Cylindrical foundation penetration test model box

Abstract

The utility model discloses a cylindrical foundation penetration test model box which comprises a model box main body, a permeable layer structure and a pore water pressure gauge, and the model box main body comprises a first water passing valve, a model box frame, toughened glass and a second water passing valve; model box plates are fixed to the bottom, the left side wall and the right side wall of the model box frame, and tempered glass is fixed to the front side wall and the rear side wall. The first water passing valves are arranged on the two sides, close to the bottom, of the model box body, and the second water passing valves are arranged on the two sides, close to the top, of the model box body; the permeable layer structure comprises a water filtering plate, a first non-woven geotextile, a geogrid and a second non-woven geotextile which are sequentially arranged from bottom to top; and the pore water pressure gauge is mounted in the model box main body through the pore water pressure gauge mounting structure. According to the utility model, the water filtering plate and the non-woven geotechnical cloth are laid, so that the water-permeable and sand-impermeable performance is good, and drainage consolidation and soil saturation can be effectively carried out; geogrids are laid, so that the bearing capacity of the foundation is effectively improved, and the stability of the foundation is enhanced.

Description

Technical Field

[0001] The utility model relates to the technical field of model boxes, in particular to a barrel foundation penetration test model box. Background Art

[0002] In recent years, barrel foundations have been widely used in the field of marine engineering due to their dual advantages of high construction efficiency and cost-effectiveness. These foundation types, such as offshore negative pressure sinking foundations, suction barrel foundations, and suction caisson foundations, are initially driven by their own weight to a specified depth, and then use negative pressure technology to achieve deeper sinking operations. At this time, if the negative pressure is too large and exceeds the bearing capacity of the soil, it may induce complex geological problems such as seepage and soil liquefaction, posing a threat to engineering safety. However, in actual engineering, the measurement of excess pore water pressure in soil faces many problems. Therefore, it is necessary to design a test model box that can simulate the marine lake environment. By monitoring the water and soil pressure inside, the changing law of excess pore water pressure in the soil during the barrel foundation sinking operation can be analyzed and summarized.

[0003] The existing cylindrical foundation test model box currently has the following problems: 1. The bottom of the model box is directly filled with soil. During the soil saturation process, the water valve at the bottom is in direct contact with the soil, which can easily cause the water valve to be blocked; 2. The wires of the existing model box equipped with pore water pressure gauges are all led upward from the fixed rod. During the cylindrical foundation negative pressure penetration test, they cannot pass through the cylindrical foundation to the outside world, so they can only be connected to the outside world from the bottom of the cylindrical foundation, which seriously affects the results of the negative pressure penetration test.

[0004] Therefore, it is urgent to improve the existing model box and design a model box that is convenient for conducting the barrel foundation negative pressure penetration simulation test. Utility Model Content

[0005] (1) Technical issues to be resolved

[0006] The technical problem to be solved by the utility model is to provide a cylindrical foundation sinking test model box, which improves the shortcomings of the existing model box by laying a water filter plate, a non-woven geotextile and a geogrid; the water filter plate and the non-woven geotextile both have good water-permeable and sand-impermeable properties, and can effectively carry out drainage consolidation and soil saturation; at the same time, laying the geogrid can effectively improve the bearing capacity of the foundation and enhance the stability of the foundation.

[0007] (2) Technical solution

[0008] The solution adopted by the utility model to solve the above technical problems is a cylindrical foundation penetration test model box, which includes a model box body, a permeable layer structure and a pore water pressure gauge.

[0009] The model box body includes a first water valve, a model box frame, tempered glass, and a second water valve; the bottom and left and right side walls of the model box frame are fixed with model box panels, and the front and rear side walls are fixed with tempered glass; the first water valve is provided on both sides of the model box body near its bottom, and the second water valve is provided on both sides of the model box body near its top;

[0010] The permeable layer structure includes a water filter plate, a first non-woven geotextile, a geogrid, and a second non-woven geotextile, which are arranged in sequence from bottom to top; the water filter plate is arranged at the bottom of the model box body, and the top of the water filter plate is lower than the bottom of the first water valve; the bottom of the first non-woven geotextile is lower than the bottom of the first water valve, and the top is higher than the top of the first water valve; the geogrid is placed between the first non-woven geotextile and the second non-woven geotextile, and the bottom of the geogrid is higher than the top of the first water valve;

[0011] The pore water pressure gauge is installed in the model box body through a pore water pressure gauge installation structure.

[0012] Specifically, the two first water valves are at the same height from the bottom of the model box body; and the two second water valves are at the same height from the top of the model box body.

[0013] In some embodiments, the pore water pressure gauge mounting structure includes a support rod; the top of the support rod is level with the top of the soil layer, and the bottom is pancake-shaped and close to the bottom of the model box body; the pore water pressure gauge is tied to the support rod; and, the support rod is provided with a plurality of pore water pressure gauges spaced from bottom to top, and one of the pore water pressure gauges is tied to the support rod near the top of the soil layer.

[0014] Specifically, the support rod is made of stainless steel.

[0015] In some embodiments, the support rod is provided with five installation positions from bottom to top, and each installation position is bundled with two pore water pressure gauges arranged left and right.

[0016] In some embodiments, the conductive wires of the pore water pressure gauges connect each pore water pressure gauge together, are arranged along the surface of the second non-woven geotextile of the permeable layer structure and extend to the side wall of the model box body, and are led upward along the side wall of the model box body to the outside of the model box body.

[0017] In some embodiments, the pore water pressure gauge installation structure further includes a bottom limiting sleeve, a limiting adapter, a protective sleeve and a limiting component;

[0018] The bottom limiting sleeve is arranged in the permeable layer structure, with its bottom lower than the top of the water filter plate and its top higher than the bottom of the geogrid; and the bottom limiting sleeve is sleeved outside the support rod, and non-woven geotextile is filled between the bottom limiting sleeve and the support rod, so that the installation between the support rod and the bottom limiting sleeve is tighter and more stable;

[0019] The limit adapter is sleeved outside the bottom limit sleeve, with its bottom placed on the top of the water filter plate and its top flush with the top of the second non-woven geotextile; and the lower half of the limit adapter is tightly attached to the outside of the bottom limit sleeve, and the upper half is spaced apart from the support rod;

[0020] The protective sleeve is sleeved on the outside of the support rod, with its bottom inserted into the upper half of the limit adapter and its top extending out of the top of the model box body;

[0021] The limiting component is installed on the top of the support rod and abuts against the inner wall of the protective sleeve.

[0022] Specifically, the non-woven geotextile is made of polypropylene; the bottom limiting sleeve, limiting adapter, protective sleeve and limiting component are all made of polyvinyl chloride.

[0023] In some embodiments, the upper half of the limit adapter includes a cylindrical upper port and a bent portion bent from the bottom of the upper port and connected to the lower half of the limit adapter; the protective sleeve is placed in the upper port, and the inner diameter of the upper port is equal to the outer diameter of the protective sleeve; the outer diameter of the limit component is equal to the inner diameter of the protective sleeve.

[0024] By adopting the above solution, it can be ensured that the protective sleeve is stably installed above the limit adapter, preventing the protective sleeve from hitting the pore water pressure gauge and affecting the test data.

[0025] In some embodiments, an opening is provided at the junction of the protective sleeve and the top of the limit adapter for leading out a wire of the pore water pressure gauge.

[0026] In some embodiments, the support rod includes a first support rod, a second support rod and a third support rod arranged at intervals; and, the first support rod is arranged at the geometric center of the bottom of the model box body, the second support rod and the third support rod are respectively arranged on both sides of the first support rod, and the projections of the first support rod, the second support rod and the third support rod on the bottom of the model box body are located on the same straight line.

[0027] In some embodiments, the distance from the third support rod to the first support rod is twice the distance from the second support rod to the first support rod.

[0028] The above scheme is adopted to set up three support rods, which can be applied to the exploration tests of different penetration problems.

[0029] In some embodiments, the first non-woven geotextile is arranged between the water filter plate and the geogrid, and the second non-woven geotextile is arranged on the top of the geogrid; and multiple layers of the first non-woven geotextile are arranged between the water filter plate and the geogrid; a layer of the second non-woven geotextile is arranged on the top of the geogrid; and the first non-woven geotextile and the second non-woven geotextile are connected on one side close to the support rod to separate the geogrid and the support rod.

[0030] In some embodiments, the model box frame and the model box plate are made of stainless steel; the water filter plate and the geogrid are made of high-density polyethylene; and the first non-woven geotextile and the second non-woven geotextile are made of polypropylene.

[0031] By adopting the above scheme, the water filter plate, the first non-woven geotextile and the second non-woven geotextile all have good water-permeable and sand-impermeable properties, and can effectively carry out drainage consolidation and soil saturation; at the same time, laying geogrids can effectively improve the bearing capacity of the foundation and enhance the stability of the foundation.

[0032] After the construction of the barrel foundation penetration test model box of the utility model is completed, it is necessary to fill the soil, drain and consolidate it, and then remove the protective casing. The specific steps are as follows:

[0033] Step 1: After filling water to the design elevation, use the falling sand method to fill the soil until the filling height is higher than the top of the limit component. During the filling process, the first water valve needs to be opened to drain water, and the water level should be controlled not lower than the design elevation and not higher than the height of the model box;

[0034] Step 2: inject water through the second water valve and drain water through the first water valve to drain and consolidate the soil;

[0035] Step 3: Slowly pull out the protective casing vertically upward. Each time the bottom of the protective casing passes the top of the pore water pressure gauge, it needs to remain still for a while until the pore water pressure gauge reading stabilizes before pulling it out to the next node. After removing the protective casing, according to the test design requirements, inject water to 1-2 cm above the soil layer; when the protective casing is removed 3-4 cm, the soil remains saturated and does not affect the measurement of pore water pressure.

[0036] (3) Beneficial effects

[0037] Compared with the existing technology, the utility model designs a cylindrical foundation penetration test model box.

[0038] (1) The present invention improves the shortcomings of the existing model box by laying a water filter plate, a first non-woven geotextile, a geogrid and a second non-woven geotextile at the bottom of the model box body; the water filter plate, the first non-woven geotextile and the second non-woven geotextile all have good water permeability but sand impermeability, and can effectively carry out drainage consolidation and soil saturation; at the same time, laying the geogrid can effectively improve the bearing capacity of the foundation and enhance the stability of the foundation;

[0039] (2) The utility model is provided with inlet / outlet ports at the top and bottom of the model box body. The first water valve at the bottom can be used for bottom water injection and drainage consolidation; the second water valve at the top can be used for injecting water into the soil surface to simulate the actual marine environment. The design of two water valves greatly improves the efficiency of the test.

[0040] (3) The utility model is provided with a pore water pressure gauge on the support rod. The wire of the pore water pressure gauge in the traditional model box is led out from the bottom to the top along the support rod, which will cause the wire to be pressed during the sinking of the barrel foundation, affecting the final test data. Therefore, a wiring method is designed for this test model box, which extends the wire from the top of the support rod downward to the surface of the second non-woven geotextile and leads it out from the two side walls of the model box body, effectively avoiding the interference caused by the wire when the barrel foundation is sunk.

[0041] (4) The present invention is provided with three support rods, wherein the first and second support rods are main test rods, and the third support rod is a spare rod, which can be applied to the exploration test of different penetration problems;

[0042] (5) The utility model is provided with a bottom limit sleeve and a limit adapter at the bottom of the model box body, and a limit component at the top, which ensures that the protective sleeve avoids touching the pore water pressure gauge during installation and removal, and avoids the impact of operating errors that touch the pore water pressure gauge on the test. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the following briefly introduces the drawings required for use in the embodiments. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0044] Figure 1 This is a schematic diagram of a cylindrical foundation penetration test model box of the present utility model;

[0045] Figure 2This is a schematic diagram of a cylindrical foundation penetration test model box of the present invention during a penetration test;

[0046] Figure 3 This is a cross-sectional schematic diagram of a cylindrical foundation penetration test model box according to the present invention from another perspective;

[0047] Figure 4 for Figure 3 A in the middle is an enlarged schematic diagram;

[0048] Figure 5 for Figure 2 Cross-section at AA;

[0049] Figure 6 This is a cross-sectional view of the bottom permeable layer structure of a cylindrical foundation penetration test model box of the present utility model;

[0050] Figure 7 Another cross-sectional schematic diagram of a cylindrical foundation penetration test model box of the utility model;

[0051] Figure 8 for Figure 2 Cross-section at the middle BB;

[0052] Figure 9 This is a schematic diagram from another angle of a cylindrical foundation penetration test model box of the utility model during the penetration test process.

[0053] The names of the components corresponding to the various figure marks in the figure are: 1. Model box body; 1-1. First water valve; 1-2. Model box frame; 1-3. Tempered glass; 1-4. Second water valve; 2. Bottom permeable layer structure; 2-1. Water filter plate; 2-2. First non-woven geotextile; 2-3. Geogrid; 2-4. Second non-woven geotextile; 3. Pore water pressure gauge installation structure; 3-1. Support rod; 3-1-1. First support rod; 3-1-2. Second support rod; 3-1-3. Third support rod; 3-2. Bottom limit sleeve; 3-3. Limit adapter; 3-3-1. Upper port; 3-3-2. Bending part; 3-4. Protective sleeve; 3-5. Limit component; 4. Pore water pressure gauge; 4-1. Wire; 5. Cylindrical foundation; 3-6. Non-woven geotextile. DETAILED DESCRIPTION

[0054] The following embodiments are used to illustrate the present invention, but are not intended to limit the scope of the present invention.

[0055] In the description of this utility model, it should be noted that, unless otherwise expressly specified or limited, the terms "mounted," "connected," and "connected" should be understood in a broad sense. For example, they can refer to fixed connections, detachable connections, or integral connections; mechanical connections or electrical connections; direct connections or indirect connections through an intermediate medium; and internal communication between two components. Those skilled in the art will understand the specific meanings of the above terms in the present invention based on the specific circumstances.

[0056] The following describes the embodiments of the present application through specific examples, and those skilled in the art can easily understand other advantages and effects of the present application from the contents disclosed in this specification. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. The present application can also be implemented or applied through other different specific embodiments, and the details in this specification can also be modified or changed in various ways based on different viewpoints and applications without departing from the spirit of the present application. It should be noted that, in the absence of conflict, the features in the following embodiments and embodiments can be combined with each other. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without making creative work are within the scope of protection of this application.

[0057] It should be noted that various aspects of the embodiments within the scope of the appended claims are described below. It should be apparent that the aspects described herein can be embodied in a wide variety of forms, and any specific structure and / or function described herein is merely illustrative. Based on this application, it should be understood by those skilled in the art that an aspect described herein can be implemented independently of any other aspect, and two or more of these aspects can be combined in various ways. For example, any number and aspect described herein can be used to implement the device and / or practice the method. In addition, other structures and / or functionalities other than one or more of the aspects described herein can be used to implement this device and / or practice this method.

[0058] It should also be noted that the illustrations provided in the following embodiments are only schematic illustrations of the basic concept of the present application. The illustrations only show components related to the present application and are not drawn according to the number, shape and size of components in actual implementation. In actual implementation, the type, quantity and proportion of each component can be changed at will, and the component layout type may also be more complicated.

[0059] Additionally, in the following description, specific details are provided to provide a thorough understanding of the examples, however, one skilled in the art will appreciate that the examples can be practiced without these specific details.

[0060] The following describes the technical solutions provided by various embodiments of the present application in conjunction with the accompanying drawings.

[0061] like Figures 1-9 As shown, the utility model provides a cylindrical foundation penetration test model box, including a model box body 1, a permeable layer structure 2 and a pore water pressure gauge 4, the model box body 1 includes a first water valve 1-1, a model box frame 1-2, a tempered glass 1-3 and a second water valve 1-4; the bottom and left and right side walls of the model box frame 1-2 are fixed with model box panels, and the front and back side walls are fixed with tempered glass 1-3; the first water valve 1-1 is arranged on both sides of the model box body 1 near its bottom, and the second water valve 1-4 is arranged on both sides of the model box body 1 near its top; the permeable layer structure 2 includes a water filter plate 2-1, a first non-woven soil filter plate 2-3, a second non-woven soil filter plate 2-4, a first non-woven soil filter plate 2-5, a first non-woven soil filter plate 2-6, a first non-woven soil filter plate 2-7, a first non-woven soil filter plate 2-8, a first non-woven soil filter plate 2-9, a first non-woven soil filter plate 2-1 ...2, a first non-woven soil filter plate 2-3, a first non-woven soil filter plate 2-4, a first non-woven soil filter plate 2-1, a first non-woven soil filter plate 2-1, a first non-woven soil filter plate 2-3, a first non-woven soil filter plate 2-4, a first non-woven soil filter plate 2-1, a first non-woven soil filter plate 2- Geotextile 2-2, geogrid 2-3 and second non-woven geotextile 2-4; the water filter plate 2-1 is arranged at the bottom of the model box body 1, and the top of the water filter plate 2-1 is lower than the bottom of the first water valve 1-1; the bottom of the first non-woven geotextile 2-2 is lower than the bottom of the first water valve 1-1, and the top is higher than the top of the first water valve 1-1; the geogrid 2-3 is placed between the first non-woven geotextile 2-2 and the second non-woven geotextile 2-4, and the bottom of the geogrid 2-3 is higher than the top of the first water valve 1-1; the pore water pressure gauge 4 is installed in the model box body 1 through the pore water pressure gauge 4 installation structure. Specifically, the two first water valves 1-1 are at the same height from the bottom of the model box body 1; the two second water valves 1-4 are at the same height from the top of the model box body 1. By adopting the above scheme, the shortcomings of the existing model box are improved by laying a water filter plate 2-1, a first non-woven geotextile 2-2, a geogrid 2-3 and a second non-woven geotextile 2-4 at the bottom of the model box body 1; the water filter plate 2-1, the first non-woven geotextile 2-2 and the second non-woven geotextile 2-4 all have good water-permeable and sand-impermeable properties, and can effectively carry out drainage, consolidation and soil saturation; at the same time, laying the geogrid 2-3 can effectively improve the bearing capacity of the foundation and enhance the stability of the foundation; and inlet / outlet ports are provided at the top and bottom of the model box body 1, and the first water valve 1-1 at the bottom can be used for bottom water injection and drainage consolidation; the second water valve 1-4 at the top can be used to inject water into the soil surface to simulate the actual marine environment; the design of the two water valves greatly improves the efficiency of the test.

[0062] In some embodiments, the mounting structure for the pore-water pressure gauge 4 includes a support rod 3-1; the top of the support rod 3-1 is flush with the top of the soil layer, and the bottom is round and in a pancake shape, resting against the bottom of the model box body 1. The pore-water pressure gauge 4 is strapped to the support rod 3-1. Furthermore, multiple pore-water pressure gauges 4 are spaced apart from each other on the support rod 3-1, with one pore-water pressure gauge 4 strapped to the support rod 3-1 near the top of the soil layer. Specifically, the support rod 3-1 is made of stainless steel. In some embodiments, the support rod 3-1 has five mounting locations, with two pore-water pressure gauges 4 strapped to each location. In some embodiments, the wires 4-1 of the pore-water pressure gauges 4 connect each pore-water pressure gauge 4 and are arranged along the surface of the second non-woven geotextile 2-4 of the aquifer structure 2, extending to the sidewall of the model box body 1 and then extending upward along the sidewall of the model box body 1 to the outside of the model box body 1. With the above-mentioned solution, a pore water pressure gauge 4 is provided on the support rod 3-1. The wire 4-1 of the pore water pressure gauge 4 in the traditional model box is led out from bottom to top along the support rod 3-1, which will cause the barrel foundation to press on the wire 4-1 during the downward sinking process, affecting the final data of the test; therefore, this test model box is designed with a wiring method, extending the wire 4-1 from the top of the support rod 3-1 downward to the surface of the second non-woven geotextile 2-4, and leading it out from the two side walls of the model box body 1, effectively avoiding the interference caused by the wire 4-1 when the barrel foundation 5 is sunk.

[0063] In some embodiments, the pore water pressure gauge 4 installation structure further includes a bottom limiting sleeve 3-2, a limiting adapter 3-3, a protective sleeve 3-4 and a limiting component 3-5; the bottom limiting sleeve 3-2 is arranged in the permeable layer structure 2, and its bottom is lower than the top of the water filter plate 2-1, and its top is higher than the bottom of the geogrid 2-3; and the bottom limiting sleeve 3-2 is sleeved outside the support rod 3-1, and a non-woven geotextile 6 is filled between the bottom limiting sleeve 3-2 and the support rod 3-1, so that the installation between the support rod 3-1 and the bottom limiting sleeve 3-2 is tighter and more stable; the limiting adapter 3 -3 is sleeved outside the bottom limiting sleeve 3-2, and its bottom is placed on the top of the water filter plate 2-1, and its top is flush with the top of the second non-woven geotextile 2-4; and the lower half of the limiting adapter 3-3 is tightly attached to the outside of the bottom limiting sleeve 3-2, and the upper half is spaced apart from the support rod 3-1; the protective sleeve 3-4 is sleeved outside the support rod 3-1, and its bottom is inserted into the upper half of the limiting adapter 3-3, and the top extends out of the top of the model box body 1; the limiting component 3-5 is installed on the top of the support rod 3-1 and abuts against the inner wall of the protective sleeve 3-4. Specifically, the non-woven geotextile is made of polypropylene; the bottom limiting sleeve 3-2, the limiting adapter 3-3, the protective sleeve 3-4 and the limiting component 3-5 are all made of polyvinyl chloride.

[0064] In some embodiments, the upper half of the limit adapter 3-3 includes a cylindrical upper port 3-3-1, and a bent portion 3-3-2 bent from the bottom of the upper port 3-3-1 and connected to the lower half of the limit adapter 3-3; the protective sleeve 3-4 is placed in the upper port 3-3-1, and the inner diameter of the upper port 3-3-1 is equal to the outer diameter of the protective sleeve 3-4; the outer diameter of the limit component 3-5 is equal to the inner diameter of the protective sleeve 3-4; it can ensure that the protective sleeve 3-4 is stably installed above the limit adapter 3-3, preventing the protective sleeve 3-4 from hitting the pore water pressure gauge 4 and affecting the test data. With this solution, a bottom limiting sleeve 3-2 and a limiting adapter 3-3 are provided at the bottom of the model box body 1, and a limiting component 3-5 is provided at the top. This ensures that the protective sleeve 3-4 avoids contact with the pore water pressure gauge 4 during installation and removal, thus preventing the impact of the pore water pressure gauge 4 on the test due to operational errors. In some embodiments, an opening is provided at the junction of the protective sleeve 3-4 and the top of the limiting adapter 3-3 for leading out the wire 4-1 of the pore water pressure gauge 4.

[0065] In some embodiments, the support rods 3-1 include a first support rod 3-1-1, a second support rod 3-1-2, and a third support rod 3-1-3 arranged at intervals; the first support rod 3-1-1 is arranged at the geometric center of the bottom of the model box body 1, the second support rod 3-1-2 and the third support rod 3-1-3 are arranged on either side of the first support rod 3-1-1, and the projections of the first support rod 3-1-1, the second support rod 3-1-2, and the third support rod 3-1-3 on the bottom of the model box body 1 are located on the same straight line. In some embodiments, the distance L1 from the third support rod 3-1-3 to the first support rod 3-1-1 is twice the distance L2 from the second support rod 3-1-2 to the first support rod 3-1-1. Using the above solution, three support rods 3-1 are set up, wherein the first support rod 3-1-1 and the second support rod 3-1-2 are the main test rods, and the third support rod 3-1-3 is a spare rod, which can be used for exploratory tests of different penetration problems.

[0066] In some embodiments, the first non-woven geotextile 2-2 is arranged between the water filter plate 2-1 and the geogrid 2-3, and the second non-woven geotextile 2-4 is arranged on top of the geogrid 2-3; and multiple layers of the first non-woven geotextile 2-2 are arranged between the water filter plate 2-1 and the geogrid 2-3; a layer of the second non-woven geotextile 2-4 is arranged on top of the geogrid 2-3; and the first non-woven geotextile 2-2 and the second non-woven geotextile 2-4 are connected near the side of the limit adapter 3-3 to separate the geogrid 2-3 and the limit adapter 3-3. In some embodiments, the model box frame 1-2 and the model box plate are made of stainless steel; the water filter plate 2-1 and the geogrid 2-3 are made of high-density polyethylene; and the first non-woven geotextile 2-2 and the second non-woven geotextile 2-4 are made of polypropylene. By adopting the above scheme, the water filter plate 2-1, the first non-woven geotextile 2-2 and the second non-woven geotextile 2-4 all have good water-permeable and sand-impermeable properties, and can effectively carry out drainage consolidation and soil saturation; at the same time, laying the geogrid 2-3 can effectively improve the bearing capacity of the foundation and enhance the stability of the foundation.

[0067] After the construction of the barrel foundation penetration test model box of the utility model is completed, it is necessary to fill the soil, drain and consolidate it, and pull out the protective sleeve 3-4. The specific steps are as follows:

[0068] Step 1: After filling water to the design elevation, use the falling sand method to fill the soil until the filling height is higher than the top of the limiting component 3-5. During the filling process, the first water valve 1-1 needs to be opened to drain water, and the water level should be controlled not lower than the design elevation and not higher than the height of the model box;

[0069] Step 2: inject water through the second water valve 1-4 and drain water through the first water valve 1-1 to drain and consolidate the soil;

[0070] Step 3: Slowly pull out the protective sleeve 3-4 vertically upward. Each time the bottom of the protective sleeve 3-4 passes the top of the point of the pore water pressure gauge 4, it needs to stay still for a while until the reading of the pore water pressure gauge 4 stabilizes before pulling it out to the next node. After removing the protective sleeve 3-4, according to the test design requirements, water is injected to 1-2 cm above the soil layer; so that when the protective sleeve 3-43-4 cm is removed, the soil remains saturated and does not affect the measurement of the pore water pressure.

[0071] The same or similar parts between the various embodiments in this specification can be referred to each other, and each embodiment focuses on the differences from other embodiments.

[0072] The above description is merely a specific embodiment of the present application, but the scope of protection of the present application is not limited thereto. Any changes or substitutions that can be easily conceived by a person skilled in the art within the technical scope disclosed in the present application should be included in the scope of protection of the present application. Therefore, the scope of protection of the present application should be based on the scope of protection of the claims.

Claims

1. A cylindrical foundation penetration test model box, characterized by: It includes a model box body (1), a permeable layer structure (2) and a pore water pressure gauge (4), The model box body (1) comprises a first water valve (1-1), a model box frame (1-2), tempered glass (1-3) and a second water valve (1-4); the bottom and left and right side walls of the model box frame (1-2) are fixed with model box panels, and the front and rear side walls are fixed with tempered glass (1-3); the first water valve (1-1) is arranged on both sides of the model box body (1) near the bottom thereof, and the second water valve (1-4) is arranged on both sides of the model box body (1) near the top thereof; The permeable layer structure (2) comprises a water filter plate (2-1), a first non-woven geotextile (2-2), a geogrid (2-3) and a second non-woven geotextile (2-4) arranged in sequence from bottom to top; the water filter plate (2-1) is arranged at the bottom of the model box body (1), and the top of the water filter plate (2-1) is lower than the bottom of the first water valve (1-1); the bottom of the first non-woven geotextile (2-2) is lower than the bottom of the first water valve (1-1), and the top is higher than the top of the first water valve (1-1); The pore water pressure gauge (4) is installed in the model box body (1) via a pore water pressure gauge (4) installation structure.

2. The barrel foundation penetration test model box according to claim 1, characterized in that: The pore water pressure gauge (4) installation structure comprises a support rod (3-1); the top of the support rod (3-1) is flush with the top of the soil layer, and the bottom is in close contact with the bottom of the model box body (1); the pore water pressure gauge (4) is tied to the support rod (3-1); and a plurality of the pore water pressure gauges (4) are arranged at intervals from bottom to top on the support rod (3-1), and one of the pore water pressure gauges (4) is tied to the support rod (3-1) near the top of the soil layer.

3. The barrel foundation penetration test model box according to claim 2, characterized in that: The conducting wires (4-1) of the pore water pressure gauges (4) connect each pore water pressure gauge (4) together, are arranged along the surface of the second non-woven geotextile (2-4) of the permeable layer structure (2), extend to the side wall of the model box body (1), and are led upward along the side wall of the model box body (1) to the outside of the model box body (1).

4. The barrel foundation penetration test model box according to claim 2, characterized in that: The pore water pressure gauge (4) installation structure further comprises a bottom limiting sleeve (3-2), a limiting adapter (3-3), a protective sleeve (3-4) and a limiting component (3-5); The bottom limiting sleeve (3-2) is arranged in the permeable layer structure (2), and its bottom is lower than the top of the water filter plate (2-1), and its top is higher than the bottom of the geogrid (2-3); and the bottom limiting sleeve (3-2) is sleeved outside the support rod (3-1), and a non-woven geotextile (6) is filled between the bottom limiting sleeve (3-2) and the support rod (3-1); The limit adapter (3-3) is sleeved outside the bottom limit sleeve (3-2), and its bottom is placed on the top of the water filter plate (2-1), and its top is flush with the top of the second non-woven geotextile (2-4); and the lower half of the limit adapter (3-3) is tightly attached to the outside of the bottom limit sleeve (3-2), and the upper half is spaced apart from the support rod (3-1); The protective sleeve (3-4) is sleeved on the outside of the support rod (3-1), with its bottom inserted into the upper half of the limit adapter (3-3) and its top extending out of the top of the model box body (1); The limiting component (3-5) is installed on the top of the support rod (3-1) and abuts against the inner wall of the protective sleeve (3-4).

5. The barrel foundation penetration test model box according to claim 4, characterized in that: The upper half of the position-limiting adapter (3-3) comprises a cylindrical upper port (3-3-1) and a bent portion (3-3-2) bent from the bottom of the upper port (3-3-1) and connected to the lower half of the position-limiting adapter (3-3); the protective sleeve (3-4) is placed in the upper port (3-3-1), and the inner diameter of the upper port (3-3-1) is equal to the outer diameter of the protective sleeve (3-4); and the outer diameter of the position-limiting component (3-5) is equal to the inner diameter of the protective sleeve (3-4).

6. The barrel foundation penetration test model box according to claim 4, characterized in that: An opening is provided at the junction of the protective sleeve (3-4) and the top of the limit adapter (3-3) for leading out a wire (4-1) of the pore water pressure gauge (4).

7. The barrel foundation penetration test model box according to claim 2, characterized in that: The support rod (3-1) comprises a first support rod (3-1-1), a second support rod (3-1-2) and a third support rod (3-1-3) arranged at intervals; the first support rod (3-1-1) is arranged at the geometric center of the bottom of the model box body (1), the second support rod (3-1-2) and the third support rod (3-1-3) are arranged on both sides of the first support rod (3-1-1), respectively, and the projections of the first support rod (3-1-1), the second support rod (3-1-2) and the third support rod (3-1-3) on the bottom of the model box body (1) are located on the same straight line.

8. The barrel foundation penetration test model box according to claim 7, characterized in that: The distance between the third support rod (3-1-3) and the first support rod (3-1-1) is twice the distance between the second support rod (3-1-2) and the first support rod (3-1-1).

9. The barrel foundation penetration test model box according to claim 2, characterized in that: The first non-woven geotextile (2-2) is arranged between the water filter plate (2-1) and the geogrid (2-3), and the second non-woven geotextile (2-4) is arranged on top of the geogrid (2-3); multiple layers of the first non-woven geotextile (2-2) are arranged between the water filter plate (2-1) and the geogrid (2-3); a layer of the second non-woven geotextile (2-4) is arranged on top of the geogrid (2-3); and the first non-woven geotextile (2-2) and the second non-woven geotextile (2-4) are connected near one side of the support rod (3-1) to separate the geogrid (2-3) and the support rod (3-1).

10. The barrel foundation penetration test model box according to claim 1, characterized in that: The model box frame (1-2) and the model box plate are made of stainless steel; the water filter plate (2-1) and the geogrid (2-3) are made of high-density polyethylene; and the first non-woven geotextile (2-2) and the second non-woven geotextile (2-4) are made of polypropylene.

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