Method for determining shear strength parameter of cemented coarse-grained soil with super-large particle size

Abstract

The invention provides a method for determining shear strength parameters of cemented coarse-grained soil with oversized particle size, which belongs to the technical field of engineering investigation and measurement, and comprises the following steps: taking an undisturbed sample; carrying out an indoor flat pushing method direct shear test on the undisturbed sample to obtain a plurality of cohesive force data; performing data processing on the multiple pieces of cohesion data to obtain an undisturbed sample cohesion standard value; a disturbance sample is adopted; performing an indoor vertical pressurization direct shear test on the disturbance sample to obtain a plurality of internal friction angle data; performing data processing on the plurality of internal friction angle data to obtain a disturbance sample internal friction angle standard value; and determining the cohesive force standard value of the undisturbed sample and the internal friction angle standard value of the disturbance sample as shear strength parameters of the cemented coarse-grained soil with the ultra-large particle size, wherein the maximum particle size of soil particles of the cemented coarse-grained soil with the ultra-large particle size exceeds 200mm. According to the method, the obtained result is accurate, the test cost can be saved by 90% or above, the test period is greatly shortened, and meanwhile potential safety hazards of on-site in-situ tests can be avoided.

Description

Technical Field

[0001] The present invention belongs to the technical field of engineering investigation and measurement, and more specifically, relates to a method for determining shear strength parameters of cemented coarse-grained soil with super-large particle size. Background Art

[0002] my country's southwest region is rich in hydropower resources, and many large-scale hydropower projects are under construction or planned. The region's terrain is highly undulating, and in areas with well-developed rivers, large-grained coarse-grained soils, formed by various factors such as alluvial deposits, floodplains, glacial deposits, and collapse deposits, are widely distributed. These large-grained coarse-grained soils often exhibit varying degrees of cementation. Hydropower and water conservancy projects often involve these cemented large-grained coarse-grained soils, and the stability of foundations and slopes has a significant impact on project safety and long-term operation. Shear strength is a key parameter required for foundation and slope stability analysis. The appropriate method for determining the shear strength parameters of cemented large-grained coarse-grained soils has become a prominent issue that needs to be addressed in hydropower and water conservancy project construction.

[0003] In current engineering practice, obtaining soil shear strength parameters is typically performed using either indoor or in-situ tests. For cemented, oversized coarse-grained soils, due to their extremely large particles (maximum diameter exceeding 200 mm, with some exceeding 1 m), it is impossible to obtain undisturbed samples that meet testing requirements (sample size must be greater than five times the maximum soil particle size), and testing equipment suitable for such large-scale samples is unavailable. Therefore, in-house shear tests are performed using disturbed coarse-grained soil samples, reshaped to a scaled form according to the original gradation, and then reconstructed.

[0004] However, scaled and reshaped specimens have two major drawbacks for cemented, oversized coarse-grained soils: first, the gradation of the scaled specimens differs significantly from the actual specimens; second, the specimens no longer retain their original cementation after reshaping and disturbance, making the test results unrepresentative of the soil's engineering properties. Furthermore, in-situ testing involves excavating large-scale pits on-site for shear testing, but this is expensive, time-consuming, and labor-intensive, making it impractical for widespread adoption. Furthermore, the shear box size for field tests (currently the maximum size available is 55 cm × 55 cm × 35 cm) is extremely limited relative to the maximum particle size in the soil, making it unrealistic to increase the size of the shear box to improve the accuracy of the test results. Summary of the Invention

[0005] The present invention aims to provide a method for determining the shear strength parameters of cemented, extra-large coarse-grained soils, thereby overcoming the shortcomings of existing technologies in determining the shear strength parameters of cemented, extra-large coarse-grained soils. The method combines indoor push-to-roll direct shear tests with indoor vertical pressure direct shear tests by rationally arranging undisturbed and disturbed samples, and then comprehensively analyzes the test data to determine the shear strength parameters of the cemented, extra-large coarse-grained soils. The method offers the advantages of accurate results, cost savings, and a shortened testing period.

[0006] The term "cemented, ultra-large coarse-grained soil" herein refers to soil with a maximum particle size exceeding 200 mm and exhibiting cementitious properties. Cementation refers to the process by which separate soil particles are bonded and welded together by a binder. Cemented soil has a compact structure, while uncemented soil has a loose structure.

[0007] To achieve the above object, the present invention provides a method for determining the shear strength parameters of cemented oversized coarse-grained soil based on comprehensive indoor tests, comprising the following steps:

[0008] Take the original sample;

[0009] Conducting an indoor direct shear test using the horizontal push method on the original sample to obtain multiple cohesion data;

[0010] Processing the plurality of cohesion data to obtain a standard value of the original cohesion;

[0011] Take disturbance samples;

[0012] Performing an indoor vertical pressure direct shear test on the disturbance sample to obtain a plurality of internal friction angle data;

[0013] Processing the plurality of internal friction angle data to obtain a standard value of the disturbance sample internal friction angle;

[0014] The standard value of the cohesion of the original sample and the standard value of the internal friction angle of the disturbed sample are determined as the shear strength parameters of the cemented super-large coarse-grained soil, and the maximum particle size of the soil particles of the cemented super-large coarse-grained soil exceeds 200 mm.

[0015] Furthermore, the standard value of the original sample cohesion is calculated according to the following method:

[0016] Calculate the average value C of the multiple cohesion data pm and standard deviation σ, each of the cohesion data in [C pm -3σ, C pm +3σ] range;

[0017] Calculate the coefficient of variation of cohesion of the original sample

[0018] Calculate the statistical correction coefficient of cohesion of the original sample Ψ = 1-0.826δ;

[0019] Calculate the standard value of cohesion C of the original sample pk =ΨC pm .

[0020] Furthermore, the standard value of the internal friction angle of the disturbance sample is calculated according to the following method:

[0021] Calculate the average value of multiple internal friction angle data and standard deviation σ, each of the internal friction angle data in within the scope;

[0022] Calculation of the coefficient of variation of the internal friction angle of the disturbed sample

[0023] Calculate the statistical correction coefficient of the internal friction angle of the disturbed sample Ψ = 1-0.826δ;

[0024] Calculate the standard value of the internal friction angle of the disturbance sample

[0025] Furthermore, the original sample is gravel soil with a maximum soil particle size of ≤30 mm.

[0026] Furthermore, the original sample is in a cubic shape, the sample size is 20cm×20cm×20cm, and the number of samples taken is ≥6 pieces.

[0027] Furthermore, when sampling the disturbed sample, large stones with a particle size greater than 30 mm in each sample are screened out, and the mass of each sample after screening out the large stones is not less than 50 kg.

[0028] Furthermore, the disturbed sample is a sample prepared by a similar gradation method.

[0029] Furthermore, the disturbance samples include multiple groups, each group includes multiple samples, and the difference in vertical pressure applied between the multiple samples in each group is 200 kPa.

[0030] Furthermore, the disturbance samples include 6 groups, each group includes 4 samples, and the vertical pressures of the 4 samples in each group are 200 kPa, 400 kPa, 600 kPa, and 800 kPa, respectively.

[0031] Compared with the prior art, the present invention has the following technical effects:

[0032] The present invention provides a method for determining the shear strength parameters of cemented coarse-grained soil with extra-large particle size. The method combines indoor push-to-roll direct shear tests and indoor vertical pressure direct shear tests by rationally arranging undisturbed and disturbed samples. After comprehensive analysis and processing of the test data, the standard values ​​of the cohesion of the undisturbed samples and the standard values ​​of the internal friction angle of the disturbed samples are determined as the shear strength parameters of the cemented coarse-grained soil with extra-large particle size. Compared with the indoor shear tests for coarse-grained soil specified in current technical standards, the method of the present invention considers the influence of the soil's cementation state on the shear strength parameters, resulting in more accurate results. Furthermore, compared with the on-site in-situ shear tests specified in current technical standards, the method of the present invention achieves comparable results, saves over 90% of testing costs, significantly shortens the testing period, and avoids the safety hazards associated with deep pit excavation and heavy loads required for on-site in-situ testing. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0034] Figure 1 A flow chart of a method for determining shear strength parameters of cemented coarse-grained soil with ultra-large particle size provided in an embodiment of the present invention. DETAILED DESCRIPTION

[0035] In order to make the technical problems, technical solutions and beneficial effects to be solved by the present invention more clearly understood, the present invention is further described in detail below in conjunction with the embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0036] The terms used in the embodiments of the present invention are only for the purpose of describing specific embodiments and are not intended to limit the present invention. The singular forms "a", "an", "the" and "the" used in the embodiments of the present invention and the appended claims are also intended to include plural forms unless the context clearly indicates otherwise.

[0037] The embodiment of the present invention provides a method for determining the shear strength parameters of cemented super-large coarse-grained soil based on comprehensive indoor tests, the process of which is as follows: Figure 1 As shown, the following steps are included:

[0038] Step S1-1, taking an original sample;

[0039] Step S1-2, performing an indoor direct shear test on the original sample using the horizontal push method to obtain multiple cohesion data;

[0040] Step S1-3, analysis of direct shear test data using the horizontal push method: processing multiple cohesion data to obtain the standard value of the cohesion of the original sample;

[0041] Step S2-1, taking a disturbance sample;

[0042] Step S2-2, performing an indoor vertical pressure direct shear test on the disturbed sample to obtain multiple internal friction angle data;

[0043] Step S2-3, vertical pressure direct shear test data analysis: performing data processing on a plurality of internal friction angle data to obtain a standard value of the internal friction angle of the disturbance sample;

[0044] Step S3, determining the shear strength parameters of the cemented super-large coarse-grained soil: the standard value of the cohesion of the original sample and the standard value of the internal friction angle of the disturbed sample are determined as the shear strength parameters of the cemented super-large coarse-grained soil.

[0045] In step S1-1 above, the undisturbed sample is gravelly soil with a maximum particle size of 30 mm or less, within a cemented, oversized coarse-grained soil. Specifically, the undisturbed sample is a cube with dimensions of 20 cm × 20 cm × 20 cm. Six or more samples are collected, typically six to minimize the experimental workload. This ensures that the sample size is greater than or equal to six times the maximum particle size, eliminating the influence of size effects on the test results.

[0046] The original square samples should be wrapped with tape and placed in a soft, shock-proof sample box to avoid changes in their original bonding structure during transportation.

[0047] In the above step S1-2, the direct shear test adopts the horizontal push method, and the vertical pressure is set to 0. Through the horizontal push method direct shear test, 6 cohesion C values ​​of 6 original samples can be obtained. pi (i=1,2,…,6) data, respectively C p1 、C p2 、C p3 、C p4 、C p5 、C p6 .

[0048] The direct shear test using the horizontal push method was carried out in accordance with the provisions of "66 Direct Shear Test of Coarse-Grained Soil" in the "Standard for Geotechnical Test Methods (GB / T 50123-2019)" and "11 Direct Shear Test of Coarse-Grained Soil" in the "Test Procedure for Coarse-Grained Soil in Hydropower and Water Conservancy Projects (DL / T 5356-2006)".

[0049] In the above step S1-3, the average value C of the cohesion data of the plurality of original samples is calculated. pm ,

[0050] Calculate the standard deviation σ of multiple undisturbed sample cohesion data,

[0051] If the cohesion C pi <C pm -3σ or >C pm +3σ, the data is an abnormal value and should be eliminated. At the same time, the same number of original samples as the number of eliminated data should be taken and the direct shear test of the flat push method should be carried out to ensure the cohesion C p There are 6 test data, each cohesion C pi The data should be in [C pm -3σ, C pm+3σ] range.

[0052] Calculate the coefficient of variation of the cohesion of the original sample δ,

[0053] Calculate the statistical correction coefficient Ψ of the original sample cohesion, Ψ = 1-0.826δ.

[0054] Calculate the standard value of cohesion C of the original sample pk , C pk =ΨC pm .

[0055] In step S2-1 above, the sample was collected from cemented, oversized coarse-grained soil. Large rocks with a particle size greater than 30 mm were screened out from each sample on-site to facilitate transport. After removing the large rocks, each sample weighed no less than 50 kg to meet the requirements for subsequent sample preparation using the similar gradation method. Specifically, six groups of disturbed samples were collected, each containing four samples, for a total of 24 samples.

[0056] In the above step S2-2, each disturbed sample is prepared into a specimen using the similar gradation method in the laboratory. The vertical pressure direct shear test is carried out in groups. The vertical pressure of the four samples in each group can be 200kPa, 400kPa, 600kPa, and 800kPa respectively. Through the vertical pressure direct shear test, each group of disturbed samples can obtain a cohesion C di and an internal friction angle φ di Data, cohesion C di C d1 、C d2 、C d3 、C d4 、C d5 、C d6 , internal friction angle φ di They are

[0057] The vertical compression direct shear test is carried out in accordance with the relevant provisions of "66 Direct Shear Test of Coarse-Grained Soil" in the "Standard for Geotechnical Test Methods (GB / T 50123-2019)" and "11 Direct Shear Test of Coarse-Grained Soil" in the "Test Procedure for Coarse-Grained Soil in Hydropower and Water Conservancy Projects (DL / T 5356-2006)".

[0058] In the above step S2-3, only the internal friction angle data obtained from the disturbance sample vertical pressure direct shear test is analyzed.

[0059] Calculate the average internal friction angle of the disturbed sample

[0060] Calculate the standard deviation σ of the internal friction angle of the disturbance sample,

[0061] If the internal friction angle or At the same time, the same number of disturbance samples as the number of data to be eliminated should be taken and vertical pressure direct shear test should be carried out to ensure that the internal friction angle There are 6 test data, each internal friction angle The data should be within the range.

[0062] Calculate the coefficient of variation δ of the internal friction angle of the disturbance sample,

[0063] Calculate the statistical correction coefficient Ψ of the internal friction angle of the disturbed sample, Ψ = 1-0.826δ.

[0064] Calculate the standard value of the internal friction angle of the disturbed sample

[0065] In the above step S3, the original sample cohesion standard value C pk , Standard value of internal friction angle of disturbance sample As the cohesion C and internal friction angle of cemented super-large coarse-grained soil, That is, the cohesion of cemented super-large coarse-grained soil is C=C pk , internal friction angle

[0066] A method for determining the shear strength parameters of cemented coarse-grained soil with extra-large particle size, according to an embodiment of the present invention, rationally arranges the use of undisturbed and disturbed samples, combines indoor push-pull direct shear tests with indoor vertical pressure direct shear tests, and after comprehensive analysis and processing of the test data, determines the standard values ​​of the cohesion of the undisturbed samples and the standard values ​​of the internal friction angle of the disturbed samples as the shear strength parameters of the cemented coarse-grained soil with extra-large particle size. Compared with indoor shear tests of coarse-grained soil prescribed by current technical standards, the method of the embodiment of the present invention considers the influence of the soil's cementation state on the shear strength parameters, resulting in more accurate results. Furthermore, compared with on-site in-situ shear tests prescribed by current technical standards, the method of the embodiment of the present invention achieves results of comparable accuracy, saves over 90% of testing costs, significantly shortens testing time, and avoids the safety hazards associated with deep trench excavation and heavy loads required for on-site in-situ testing.

[0067] The following describes a method for determining the shear strength parameters of cemented, ultra-large coarse-grained soil based on comprehensive laboratory testing, using a specific example from a construction site in Tibet. The site contained a Quaternary Pleistocene alluvial gravel mixture with a maximum particle size greater than 1 m, which is considered ultra-large coarse-grained soil as defined by the technical standards for the hydropower and water conservancy industry. The method for determining the shear strength parameters specifically includes the following steps:

[0068] Step S1-1: In the gravel-boulder mixed soil (cemented coarse-grained soil with super-large particle size), select gravel soil with a maximum particle size of ≤30 mm between the boulders, and use the groove method to take an original sample.

[0069] The original sample is a cube, measuring 20 cm × 20 cm × 20 cm. Six samples were collected, numbered Y1, Y2, Y3, Y4, Y5, and Y6. After collection, the original cube samples were wrapped with tape and placed in a sample box. Foam was used to fill the space between the sample and the inner wall of the box to prevent changes in the original bonding structure during transportation.

[0070] Step S1-2: The original sample transported back to the laboratory is subjected to a direct shear test. The direct shear test adopts the horizontal push method, and the vertical pressure is set to 0.

[0071] Through the indoor horizontal push method direct shear test, 6 cohesion C values ​​of 6 original samples can be obtained. p Data, respectively C p1 =126kPa, C p2 =108kPa, C p3 =118kPa, C p4 =129kPa, C p5 =124kPa, C p6 =138kPa.

[0072] Step S1-3: Calculate the average cohesion C of the original sample pm ,

[0073] Calculate the standard deviation σ of the original sample cohesion,

[0074] Analyze the rationality of the test data: perform data rationality check according to 3 times the standard deviation, C pm -3σ=93kPa,C pm +3σ=154kPa, the 6 cohesion C values ​​obtained by the direct shear test using the horizontal push method in step S1-2 p The data are all within the range of [93kPa, 154kPa] and are all reasonable.

[0075] Calculate the coefficient of variation of the cohesion of the original sample δ,

[0076] Calculate the statistical correction coefficient Ψ of the original sample cohesion, Ψ = 1-0.826δ = 0.932.

[0077] Calculate the standard value of cohesion C of the original sample pk , C pk =ΨC pm=115kPa.

[0078] Step S2-1: For the pebble-boulder mixed soil (cemented coarse-grained soil with super-large particle size), 6 groups of disturbed samples are taken. The groups are numbered R1, R2, R3, R4, R5, and R6, with 4 samples in each group, for a total of 6 groups and 24 samples.

[0079] Large stones with a particle size of more than 30 mm were screened out from each sample on site. The mass of a single sample after screening out the large stones was 52.4 kg to 78.2 kg.

[0080] Step S2-2: Each disturbed sample transported back to the laboratory is prepared into a specimen using a similar gradation method in accordance with the relevant technical standards of the hydropower and water conservancy industry.

[0081] Indoor vertical pressure direct shear tests were carried out in groups. The vertical pressures of the four specimens in each group were 200kPa, 400kPa, 600kPa and 800kPa respectively, and the vertical pressure difference was 200kPa.

[0082] Through the indoor vertical pressure direct shear test, each group of disturbed samples can obtain a cohesion C d and an internal friction angle φ d Data. Cohesion C of R1, R2, R3, R4, R5, and R6 groups d C d1 =37kPa, C d2 =39kPa, C d3 =32kPa, C d4 =35kPa, C d5 =35kPa, C d6 =38kPa, internal friction angle They are

[0083] Step S2-3: Analyze only the internal friction angle data obtained from the vertical pressure direct shear test in the disturbance chamber.

[0084] Calculate the average internal friction angle of the disturbed sample

[0085] Calculate the standard deviation σ of the internal friction angle of the disturbance sample,

[0086] Analyze the rationality of the test data: perform data rationality check according to 3 times the standard deviation, Step S2-2 Six internal friction angles obtained by vertical pressure direct shear test The data are all within the range of [34.4 degrees, 40.2 degrees], and the data are all reasonable.

[0087] Calculate the coefficient of variation δ of the internal friction angle of the disturbance sample,

[0088] Calculate the statistical correction coefficient Ψ of the internal friction angle of the disturbed sample, Ψ = 1-0.826δ = 0.979.

[0089] Calculate the standard value of the internal friction angle of the disturbed sample

[0090] Step S3: The original sample cohesion standard value C pk , Standard value of internal friction angle of disturbance sample As the shear strength parameters of cemented super-large coarse-grained soil, cohesion C, internal friction angle Right now:

[0091] The shear strength parameter of the gravel mixed soil (cemented super-large coarse-grained soil) at this site is cohesion C=C pk =115kPa, internal friction angle

[0092] The shear strength parameter values ​​of the cemented, oversized coarse-grained soil of this embodiment are shown in Table 1 below. Comparing the results of a large-scale, in-situ shear test (cohesion 120 kPa, internal friction angle 36.4 degrees), the cohesion of the cemented, oversized coarse-grained soil determined in this embodiment of the present invention has a relative error of 4.2% and an absolute error of -5 kPa, and a relative error of 0.3% and an absolute error of 0.1 degrees for the internal friction angle, which are small and can meet engineering requirements.

[0093] Table 1

[0094]

[0095] In addition, a group of on-site in-situ large-scale shear tests were conducted on a construction site in Tibet, and the methods of the embodiments of the present invention were used to conduct experimental studies respectively, and the test costs and construction periods were compared. As a result, the cost of the on-site in-situ large-scale shear test was about 600,000 yuan, and the site preparation, sample preparation, and test time were 2 months. The sampling, transportation, and test costs of the method of the embodiment of the present invention were about 60,000 yuan, and the sample preparation and test time were less than 1 month. In comparison, the method of the embodiment of the present invention has the advantages of accurate results, cost savings, and shortened test period. At the same time, it can also avoid the safety hazards caused by the need to excavate deep pits and pile heavy loads in on-site in-situ tests.

[0096] A method for determining the shear strength parameters of cemented, ultra-large coarse-grained soil based on comprehensive indoor testing, provided by an embodiment of the present invention, has been successfully applied at the Zala Hydropower Station in the Tibet Autonomous Region (the first large-scale hydropower station with an installed capacity exceeding 100 kW to be started in Tibet), and has been promoted and applied in the preliminary geological surveys of several large-scale hydropower projects, such as the Yuqu River Bitu Hydropower Station and the Zhongbo Hydropower Station in Tibet. Through construction excavation and specialized on-site large-scale shear tests (the on-site large-scale shear tests were conducted in accordance with the "Standard for Geotechnical Test Methods" GB / T50123-2019 and the "Test Procedure for Coarse-Grained Soil for Hydropower and Water Conservancy Projects" DL / T5356, and considering the larger maximum particle size of coarse-grained soil, the test block size specified in the regulations was increased from 30 cm to 50 cm.), the method of the embodiment of the present invention has the advantages of accurate results, cost savings, and shortened testing time. It also avoids the safety hazards posed by the need to excavate deep pits and pile heavy loads in on-site in-situ tests.

[0097] In addition, any details not described in the embodiments of the present invention are prior art.

[0098] The above embodiments merely illustrate several implementations of the present invention, and while their descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the present invention. It should be noted that a person skilled in the art would be able to make numerous modifications and improvements without departing from the spirit of the present invention, all of which fall within the scope of protection of the present invention. Therefore, the scope of protection of the present invention shall be determined by the appended claims.

Claims

1. A method for determining the shear strength parameters of cemented coarse-grained soil with large particle size, characterized in that: The following steps are involved: Take the original sample; Conducting an indoor direct shear test using the horizontal push method on the original sample to obtain multiple cohesion data; Processing the plurality of cohesion data to obtain a standard value of the original cohesion; Take disturbance samples; Performing an indoor vertical pressure direct shear test on the disturbance sample to obtain a plurality of internal friction angle data; Processing the plurality of internal friction angle data to obtain a standard value of the disturbance sample internal friction angle; The standard value of the cohesion of the original sample and the standard value of the internal friction angle of the disturbed sample are determined as the shear strength parameters of the cemented super-large coarse-grained soil, and the maximum particle size of the soil particles of the cemented super-large coarse-grained soil exceeds 200 mm.

2. The method for determining the shear strength parameters of cemented super-large coarse-grained soil according to claim 1, characterized in that: The standard value of the original sample cohesion is calculated according to the following method: Calculate the average value C of the multiple cohesion data pm and standard deviation σ, each of the cohesion data in [C pm -3σ, C pm +3σ] range; Calculate the coefficient of variation of cohesion of the original sample Calculate the statistical correction coefficient of cohesion of the original sample Ψ = 1-0.826δ; Calculate the standard value of cohesion C of the original sample pk =ΨC pm .

3. The method for determining the shear strength parameters of cemented super-large coarse-grained soil according to claim 1, characterized in that: The standard value of the internal friction angle of the disturbance sample is calculated according to the following method: Calculate the average value of multiple internal friction angle data and standard deviation σ, each of the internal friction angle data in within the scope; Calculation of the coefficient of variation of the internal friction angle of the disturbed sample Calculate the statistical correction coefficient of the internal friction angle of the disturbed sample Ψ = 1-0.826δ; Calculate the standard value of the internal friction angle of the disturbance sample 4. The method for determining the shear strength parameters of cemented super-large coarse-grained soil according to claim 1, wherein: The original sample is gravel soil with a maximum soil particle size of ≤30 mm.

5. The method for determining the shear strength parameters of cemented coarse-grained soil with super-large particle size according to claim 4, characterized in that: The original sample is in a cubic shape, with a sample size of 20cm×20cm×20cm, and the number of samples taken is ≥6 pieces.

6. The method for determining the shear strength parameters of cemented coarse-grained soil with super-large particle size according to claim 1, characterized in that: When sampling the disturbed sample, large stones with a particle size greater than 30 mm in each sample are screened out, and the mass of each sample after screening out the large stones is not less than 50 kg.

7. The method for determining the shear strength parameters of cemented super-large coarse-grained soil according to claim 6, characterized in that: The disturbed sample is a sample prepared by a similar gradation method.

8. The method for determining the shear strength parameters of cemented coarse-grained soil with super-large particle size according to claim 7, characterized in that: The disturbance samples include multiple groups, each group includes multiple samples, and the difference in vertical pressure applied between the multiple samples in each group is 200 kPa.

9. The method for determining the shear strength parameters of cemented super-large coarse-grained soil according to claim 8, characterized in that: The disturbance samples include 6 groups, each group includes 4 samples, and the vertical pressures of the 4 samples in each group are 200 kPa, 400 kPa, 600 kPa, and 800 kPa respectively.

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