Coarse-particle salinized soil dissolving and sinking performance evaluation method and system

Abstract

The invention relates to the technical field of special soil engineering geological characteristic analysis and evaluation, in particular to a coarse-particle salinized soil dissolving and sinking performance evaluation method and system.The method comprises the steps that firstly, the stratigraphic layering condition of a target site is obtained, and an engineering geological profile is drawn; taking a representative soil sample from each soil layer of the profile, and measuring the volume of the soil sample by adopting a liquid drainage method; calculating the volume and volume fraction of the soluble salt through a soluble salt analysis test; and determining the average solution subsidence coefficient of the soil sample based on the volume fraction of the soluble salt, calculating the total solution subsidence amount through a layered summation method, and evaluating the solution subsidence grade of the salinized soil foundation. According to the method, through systematic engineering geology survey, indoor test and parameter calculation, rapid quantitative evaluation of the solution sinking characteristic of the salinized soil foundation is achieved, a scientific basis is provided for engineering design and construction, and the method has the advantages of being simple, convenient, high in operability and reliable in result, is suitable for engineering geology evaluation scenes of various salinized soil areas, and has wide application prospects. The method is especially suitable for the melt subsidence evaluation of a coarse-particle salinized soil site in which an undisturbed sample cannot be taken.

Description

Technical Field

[0001] This invention relates to the field of engineering geological property analysis and evaluation technology for special soils, specifically to a method and system for evaluating the solubility of coarse-grained saline soils. Background Technology

[0002] Saline soils are widely distributed in my country, but their planar distribution is uneven, with significant differences in the degree of salt accumulation and composition. Due to their unique engineering geological properties, they have a significant impact on engineering construction. When saline soils are soaked in water, the crystalline salts in the soil are dissolved and carried away by seepage. Under stress, the soil structure deteriorates, and the loss of material components causes soil deformation and subsidence, which is the solubility of saline soils. Solubility has become one of the serious problems causing engineering construction on saline soil sites.

[0003] Currently, the evaluation of the collapsibility of saline soil or the determination of its collapsibility amount are based on the collapsibility coefficient, which is determined by laboratory compression tests or field immersion load tests. However, for coarse-grained saline soil, it is difficult to obtain undisturbed soil samples for laboratory tests, while field immersion load tests are expensive, complex, and time-consuming, resulting in numerous inconveniences and low engineering applicability. Therefore, there is an urgent need for a simple method to estimate the collapsibility coefficient of coarse-grained saline soil and evaluate its collapsibility to meet the needs of engineering construction, especially the needs of site investigation for coarse-grained saline soil. Summary of the Invention

[0004] The technical problem to be solved by the present invention is to provide a method and system for evaluating the solubility of coarse-grained saline soil, which addresses the shortcomings of the prior art and solves the technical problems of complex testing process, high cost and long construction period when evaluating saline soil by field immersion load test.

[0005] The objective of this invention is achieved through the following technical solutions: In a first aspect, the present invention provides a method for evaluating the solubility of coarse-grained saline soil, comprising: Obtain the stratigraphic stratification of the target site, and obtain an engineering geological profile based on the stratigraphic stratification. Representative soil samples were taken from each soil layer in the aforementioned engineering geological profile; The volume of each representative soil sample was determined using the drainage method; The mass of soluble salts in each representative soil sample was determined, and the volume and volume fraction of soluble salts were obtained based on the mass of soluble salts in each representative soil sample. The average solution collapse coefficient of the soil layer of a specified thickness corresponding to this representative soil sample is determined based on the volume fraction of easily soluble salts. The average solution coefficient is used to evaluate the solution level of the saline soil foundation in the target site.

[0006] As a further improvement of the present invention, the engineering geological profile includes material composition at different depths, particle size distribution characteristics, uniformity, stratification characteristics of different material compositions, as well as salt enrichment characteristics and salt-bearing layer morphology characteristics.

[0007] As a further improvement of the present invention, representative soil samples are taken from each soil layer in the engineering geological profile, including: The representative sampling refers to the soil sample taken covering the target site and representing various soil layers with different characteristics in the engineering geological profile; When the sampling depth is less than 5.0m, the sampling interval shall not exceed 0.5m; When the sampling depth is 5.0~10.0m, the sampling interval is 1.0~2.0m; When the sampling depth is greater than 10m, the sampling interval is 2.0~3.0m.

[0008] As a further improvement of the present invention, the method of determining the volume of each representative soil sample by the drainage method includes: The soil sample is crushed to a set particle size range, a representative soil sample of a set weight is obtained, dried to constant weight, cooled to room temperature, and the mass of the representative soil sample restored to room temperature is weighed. The volume of a representative soil sample of known mass is obtained by measuring a predetermined volume of experimental liquid.

[0009] As a further improvement of the present invention, the mass of readily soluble salts in each representative soil sample is determined, and the volume and volume fraction of readily soluble salts are obtained based on the mass of readily soluble salts in each representative soil sample, including: Soluble salt analysis was performed on representative soil samples with known mass using geotechnical testing methods to obtain the composition and mass of the soluble salts. The volume of the soluble salt is calculated based on its mass and corresponding density. The volume of soluble salts is calculated based on the mass and corresponding density of the soluble salts, and the volume fraction of soluble salts is calculated based on the volume of soluble salts and the volume of a representative soil sample.

[0010] As a further improvement of the present invention, the experimental liquid is mineral oil of a set purity, and the mineral oil is pure paraffin oil or industrial-grade white oil.

[0011] As a further improvement of the present invention, the average solution collapse coefficient of the soil layer with the specified thickness is:

[0012] In the formula, m The number of representative soil samples from a given soil layer. The average solution collapse coefficient of a certain soil layer. For the first i The volume of a soil sample. For the first i The volume of soluble salts in a soil sample.

[0013] As a further improvement of the present invention, evaluating the solution level of saline soil foundation in the target site based on the average solution coefficient includes: The total solution collapse amount of the target site is obtained by summing the average solution collapse coefficients of representative soil samples from each layer; the solution collapse level of the saline soil foundation is evaluated based on the total solution collapse amount.

[0014] As a further improvement of the present invention, the total amount of solution trapping is:

[0015] In the formula, The total solution subsidence of the saline soil foundation at the target site; For the first j The average solution collapse coefficient of the soil layer; For the first j The thickness of the soil layer; The number of layers of saline soil in the target site.

[0016] Secondly, the present invention provides a system for evaluating the solubility of coarse-grained saline soil, comprising: The data acquisition module acquires the stratigraphic stratification of the target site and obtains an engineering geological profile based on the stratigraphic stratification. The sampling module takes representative soil samples from each soil layer in the engineering geological profile to obtain representative soil samples from each soil layer. The soluble salt volume calculation module uses the drainage method to determine the volume of each representative soil sample, determines the mass of the corresponding soluble salt through soluble salt analysis in geotechnical tests, and obtains the volume and volume fraction of the soluble salt based on the mass of the soluble salt in each representative soil sample. The evaluation module determines the average solution collapse coefficient of a soil layer of a set thickness based on the volume fraction of easily soluble salts; and evaluates the solution collapse level of the saline soil foundation in the target site based on the average solution collapse coefficient.

[0017] The beneficial effects of this invention are as follows: This invention provides a method for evaluating the solubility of coarse-grained saline soil. By obtaining the stratigraphic stratification of the target site to form an engineering geological profile, it ensures that the basic data for subsequent sampling and analysis accurately reflects the engineering characteristics of the target site. Representative soil samples are taken from each soil layer in the engineering geological profile to ensure the typicality of subsequent test samples and avoid data deviation. The volume of each representative soil sample is determined using the drainage method. The composition and mass of soluble salts are determined through soluble salt analysis, and then the volume and volume fraction of soluble salts are calculated. This step realizes the soluble salt content through the correlation calculation between volume and mass. The quantitative characterization of quantities; the average solution collapse coefficient of the corresponding set thickness soil layer is determined based on the volume fraction of easily soluble salts, directly linking the content of easily soluble salts with the solution collapse characteristics of the soil, avoiding the errors of multi-parameter indirect calculation in traditional methods; finally, the solution collapse level of saline soil foundation is evaluated based on the average solution collapse coefficient, forming a complete step from engineering geological investigation to solution collapse level evaluation. Each step works in sequence and synergistically, realizing the accuracy, objectivity and process-oriented operation of the solution collapse level evaluation of saline soil foundation. Compared with the multi-step indirect calculation or experience judgment method in the existing technology, the reliability and repeatability of the evaluation results are significantly improved. Attached Figure Description

[0018] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0019] Figure 1 This is a flowchart of a method for evaluating the solubility of coarse-grained saline soil according to the present invention; Figure 2 This is a flowchart of step S3 of the present invention; Figure 3 This is a flowchart of step S4 of the present invention; Figure 4 This is a schematic diagram of a method for evaluating the solubility of coarse-grained saline soil according to the present invention; Among them, 1. Target site; 2. Strata; 3. Representative soil sample. Detailed Implementation

[0020] To make the objectives and technical solutions of this invention clearer and easier to understand, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. The specific embodiments described herein are for illustrative purposes only and are not intended to limit the invention.

[0021] The technical solution of the present invention will be clearly and completely described below with reference to the accompanying drawings and specific embodiments. The described embodiments are only some embodiments of the present invention, and not all embodiments.

[0022] Example 1 Currently, the standard evaluation of the solubility of saline soil requires the solubility coefficient, which is determined by indoor compression tests or field immersion load tests. However, it is difficult to obtain undisturbed soil samples for coarse-grained saline soil, and field immersion tests are expensive, complex, and time-consuming, resulting in low engineering applicability. Therefore, this embodiment provides a simple and feasible evaluation method. This embodiment provides a method for evaluating the solubility of coarse-grained saline soil, including the following steps: obtaining the stratigraphic stratification of the target site and obtaining an engineering geological profile based on the stratigraphic stratification; taking representative soil samples from each soil layer in the engineering geological profile; determining the volume of each representative soil sample using the drainage method; determining the mass of the corresponding soluble salt through soluble salt analysis, and obtaining the volume and volume fraction of the soluble salt based on the mass of the soluble salt in each representative soil sample; determining the average solubility coefficient of the corresponding soil layer of a set thickness based on the volume fraction of the soluble salt; and evaluating the solubility level of the saline soil foundation in the target site based on the average solubility coefficient.

[0023] This embodiment obtains the stratigraphic stratification of the target site through exploration and draws an engineering geological profile, providing a basis for subsequent sampling and analysis. Representative soil samples ensure that the soil samples can reflect the overall soil stratification characteristics of the site. The volume of soil samples is accurately determined by the drainage method, and the mass, volume, and volume fraction of soluble salts are analyzed by combining geotechnical tests. Based on reasonable assumptions, the volume fraction of soluble salts is correlated with the solution collapse coefficient to calculate the average solution collapse coefficient. Finally, the total solution collapse amount is obtained by the stratified summation method, realizing the evaluation of the solution collapse level of saline soil foundation. This method overcomes the pain point of not being able to take undisturbed soil samples in coarse-grained saline soil sites, and eliminates the need for complex and expensive on-site immersion tests. The solution collapse coefficient and total solution collapse amount can be quickly calculated through simple sampling, drainage method volume measurement, and soluble salt analysis. The evaluation process is clear, simple to operate, efficient and fast, which significantly reduces the cost and construction period of coarse-grained saline soil solution collapse evaluation and improves engineering applicability.

[0024] When obtaining information on the stratigraphic layers of the target site, exploration methods such as drilling, well drilling, and trenching are employed to describe in detail the material composition, particle size distribution, and uniformity of strata at different depths. This information is then used to create a complete engineering geological profile, clearly showing the depth range, thickness, and distribution patterns of each soil layer. Representative sampling of each soil layer must be conducted at the intervals specified in the standards, ensuring that the soil samples cover the entire target site and reflect the characteristics of different soil layers. Each soil sample should weigh between 300 and 500 grams and be sealed in a double-layered polyethylene bag after sampling, ensuring the air is completely removed. When determining soil sample volume using the displacement method, the soil sample is first crushed to a maximum particle size of within 5 mm. 100-200 g of the sample is weighed, dried at low temperature to constant weight, and cooled to room temperature. The mass is then measured using an electronic balance with an accuracy of 0.01 g. A clean, dry 250 mL or 500 mL graduated cylinder is filled with high-purity mineral oil (such as pure paraffin oil) at a constant temperature. After reading the initial volume, the soil sample is slowly placed into the cylinder and completely submerged. The final volume is then read; the soil sample volume is the difference between the two volumes. When determining the mass of soluble salts through soluble salt analysis, the soil sample after volume measurement is dried at low temperature to remove oil and reach constant weight, ensuring that the error between the oil-removed and dried mass does not exceed 0.5%. Then, soluble salt analysis is performed using conventional geotechnical testing to determine the soluble salt content and calculate the mass. When calculating the volume based on the soluble salt mass, a weighted density is determined according to the salt composition of the soluble salts, and the density formula is used. V = m / ρ (in V The volume of the readily soluble salt. m For the quality of easily soluble salts, ρ The volume fraction is calculated by converting the weighted density to volume, and is the ratio of the volume of soluble salts to the volume of the soil sample. When determining the average solution collapse coefficient based on the volume fraction of soluble salts, it is assumed that the volume loss due to immersion is solely caused by the dissolution of soluble salts, and that in-situ confined solution collapse manifests only as settlement. For a stratum with m representative soil samples, the average solution collapse coefficient is calculated using a formula. When evaluating the solution collapse level based on the average solution collapse coefficient, the total solution collapse amount is first calculated using the stratified summation method, and then the level is evaluated according to the "Technical Specification for Construction in Saline Soil Areas" (GB / T 50942-2014). An electronic balance with an accuracy of 0.01g is selected to ensure the accuracy of mass measurement. In practical applications, other models with higher accuracy can also be selected, and this application embodiment does not limit this. A graduated cylinder of 250mL or 500mL is selected to accommodate the volume measurement of soil samples of different masses. In practical applications, other specifications can also be selected, and this application embodiment does not limit this.

[0025] The engineering geological profile includes the material composition at different depths, the particle size distribution, homogeneity, and stratification characteristics of different material components, as well as salt enrichment characteristics and salt-bearing layer morphology. When drawing the engineering geological profile, a comprehensive coverage of material composition, particle size distribution, homogeneity, stratification characteristics, and salt-related features is ensured. This provides precise target areas for subsequent representative sampling, guaranteeing that the soil samples taken specifically reflect areas with different salt distributions and stratigraphic characteristics, and providing comprehensive and accurate basic data for soluble salt analysis and solution collapse evaluation.

[0026] Furthermore, the material composition at different depths refers to the specific constituent materials of the soil at different depths within the target site, such as the proportions of various materials like sand, gravel, and clay. This is determined through drilling and sampling, followed by particle size analysis. The particle size distribution characteristics of different material components refer to the distribution ratio of particles of different sizes within each material. This is determined using a standard sieve analysis method, specifically by passing the soil sample through a series of standard sieves with different apertures, weighing the mass of soil sample retained on each sieve, calculating the mass fraction of particles within each size range, and thus obtaining the particle size distribution curve. Homogeneity refers to the degree of consistency in material composition and particle size distribution within the same depth or soil layer. This is achieved by repeatedly sampling and analyzing different locations within the same soil layer, comparing the material composition and particle size distribution results of each sample. Smaller differences indicate better homogeneity, while larger differences indicate poorer homogeneity. Stratification characteristics refer to the layering of strata based on differences in material composition and particle size distribution, including the depth range, thickness, and the degree of distinctness of interlayer interfaces of each soil layer. This is determined through continuous drilling records and sampling analysis. Salt enrichment characteristics refer to the accumulation of soluble salts in strata at different depths, such as the distribution of areas where the content of soluble salts is significantly higher at certain depths than at other depths. This is determined by measuring the salt content of soil samples at each depth using soluble salt analysis tests. The morphological characteristics of salt-bearing layers refer to the spatial distribution shape and extent of soil layers with high salt content, such as horizontal layers or lenticular shapes. This is determined by combining the salt analysis results from multiple exploration points with the stratigraphic stratification.

[0027] Representative sampling of each soil layer in the engineering geological profile is conducted, further including: when the sampling depth is less than 5.0m, the sampling interval is no more than 0.5m; when the sampling depth is 5.0~10.0m, the sampling interval is 1.0~2.0m; when the sampling depth is greater than 10m, the sampling interval is 2.0~3.0m. A representative soil sample refers to a soil sample that covers the target site and represents various soil layers with different characteristics in the engineering geological profile. Setting scientifically reasonable sampling intervals according to different depths ensures that a sufficient number of soil samples are obtained within different depth ranges, while also ensuring that the soil samples cover the target site and encompass various characteristic soil layers, making the collected soil samples sufficiently representative and providing a reliable sample basis for subsequent analysis and evaluation.

[0028] The volume of representative soil samples was determined using the displacement method, which included: crushing the soil samples to a predetermined particle size range, obtaining a representative soil sample of a predetermined weight, drying it to constant weight, cooling it to room temperature, and weighing the representative soil sample after it had returned to room temperature; measuring the mass of a known representative soil sample using a predetermined volume of experimental liquid; and obtaining the volume of the representative soil sample. The displacement method accurately determines the soil sample volume by utilizing the principle that the volume displaced by the experimental liquid equals the volume of the soil sample.

[0029] The volume and volume fraction of soluble salts are obtained based on the mass of soluble salts in each soil sample. This process includes: analyzing soluble salts using geotechnical testing methods on a representative soil sample with known mass to determine the composition of soluble salts; determining the mass of soluble salts; calculating the volume of soluble salts based on their mass and corresponding density; and calculating the volume fraction of soluble salts based on the volume of soluble salts and the volume of the representative soil sample. By accurately analyzing the composition and mass of soluble salts using geotechnical testing methods, calculating the volume of soluble salts using weighted densities corresponding to the components, and then combining this with the soil sample volume to obtain the volume fraction, the scientific validity and accuracy of the calculation of soluble salt-related parameters are ensured.

[0030] The average solution sinking coefficient is:

[0031] In the formula, m The number of representative soil samples from a given soil layer. The average solution collapse coefficient of a certain stratum. For the first i The volume of a soil sample. For the first i The volume of soluble salts in a soil sample. Based on the reasonable assumption that the volume loss during immersion is only caused by the dissolution of soluble salts and that the solution collapse is only manifested as settlement under in-situ confined conditions, the volume fraction of soluble salts can represent the solution collapse coefficient. By weighted averaging of the volume of soluble salts and the volume of soil samples from multiple representative soil samples, the average solution collapse coefficient of the formation is obtained, which reflects the overall solution collapse characteristics of the formation.

[0032] The experimental liquid was mineral oil of a predetermined purity, using either pure paraffin oil or industrial-grade white oil. Utilizing the chemical stability and insolubility of high-purity mineral oil in readily soluble salts, the reaction between the soil sample and the experimental liquid, or the dissolution of readily soluble salts, was avoided during soil sample volume determination. This ensured that the soil sample volume remained stable throughout the measurement process, and the volume was accurately obtained using the displacement method.

[0033] Based on a representative soil sample of known mass, soluble salt analysis was performed using conventional geotechnical testing methods (such as the gravimetric method). The specific steps were as follows: The soil sample of known mass was placed in a beaker, an appropriate amount of distilled water was added, and the mixture was stirred thoroughly and allowed to stand to soak, allowing the soluble salts in the soil sample to fully dissolve in the water. The soaked solution was then filtered through quantitative filter paper to remove soil particle impurities. The filtered solution was placed in an evaporating dish and evaporated to dryness at a low temperature (60-80℃) to obtain soluble salt crystals. The specific composition of the soluble salts, such as sodium chloride, potassium chloride, and sodium sulfate, was determined by analyzing the composition of the crystals. When determining the soluble salt content, the mass of the evaporated soluble salt crystals was weighed; this mass is the mass of the soluble salts in the soil sample. If the soil sample was not completely dissolved or the filtration was incomplete, the test needed to be repeated.

[0034] The evaluation of the solution collapse level of the saline soil foundation in the target site based on the average solution collapse coefficient includes: summing the average solution collapse coefficients of representative soil samples from each layer to obtain the total solution collapse amount of the target site; and evaluating the solution collapse level of the saline soil foundation based on the total solution collapse amount.

[0035] The total amount of solution is:

[0036] In the formula, The total solution subsidence of the saline soil foundation at the target site; For the first j The average solution collapse coefficient of the soil layer; For the first j The thickness of the soil layer; The number of layers of saline soil in the target site.

[0037] By combining the average solution collapse coefficient and thickness of each soil layer using the layered summation method, the total solution collapse amount of the target site is calculated. The total solution collapse amount can comprehensively reflect the degree of solution collapse of the saline soil in the entire site. Then, according to the standard, the total solution collapse amount is correlated with the solution collapse level to achieve a scientific evaluation of the solution collapse level of the saline soil foundation.

[0038] Example 2 This embodiment provides a specific implementation method for evaluating the solubility of coarse-grained saline soil. For example... Figure 1 As shown, the evaluation method includes the following steps: S1: Explore the target site using drilling, wells, trenches, and other methods to describe the stratigraphic stratification and draw engineering geological profiles, including the material composition, particle size distribution, uniformity, and stratification characteristics at different depths. At the same time, observe the salt enrichment characteristics and the morphological characteristics of salt-bearing layers.

[0039] S2: Take representative soil samples from each soil layer according to the sampling intervals required by the specifications. When the depth is less than 5.0m, the interval should not be greater than 0.5m; when the depth is 5.0~10.0m, the interval should be 1.0~2.0m; when the depth is greater than 10m, the interval should be 2.0~3.0m. The soil samples taken should cover the target site and be representative of various soil layers with different characteristics in the engineering geological profile. Sampling should be done using tools such as shovels to obtain representative soil samples that conform to the actual strata on site. Each sample can be 300~500g according to quality control. After sampling, immediately wrap the sample in a double-layer polyethylene sealed bag, remove the air, and then seal it.

[0040] S3: The volume of the soil sample is determined using the drainage method. For example... Figure 2 As shown, it specifically includes: S301: Crush a representative soil sample to control the maximum particle size within 5mm. Weigh 100-200g of the soil sample evenly, dry it at low temperature to constant weight, cool it to room temperature, and weigh the dry soil using an electronic balance (accuracy 0.01g). ; S302: Slowly add an appropriate amount of a specific, temperature-controlled liquid medium (high-purity mineral oil, such as pure paraffin oil or industrial-grade white oil) to a clean, dry graduated cylinder (250mL / 500mL), and record the initial volume. Slowly and evenly place the soil sample into the graduated cylinder, ensuring it is completely submerged, and read the volume. ; S303: The volume of the soil sample equals the volume of the displaced liquid. Calculate the soil sample volume. .

[0041] S4: Determine the mass of easily soluble salts in a soil sample and convert it to volume and volume fraction. For example... Figure 3 As shown, it specifically includes: S401: After measuring the volume of the soil sample, dry it at a low temperature to remove oil until constant weight, cool it to room temperature, and weigh the soil sample after oil removal. (and The error should not exceed 0.5%; otherwise, the process should restart from step S301. S402: Analyze soluble salts using conventional geotechnical testing methods to obtain the salt composition of soluble salts, determine the soluble salt content (mass method), and calculate the mass of soluble salts in the soil sample. ; S403: Calculating the volume of easily soluble salts using the density formula:

[0042] in: The mass of the easily soluble salt; This represents the volume of the readily soluble salt. This is a weighted density of readily soluble salts, determined based on their salt composition (densities of common readily soluble salts). , , , , , , ); S404: Calculate the volume fraction of soluble salts in a soil sample: .

[0043] S5: Based on the finite reasonable assumptions, the volume fraction of easily soluble salts in a soil sample can represent the solution collapse coefficient of the soil layer corresponding to the representative soil sample, and thus determine the average solution collapse coefficient of the soil layer. For those m The average solution collapse coefficient of a certain stratum in a representative soil sample is:

[0044] in: The average solution collapse coefficient of a certain stratum; For the first i The volume of the soil sample; For the first i The volume of soluble salts in a soil sample.

[0045] S6: Calculate the total solution collapse of the target site using the layered summation method;

[0046] in: The total solution subsidence of the saline soil foundation at the target site; For the first j The average solution collapse coefficient of the soil layer; For the first j The thickness of the soil layer; The number of layers of saline soil at the target site, among which Non-collapseable soil layers are not included.

[0047] S7: Evaluate the solution collapse level of saline soil foundations, that is, evaluate them according to the provisions of the "Technical Code for Building Construction in Saline Soil Areas" (GB / T50942-2014), specifically as follows: When the soil surface temperature reaches 1 mm, the foundation karstification level is classified as Class I weak karstification. When the soil surface temperature reaches 100 mm, the soil sag level is classified as Grade II, moderate sag. When the soil surface temperature reaches 100 mm, the foundation karstification level is Class III, a strong karstification.

[0048] In practical applications, a simulation program can be constructed. This program uses the methods described above to directly derive the required solution collapse coefficient by importing experimental data from soluble salt analysis and stratigraphic layering data. The specific calculation program can be completed using any programming software such as Excel or Python; this application does not impose any specific limitations.

[0049] The above description is not intended to limit the present invention, nor is the present invention limited to the examples given above. Any equivalent structural or procedural transformations made based on the description and drawings of the present invention, or any direct or indirect applications in other related technical fields, are similarly included within the scope of protection of the present invention.

[0050] Example 3 Based on the methods for evaluating the solubility of coarse-grained saline soil in Examples 1 and 2, this example provides a system for evaluating the solubility of coarse-grained saline soil, which includes: The data acquisition module acquires the stratigraphic stratification of the target site and obtains an engineering geological profile based on the stratigraphic stratification. The sampling module performs representative sampling of each soil layer in the engineering geological profile to obtain representative soil samples of each soil layer. The soluble salt volume calculation module uses the displacement method to determine the volume of each representative soil sample, determines the mass of the corresponding soluble salt through soluble salt analysis experiments, and obtains the volume and volume fraction of the soluble salt based on the mass of the soluble salt in each representative soil sample. The evaluation module determines the average solution collapse coefficient of a soil layer of a set thickness based on the volume fraction of easily soluble salts; and evaluates the solution collapse level of the saline soil foundation in the target site based on the average solution collapse coefficient.

[0051] The above description is merely an embodiment of this application and is not intended to limit the scope of protection of this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the scope of protection of this application.

Claims

1. A method for evaluating the solubility of coarse-grained saline soil, characterized in that, include: Obtain the stratigraphic stratification of the target site, and obtain an engineering geological profile based on the stratigraphic stratification. Representative soil samples were taken from each soil layer in the aforementioned engineering geological profile; The volume of each representative soil sample was determined using the drainage method; The mass of soluble salts in each representative soil sample was determined, and the volume and volume fraction of soluble salts were obtained based on the mass of soluble salts in each representative soil sample. The average solution collapse coefficient of the soil layer of a specified thickness corresponding to this representative soil sample is determined based on the volume fraction of easily soluble salts. The average solution coefficient is used to evaluate the solution level of the saline soil foundation in the target site.

2. The method for evaluating the solubility of coarse-grained saline soil according to claim 1, characterized in that, The engineering geological profile includes material composition at different depths, particle size distribution characteristics, uniformity, stratification characteristics of different material components, as well as salt enrichment characteristics and salt-bearing layer morphology.

3. The method for evaluating the solubility of coarse-grained saline soil according to claim 1, characterized in that, Representative soil samples were taken from each soil layer in the aforementioned engineering geological profile, including: The representative sampling refers to the soil sample taken covering the target site and representing various soil layers with different characteristics in the engineering geological profile; When the sampling depth is less than 5.0m, the sampling interval shall not exceed 0.5m; When the sampling depth is 5.0~10.0m, the sampling interval is 1.0~2.0m; When the sampling depth is greater than 10m, the sampling interval is 2.0~3.0m.

4. The method for evaluating the solubility of coarse-grained saline soil according to claim 1, characterized in that, The determination of the volume of each representative soil sample using the drainage method includes: The soil sample is crushed to a set particle size range, a representative soil sample of a set weight is obtained, dried to constant weight, cooled to room temperature, and the mass of the representative soil sample restored to room temperature is weighed. The volume of a representative soil sample of known mass is obtained by measuring a predetermined volume of experimental liquid.

5. The method for evaluating the solubility of coarse-grained saline soil according to claim 1, characterized in that, The mass of readily soluble salts in each representative soil sample was determined, and the volume and volume fraction of the readily soluble salts were obtained based on the mass of readily soluble salts in each representative soil sample, including: Soluble salt analysis was performed on representative soil samples with known mass using geotechnical testing methods to obtain the composition and mass of the soluble salts. The volume of the soluble salt is calculated based on its mass and corresponding density. The volume fraction of soluble salts was calculated based on the volume of soluble salts and the volume of a representative soil sample.

6. The method for evaluating the solubility of coarse-grained saline soil according to claim 4, characterized in that, The experimental liquid is mineral oil of a set purity, and the mineral oil used is pure paraffin oil or industrial-grade white oil.

7. The method for evaluating the solubility of coarse-grained saline soil according to claim 1, characterized in that, The average solution collapse coefficient of the soil layer with the specified thickness is: In the formula, m The number of representative soil samples from a given soil layer. The average solution collapse coefficient of a certain soil layer. For the first i The volume of a soil sample. For the first i The volume of soluble salts in a soil sample.

8. The method for evaluating the solubility of coarse-grained saline soil according to claim 1, characterized in that, The evaluation of the sag level of saline soil foundation in the target site based on the average sag coefficient includes: The total solution subsidence amount of the target site is obtained by summing the average solution subsidence coefficients of the soil layers with a set thickness; the solution subsidence level of the saline soil foundation is evaluated based on the total solution subsidence amount.

9. The method for evaluating the solubility of coarse-grained saline soil according to claim 8, characterized in that, The total amount of solution trap is: In the formula, The total solution subsidence of the saline soil foundation at the target site; For the first j The average solution collapse coefficient of the soil layer; For the first j The thickness of the soil layer; The number of layers of saline soil in the target site.

10. A system for evaluating the solubility of coarse-grained saline soil, characterized in that, include: The data acquisition module acquires the stratigraphic stratification of the target site and obtains an engineering geological profile based on the stratigraphic stratification. The sampling module takes representative soil samples from each soil layer in the engineering geological profile to obtain representative soil samples from each soil layer. The soluble salt volume calculation module uses the drainage method to determine the volume of each representative soil sample, determines the mass of the corresponding soluble salt through soluble salt analysis in geotechnical tests, and obtains the volume and volume fraction of the soluble salt based on the mass of the soluble salt in each representative soil sample. The evaluation module determines the average solution collapse coefficient of the corresponding soil layer based on the volume fraction of easily soluble salts; and evaluates the solution collapse level of the saline soil foundation in the target site based on the average solution collapse coefficient.

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