably evaluate the performance of the filler under actual traffic loads. Compared with expressways, secondary roads have slightly lower requirements for roadbed performance. 6 to 10 pressurization tests can effectively detect whether the filler meets the basic use requirements of secondary roads, ensure flatness and load-bearing capacity, and will not increase unnecessary costs due to too many tests. At the same time, through this number of tests, the main problems that may occur in the filler under repeated loads can be observed, such as whether deformation will gradually accumulate to the extent that it affects the normal use of the road.

[0063] Class III highways and roads below mainly serve areas with low traffic volume and light vehicle loads. In actual use, the number of vehicle loads on the roads is relatively small. 3 to 5 pressurization times can simulate the main load conditions of such roads during their service life. For example, rural roads are mainly used by agricultural vehicles and a small number of small cars, and the frequency of load action is low. 3 to 5 pressurizations can reflect the performance of the roadbed filler under the long-term action of these vehicles. In addition, the requirements for the roadbed of such roads are mainly to ensure basic traffic functions. Through 3 to 5 pressurization tests, it can be detected whether the filler will be significantly deformed or damaged under the action of load, so as to determine whether it can meet the normal traffic needs of local vehicles. For Class III highways and roads below, too many tests may require excessive filler performance, increase engineering costs and not meet actual needs.

[0064] Specifically, determining whether to adjust the initial roadbed filler performance level according to the simulation results includes: If the final deformation amount meets the corresponding load condition, it is determined that the initial roadbed filler performance level is not adjusted, and is recorded as the performance level of the roadbed filler to be tested; If the final deformation amount does not meet the corresponding load condition, it is determined to adjust the performance level of the initial roadbed filling material.

[0065] During implementation, if the initial roadbed filling grade is a first-level roadbed filling, it is determined to be adjusted to a second-level roadbed filling when adjusting the performance grade of the initial roadbed filling; if the initial roadbed filling grade is a second-level roadbed filling, it is determined to be adjusted to a third-level roadbed filling when adjusting the performance grade of the initial roadbed filling; if the initial roadbed filling grade is a third-level roadbed filling, the roadbed filling to be tested is determined to be unqualified.

[0066] In the present invention, by simulating actual traffic loads, different grades of roadbed fillers are repeatedly pressurized to evaluate their stability and durability under long-term loads. Based on the test results, it can be determined whether the filler meets the requirements of a specific highway grade, and the performance grade of the filler can be adjusted accordingly to ensure that the appropriate filler is used in road construction, improve road quality and reduce maintenance costs.

[0067] If the indoor testing method for roadbed filler performance of the present invention is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present invention, in essence, or the part that contributes to the prior art, or all or part of the technical solution can be embodied in the form of a software product. The computer software product is stored in a storage medium, including several instructions for a computer device (which can be a personal computer, server, or network device, etc.) to perform all or part of the steps of the method described in each embodiment of the present invention. The aforementioned storage medium includes: U disk, mobile hard disk, read-only memory (ROM, Read-Only Memory), random access memory (RAM, Random Access Memory), disk or optical disk, etc. Various media that can store program codes.

[0068] So far, the technical solutions of the present invention have been described in conjunction with the preferred embodiments shown in the accompanying drawings. However, it is easy for those skilled in the art to understand that the protection scope of the present invention is obviously not limited to these specific embodiments. Without departing from the principle of the present invention, those skilled in the art can make equivalent changes or substitutions to the relevant technical features, and the technical solutions after these changes or substitutions will fall within the protection scope of the present invention.

[0069] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A method for indoor detection of roadbed filler performance, characterized in that: include: Sampling the roadbed filler to be tested, laying the roadbed filler samples on several testing platforms, and performing preliminary leveling on each of them to obtain several initial roadbed fillers, and testing the height of the initial roadbed fillers; Use the first deformation pressure to perform a pressurized stability test on the initial state roadbed filler to obtain a stable roadbed filler sample, record the pressure changes of each layer of the initial state roadbed filler and the surface height changes, and determine whether the roadbed filler to be tested meets the filler deformation standard according to the pressurized stability test result; Adding the same volume of water to a sample of the initial roadbed filler and the stabilized roadbed filler, respectively detecting the water immersion height of the corresponding detection platform, and recording the detection results; Judging whether the roadbed filler to be tested meets the filler stability standard according to the test result of the water immersion height; Perform simulated filling on several of the initial-state roadbed fillers to obtain simulated roadbed fillers, use the second deformation pressure group to perform pressurized deformation detection on each simulated roadbed filler, and determine the performance level of the initial roadbed filler according to the detection result; repeatedly use the pressure corresponding to the second deformation pressure group to perform simulated deformation detection on each of the simulated roadbed fillers, and determine whether to adjust the performance level of the initial roadbed filler according to the simulation results.

2. The indoor testing method for roadbed filler performance according to claim 1 is characterized in that: The pressurized stability test of the initial roadbed filler includes: Using a first deformation pressure to pressurize the initial state roadbed filler; Detecting and recording the pressure change at the midpoint of the initial roadbed filler and the bottom of the initial roadbed filler; After the pressurization is completed, the height change of the initial roadbed filling material is detected and recorded.

3. The indoor testing method for roadbed filler performance according to claim 2 is characterized in that: Determining whether the roadbed filler to be tested meets the filler deformation standard according to the pressurized stability test result includes: If the surface height change is less than the standard surface height change, and the pressure of each layer is within the corresponding change threshold range, it is determined that the roadbed filler to be tested meets the filler deformation standard.

4. The indoor testing method for roadbed filler performance according to claim 3 is characterized in that: The height of the same volume of water added to a sample of the initial state roadbed filling material and the stabilized roadbed filling material is lower than the height of the initial state roadbed filling material, and the water immersion height is higher than the midpoint of the initial state roadbed filling material.

5. The indoor testing method for roadbed filler performance according to claim 4 is characterized in that: Judging whether the roadbed filler to be tested meets the filler stability standard according to the detection result of the water immersion height includes: Calculate the height difference between the water immersion height of the initial state roadbed filling material and the water immersion height of the stable roadbed filling material sample; If the height difference is greater than the water immersion height difference threshold, it is determined that the roadbed filler to be tested does not meet the filler stability standard.

6. The indoor testing method for roadbed filler performance according to claim 5 is characterized in that: Using the second deformation pressure group to perform the pressurized deformation detection on each of the simulated roadbed fillers includes: The simulated roadbed filler is pressurized using level I load pressure, level II load pressure, and level III load pressure respectively; When the height of each simulated roadbed filler no longer changes, the height change of each simulated roadbed filler is determined respectively and recorded as the pressure deformation detection result; Wherein, the second deformation pressure group includes the level I load pressure, the level II load pressure and the level III load pressure.

7. The indoor testing method for roadbed filler performance according to claim 6 is characterized in that: The initial roadbed filler performance grade is determined in combination with the pressurized deformation results of each simulated roadbed filler, including: If the pressurized deformation result meets the first load condition, the initial roadbed filler grade is determined to be a first-class roadbed filler; If the pressurized deformation result meets the second load condition, the initial roadbed filler grade is determined to be a secondary roadbed filler; If the pressurized deformation result meets the third load condition, it is determined that the initial roadbed filler grade is a third-grade roadbed filler.

8. The indoor testing method for roadbed filler performance according to claim 7, characterized in that: The first load condition is that the deformation corresponding to the level I load pressure is smaller than the level I deformation; The second load condition is that the deformation amount corresponding to the level I load pressure is greater than or equal to the level I deformation amount, and the deformation amount corresponding to the level II load pressure is less than the level II deformation amount; The third load condition is that the deformation corresponding to the level I load pressure is greater than or equal to the level I deformation, the deformation corresponding to the level II load pressure is greater than or equal to the level II deformation, and the deformation corresponding to the level III load pressure is less than the level III deformation.

9. The indoor testing method for roadbed filler performance according to claim 8, characterized in that: Repeatedly using the pressure in the corresponding second deformation pressure group to perform simulated deformation detection on the simulated roadbed filler, comprising: Obtaining the performance grade of the initial roadbed filler, and determining the corresponding second deformation pressure and the preset number of simulations; The simulated roadbed filler is repeatedly pressurized using the corresponding second deformation pressure according to a preset number of simulations, and the final deformation amount is recorded.

10. The indoor testing method for roadbed filler performance according to claim 9, characterized in that: Determining whether to adjust the initial roadbed filler performance level according to the simulation results includes: If the final deformation amount meets the corresponding load condition, it is determined that the initial roadbed filler performance level is not adjusted, and is recorded as the performance level of the roadbed filler to be tested; If the final deformation amount does not meet the corresponding load condition, it is determined to adjust the performance level of the initial roadbed filling material.

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