Method and system for rapidly testing moisture content of gypsum soil based on alcohol combustion method

Abstract

The invention discloses a method and a system for rapidly testing the moisture content of gypsum soil based on an alcohol combustion method. Comprising the following steps: firstly, carrying out data analysis on water content test data measured by adopting an alcohol combustion method and water content test data measured by adopting a standard low-temperature drying method so as to determine the fast-measured water content of gypsum soil measured by adopting the alcohol combustion method; the mapping relation between the moisture content and the standard moisture content of the gypsum soil measured by adopting a standard drying method is obtained. Then, rapidly measuring the moisture content of the to-be-measured gypsum soil by adopting an alcohol combustion method to obtain the rapidly measured moisture content corresponding to the to-be-measured gypsum soil, and determining the standard moisture content corresponding to the to-be-measured gypsum soil according to the mapping relation between the rapidly measured moisture content and the standard moisture content. The method realizes rapid measurement of the moisture content of the gypsum soil by an alcohol combustion method, overcomes the problem that the alcohol combustion method in the current specification is not suitable for the determination of the moisture content of the gypsum soil, reduces the test time of the moisture content of the gypsum soil, and improves the detection efficiency of the moisture content of the gypsum soil.

Description

Technical Field

[0001] The invention relates to the technical field of analyzing ground materials using a special method, and in particular to a method and system for quickly testing the moisture content of gypsum soil based on an alcohol combustion method. Background Art

[0002] Soil moisture content is a key parameter in geotechnical engineering, which directly affects the engineering mechanical properties of rock and soil. In actual engineering, in order to control the construction quality of artificial fill and obtain good engineering mechanical properties, the fill is usually compacted near the optimal moisture content, and the compaction degree or compaction coefficient is used as the key parameter for compaction quality control. It can be seen that the determination of soil moisture content is not only an important part of geotechnical analysis, but also one of the key technologies for construction quality control.

[0003] The test methods for soil moisture content can be divided into direct method and indirect method. The direct methods include drying method, sand bath method, alcohol combustion method, infrared method, etc., and the indirect methods include matrix suction test method, ray method, dielectric property method, shared tracer method, remote sensing method, etc. The test results of the direct method are accurate and reliable. Among them, the drying method is the standard method for determining the moisture content of soil in the current specification. For example, the "JTG 3430-2020 Highway Geotechnical Test Procedure" requires that ordinary soil samples be dried at a constant temperature of 105-110℃ for 6-8 hours, and the moisture content is calculated by weighing. The alcohol combustion method and sand bath method are suitable for quick and easy determination of soil moisture content.

[0004] Since gypsum is a soft sulfate mineral composed of calcium sulfate dihydrate, with the chemical formula of CaSO4·2H2O, when heated at 65℃, dihydrate gypsum begins to release structural water, but the dehydration speed is relatively slow. At around 107℃, when the water vapor pressure reaches 971mmHg, the dehydration speed increases rapidly. As the temperature continues to rise, the dehydration speed increases. At 170-190℃, dihydrate gypsum dehydrates at a very fast speed to become α-hemihydrate gypsum or β-hemihydrate gypsum, with the chemical formula of CaSO4·0.5H2O. In industry, raw gypsum is heated to 150℃ and dehydrated to make mature gypsum.

[0005] Therefore, the "JTG 3430-2020 Highway Geotechnical Test Procedure" stipulates that the temperature of gypsum soil containing gypsum should be controlled within the range of 60-70°C, and the drying time should not be less than 24 hours. The "JTG 3441-2024 Highway Engineering Inorganic Binder Stabilized Material Test Procedure" requires that soil samples containing gypsum should be dried at a temperature not exceeding 80°C, and the drying time should be extended. For gypsum soil, in order to avoid the loss of bound water, traditional drying methods use relatively low drying temperatures, which will inevitably lead to an extension of the test time, affect the test efficiency, and increase time and economic costs.

[0006] The temperature of the alcohol combustion method is about 300°C, and the temperature of the sand bath method is 350-600°C. The temperature of both methods is higher than the dehydration temperature of gypsum, which causes the loss of bound water, resulting in the measurement data of the moisture content of gypsum soil being too large and the results being distorted. Therefore, current specifications, such as "JTG 3430-2020 Highway Geotechnical Test Procedures" and "JTG 3441-2024 Highway Engineering Inorganic Binder Stabilized Material Test Procedures", require that the sand bath method and alcohol combustion method shall not be used to measure the moisture content of gypsum soil. Summary of the invention

[0007] In view of the shortcomings of the prior art, the present invention proposes a method and system for quickly testing the moisture content of gypsum soil based on the alcohol combustion method, which can use the alcohol combustion method to quickly measure the moisture content of gypsum soil. The specific technical solution is as follows:

[0008] In a first aspect, a method for quickly testing the moisture content of gypsum soil based on an alcohol combustion method is provided. In a first achievable manner of the first aspect, the method comprises:

[0009] Determine the mapping relationship between the quick moisture content of gypsum soil measured by the alcohol combustion method and the standard moisture content measured by the standard drying method;

[0010] The quick-measured moisture content of the gypsum soil to be tested is obtained by measuring the alcohol combustion method, and the standard moisture content corresponding to the gypsum soil to be tested is determined through a mapping relationship between the quick-measured moisture content and the standard moisture content.

[0011] In combination with the first implementable manner of the first aspect, in a second implementable manner of the first aspect, determining a mapping relationship between the quick-measured moisture content and the standard moisture content includes:

[0012] The quick-test moisture content and standard moisture content of each gypsum soil sample measured by the alcohol combustion method and the drying method are obtained, and the moisture content of each gypsum soil sample is different;

[0013] The fitting function between the quick-measured moisture content and the standard moisture content is determined by performing function fitting on the quick-measured moisture content and the standard moisture content of all the gypsum soil samples.

[0014] In combination with the second implementable manner of the first aspect, in a third implementable manner of the first aspect, obtaining a quick moisture content of a gypsum soil sample measured by an alcohol combustion method includes:

[0015] Get the total mass m of the heat-resistant container after the gypsum soil sample is placed 1i , and the total mass m of the heat-resistant container after adding alcohol and burning until the gypsum soil sample has no lumps 2i ;

[0016] Combined with the total mass m 1i、Heat-resistant container mass m 3i and total mass m 2i , calculate the quick moisture content of the gypsum soil sample.

[0017] In combination with the second implementable manner of the first aspect, in a fourth implementable manner of the first aspect, obtaining a quick moisture content of a gypsum soil sample measured by an alcohol combustion method includes:

[0018] The moisture content of multiple groups of gypsum soil samples measured by the alcohol combustion method was obtained, and the moisture content of all gypsum soil samples was statistically analyzed, and the average value was taken as the quick-test moisture content corresponding to the gypsum soil sample.

[0019] In combination with the fourth implementable manner of the first aspect, in a fifth implementable manner of the first aspect, statistical analysis is performed on the moisture content of all gypsum soil samples, including:

[0020] Based on the 3σ principle, outliers in the moisture content of all gypsum soil samples were eliminated.

[0021] In combination with the fifth possible implementation of the first aspect, in a sixth possible implementation of the first aspect, statistical analysis is performed on the moisture content of all gypsum soil samples, including:

[0022] After eliminating the abnormal data, the moisture content of the gypsum soil sample measured by the alcohol combustion method is re-obtained for supplementation.

[0023] In the second aspect, a rapid testing system for moisture content of gypsum soil based on an alcohol combustion method is provided, which comprises:

[0024] a relationship determination module configured to determine a mapping relationship between a quick-measured moisture content of gypsum soil measured by an alcohol combustion method and a standard moisture content measured by a standard drying method;

[0025] The rapid measurement module is configured to obtain the rapid moisture content of the gypsum soil to be tested measured by the alcohol combustion method, and determine the standard moisture content corresponding to the gypsum soil to be tested through the mapping relationship between the rapid moisture content and the standard moisture content.

[0026] In a third aspect, a method for quickly testing the moisture content of gypsum soil based on an alcohol combustion method is provided. In a first achievable manner of the third aspect, the method comprises:

[0027] preparing a plurality of gypsum soil samples with different moisture contents;

[0028] The moisture content of each gypsum soil sample was measured by alcohol combustion method and standard drying method respectively, and the quick moisture content and standard moisture content corresponding to each gypsum soil sample were obtained;

[0029] By measuring the quick-test moisture content and the standard moisture content corresponding to all gypsum soil samples, a mapping relationship between the quick-test moisture content and the standard moisture content of the gypsum soil is determined;

[0030] The alcohol combustion method is used to measure the quick moisture content of the gypsum soil to be tested, and the standard moisture content of the gypsum soil to be tested is determined through the mapping relationship between the quick moisture content and the standard moisture content.

[0031] In combination with the first implementable manner of the third aspect, in a second implementable manner of the third aspect, the mass of the gypsum soil sample is not less than 2 kilograms and the stewing time is not less than 24 hours.

[0032] In combination with the first implementable manner of the third aspect, in a third implementable manner of the third aspect, measuring the moisture content of the gypsum soil sample by the alcohol combustion method includes:

[0033] Weigh the mass of the heat-resistant container m 3i , and the total mass m of the gypsum soil sample placed in the heat-resistant container 1i ;

[0034] Continuously adding alcohol into the heat-resistant container until a free liquid surface appears in the heat-resistant container;

[0035] Ignite the alcohol, wait for the alcohol to burn out and cool for a certain period of time, crush the gypsum soil lumps, add alcohol again and ignite, and repeat this process until there are no gypsum soil lumps in the heat-resistant container;

[0036] Weigh the total mass m of the heat-resistant container 2i , combined with the total mass m 1i 、Heat-resistant container mass m 3i and total mass m 2i , calculate the moisture content of the gypsum soil sample.

[0037] Beneficial effect: The method and system for rapid testing the moisture content of gypsum soil based on the alcohol combustion method of the present invention are based on the moisture content of gypsum soil rapidly measured by the alcohol combustion method. By determining the correlation between the moisture content test results of the gypsum soil low-temperature drying method and the alcohol combustion method, the standard moisture content of the gypsum soil can be accurately obtained, thereby overcoming the problem that the alcohol combustion method in the current specification is not suitable for the determination of the moisture content of gypsum soil, reducing the test time of the moisture content of gypsum soil, and improving the detection efficiency of the moisture content of gypsum soil. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] In order to more clearly illustrate the specific implementation of the present invention, the following will briefly introduce the drawings required for use in the specific implementation. In all the drawings, each element or part is not necessarily drawn according to the actual scale.

[0039] Figure 1A flow chart of a method for quickly testing the moisture content of gypsum soil based on an alcohol combustion method provided by an embodiment of the present invention;

[0040] Figure 2 A system block diagram of a rapid testing system for moisture content of gypsum soil based on an alcohol combustion method provided by an embodiment of the present invention;

[0041] Figure 3 A flow chart of a method for quickly testing the moisture content of gypsum soil based on an alcohol combustion method provided by another embodiment of the present invention;

[0042] Figure 4 is the drying characteristic curve of gypsum soil;

[0043] Figure 5 is the drying rate curve of gypsum soil;

[0044] Figure 6 This is the fitting relationship curve between the standard moisture content of a typical gypsum soil and the quick moisture content measured by the alcohol combustion method. DETAILED DESCRIPTION

[0045] The following embodiments of the technical solution of the present invention are described in detail in conjunction with the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solution of the present invention, and are therefore only used as examples, and cannot be used to limit the protection scope of the present invention.

[0046] like Figure 1 The flowchart of the rapid test method for moisture content of gypsum soil based on alcohol combustion method is shown in the figure. The test method includes:

[0047] Step 1, determining a mapping relationship between the quick moisture content of gypsum soil measured by the alcohol combustion method and the standard moisture content measured by the standard drying method;

[0048] Step 2: Obtain the quick moisture content of the gypsum soil to be tested measured by the alcohol combustion method, and determine the standard moisture content corresponding to the gypsum soil to be tested through a mapping relationship between the quick moisture content and the standard moisture content.

[0049] Specifically, first, data analysis can be performed on the moisture content test data obtained by the alcohol combustion method and the moisture content test data measured by the standard low-temperature drying method, so as to determine the mapping relationship between the quick moisture content of the gypsum soil measured by the alcohol combustion method and the standard moisture content of the gypsum soil measured by the standard drying method. Then, the alcohol combustion method can be used to quickly measure the moisture content of the gypsum soil to be tested, and the quick moisture content corresponding to the gypsum soil to be tested can be obtained, and the standard moisture content corresponding to the gypsum soil to be tested can be determined through the mapping relationship between the quick moisture content and the standard moisture content. Thus, the alcohol combustion method can be used to quickly measure the moisture content of the gypsum soil, which overcomes the problem that the alcohol combustion method in the current specification is not suitable for the determination of the moisture content of the gypsum soil, reduces the test time of the moisture content of the gypsum soil, and improves the detection efficiency of the moisture content of the gypsum soil.

[0050] In this embodiment, optionally, in step 1, determining a mapping relationship between the quick-measured moisture content and the standard moisture content includes:

[0051] The quick-test moisture content and standard moisture content of each gypsum soil sample measured by the alcohol combustion method and the drying method are obtained, and the moisture content of each gypsum soil sample is different;

[0052] The fitting function between the quick-measured moisture content and the standard moisture content is determined by performing function fitting on the quick-measured moisture content and the standard moisture content of all the gypsum soil samples.

[0053] Specifically, the mapping relationship between the quick-test moisture content and the standard moisture content can be determined by function fitting. Specifically, first, the quick-test moisture content and standard moisture content corresponding to gypsum soil samples with different moisture contents can be obtained through multiple groups of actual tests. The actual test includes measuring the moisture content of two identical gypsum soil samples by the alcohol combustion method and the standard drying method, respectively, to obtain the quick-test moisture content and standard moisture content of the gypsum soil samples. Then, function fitting is performed based on the quick-test moisture content and standard moisture content obtained by all actual test experiments, and the fitting function obtained by fitting can characterize the mapping relationship between the moisture content test results of the gypsum soil low-temperature drying method and the alcohol combustion method.

[0054] In this embodiment, optionally, obtaining the quick moisture content of the gypsum soil sample measured by the alcohol combustion method includes:

[0055] Get the total mass m of the heat-resistant container after the gypsum soil sample is placed 1i , and the total mass m of the heat-resistant container after adding alcohol and burning until the gypsum soil sample has no lumps 2i ;

[0056] Combined with the total mass m 1i 、Heat-resistant container mass m 3i and total mass m 2i, calculate the quick moisture content of the gypsum soil sample.

[0057] Specifically, the quick test moisture content of the gypsum soil sample can be determined based on the mass change before and after the alcohol is burned. Specifically, after the gypsum soil sample is placed in a heat-resistant container, a weighing device can be used to measure the total mass m of the heat-resistant container after the gypsum soil sample is placed. 1i , and add alcohol to the heat-resistant container and burn it until the gypsum cloth in the heat-resistant container is obviously agglomerated, and then use a weighing device to measure the total mass m of the heat-resistant container 2i Finally, according to the total mass m 1i 、Heat-resistant container mass m 3i and total mass m 2i The quick test moisture content of the gypsum soil sample can be calculated. The specific calculation formula is as follows:

[0058]

[0059] Wherein, i is the gypsum soil sample number, i=1, 2, 3…N.

[0060] In this embodiment, optionally, obtaining the quick moisture content of the gypsum soil sample measured by the alcohol combustion method includes:

[0061] The moisture content of multiple groups of gypsum soil samples measured by the alcohol combustion method was obtained, and the moisture content of all gypsum soil samples was statistically analyzed, and the average value was taken as the quick-test moisture content corresponding to the gypsum soil sample.

[0062] Specifically, the moisture content is the ratio of the mass of water attached between soil particles to the dry weight of soil particles. When the alcohol combustion method is used, the bound water in the gypsum particles in the gypsum soil will be partially lost. At the same time, due to the short heating time and the agglomeration of some particles, the attached water may not be completely evaporated. The measured moisture content has systematic errors and poor stability. In order to reduce errors, improve test accuracy, and ensure the validity of the mapping relationship obtained by fitting. Multiple identical gypsum soil samples can be prepared and measured using the alcohol combustion method to obtain multiple groups of moisture content data and take the average value as the quick moisture content corresponding to the gypsum soil sample.

[0063] In this embodiment, optionally, a statistical analysis is performed on the moisture content of all gypsum soil samples, including: eliminating abnormal values ​​in the moisture content of all the acquired gypsum soil samples based on the 3σ principle.

[0064] Specifically, in order to further improve the test accuracy and ensure the validity of the mapping relationship obtained by fitting, after obtaining the moisture content data of all gypsum soil samples measured by the alcohol combustion method, the abnormal values ​​in the moisture content data obtained can be eliminated based on the 3σ principle to ensure the accuracy of the quick moisture content calculated subsequently.

[0065] Specifically, first, calculate the mean and standard deviation of all moisture content data obtained. The specific calculation formula is as follows:

[0066]

[0067]

[0068] Among them, w bik is the moisture content data of gypsum soil samples, and n is the number of gypsum soil samples of the same type.

[0069] Then, outliers greater than μ+3σ or less than μ-3σ in the moisture content data obtained are removed. In order to ensure that there is enough data to participate in the calculation of the quick moisture content of the gypsum soil sample, after removing the outliers, the alcohol combustion method can be used to measure the same gypsum soil sample again, and the moisture content data obtained by the measurement can be added to the data set for calculating the quick moisture content.

[0070] This process is repeated until there are no abnormal values ​​in the data set used to calculate the quick moisture content, and the average value of the data set can be obtained as the quick moisture content.

[0071] like Figure 2 The system block diagram of the gypsum soil moisture content rapid test system based on the alcohol combustion method shown in the figure, the test system includes:

[0072] a relationship determination module configured to determine a mapping relationship between a quick-measured moisture content of gypsum soil measured by an alcohol combustion method and a standard moisture content measured by a standard drying method;

[0073] The rapid measurement module is configured to obtain the rapid moisture content of the gypsum soil to be tested measured by the alcohol combustion method, and determine the standard moisture content corresponding to the gypsum soil to be tested through the mapping relationship between the rapid moisture content and the standard moisture content.

[0074] Specifically, the test system includes a relationship determination module and a rapid measurement module. Among them, the relationship determination module can perform data analysis on the moisture content test data obtained by the alcohol combustion method and the moisture content test data measured by the standard low-temperature drying method, so as to determine the mapping relationship between the rapid moisture content of the gypsum soil measured by the alcohol combustion method and the standard moisture content of the gypsum soil measured by the standard drying method. The rapid measurement module can obtain the rapid moisture content of the gypsum soil to be tested obtained by the alcohol combustion method, and determine the standard moisture content corresponding to the gypsum soil to be tested through the mapping relationship between the rapid moisture content and the standard moisture content. Thus, the alcohol combustion method is used to quickly measure the moisture content of gypsum soil, which overcomes the problem that the alcohol combustion method in the current specification is not suitable for the determination of the moisture content of gypsum soil, reduces the test time of the moisture content of gypsum soil, and improves the detection efficiency of the moisture content of gypsum soil.

[0075] like Figure 3 The flowchart of the rapid test method for moisture content of gypsum soil based on alcohol combustion method is shown in the figure. The test method includes:

[0076] Step S1, preparing a plurality of gypsum soil samples with different moisture contents;

[0077] Step S2, respectively measuring the moisture content of each gypsum soil sample by using an alcohol combustion method and a standard drying method, and obtaining a quick moisture content and a standard moisture content corresponding to each gypsum soil sample;

[0078] Step S3, determining the mapping relationship between the quick-measured moisture content and the standard moisture content of the gypsum soil by measuring the quick-measured moisture content and the standard moisture content corresponding to all gypsum soil samples;

[0079] Step S4, using the alcohol combustion method to measure the quick moisture content of the gypsum soil to be tested, and determining the standard moisture content of the gypsum soil to be tested through the mapping relationship between the quick moisture content and the standard moisture content.

[0080] Specifically, first, multiple gypsum soil samples with 3 to 5 different moisture contents can be prepared for the target gypsum soil. Then, the moisture contents of these gypsum soil samples are measured by the alcohol combustion method and the standard drying method, respectively, to obtain the quick moisture content and standard moisture content corresponding to the gypsum soil samples with different moisture contents. After that, the mapping relationship between the quick moisture content of the gypsum soil measured by the alcohol combustion method and the standard moisture content of the gypsum soil measured by the standard drying method can be determined by fitting all the quick moisture contents and standard moisture contents obtained. Finally, the quick moisture content of the gypsum soil to be tested can be measured by the alcohol combustion method, and the standard moisture content corresponding to the gypsum soil to be tested can be determined by the mapping relationship between the quick moisture content and the standard moisture content. Thus, the alcohol combustion method is used to quickly measure the moisture content of the gypsum soil, which overcomes the problem that the alcohol combustion method in the current specification is not suitable for the determination of the moisture content of the gypsum soil, reduces the test time of the moisture content of the gypsum soil, and improves the detection efficiency of the moisture content of the gypsum soil.

[0081] In this embodiment, optionally, the mass of the gypsum soil sample is not less than 2 kg and the stewing time is not less than 24 hours.

[0082] Specifically, when preparing gypsum soil samples with different moisture contents, in order to avoid errors caused by re-sampling due to insufficient sample quality, the sample quality should be sufficient during sample preparation. Through test analysis, it was found that when the gypsum soil sample is not less than 2 kg, the test requirements for the gypsum soil sample quality can be met at one time, avoiding errors caused by multiple sample preparations. At the same time, the duration of the simmering time is not less than 24 hours, which can ensure that the water is fully distributed in the gypsum soil and improve the accuracy of the moisture content test results.

[0083] In this embodiment, optionally, in step 2, measuring the moisture content of the gypsum soil sample by the alcohol combustion method includes:

[0084] Weigh the mass of the heat-resistant container m 3i , and the total mass m of the gypsum soil sample placed in the heat-resistant container 1i ;

[0085] Continuously adding alcohol into the heat-resistant container until a free liquid surface appears in the heat-resistant container;

[0086] Ignite the alcohol, wait for the alcohol to burn out and cool for a certain period of time, crush the gypsum soil lumps, add alcohol again and ignite, and repeat this process until there are no gypsum soil lumps in the heat-resistant container;

[0087] Weigh the total mass m of the heat-resistant container 2i , combined with the total mass m 1i 、Heat-resistant container mass m 3i and total mass m 2i , calculate the moisture content of the gypsum soil sample.

[0088] Specifically, first, a weighing device can be used to weigh the mass of the heat-resistant container, and after the gypsum soil sample is placed in the heat-resistant container, the total mass of the heat-resistant container after the gypsum soil sample is placed in the heat-resistant container is weighed. Then, alcohol is injected into the heat-resistant container until a free liquid surface appears in the heat-resistant container. Afterwards, an igniter is used to ignite the alcohol in the heat-resistant container, and the flame in the heat-resistant container is waited for to naturally extinguish. After cooling for a period of time, the gypsum soil lumps in the heat-resistant container are crushed, and alcohol is added to the heat-resistant container again to ignite. This process is repeated until no obvious gypsum soil lumps appear in the heat-resistant container. Finally, the total mass of the heat-resistant container can be weighed, and the moisture content of the gypsum soil sample can be calculated by combining the total mass weighed before and after the combustion of the heat-resistant container and the mass of the heat-resistant container.

[0089] Since the moisture content is the ratio of the mass of attached water between soil particles to the dry weight of soil particles, when the alcohol combustion method is used, the bound water in the gypsum particles in the gypsum soil will be partially lost. At the same time, due to the short heating time and the agglomeration of some particles, the attached water may not be completely evaporated, and the measured moisture content has systematic errors and poor stability. In order to reduce the error, improve the test accuracy, and ensure the validity of the mapping relationship obtained by fitting. The above-mentioned method for measuring moisture content can be used to measure the moisture content of each gypsum soil sample of the same type to construct a data set. Then, based on the 3σ principle, the outliers of the data set are eliminated to ensure the accuracy of the data set. After eliminating the outliers, the alcohol combustion method is used again to measure the same gypsum soil sample, and the measured moisture content data is added to the data set. Finally, the mean corresponding to the data set is obtained as the quick test moisture content corresponding to the gypsum soil sample.

[0090] After obtaining the quick test moisture content and standard moisture content corresponding to gypsum soil samples with different moisture contents, the quadratic function can be used to fit the mapping relationship between the quick test moisture content and the standard moisture content. Through a large amount of data analysis, it is found that the quadratic function is better in fitting the relationship between the standard moisture content and the quick test moisture content measured by the alcohol combustion method, with high goodness of fit and no overfitting.

[0091] As verified by examples, the main physical properties and gypsum content of a typical gypsum soil are shown in Table 1, and its standard moisture content is measured according to the embodiment of the present invention.

[0092] project Natural moisture content <![CDATA[CaSO4·2H2O]]> proportion <![CDATA[d max / mm]]> <![CDATA[C U ]]> <![CDATA[C C ]]> <![CDATA[Plastic limit w P > <![CDATA[Liquid limit w L > name Numeric 14.8％ 80％ 2.195 0.25 6 2 30.1％ 41.5％ Low liquid limit silt

[0093] Table 1 Main physical and chemical properties of a typical gypsum soil

[0094] The gypsum soil shown in Table 1 was prepared into gypsum soil with different moisture contents. After being stuffed for 24 hours, it was dried at 60°C. The weight of the soil sample was measured every 1 hour. The obtained drying characteristic curve and drying rate curve are shown in Figure 4 , Figure 5 As shown. Figure 4 , Figure 5 It can be seen that as the drying time increases, the moisture content and drying rate of the gypsum soil decrease continuously. The moisture content of the gypsum soil with different initial moisture contents decreases rapidly in the first 5 hours; but after drying for 10 hours, the gypsum soil is still not completely dry, and after drying for 24 hours, the gypsum soil is completely dry.

[0095] The gypsum soil shown in Table 1 was prepared into gypsum soil with different moisture contents, and the moisture content was tested by the drying method (60°C) and the alcohol combustion method in the embodiment of the present invention, and the quadratic function was fitted. The results are as follows: Figure 6 The fitting function between the standard value of moisture content measured by drying method and the moisture content measured by alcohol combustion method is w0 = -1.3267w b 2 +1.8142w b -0.1332, and its goodness of fit is adjusted to 0.9951, which shows a good fitting effect.

[0096] The gypsum soil shown in Table 1 was used to prepare gypsum soils with other moisture contents to be tested, and the moisture content was tested using the alcohol combustion method in the embodiment of the present invention. The standard moisture content of the gypsum soil to be tested was calculated based on the fitting relationship between the standard value of the moisture content and the moisture content measured by the alcohol combustion method, and compared with the standard value of the moisture content obtained by the drying method (60°C) in the embodiment of the present invention. The results are shown in Table 2.

[0097]

[0098] Table 2 Comparison and review of test results of alcohol combustion method for a typical gypsum soil

[0099] As shown in Table 2, the inter-group error of the moisture content obtained by the present invention is 0.27%, and the result stability is good. Compared with the drying method, the error of the calculation result of the present invention is 0.44%, and the relative error is 3.3%, which is less than the engineering allowable error of 5%, and has good calculation accuracy. Based on the above analysis, the rapid test method for the moisture content of gypsum soil based on the alcohol combustion method provided by the present invention is reasonable and feasible.

[0100] The above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein by equivalents. These modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present invention, and they should all be included in the scope of the claims and specification of the present invention.

Claims

1. A rapid test method for moisture content of gypsum soil based on alcohol combustion method, characterized in that: include: Determine the mapping relationship between the quick moisture content of gypsum soil measured by the alcohol combustion method and the standard moisture content measured by the standard drying method; The quick-measured moisture content of the gypsum soil to be tested is obtained by measuring the alcohol combustion method, and the standard moisture content corresponding to the gypsum soil to be tested is determined through a mapping relationship between the quick-measured moisture content and the standard moisture content.

2. The method for rapid testing moisture content of gypsum soil based on alcohol combustion method according to claim 1, characterized in that: Determine the mapping relationship between the quick test moisture content and the standard moisture content, including: The quick-test moisture content and standard moisture content of each gypsum soil sample measured by the alcohol combustion method and the drying method are obtained, and the moisture content of each gypsum soil sample is different; The fitting function between the quick-measured moisture content and the standard moisture content is determined by performing function fitting on the quick-measured moisture content and the standard moisture content of all the gypsum soil samples.

3. The method for rapid testing moisture content of gypsum soil based on alcohol combustion method according to claim 2, characterized in that: Get quick moisture content measurements of gypsum soil samples using the alcohol combustion method, including: Get the total mass m of the heat-resistant container after the gypsum soil sample is placed 1i , and the total mass m of the entire heat-resistant container after adding alcohol and burning until the gypsum soil sample has no lumps 2i ; Combined with the total mass m 1i 、Heat-resistant container mass m 3i and total mass m 2i , calculate the quick moisture content of the gypsum soil sample.

4. The method for rapid testing moisture content of gypsum soil based on alcohol combustion method according to claim 2, characterized in that: Get quick moisture content measurements of gypsum soil samples using the alcohol combustion method, including: The moisture content of multiple groups of gypsum soil samples measured by the alcohol combustion method was obtained, and the moisture content of all gypsum soil samples was statistically analyzed, and the average value was taken as the quick test moisture content corresponding to the gypsum soil sample.

5. The method for rapid testing moisture content of gypsum soil based on alcohol combustion method according to claim 4, characterized in that: The moisture content of all the gypsum soil samples was statistically analyzed, including: Based on the 3σ principle, outliers in the moisture content of all gypsum soil samples were eliminated.

6. The method for rapid testing moisture content of gypsum soil based on alcohol combustion method according to claim 5, characterized in that: Statistical analysis of the moisture content of all gypsum soil samples, including: After eliminating abnormal data, the moisture content of the gypsum soil sample measured by the alcohol combustion method is re-obtained for supplementation.

7. A rapid testing system for moisture content of gypsum soil based on alcohol combustion method, characterized in that: include: a relationship determination module configured to determine a mapping relationship between a quick moisture content of gypsum soil measured by an alcohol combustion method and a standard moisture content measured by a standard drying method; The rapid measurement module is configured to obtain the rapid moisture content of the gypsum soil to be tested measured by the alcohol combustion method, and determine the standard moisture content corresponding to the gypsum soil to be tested through the mapping relationship between the rapid moisture content and the standard moisture content.

8. A rapid test method for moisture content of gypsum soil based on alcohol combustion method, characterized in that: include: preparing a plurality of gypsum soil samples with different moisture contents; The moisture content of each gypsum soil sample was measured by alcohol combustion method and standard drying method respectively, and the quick moisture content and standard moisture content corresponding to each gypsum soil sample were obtained; By measuring the quick-test moisture content and the standard moisture content corresponding to all gypsum soil samples, a mapping relationship between the quick-test moisture content and the standard moisture content of the gypsum soil is determined; The alcohol combustion method is used to measure the quick moisture content of the gypsum soil to be tested, and the standard moisture content of the gypsum soil to be tested is determined through the mapping relationship between the quick moisture content and the standard moisture content.

9. The method for rapid testing moisture content of gypsum soil based on alcohol combustion method according to claim 8, characterized in that: The mass of the gypsum soil sample is not less than 2 kg and the stewing time is not less than 24 hours.

10. The method for rapid testing moisture content of gypsum soil based on alcohol combustion method according to claim 8, characterized in that: The alcohol combustion method is used to measure the moisture content of gypsum soil samples, including: Weigh the mass of the heat-resistant container m 3i , and the total mass m of the gypsum soil sample placed in the heat-resistant container 1i ; Continuously adding alcohol into the heat-resistant container until a free liquid surface appears in the heat-resistant container; Ignite the alcohol, wait for the alcohol to burn out and cool for a certain period of time, crush the gypsum soil lumps, add alcohol again and ignite, and repeat this process until there are no gypsum soil lumps in the heat-resistant container; Weigh the total mass m of the heat-resistant container 2i , and combined with the total mass m 1i 、Heat-resistant container mass m 3i and total mass m 2i , calculate the moisture content of the gypsum soil sample.

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