A high-iron-filler vibration compaction mechanics state evaluation method and system

Abstract

The present disclosure relates to a high-filling-vibration-compaction-mechanical-state evaluation method and system, which comprises the following steps: S01, performing a vibration compaction test on the filling to be tested to obtain the vibration compaction stiffness of the filling to be tested based on a lagging phase angle correction; S02, performing an indoor load test on the filling to be tested to obtain the strength K 20 of the filling to be tested; S03, evaluating the vibration compaction mechanical state of the filling to be tested based on the vibration compaction stiffness and the strength K 20 . The system is used to implement the above method. The present disclosure introduces vibration compaction stiffness and strength as mechanical state evaluation indexes, which can better match the field vibration compaction standard, can more comprehensively reflect and evaluate the mechanical performance of the filling in the compaction state, realizes efficient, comprehensive and accurate analysis of the stiffness and strength of the filling indoor vibration test, and effectively improves the level of compaction effect evaluation test.

Description

TECHNICAL FIELD

[0001] The present disclosure relates to the technical field of subgrade filler mechanical property analysis, in particular to a high-speed railway filler vibration compaction mechanical state evaluation method and system. BACKGROUND

[0002] The high-speed railway subgrade bears the track and train load for a long time, and is extremely important infrastructure. The static and dynamic deformation control standard of the subgrade reaches the millimeter level, so the filling quality and efficiency of the subgrade are strictly required.

[0003] The high-speed railway subgrade is formed by compaction of granular fillers (hereinafter referred to as fillers), and its service performance is closely related to the compaction quality. The indoor vibration compaction test is performed on the fillers to evaluate the mechanical properties of the fillers in different compaction states, which will help guide the actual high-speed railway filling construction. At present, the physical index for detecting the compaction quality of the high-speed railway subgrade is mainly the compaction degree K. The compaction degree K is calculated by comprehensively measuring the in-situ dry density and the maximum dry density obtained by the indoor compaction test.

[0004] In engineering practice, the in-situ compaction standard of the railway not only includes the above-mentioned compaction degree K, but also includes the mechanical indexes of the ground coefficient K 30 , the dynamic deformation modulus E vd . Generally speaking, as the compaction density increases, the strength and stiffness of the subgrade will also be correspondingly improved. However, the coarse-grained soil is a relatively complex mixed material, and its properties are closely related to the particle size, shape, water content and grading parameters. The large variability of the coarse-grained soil caused by many related factors makes it necessary to analyze whether the increase of the compaction density will inevitably increase the stiffness and strength and other mechanical indexes according to the actual situation.

[0005] In the existing indoor compaction test of the railway, only the compaction physical state change index of the dry density p d is considered, and there is a lack of multi-level mechanical evaluation indexes, especially a lack of a scheme for evaluating the mechanical properties of the fillers from the aspects of strength deformation, filler stiffness and the like. Therefore, the matching between the indoor compaction standard and the in-situ vibration compaction standard is very low, it is difficult to comprehensively evaluate the mechanical properties of the fillers in the compaction state, and the popularization and application of the indoor vibration compaction test are limited. SUMMARY

[0006] In order to solve the problems existing in the prior art, the present disclosure aims to provide a high-speed railway filler vibration compaction mechanical state evaluation method and system. The present disclosure introduces the vibration compaction stiffness and strength as the mechanical state evaluation indexes, which can better match the in-situ vibration compaction standard, can more comprehensively reflect and evaluate the mechanical properties of the fillers in the compaction state, can realize efficient, comprehensive and accurate analysis of the stiffness and strength of the indoor vibration test of the fillers, and effectively improves the level of the compaction effect evaluation test.

[0007] The application discloses a high-iron-filler vibration compaction mechanical state evaluation method.

[0008] S01, performing a vibration compaction test on the to-be-tested filler to obtain vibration compaction stiffness of the to-be-tested filler based on a hysteresis phase angle correction;

[0009] S02, performing an indoor load test on the to-be-tested filler to obtain strength K 20 of the to-be-tested filler;

[0010] S03, evaluating a vibration compaction mechanical state of the to-be-tested filler based on the vibration compaction stiffness and the strength K 20 .

[0011] Preferably, the step S01 comprises:

[0012] S011, calculating the hysteresis phase angle according to a displacement change-time domain curve and an exciting force-time domain curve obtained in the vibration compaction test;

[0013] S012, calculating a stiffness index of the to-be-tested filler according to vibration compaction test parameters;

[0014] S013, correcting the stiffness index based on the hysteresis phase angle to obtain the vibration compaction stiffness.

[0015] Preferably, in the step S011, the hysteresis phase angle is calculated according to the following formula:

[0016]

[0017]

[0018] wherein represents the hysteresis phase angle, Δt represents a time difference between amplitudes of vibration displacement and exciting force of adjacent vibration devices in one sampling period, ω represents a rotating angular velocity of an eccentric block, k represents a period number of displacement in one sampling period, and Δt i represents an i-th time difference in one sampling period.

[0019] Preferably, in the step S012, the stiffness index K'2 of the to-be-tested filler is calculated according to the following formula:

[0020]

[0021] wherein ω represents a rotating angular velocity of an eccentric block, represents vibration acceleration of a vibration device, represents vibration velocity of the vibration device, and x represents vibration displacement of the vibration device. em represents eccentric mass, m d r represents vibration unit mass, r e e represents eccentricity.

[0022] Preferably, in the step S013, the vibration compaction stiffness K2 is calculated according to the following formula:

[0023]

[0024] Preferably, the step S02 comprises:

[0025] S021, based on the settlement index and the load intensity index, the field plate load test index K is calculated according to the following formula: 30 :

[0026] K 30 = σ s / S s ;

[0027] Wherein, S s represents the field settlement, σ s represents the field load intensity corresponding to the settlement reference value;

[0028] S022, analyze the alternative of the model after the scale to the original size test result, determine the similar ratio of each physical quantity of indoor and outdoor plate load test, based on the similarity theory, the similarity of indoor and outdoor plate load test is determined, and the sample strain similarity ratio C ε is obtained.

[0029] S023, according to the field plate load test index K 30 and the sample strain similarity ratio C ε , the strength K 20 is calculated.

[0030] Preferably, in the step S022, the similar ratio of each physical quantity of indoor and outdoor plate load test is specifically:

[0031] The geometric similarity ratio of the test piece is determined according to the following formula:

[0032]

[0033] The filler modulus similarity ratio is determined according to the following formula:

[0034]

[0035] The filler Poisson's ratio is determined according to the following formula:

[0036]

[0037] The stress similarity ratio is determined according to the following formula:

[0038]

[0039] The sample strain similarity ratio C is determined according to the following formula ε :

[0040]

[0041] The similarity determination of indoor and outdoor plate load tests based on the similarity theory is specifically:

[0042] μ0=μ1;

[0043]

[0044]

[0045]

[0046] Preferably, in the step S023, the strength K is calculated according to the following formula 20 :

[0047] K 20 =σ0 / S0;

[0048] S0=S s *C ε ;

[0049] Wherein, S0 represents the indoor test settlement, and σ0 represents the indoor load strength corresponding to the settlement reference value.

[0050] The high-filling vibration compaction mechanical state evaluation system comprises:

[0051] The vibration compaction stiffness analysis module is used for vibration compaction test on the to-be-tested filling, and obtains the vibration compaction stiffness of the to-be-tested filling based on the hysteresis phase angle correction.

[0052] The strength deformation analysis module is used for load test on the to-be-tested filling, and obtains the strength K of the to-be-tested filling 20 .

[0053] The mechanical state evaluation module is used for evaluating the vibration compaction mechanical state of the to-be-tested filling based on the vibration compaction stiffness and the strength K 20 .

[0054] Preferably, the vibration compaction stiffness analysis module comprises:

[0055] The vibration compaction equipment is used for vibration compaction test;

[0056] a data acquisition unit for acquiring vibration acceleration and eccentric block rotation angular velocity of the vibration compaction device;

[0057] a data transmission unit, which is in signal connection with the data acquisition unit, for transmitting data;

[0058] a preprocessing and display unit, which is in signal connection with the data transmission unit, for preprocessing and displaying the acquired data.

[0059] Preferably, the strength deformation analysis module comprises:

[0060] a sample container for carrying the to-be-tested filler;

[0061] a force application unit arranged above the sample container for applying force to extrude the to-be-tested filler;

[0062] a force measurement unit connected with the force application unit for measuring the pressure applied by the force application unit;

[0063] a displacement detection unit connected with the force application unit for measuring the depth of depression of the force application unit.

[0064] The high-speed railway filler vibration compaction mechanical state evaluation method and system have the advantages that the vibration compaction stiffness and the strength of the filler are introduced as evaluation indexes of the indoor compaction test, the problem that the existing compaction state evaluation mainly uses the dry density as a single evaluation physical index and lacks multi-level mechanical evaluation indexes is solved, the mechanical foundation coefficient K 30 and the dynamic deformation modulus E vd are respectively corresponded to the vibration compaction stiffness and the strength of the filler, the indoor compaction test can better match the field vibration compaction standard, the mechanical performance of the filler in the compaction state can be more comprehensively reflected and evaluated, efficient, comprehensive and accurate analysis of the stiffness and strength of the filler in the indoor vibration test is realized, the level of the compaction effect evaluation test is effectively improved, the indoor vibration compaction test is promoted and applied, and the filling quality of the high-speed railway foundation is improved. BRIEF DESCRIPTION OF DRAWINGS

[0065] Figure 1 is a step flowchart of the high-speed railway filler vibration compaction mechanical state evaluation method described in the embodiment;

[0066] Figure 2 is a flowchart of step 1 of the high-speed railway filler vibration compaction mechanical state evaluation method described in the embodiment;

[0067] Figure 3 is a flowchart of step 2 of the high-speed railway filler vibration compaction mechanical state evaluation method described in the embodiment;

[0068] Figure 4 is a structural block diagram of a high-speed rail filler vibration compaction mechanical state evaluation system described in the embodiment;

[0069] Figure 5 is a structural block diagram of a vibration compaction stiffness analysis module described in the embodiment;

[0070] Figure 6 is a structural diagram of a strength deformation analysis module described in the embodiment;

[0071] Figure 7 is a schematic diagram of displacement-time curve and excitation force-time curve obtained in the vibration compaction test of the embodiment;

[0072] Figure 8 is a schematic diagram of a 2-DOF dynamic model constructed in the vibration compaction test of the embodiment;

[0073] Figure 9 is a gradation curve diagram of the test filler in the vibration compaction test of the embodiment;

[0074] Figure 10 is a diagram of the change of the hysteresis phase angle with the vibration time in the vibration compaction test of the embodiment;

[0075] Figure 11 is a diagram of the calculation results of the vibration compaction stiffness of the filler in the vibration compaction test of the embodiment;

[0076] Figure 12 is a diagram of the calculation results of the strength K 20 in the vibration compaction process of the embodiment.

[0077] BRIEF DESCRIPTION OF DRAWINGS: 10-vibration compaction stiffness analysis module, 101-vibration compaction equipment, 102-data acquisition unit, 103-data transmission unit, 104-preprocessing and display unit, 20-strength deformation analysis module, 201-sample container, 202-force application unit, 203-force measurement unit, 204-displacement detection unit, 30-mechanical state evaluation module. DETAILED DESCRIPTION

[0078] As shown in Figures 1-12 , the high-speed rail filler vibration compaction mechanical state evaluation method described in the disclosure includes the following steps:

[0079] S01, vibration compaction test is performed on the test filler to obtain the vibration compaction stiffness of the test filler based on the hysteresis phase angle correction;

[0080] Step S01 specifically includes:

[0081] S011、According to the displacement change-time domain curve and the exciting force-time domain curve obtained by the vibration compaction test, the hysteresis phase angle is calculated; specifically as follows:

[0082] Considering the influence of the hysteresis phase angle on the calculation of the vibration compaction stiffness, and considering that the hysteresis phase angle will change with the compaction degree of the filler and the vibration frequency, after obtaining the displacement change-time domain curve and the exciting force-time domain curve of the vibration compaction test as shown in Figure 7 , the time interval Δt of the peak value in each period is compared, and the hysteresis phase angle is calculated according to the following formula

[0083]

[0084]

[0085] wherein, the hysteresis phase angle is represented, Δt represents the time difference between the amplitude of the vibration displacement and the exciting force of the adjacent vibration device in a sampling period, ω represents the rotational angular velocity of the eccentric block, k represents the number of cycles of the displacement in a sampling period, and Δt i represents the i-th time difference in a sampling period.

[0086] S012、According to the vibration compaction test parameters, the stiffness index of the filler to be tested is calculated; specifically as follows:

[0087] Combined with the theoretical method, a 2-DOF dynamic model as shown in Figure 8 is established, and the stiffness index of the filler is calculated through the model. The model is arranged from top to bottom as a weight block, a vibration unit and a filler. The weight block and the vibration unit are in contact with each other through a spring and a damping, and the filler is analogous to a spring and a damping.

[0088] Assuming that the force acting on the filler is located in the elastic-plasticity of the filler, the force balance analysis of the vibration compaction device 101 is carried out, and the following formula is obtained:

[0089]

[0090] The exciting force of the vibration device is calculated according to the following formula:

[0091] F=m e r e ω 2 sin(ωt);

[0092] According to the above two formulas, the calculation formula of the stiffness index K'2 is obtained:

[0093]

[0094] wherein, ω represents the rotational angular velocity of the eccentric block, represents the vibration acceleration of the vibrating device, represents the vibration speed of the vibrating device, x represents the vibration displacement of the vibrating device, m e represents the eccentric block mass, m d represents the vibration unit mass, r e represents the eccentric distance.

[0095] The above parameters are common parameters of the vibration compaction test, and can be obtained by reading the parameters of the vibration compaction instrument or setting corresponding conventional sensing elements for detection.

[0096] S013, based on the hysteresis phase angle, the stiffness index is corrected, and the vibration compaction stiffness is calculated and obtained, specifically as follows:

[0097] In the 2-DOF dynamic model as shown in Figure 8 , the interaction force between the upper module and the lower module is not considered, only the upper static load counterweight is considered, the stiffness index K'2 calculation formula is simplified, and the following formula is obtained:

[0098]

[0099] Based on the simple harmonic vibration theory, when the speed of the vibrating device is 0, i.e. , at this time, the vibration device acceleration and displacement take the maximum value, it is assumed that the excitation force reaches the maximum value at t=t0, the vibrating device displacement reaches the maximum value at t=t1, and the difference between t0 and t1 is equal to the hysteresis phase angle The stiffness of the filler at each time in a vibration cycle is constant, and the stiffness K2 at t=t1 can be used to represent the stiffness value K2 in the whole cycle; based on the above, the vibration compaction stiffness calculation formula after correcting the hysteresis phase angle is established:

[0100]

[0101] S02, indoor load test is carried out on the to-be-tested filler, and the strength K 20 of the to-be-tested filler is obtained.

[0102] Step S02 specifically includes:

[0103] S021, based on the settlement amount index and the load strength index, the field plate load test index K 30 is calculated according to the following formula:

[0104] K 30 = σ s / S s ;

[0105] Wherein, S s represents the field settlement amount, and σ srepresents the load intensity corresponding to the subsidence amount reference value; in a conventional load test, S s is a fixed value of 1.25 mm.

[0106] S022、analyze the alternative of the model after the scale relative to the original size test results, determine the similarity ratio of each physical quantity of the indoor and outdoor flat plate load test; based on the similarity theory, the similarity of the indoor and outdoor flat plate load test is determined, and the sample strain similarity ratio C ε ;

[0107] Specifically, the scale model mainly considers the size effect between the size of the load plate in the test site and the soil sample diameter of the indoor vibration compaction equipment 101. For example, when the soil sample diameter of the indoor vibration compaction equipment 101 is 300 mm, the size of the load plate in the field flat plate load test is 300 mm. In order to ensure that the indoor measurement compaction index corresponds to the K 30 result obtained by the field test, the size of the load plate in the indoor test is set to 200 mm.

[0108] The soil sample size adopted by the indoor vibration compaction instrument is 300 mm, which does not meet the size requirement of the K 30 test on the size of the load plate, K 30 can reflect the strength of the soil sample within 1.5-2 times the diameter of the load plate, so the diameter of the indoor load plate is selected to be 200 mm.

[0109] In order to ensure that the compaction index tested in the indoor test is the same as the foundation coefficient index tested in the field, the size of the load plate must meet the similarity theory to obtain effective analysis conclusion.

[0110] Among them, the similarity ratio of each physical quantity of the indoor and outdoor flat plate load test is specifically:

[0111] The geometric similarity ratio of the test piece is determined according to the following formula:

[0112]

[0113] The modulus similarity ratio of the filler is determined according to the following formula:

[0114]

[0115] The Poisson's ratio of the filler is determined according to the following formula:

[0116]

[0117] The stress similarity ratio is determined according to the following formula:

[0118]

[0119] The sample strain similarity ratio C ε:

[0120]

[0121] The relationship between the physical quantities is converted into a dimensionless equation by combining the similarity theory, and the indoor load test similarity determination is specifically:

[0122] μ0=μ1;

[0123]

[0124]

[0125]

[0126] S023、According to the field plate load test index K 30 and the sample strain similarity ratio C ε , the strength K 20 is calculated, specifically, the strength K 20 is calculated according to the following formula:

[0127] K 20 =σ0 / S0;

[0128] S0=S s *C ε ;

[0129] Wherein, S0 represents the indoor test subsidence, σ0 represents the subsidence reference value corresponding to the indoor load strength, for example, since the filler is consistent in the indoor test and the outdoor field test, that is, the Poisson's ratio and the elastic modulus of the filler are basically consistent, that is, the above-mentioned filler modulus similarity ratio and the filler Poisson's ratio are equal to 1, taking the load plate size in the above-mentioned field plate load test as 300mm and the load plate size in the indoor test as 200mm as an example, the above-mentioned geometric similarity ratio is 2 / 3, and the sample strain similarity ratio is 2 / 3 according to the geometric similarity ratio and the above-mentioned formula.

[0130] In order to ensure that the stress value of the sample surface in the indoor and outdoor tests is equal, it can be obtained from the formula that the vertical loading in the indoor and outdoor tests should be 4:9, that is:

[0131] For example, taking the above-mentioned S s as a fixed value of 1.25mm, then

[0132] The strength K 20 is calculated according to the above-mentioned calculation formula of the strength K 20 .

[0133] S03、Based on the vibration compaction stiffness and the strength K 20, and specifically, according to the requirements of the filling quality and filling efficiency of the high-speed railway foundation and the mechanical index foundation coefficient K 30 , dynamic deformation modulus E vd of the railway site compaction standard, the comprehensive vibration compaction mechanical state of the filling is analyzed and evaluated.

[0134] The present disclosure solves the problem that the existing compaction state evaluation mainly takes dry density as a single evaluation physical index and lacks multi-level mechanical evaluation indexes by introducing vibration compaction stiffness and strength of the filling as evaluation indexes of the indoor compaction test. The vibration compaction stiffness and the strength of the filling correspond to the mechanical foundation coefficient K 30 and the dynamic deformation modulus E vd , respectively, so that the indoor compaction test can better match the site vibration compaction standard, can more comprehensively reflect and evaluate the mechanical performance of the filling under the compaction state, can realize efficient, comprehensive and accurate analysis of the stiffness and strength of the indoor vibration test of the filling, effectively improves the level of the compaction effect evaluation test, is conducive to the popularization and application of the indoor vibration compaction test, and is also helpful to improve the filling quality of the high-speed railway foundation.

[0135] As shown in Figure 4 , the embodiment further provides a high-speed railway filling vibration compaction mechanical state evaluation system, comprising:

[0136] a vibration compaction stiffness analysis module 10, which is used for performing a vibration compaction test on a to-be-tested filling to obtain vibration compaction stiffness of the to-be-tested filling based on a hysteresis phase angle correction;

[0137] a strength deformation analysis module 20, which is used for performing a load test on the to-be-tested filling to obtain strength K 20 of the to-be-tested filling;

[0138] a mechanical state evaluation module 30, which is used for evaluating a vibration compaction mechanical state of the to-be-tested filling based on the vibration compaction stiffness and the strength K 20 .

[0139] Specifically, as shown in Figure 5 , the vibration compaction stiffness analysis module 10 comprises:

[0140] a vibration compaction device 101, which is usually a vibration compaction instrument and is used for performing a vibration compaction test on the filling;

[0141] The data acquisition unit 102 is used to acquire the vibration acceleration and angular velocity of the eccentric block of the vibratory compaction equipment 101. Specifically, the data acquisition unit 102 includes a triaxial accelerometer and a Hall sensor. The data acquisition unit 102 is connected to dynamic testing equipment, such as the Donghua Dynamic Testing Equipment. The triaxial accelerometer is fixed to one side of the vibratory equipment and can measure the vibration acceleration in the X, Y, and Z directions respectively. The Hall sensor is fixed to one side of the eccentric block of the vibratory compaction equipment 101 and does not rotate with the eccentric block. The sensing magnet is connected to the eccentric block and is used to acquire the angular velocity of the eccentric block when it rotates, in order to calculate the hysteresis phase angle.

[0142] The data transmission unit 103 is signal-connected to the data acquisition unit 102 and is used to transmit data;

[0143] The preprocessing and display unit 104, which is signal-connected to the data transmission unit 103, is used to preprocess and display the collected data. The preprocessing and display unit 104 can be the analysis software and display interface built into the dynamic testing equipment mounted on a computer. By performing two frequency integration operations on the collected acceleration data, the following can be obtained: Figure 7 The displacement-time domain curves and excitation force-time domain curves are shown and displayed.

[0144] like Figure 6 As shown, the strength deformation analysis module 20 includes:

[0145] Sample container 201 is used to hold the test packing material;

[0146] The force application unit 202 is disposed above the sample container 201 and is used to apply force to compress the filler to be tested; the force application unit 202 can be a hydraulic pressurizing device such as a jack.

[0147] The force measuring unit 203 is connected to the force applying unit 202 and is used to measure the pressure applied by the force applying unit 202; it can be a force measuring ring or a force sensor, etc.

[0148] The displacement detection unit 204, connected to the force application unit 202, is used to measure the pressing depth of the force application unit 202. A dial indicator or displacement sensor can be used.

[0149] The aforementioned strength deformation analysis module 20 is used for conducting routine indoor load tests.

[0150] The vibration compressive strength mechanical state assessment system for high-speed railway packing in this embodiment is based on the same inventive concept as the method embodiment described above. It can be understood with reference to the description of the method embodiment above, and will not be repeated here.

[0151] The implementation process of the method for evaluating the mechanical state of high-speed railway filler vibration compaction will be described in detail below in combination with the above.

[0152] The test filler was obtained and the vibration parameters of the test were set.

[0153] The test filler was taken from the filler of the Beijing-Xiong'an high-speed railway. The gradation and the optimal water content curve of the filler were determined through sieve test and compaction test, as shown in Figure 9 The maximum particle size of the filler gradation is 40 mm, the curvature coefficient Cc is 1.0, the non-uniformity coefficient Cu is 80, and the optimal water content is 6%.

[0154] The vibration frequency was set to 20-35 Hz, the vibration amplitude was set to 0.6 mm, and the container diameter was set to D = 300 mm.

[0155] After connecting all the units in the indoor vibration compaction filler stiffness analysis module for high-speed railway filler, the power was turned on, and the system was started. The time-domain curve of displacement change and the time-domain curve of excitation force were obtained at the data display and preprocessing end of the system. The peak time interval in each cycle was compared, and the hysteresis phase angle of the filler under different vibration times was calculated, as shown in Figure 10

[0156] As can be seen from Figure 10 , with the increase of the compaction degree of the filler, the hysteresis phase angle gradually decreases, and when the filler is compacted, the hysteresis phase angle gradually stabilizes. During the compaction process of the filler, the natural frequency of the system increases, while the external input frequency remains unchanged, resulting in a gradual decrease in the frequency ratio and a gradual decrease in the dimensionless damping, thereby reducing the hysteresis phase angle. With the increase of the compaction degree, the natural frequency of the system remains unchanged, the stiffness and damping of the filler remain basically unchanged, and the hysteresis phase angle also stabilizes.

[0157] The indoor vibration compaction filler stiffness analysis was carried out by the vibration compaction stiffness analysis method based on the correction of the hysteresis phase angle, and the results are shown in Figure 11

[0158] As can be seen from Figure 11 , when the vibration frequency is less than 25 Hz, the stiffness of the filler increases with the increase of the vibration frequency; when the vibration frequency is greater than 25 Hz, the stiffness of the filler decreases with the increase of the vibration frequency. It is worth noting that when the vibration frequency is in the resonance interval of 25-30 Hz, the stiffness of the filler gradually decreases, which can be explained by the vibration friction reduction machine. When the vibration frequency is less than 25 Hz, the vibration intensity is small, and the inertia force of the particles in the vibration field is not enough to make the particles escape from the constraint, so the vibration friction reduction effect is not obvious. When the vibration frequency is greater than 25 Hz, the vibration intensity is large, and the vibration friction reduction effect occurs in the soil, resulting in a decrease in the stiffness of the filler.

[0159] ​​In conclusion, the indoor vibration compaction stiffness analysis of high-speed railway filling material is carried out by using the indoor vibration compaction stiffness analysis module 10 of high-speed railway filling material, and the obtained result conforms to scientific laws, and the efficient analysis of the indoor vibration compaction stiffness index of high-speed railway filling material can be realized, and the compaction state of high-speed railway filling material can be better reflected.

[0160] After connecting each unit in the strength deformation analysis module 20 of indoor vibration compaction filling material of high-speed railway filling material, the filling material sample is placed in the container, the system is started, and the indoor flat plate load test is carried out. In the test, in order to ensure that the load plate is in full contact with the surface of the filling material to be compressed, a small load should be applied to the load plate before loading, and then the load is removed;

[0161] In the test process, the hierarchical loading method is adopted, and 1 / 8 of the maximum stress corresponding to the load result is taken as the load increment. After each level of loading, if the sink amount of the dial gauge in one minute is less than 1% of the total settlement amount of this level, the loading is stopped, and the test is ended.

[0162] In the vibration compaction process, the data is read every 25s, and the sink amount S s and the load strength σ0 at each time in the test process are obtained.

[0163] The filling material strength analysis method based on the similarity theory is adopted for analysis and calculation, and the flat plate load index K 20 of the sample at each time in the test process is obtained, and the result is shown in Figure 12 .

[0164] As shown in Figure 12 , K 20 gradually increases in the vibration compaction process, and the amplitude gradually decreases, which is consistent with the previous research. When the vibration frequency is in the resonance interval, K 20 significantly increases, which indicates that the bearing capacity of the subgrade structure can be improved by using the resonance frequency for compaction. In conclusion, the strength analysis and evaluation are carried out by using the indoor vibration compaction filling material strength analysis system of high-speed railway filling material, the obtained result conforms to scientific laws, the efficient analysis of the indoor vibration compaction strength index of high-speed railway filling material can be realized, and the compaction state of high-speed railway filling material can be better reflected.

[0165] In the description of the present disclosure, it should be understood that the orientation words such as "front, back, up, down, left, right", "transverse, vertical, horizontal" and "top, bottom" and the like indicate the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present disclosure and simplifying the description, without the opposite description, these orientation words do not indicate and imply that the indicated device or element must have a specific orientation or be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the protection scope of the present disclosure.

[0166] For those skilled in the art, other various corresponding changes and modifications can be made according to the technical solutions and concepts described above, and all these changes and modifications should belong to the protection scope of the claims of the present disclosure.

Claims

1. A method for evaluating the vibration compressive strength mechanical state of high-speed railway packing, characterized in that, Includes the following steps: S01. Perform a vibration compaction test on the filler to be tested to obtain the vibration compaction stiffness of the filler to be tested based on the hysteresis phase angle correction; Step S01 includes: S011. Calculate the hysteresis phase angle based on the displacement change-time domain curve and excitation force-time domain curve obtained from the vibration compaction test; S012. Calculate the stiffness index of the filler to be tested based on the vibration compaction test parameters. S013. Based on the hysteresis phase angle, the stiffness index is corrected, and the vibration compaction stiffness is calculated. In step S011, the hysteresis phase angle is calculated according to the following formula. in, The lag phase angle is represented by Δt, which represents the time difference between the vibration displacement and the amplitude of the excitation force of adjacent vibrating devices within one sampling period. ω represents the rotational angular velocity of the eccentric block, and k represents the number of displacement cycles within one sampling period. i This represents the i-th time difference within a sampling period; In step S012, the stiffness index K′2 of the filler to be tested is calculated according to the following formula: Where ω represents the angular velocity of the eccentric block. This indicates the vibration acceleration of the vibrating equipment. Let x represent the vibration velocity of the vibrating equipment, and let x represent the vibration displacement of the vibrating equipment, in meters. e The mass of the eccentric block is m. d The mass r of the vibrating element represents the mass of the vibrating element. e Indicates the eccentricity; In step S013, the vibration compaction stiffness K2 is calculated according to the following formula: S02. Perform an indoor load test on the packing material to be tested to obtain the strength K of the packing material. 20 ; Step S02 includes: S021. Calculate the field plate load test index K based on the settlement index and load strength index using the following formula. 30 : K 30 =s s / S s ; Among them, S s σ represents the on-site subsidence. s This indicates the on-site load intensity corresponding to the benchmark value of settlement; S022. Analyze the substitutability of the scaled-down model with the original size test results, determine the similarity ratio of each physical quantity in the indoor and outdoor plate load tests, and make similarity judgments for the indoor and outdoor plate load tests based on similarity theory to obtain the strain similarity ratio C of the indoor and outdoor plate load tests. ε ; S023, According to the on-site plate load test index K 30 The strain similarity ratio C of the specimen ε Calculate the intensity K 20 ; S03, Based on the vibration compaction stiffness and the strength K 20 The vibration compressive strength of the packing material to be tested is evaluated.

2. The method for evaluating the vibration compressive strength of high-speed railway packing according to claim 1, characterized in that, In step S022, the similarity ratio of each physical quantity in the indoor and outdoor plate load tests is determined as follows: The geometric similarity ratio of the specimens is determined using the following formula: Determine the similarity ratio of filler modulus using the following formula: Determine the Poisson's ratio of the packing material using the following formula: The stress similarity ratio is determined using the following formula: The strain similarity ratio C of the specimen is determined according to the following formula. ε : The similarity determination for indoor and outdoor plate load tests based on similarity theory is as follows: μ0 = μ1; 3. The method for evaluating the vibration compressive strength of high-speed railway packing according to claim 2, characterized in that, In step S023, the strength K is calculated according to the following formula. 20 : K 20 =σ0 / S0; S0=S s *C ε ; Where S0 represents the indoor test settlement, and σ0 represents the indoor load strength corresponding to the settlement benchmark value.

4. A vibration compressive strength mechanical state assessment system for high-speed railway packing, characterized in that, include: The vibration compaction stiffness analysis module is used to perform vibration compaction tests on the test filler material and obtain the vibration compaction stiffness of the test filler material based on hysteresis phase angle correction; specifically: The hysteresis phase angle is calculated based on the displacement change-time domain curve and excitation force-time domain curve obtained from the vibration compaction test. Based on the vibration compaction test parameters, the stiffness index of the filler to be tested is calculated; Based on the hysteresis phase angle, the stiffness index is corrected, and the vibration compaction stiffness is calculated. The hysteresis phase angle is calculated using the following formula. in, The lag phase angle is represented by Δt, which represents the time difference between the vibration displacement and the amplitude of the excitation force of adjacent vibrating devices within one sampling period. ω represents the rotational angular velocity of the eccentric block, and k represents the number of displacement cycles within one sampling period. i This represents the i-th time difference within a sampling period; The stiffness index K′2 of the packing material to be tested is calculated using the following formula: Where ω represents the angular velocity of the eccentric block. This indicates the vibration acceleration of the vibrating equipment. Let x represent the vibration velocity of the vibrating equipment, and let x represent the vibration displacement of the vibrating equipment, in meters. e The mass of the eccentric block is m. d The mass r of the vibrating element represents the mass of the vibrating element. e Indicates the eccentricity; The vibration compaction stiffness K2 is calculated using the following formula: The strength-deformation analysis module is used to perform load tests on the packing material under test and obtain the strength K of the packing material under test. 20 ; Among them, the field plate load test index K is calculated based on the settlement index and the load strength index according to the following formula. 30 : K 30 =s s / S s ; Among them, S s σ represents the on-site subsidence. s This indicates the on-site load intensity corresponding to the benchmark value of settlement; The substitutability of the scaled-down model with the original size test results was analyzed to determine the similarity ratio of each physical quantity in the indoor and outdoor plate load tests. Based on similarity theory, the similarity judgment of the indoor and outdoor plate load tests was performed to obtain the strain similarity ratio C of the specimens in the indoor and outdoor plate load tests. ε ; According to the on-site plate load test index K 30 The strain similarity ratio C of the specimen ε Calculate the intensity K 20 ; The mechanical state assessment module is used to assess the vibration compaction stiffness and the strength K. 20 The vibration compressive strength of the packing material to be tested is evaluated.

5. The high-speed rail packing vibration compressive strength mechanical state assessment system according to claim 4, characterized in that, The vibration compaction stiffness analysis module includes: Vibratory compaction equipment, used for conducting vibration compaction tests; The data acquisition unit is used to collect the vibration acceleration and angular velocity of the eccentric block of the vibratory compaction equipment. A data transmission unit, which is signal-connected to the data acquisition unit, is used to transmit data; A preprocessing and display unit, which is signal-connected to the data transmission unit, is used to preprocess and display the collected data.

6. The high-speed rail packing vibration compressive strength mechanical state assessment system according to claim 4, characterized in that, The strength deformation analysis module includes: Sample container, which is used to hold the test packing material; A force-applying unit, which is positioned above the sample container, is used to apply force to compress the test filler. A force measuring unit, which is connected to the force applying unit, is used to measure the pressure applied by the force applying unit; A displacement detection unit, which is connected to the force application unit, is used to measure the downward pressure depth of the force application unit.

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