Large-size model sample continuous loading consolidation test device and method for earthen archaeological site construction process research

Abstract

The invention discloses a large-size model sample continuous loading consolidation test device and method for earthen archaeological site construction process research. The device comprises a universal testing machine, a consolidation container, water head saturation equipment and a pore water pressure measurement system, a structural large-size sample is placed in the consolidation container; the universal testing machine is used for applying a vertical load with a constant rate to the structural large-size sample and recording vertical displacement, vertical stress and time; the water head saturation equipment is communicated with the interior of the consolidation container and is used for introducing distilled water into the consolidation container, and a water head saturates the structural large-size sample; and the pore water pressure measuring system is used for recording the change of the pore water pressure at the bottom of the sample in the consolidation process, and calculating and analyzing test data based on a CRS one-dimensional linear consolidation theory. The device solves the problems of difficulty in force application and long time consumption when a large-size sample is subjected to a consolidation test in a traditional geotechnical test, and is suitable for consolidation deformation test research of a model sample constructed by a process in the field of earthen ruins.

Description

Technical Field

[0001] The present invention relates to the technical field of geotechnical tests, and particularly relates to a large-size model specimen continuous loading consolidation test device and method for the research of the construction technology of earthen ruins. Background Art

[0002] The traditional construction technology of earthen ruins is an important object of the research on the protection of earthen ruins. Scientifically understanding the construction technology of earthen ruins and directly applying effective traditional construction technologies to the reinforcement of earthen ruins can make the protected design conform to the original appearance of earthen ruins, which is conducive to the inheritance and development of China's excellent traditional construction technologies. The construction technologies of earthen ruins in China are complex and diverse. Typical raw-earth construction technologies include rammed earth, earth covering, wood / bamboo frame mud wall, straw mud, etc. Due to the use of special construction methods and the addition of different materials during the construction process, earthen ruins constructed by different technologies have special structures. Due to the non-renewability of cultural relics, the research on earthen ruin technologies is carried out in the form of model tests.

[0003] The consolidation deformation of soil is an important aspect for evaluating the stability of buildings. The oedometer test is currently the most commonly used indoor test method for determining the compressibility parameters of soil. A test specimen is cut from an undisturbed soil sample or a remolded soil sample with a metal cutting ring. The size of the cutting ring is generally 80 mm in inner diameter and 20 mm in height. The test specimen is placed in a consolidometer, and the test specimen is loaded in stages through a load transfer plate to complete the consolidation test. However, when studying the construction technology of earthen ruins, the cutting ring samples in the conventional consolidation test cannot truly represent their structural and non-homogeneous properties, and it is necessary to consider the size effect and prepare large-volume model specimens. Stress is a physical quantity related to area. When the volume of the test specimen increases, the compressed area increases, and a larger load is required to meet the consolidation loading requirements. However, in a geotechnical laboratory, whether using a jack reaction support or a lever system, there are great difficulties, and it is not easy to stabilize the vertical load. In addition, the staged loading consolidation test takes a long time. When the volume of the test specimen increases, the deformation time under each stage of load will increase significantly, and the consolidation test time will be even longer. The continuous loading test is a consolidation test method with a mature theory and short time consumption, but it is currently rarely used in geotechnical laboratories.

[0004] Based on the above technical background, there is an urgent need for a device and method for the consolidation test of large-size specimens that is low-cost, easy to operate, and can be realized in a geotechnical laboratory. Summary of the Invention

[0005] In view of this, the purpose of the present invention is to provide a large-size model specimen continuous loading consolidation test device and method for the research of the construction technology of earthen ruins, which solves the problems of difficult force application and long time consumption during the consolidation test of large-size specimens in traditional geotechnical tests, and is applicable to the consolidation deformation test research of construction technology model specimens in the field of earthen ruins.

[0006] The technical solution adopted by the present invention to solve the technical problem is as follows:

[0007] A large-size model specimen continuous loading consolidation test device for the research of earthen site construction technology, comprising: a universal testing machine, a consolidation container, a water head saturation device and a pore water pressure measurement system;

[0008] The consolidation container is placed on the universal testing machine, and a large-size structural specimen is placed inside;

[0009] The universal testing machine is used to apply a vertical load at a constant rate to the large-size structural specimen, and automatically record the vertical displacement, vertical stress and time;

[0010] The water head saturation device is connected to the inside of the consolidation container and is used to introduce distilled water into the inside of the consolidation container to saturate the large-size structural specimen with water head;

[0011] The pore water pressure measurement system records the change of the pore water pressure at the bottom of the specimen during the consolidation process, and calculates and analyzes the test data based on the CRS one-dimensional linear consolidation theory.

[0012] Further, the universal testing machine adopts a floor-standing double-column machine, including a base and an upper functional head. The upper functional head is installed on the base, and there is enough space between the base and the upper functional head to stably place the consolidation container.

[0013] Further, the consolidation container is a steel rectangular box with an open top, a sealed bottom and an inlet valve and a pore water pressure sensor connection port are provided. A permeable stone slab is provided at the bottom end inside the consolidation container, and a filter paper is provided between the permeable stone slab and the lower surface of the large-size structural specimen.

[0014] Further, it further includes a pressure cover. The pressure cover is a double-layer metal plate structure. The total area of the lower metal plate is the same as the bottom area of the consolidation container. The upper metal plate and the lower metal plate are welded distributively by steel bars; a drainage channel is provided inside the middle axis position of the upper metal plate and the lower metal plate, and a drainage valve is provided on the side wall of the upper metal plate.

[0015] Further, a groove is provided at the bottom of the lower metal plate for nesting and placing the permeable stone slab. A filter paper is provided between the permeable stone slab and the upper surface of the large-size structural specimen, and a sealing rubber ring is provided at the edge of the groove.

[0016] Further, the water head saturation device includes a distilled water bucket and a water guide pipe. The distilled water bucket is connected to the inlet valve through the water guide pipe.

[0017] Further, the pore water pressure acquisition device includes a pore water pressure sensor, a data acquisition system, and a computer; the pore water pressure sensor is installed at the position of the pore water pressure sensor connection port, and the pore water pressure sensor is communicatively connected to the computer through the data acquisition system.

[0018] Further, the continuous loading consolidation test of the large-scale structural specimen is divided into a constant strain rate loading stage, a constant stress stage, and a rebound stage.

[0019] A method for continuous loading consolidation test of large-scale model specimens for the study of the construction technology of earthen ruins, comprising the following steps:

[0020] Step S1, place the consolidation container on the universal testing machine, apply vaseline to the inner side wall of the consolidation container, place a permeable stone slab at the bottom of the consolidation container, add distilled water, open the water inlet valve, remove the air at the bottom of the consolidation container, close the water inlet valve after the exhaust is completed, soak the permeable stone slab with distilled water, and place a filter paper on the permeable stone slab;

[0021] Step S2, place the prepared large-scale structural specimen into the consolidation container, or directly prepare the large-scale structural specimen in the consolidation container, place a filter paper on the large-scale structural specimen, place a rubber ring at the edge of the large-scale structural specimen, nest the pressure application cover plate with the permeable stone slab, and place it on the large-scale structural specimen;

[0022] Step S3, control the universal testing machine, apply a vertical pressure of 1 kPa to the specimen, level the large-scale structural specimen, so that the pressure application cover plate is sealed with the large-scale structural specimen;

[0023] Step S4, connect the water inlet valve at the bottom of the consolidation container to the water guide pipe, connect the water guide pipe to the distilled water bucket, provide a water head height of 1 m, saturate the specimen with the water head, and at the same time saturate the pore water pressure sensor probe with high-quality degassed water; after the water starts to flow out and stabilize at the drainage valve of the pressure application cover plate, the specimen saturation is completed, the water inlet valve of the consolidation container is closed, and the pore water pressure sensor is connected to the bottom of the consolidation container;

[0024] Step S5, according to the experimental requirements, set the pressure application program of the universal testing machine: the first stage is the constant strain rate loading stage, continuously load to the expected stress or strain, and the large-scale structural specimen drains unidirectionally at the top; the second stage is the constant load stage, in which the pore water pressure dissipates under the condition of constant vertical deformation; the third stage is the unloading stage, and the large-scale structural specimen unloads at the strain rate equal to that during loading; the universal testing machine can record the vertical stress, strain, time, and pore water pressure.

[0025] The beneficial effects of the present invention:

[0026] (1) The present invention solves the problem that it is difficult to apply load during the consolidation test of large-sized indoor structural specimens, and adopts the constant strain rate consolidation test method. The device is simple, has a high degree of automation, and saves the consolidation test time.

[0027] (2) The load of this consolidation device is applied by a universal testing machine, and a pressure plate is arranged between the universal testing machine and the large-sized structural specimen, so that the vertical load of the specimen can be accurately applied and evenly and stably distributed on the surface of the specimen.

[0028] (3) The consolidation container of this consolidation device is assembled with the universal testing machine, and the size and shape of the consolidation container can be adjusted according to the specific size of the specimen, with a wide range of applications.

[0029] (4) This device can monitor and record the changes of vertical force, displacement and pore water pressure in real time, with accurate data. The acquisition frequency can be adjusted according to requirements, avoiding the error of manual counting. Description of the Drawings

[0030] Figure 1 is a schematic structural diagram of the present invention;

[0031] Figure 2 is a schematic installation structure diagram of the sealing rubber ring of the present invention.

[0032] Among them, in the figure:

[0033] 1 is a universal testing machine, 2 is a consolidation container, 3 is a pressure plate, 4 is a permeable stone, 5 is a filter paper, 6 is a pore water pressure sensor, 7 is a data acquisition system, 8 is a computer, 9 is a water conduit, 10 is a distilled water bucket, 11 is a drainage channel, and 12 is a sealing rubber ring. Specific Embodiments

[0034] To make the objectives, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are some, but not all, of the embodiments of the present invention. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0035] Referring to Figure 1-2 , the present invention provides a large-sized model specimen continuous loading consolidation test device for the research of the construction technology of earthen ruins, including: a universal testing machine 1, a consolidation container 2, a water head saturation device, and a pore water pressure measurement system;

[0036] The consolidation container 2 is placed on the universal testing machine 1, and a large-sized structural specimen is placed inside;

[0037] The universal testing machine 1 is used to apply a vertical load at a constant rate to a large-sized structural specimen and automatically record the vertical displacement, vertical stress, and time;

[0038] The water head saturation device is internally connected to the consolidation container 2 and is used to introduce distilled water into the consolidation container 2 to saturate the large-sized structural specimen with water head;

[0039] The pore water pressure measurement system records the change in the pore water pressure at the bottom of the specimen during consolidation and calculates and analyzes the test data based on the CRS one-dimensional linear consolidation theory.

[0040] The prepared large-sized structural specimen is placed into the consolidation container 2. The consolidation container 2 is placed on the floor-standing universal testing machine 1. After saturating the large-sized structural specimen with water head, the displacement control program of the universal testing machine 1 is started, and an appropriate strain rate is set. A vertical load is applied to the specimen to conduct a constant strain rate loading consolidation test. The universal testing machine 1 records the vertical load and vertical displacement of the specimen, and the pore water pressure measurement system records the pore water pressure at the bottom of the specimen in real time. Based on the CRS one-dimensional consolidation theory, the consolidation coefficient and permeability coefficient of the specimen are calculated.

[0041] The universal testing machine 1 adopts a floor-standing double-column machine, including a base and an upper functional head. The upper functional head is installed on the base, and there is enough space between the base and the upper functional head to stably place the consolidation container 2.

[0042] The consolidation container 2 is a steel rectangular box with an open top, a sealed bottom, and an inlet valve and a pore water pressure sensor connection port are provided. A permeable stone 4 plate is arranged at the bottom end inside the consolidation container 2, and a filter paper 5 is arranged between the permeable stone 4 plate and the lower surface of the large-sized structural specimen.

[0043] The present invention further includes a pressure cover. The pressure cover is a double-layer metal plate structure. The total area of the lower metal plate is the same as the bottom area of the consolidation container 2. The upper metal plate and the lower metal plate are welded distributively by steel bars to ensure that the vertical pressure can be evenly applied to the specimen. A drainage channel 11 is arranged inside the central axis position of the upper metal plate and the lower metal plate, and a drainage valve is arranged on the side wall of the upper metal plate.

[0044] A groove is arranged at the bottom of the lower metal plate for nesting and placing the permeable stone 4 plate. A filter paper 5 is arranged between the permeable stone 4 plate and the upper surface of the large-sized structural specimen, and a sealing rubber ring 12 is arranged at the edge of the groove to ensure the sealing of the specimen during water head saturation.

[0045] The water head saturation device includes a distilled water bucket 10 and a water guide pipe 9. The distilled water bucket 10 is connected to the inlet valve through the water guide pipe 9.

[0046] The pore water pressure acquisition device includes a pore water pressure sensor 6, a data acquisition system 7, and a computer 8; the pore water pressure sensor 6 is installed at the position of the pore water pressure sensor connection port, and the pore water pressure sensor 6 is communicatively connected to the computer 8 through the data acquisition system 7.

[0047] To further optimize the technical solution, the maximum test force of the electronic universal testing machine 1 is 500 kN, and the crossbeam displacement speed range is stepless speed regulation from 0.001 mm / min to 500 mm / min, which can be set arbitrarily to ensure that the requirements for applying test loads are met.

[0048] Place a permeable stone 4 and a filter paper 5 at the bottom of the consolidation container 2, add distilled water, open the bottom water inlet valve, and remove air bubbles. Prepare a large-size specimen according to the test requirements and place it in the consolidation container 2. Place a filter paper 5, a sealing rubber ring 12, a permeable stone 4, and a pressure application cover plate 3 on the upper part of the large-size structural specimen in sequence. The bottom water inlet valve of the consolidation container 2 is connected to a distilled water bucket 10 through a water conduit 9. Open the water inlet valve to saturate the specimen with a water head. The bottom of the consolidation container 2 is connected to the pore water pressure sensor 6 after saturation. Start the universal testing machine 1, set the loading program, and apply a vertical load at a constant rate to the specimen by the universal testing machine 1. The drainage valve on the top pressure application cover plate 3 of the large-size structural specimen drains unidirectionally, and one-dimensional unidirectional drainage consolidation occurs. The universal testing machine 1 can automatically record the vertical displacement, vertical stress, and time. The pore water pressure acquisition system records the change in the pore water pressure at the bottom of the specimen during consolidation. Based on the CRS one-dimensional linear consolidation theory, the test data is calculated and analyzed. The continuous loading consolidation test of the large-size structural specimen is divided into a constant strain rate loading stage, a constant stress stage, and a rebound stage.

[0049] The present invention also provides a method for continuous loading consolidation test of a large-size model specimen for the study of the construction technology of earthen sites, including the following steps:

[0050] Step S1: Place the consolidation container on the universal testing machine, apply vaseline to the inner side wall of the consolidation container, place a permeable stone plate at the bottom of the consolidation container, add distilled water, open the water inlet valve, remove the air at the bottom of the consolidation container, close the water inlet valve after the exhaust is completed, soak the permeable stone plate with distilled water to saturation, and place a filter paper on the permeable stone plate;

[0051] Step S2: Place the prepared large-size structural specimen into the consolidation container, or directly prepare a large-size structural specimen in the consolidation container. Place a filter paper on the large-size structural specimen, place a rubber ring at the edge of the large-size structural specimen, nest the pressure application cover plate with the permeable stone plate, and place it on the large-size structural specimen;

[0052] Step S3: Operate the universal testing machine to apply a vertical pressure of 1 kPa to the specimen, level the large-sized structural specimen, and make the pressure cover plate sealed with the large-sized structural specimen.

[0053] Step S4: Connect the water inlet valve at the bottom of the consolidation container to the water guide pipe, connect the water guide pipe to the distilled water bucket, provide a water head height of 1 m to saturate the specimen with the water head, and at the same time use high-quality degassed water to saturate the pore water pressure sensor probe; after the water starts to flow out from the drainage valve of the pressure cover plate and stabilizes, the specimen saturation ends, close the water inlet valve of the consolidation container, and connect the pore water pressure sensor to the bottom of the consolidation container.

[0054] Step S5: According to the experimental requirements, set the loading program of the universal testing machine: The first stage is the constant strain rate loading stage, continuously load until the expected stress or strain, and the large-sized structural specimen drains unidirectionally at the top; the second stage is the constant load stage, in this stage, the pore water pressure dissipates under the condition of constant vertical deformation; the third stage is the unloading stage, and the large-sized structural specimen unloads under the condition of the strain rate equal to that during loading; the universal testing machine can record the vertical stress, strain, time, and pore water pressure.

[0055] The present invention solves the problem that it is difficult to apply load during the consolidation test of large-sized structural specimens indoors, and adopts the constant strain rate consolidation test method. The device is simple, has a high degree of automation, and saves the consolidation test time. The consolidation load of this consolidation device is applied by the universal testing machine, and a pressure cover plate is arranged between the universal testing machine and the large-sized structural specimen, so that the vertical load of the specimen can be accurately applied and evenly and stably distributed on the specimen surface. The consolidation container of this consolidation device is assembled with the universal testing machine, and the size and shape of the consolidation container can be adjusted according to the specific size of the specimen, and it has a wide range of uses. This device can monitor and record the changes of vertical force, displacement and pore water pressure in real time, the data is accurate, and the acquisition frequency can be adjusted according to the needs, avoiding the error of manual counting.

[0056] Embodiment

[0057] This embodiment is a one-dimensional unidirectional drainage consolidation test study on the typical process - straw-wrapped mud piled wall in the Liangzhu Site. Due to the special structure of the straw-wrapped mud pile, the traditional indoor consolidation test method cannot be used. Therefore, the equipment and method proposed by the present invention are adopted. The size of the test box is 40 cm in length, 30 cm in width, and 30 cm in height.

[0058] (1) Prepare straw-wrapped mud blocks according to the restoration process of archaeologists.

[0059] (2) Apply vaseline to the side wall of the consolidation container, place a permeable stone slab and filter paper at the bottom of the consolidation container, pour in degassed water, and remove the air bubbles at the bottom of the consolidation container.

[0060] (3) Stack the grass-wrapped mud blocks with staggered joints for three layers. After stacking is completed, place filter paper, permeable stones, and sealing rubber rings on the upper part of the specimen.

[0061] (4) Place the pressure application cover plate on the upper permeable stone, start the universal testing machine, make the functional head of the universal testing machine contact the pressure application cover plate, and apply a load of 1 kPa.

[0062] (5) Connect the bottom water inlet valve to the water guide pipe, and perform head saturation through the distilled water bucket until saturation ends when stable water emerges from the drainage channel of the pressure application cover plate.

[0063] (6) Close the bottom water inlet valve, and connect the saturated pore water pressure sensor to the pore water pressure connection port at the bottom of the consolidation container.

[0064] (7) Set the loading program of the universal testing machine, and start the consolidation test. The specimen drains unidirectionally through the drainage valve on the pressure application cover plate at the top. The first stage is the constant strain rate loading stage, and the strain rate is set to 0.04 mm / min. Record the vertical displacement, vertical stress, and pore water pressure at the bottom of the specimen.

[0065] (8) When the vertical stress of the specimen increases to 600 kPa, enter the constant load stage, keep it at 600 kPa unchanged until the pore water pressure is completely dissipated.

[0066] (9) Close the pore water pressure valve, unload at the same strain rate as when loading, and record the change in vertical stress.

[0067] (10) After unloading is completed, turn off the universal testing machine, disassemble the specimen, and the test ends.

[0068] Under the condition of setting an appropriate strain rate, based on the one-dimensional linear theory of CRS, the vertical effective stress σ' in the specimen can be calculated by the following formula:

[0069]

[0070] In the formula, σ is the measured total vertical stress, σ' is the effective stress, and μ b is the measured pore water pressure at the bottom;

[0071] The calculation of the void ratio is as follows:

[0072]

[0073] In the formula: e i is the void ratio under a certain level of pressure, ∑h i is the total deformation of the height of the specimen at a certain moment, and h0 is the initial height of the specimen.

[0074] The calculation of the axial strain is as follows:

[0075]

[0076] The coefficient of consolidation can be calculated by the following formula:

[0077]

[0078] Wherein, Δσ' is the increment of the vertical effective stress within the time Δt, and are respectively the average specimen height and the average excess pore water pressure at the bottom of the specimen within the time Δt.

[0079] The coefficient of permeability is calculated by the following formula;

[0080]

[0081] Wherein, γ w is the unit weight of water, r is the test strain rate, H is the specimen height, and μ b,n is the pore water pressure at the bottom of the specimen measured at a certain moment.

[0082] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions described in the foregoing embodiments, or perform equivalent replacements for some of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A continuous loading consolidation test device for large-scale model specimens used in the study of earth heritage construction techniques, characterized in that Comprising: A universal testing machine, a consolidation container, a water head saturation device, and a pore water pressure measurement system; The consolidation container is placed on the universal testing machine, and a large-scale structural specimen is placed inside; The universal testing machine is used to apply a vertical load at a constant rate to the large-scale structural specimen and automatically record the vertical displacement, vertical stress, and time; The water head saturation device is connected to the inside of the consolidation container and is used to introduce distilled water into the consolidation container to saturate the large-scale structural specimen with water head; The pore water pressure measurement system records the change in the pore water pressure at the bottom of the specimen during the consolidation process and calculates and analyzes the test data based on the CRS one-dimensional linear consolidation theory.

2. The continuous loading consolidation test device for large-scale model specimens used in the research on the construction technology of earthen ruins according to claim 1, characterized in that, The universal testing machine adopts a floor-standing double-column machine, including a base and an upper functional head. The upper functional head is installed on the base, and there is enough space between the base and the upper functional head to stably place the consolidation container.

3. The continuous loading consolidation test device for large-size model specimens used in the research on the construction technology of earthen ruins according to claim 1 or 2, characterized in that, The consolidation container is a steel rectangular box with an open top, a sealed bottom, and an inlet valve and a pore water pressure sensor connection port are provided. A permeable stone slab is provided at the bottom end inside the consolidation container, and a filter paper is provided between the permeable stone slab and the lower surface of the large-scale structural specimen.

4. A large-scale model specimen continuous loading consolidation test device for earthen heritage site construction technology research according to claim 3, characterized in that, It further includes a pressure cover. The pressure cover is a double-layer metal plate structure. The total area of the lower metal plate is the same as the bottom area of the consolidation container. The upper metal plate and the lower metal plate are welded distributively by steel bars; a drainage channel is provided inside the middle axis position of the upper metal plate and the lower metal plate, and a drainage valve is provided on the side wall of the upper metal plate.

5. The large-scale model specimen continuous loading consolidation test device for the study of the construction technology of earthen ruins according to claim 4, characterized in that, A groove is provided at the bottom of the lower metal plate for nesting and placing the permeable stone slab. A filter paper is provided between the permeable stone slab and the upper surface of the large-scale structural specimen, and a sealing rubber ring is provided at the edge of the groove.

6. The large-size model specimen continuous loading consolidation test device for the study of the construction technology of earthen ruins according to claim 3, characterized in that, The water head saturation device includes a distilled water bucket and a water guide pipe. The distilled water bucket is connected to the inlet valve through the water guide pipe.

7. A large-size model specimen continuous loading consolidation test device for earthen site construction technology research according to claim 3, characterized in that, The pore water pressure acquisition device includes a pore water pressure sensor, a data acquisition system, and a computer; the pore water pressure sensor is installed at the position of the pore water pressure sensor connection port, and the pore water pressure sensor is communicatively connected to the computer through the data acquisition system.

8. A large-size model specimen continuous loading consolidation test device for the study of earth site construction technology according to claim 1, characterized in that, The continuous loading consolidation test of the large-scale structural specimen is divided into a constant strain rate loading stage, a constant stress stage, and a rebound stage.

9. A continuous loading consolidation test method for large-size model specimens used in the research of earthen heritage construction techniques, characterized in that, It includes the following steps: Step S1: Place the consolidation container on the universal testing machine, apply vaseline to the inner side wall of the consolidation container, place a permeable stone slab at the bottom of the consolidation container, add distilled water, open the inlet valve, remove the air at the bottom of the consolidation container, close the inlet valve after the exhaust is completed, soak the permeable stone slab with distilled water, and place a filter paper on the permeable stone slab; Step S2: Put the prepared large-scale structural specimen into the consolidation container, or directly prepare the large-scale structural specimen in the consolidation container, place a filter paper on the large-scale structural specimen, place a rubber ring at the edge of the large-scale structural specimen, nest the pressure cover plate with the permeable stone slab, and place it on the large-scale structural specimen; Step S3: Operate the universal testing machine to apply a vertical pressure of 1 kPa to the specimen, level the large-scale structural specimen, and make the pressure cover plate sealed with the large-scale structural specimen; Step S4: Connect the water inlet valve at the bottom of the consolidation container to the water conduction pipe. The water conduction pipe is connected to the distilled water bucket to provide a water head height of 1 m to saturate the specimen with the water head and simultaneously saturate the pore water pressure sensor probe with high-quality degassed water. After water starts flowing out of the drainage valve of the pressure application cover plate and stabilizes, the specimen saturation is completed, the water inlet valve of the consolidation container is closed, and the bottom of the consolidation container is connected to the pore water pressure sensor; Step S5: According to the experimental requirements, set the loading program of the universal testing machine: The first stage is the constant strain rate loading stage, continuously load until the expected stress or strain, and unidirectional drainage at the top of the large-scale structured specimen; The second stage is the constant load stage, in which the pore water pressure dissipates under the condition of constant vertical deformation; The third stage is the unloading stage, and the large-scale structured specimen is unloaded under the condition of the strain rate equal to that during loading; The universal testing machine can record the vertical stress, strain, time, and pore water pressure.

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