Grouting belt method in-situ testing device based on soil pressure cell

Abstract

The utility model discloses a grouting belt method in-situ testing device based on an earth pressure cell, which comprises a reinforcement cage, a mounting frame is fixedly arranged on the reinforcement cage, the earth pressure cell is arranged in the mounting frame in a sliding manner, a directional limiting device is fixedly arranged between the mounting frame and the earth pressure cell, and the directional limiting device is fixedly connected with the reinforcement cage. The sliding direction of the soil pressure box is the radial direction of the reinforcement cage, and a grouting belt is further arranged between the soil pressure box and the mounting frame; after the grouting belt is filled with grouting materials, the grouting belt is continuously expanded to push the soil pressure box to advance towards the hole wall, finally the soil pressure box is tightly contacted with the soil body of the hole wall, the soil pressure box is protected from being wrapped by concrete, the soil pressure box is ensured to be effective, the soil pressure box is clamped between the cast-in-place pile and the surrounding soil body, the three are tightly contacted, and the transmission path of soil pressure is ensured.

Description

Technical Field

[0001] This application relates to the field of civil engineering technology, and more specifically, to an in-situ testing device based on the grouting band method using an earth pressure cell. Background Technology

[0002] Reinforced concrete cast-in-place piles are a common type of pile used in foundation pit and slope protection. The magnitude and distribution of the earth pressure on the pile sides of reinforced concrete cast-in-place piles play a crucial role in ensuring the safety of foundation pit and slope protection structures and controlling deformation of the surrounding environment. The magnitude of the earth pressure on the pile sides is generally calculated using Coulomb and Rankine theories based on indoor test indicators. However, the calculation results are based on different assumptions and simplifications. Due to the combined influence of multiple factors such as the complexity of the soil and rock, the uneven stiffness of the support system, and excavation conditions, the earth pressure on the pile sides will be redistributed. The actual magnitude and distribution of the earth pressure on the pile sides still differ significantly from the theoretical design calculation results. Therefore, studying the magnitude and distribution of the earth pressure on the pile sides is of great significance for optimizing design and improving design quality.

[0003] Currently, the most common method for measuring lateral earth pressure in cast-in-place piles is direct monitoring. This method involves directly measuring earth pressure using embedded earth pressure cells. Under the premise of minimizing soil disturbance and ensuring accurate measurement, the earth pressure data obtained directly reflects the actual lateral earth pressure acting on the support structure. On-site methods typically include the cloth-hanging method and the borehole method. However, the cloth-hanging method suffers from low survival rates because the bearing surface of the earth pressure cell is easily altered or encased in concrete during concrete pouring. While the borehole method ensures the survival rate and accuracy of the earth pressure cell placement, it only monitors the lateral earth pressure at a certain horizontal distance from the support structure and cannot directly reflect the actual earth pressure acting on the support structure.

[0004] Therefore, it is necessary for the inventors to design a new original testing device to overcome the above problems. Summary of the Invention

[0005] The main objective of this application is to provide an in-situ testing device based on the earth pressure cell for the grouting strip method, so as to solve the problems of low survival rate of testing devices and inaccurate test results in related technologies.

[0006] To achieve the above objectives, this application provides an in-situ testing device based on an earth pressure cell using a grouting strip method, comprising a reinforcing cage, an installation frame fixedly mounted on the reinforcing cage, an earth pressure cell slidably mounted within the installation frame, a directional limiting device fixedly mounted between the installation frame and the earth pressure cell, the sliding direction of the earth pressure cell being the radial direction of the reinforcing cage, and a grouting strip further disposed between the earth pressure cell and the installation frame.

[0007] Optionally, the mounting frame includes a back panel and two side panels, the two side panels being fixedly connected to the left and right ends of the back panel, and the back panel and the two side panels forming a "U" shape.

[0008] Optionally, the back plate is fixedly connected to the steel cage body by welding.

[0009] Optionally, the directional limiting device includes a plurality of directional constraint rods, which are fixedly connected to the side plate and surround the outer wall of the earth pressure box.

[0010] Optionally, there are four directional constraint rods, and the line connecting the four directional constraint rods forms a rectangle and is symmetrically distributed on both sides of the side plates.

[0011] Optionally, the grouting tape is inserted into the gap between the back plate and the earth pressure box.

[0012] Optionally, an exhaust pipe is also fixedly connected to the bottom of the grouting strip, and the distal end of the exhaust pipe extends out of the top of the reinforcing cage.

[0013] Optionally, a ball valve is fixedly installed at the end of the exhaust pipe.

[0014] Optionally, the grouting tape is fixedly connected to the reinforcing cage by binding wire.

[0015] The present invention provides an in-situ testing device for the grouting strip method based on earth pressure cells, which has the following advantages compared with the prior art:

[0016] After the grouting tape is filled with grout, it expands continuously, pushing the earth pressure box towards the borehole wall, eventually making it in close contact with the soil of the borehole wall. This protects the earth pressure box from being encased in concrete, ensuring the effectiveness of the earth pressure box. The earth pressure box is sandwiched between the cast-in-place pile and the surrounding soil, and the three are in close contact, ensuring the transmission path of earth pressure. Attached Figure Description

[0017] The accompanying drawings, which form part of this application, are used to provide a further understanding of the application and to make other features, objects, and advantages of the application more apparent. The illustrative embodiments and descriptions of this application are used to explain the application and do not constitute an undue limitation of the application. In the drawings:

[0018] Figure 1 This is an overall structural diagram of the present invention;

[0019] Figure 2 This is a structural diagram of the pressure box of this utility model;

[0020] Figure 3 This is a structural diagram of the mounting frame of this utility model.

[0021] The components include: 1. Grouting machine; 2. Pressure gauge; 3. Exhaust pipe; 4. Ball valve; 5. Grouting tape; 6. Reinforcing cage; 7. Earth pressure box; 8. Mounting frame; 9. Back plate; 10. Side plate; 11. Orientation restraint bar. Detailed Implementation

[0022] To enable those skilled in the art to better understand the present application, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present application, and not all embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative effort should fall within the scope of protection of the present application.

[0023] It should be noted that the terms "first," "second," etc., used in the specification and accompanying drawings of this application are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be used interchangeably where appropriate for the embodiments of this application described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion; for example, a process, method, system, product, or apparatus that includes a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0024] In this application, the terms "upper," "lower," "left," "right," "front," "rear," "top," "bottom," "inner," "outer," "middle," "vertical," "horizontal," "lateral," and "longitudinal" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. These terms are primarily for the purpose of better describing this application and its embodiments, and are not intended to limit the indicated device, element, or component to having a specific orientation, or to be constructed and operated in a specific orientation.

[0025] Furthermore, in addition to indicating location or positional relationship, some of the aforementioned terms may also have other meanings. For example, the term "above" may also be used in some cases to indicate a certain dependency or connection relationship. Those skilled in the art can understand the specific meaning of these terms in this application based on the specific circumstances.

[0026] In addition, the term "multiple" should mean two or more.

[0027] It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other. This application will now be described in detail with reference to the accompanying drawings and embodiments.

[0028] like Figures 1 to 3 As shown, an in-situ testing device based on an earth pressure cell 7 and a grouting band 5 method includes a reinforcing cage 6, a mounting frame 8 fixedly mounted on the reinforcing cage 6, an earth pressure cell 7 slidably mounted within the mounting frame 8, and a directional limiting device fixedly mounted between the mounting frame 8 and the earth pressure cell 7. The sliding direction of the earth pressure cell 7 is radial to the reinforcing cage 6. A grouting band 5 is also provided between the earth pressure cell 7 and the mounting frame 8. The mounting frame 8 includes a back plate 9 and two side plates 10, with the two side plates 10 fixedly connected to the left and right ends of the back plate 9, forming a "U" shape. The back plate 9 is fixedly connected to the body of the reinforcing cage 6 by welding. The directional limiting device includes multiple directional constraint rods 11, which are fixedly connected to the side plates 10 and surround the outer wall of the earth pressure cell 7. There are four directional constraint rods 11, and the line connecting the four directional constraint rods 11 forms a rectangle and is symmetrically distributed on both sides of the side plates 10. The grouting tape 5 is inserted into the gap between the back plate 9 and the earth pressure box 7. An exhaust pipe 3 is also fixedly connected to the bottom of the grouting tape 5, and the distal end of the exhaust pipe 3 extends out of the top of the reinforcing cage 6. A ball valve 4 is fixedly installed at the end of the exhaust pipe 3. The grouting tape 5 is fixedly connected to the reinforcing cage 6 by tie wire.

[0029] Specifically, an in-situ testing device based on the grouting band 5 method using an earth pressure cell 7 includes a directional translational constraint device, comprising a positioning constraint rod, a back plate 9, and side plates 10. The positioning constraint rod is welded to the periphery of the earth pressure cell 7. The back plate 9 and the two side plates 10 form a "U"-shaped component. The back plate 9 is welded to the designated location of the earth pressure cell 7 in the reinforcing cage 6. The grouting band 5 is laid flat and compacted between the back plate 9 and the earth pressure cell 7. This device can ensure that the grouting band 5 pushes the earth pressure cell 7 to move parallel during the grouting expansion process. Moreover, it can also restrict and protect the earth pressure cell 7 during the subsequent concrete pouring process, reducing the deflection and torsion problems of the earth pressure cell 7.

[0030] The entire device needs to be fixed on the reinforcing cage 6. In actual application, a grouting strip 5 slightly shorter than the length of the reinforcing cage 6 is cut, and the end of the grouting strip 5 is connected to the vent pipe 3. Its main function is to remove air from the grouting strip 5 to ensure that the grouting material is filled tightly. It is required that there is no leakage at the joint. After heating and bending, the vent pipe 3 and the grouting strip 5 are arranged in a U-shape on the tied reinforcing cage 6 and fixed with tie wire. Ball valves 4 are installed at both ends of the device. At the designed position of the earth pressure box 7, the directional translational restraint device is welded. Then the grouting strip 5 is laid flat and placed in, and the earth pressure box 7 is placed in the restraint device. It is ensured that the bearing surface of the earth pressure box 7 is perpendicular to the outside of the reinforcing cage 6. The cable is arranged along the main reinforcement of the reinforcing cage 6 and fixed with tie wire. The installed device is placed into the pile hole together with the reinforcing cage 6. Connect the output port of grouting machine 1 to the interface of grouting tape 5. Inject grout into grouting tape 5 using grouting machine 1. The initial flowability of the grout is designed to be ~s, -s at min, initial setting time ≥h, and final setting time ≤h. After hardening, the grout should be essentially the same as the pile concrete. During construction, the grout gradually fills grouting tape 5 and compresses air to be discharged from exhaust pipe 3. When grout begins to be steadily discharged from exhaust pipe 3, close the end ball valve 4. During grouting, grouting tape 5 continuously expands, pushing earth pressure box 7 towards the borehole wall, eventually making it in close contact with the soil. Once grouting tape 5 reaches fullness at the borehole opening and pressure gauge 2 reaches the specified pressure, close grouting port ball valve 4 to end grouting. Continuous monitoring of earth pressure box 7's readings is conducted throughout the grouting process. After grouting, concrete pouring begins, with careful protection of the cables during pouring. After the concrete hardens, initial data acquisition and real-time measurements during construction are performed.

[0031] The above description is merely a preferred embodiment of this application and is not intended to limit this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. A grouting strip method in-situ testing device based on earth pressure cells, characterized in that: The system includes a reinforcing cage (6), on which an installation frame (8) is fixedly installed. An earth pressure box (7) is slidably installed inside the installation frame (8). A directional limiting device is fixedly installed between the installation frame (8) and the earth pressure box (7). The sliding direction of the earth pressure box (7) is the radial direction of the reinforcing cage (6). A grouting strip (5) is also installed between the earth pressure box (7) and the installation frame (8).

2. The in-situ testing device based on earth pressure cell using the grouting strip method as described in claim 1, characterized in that: The mounting frame (8) includes a back plate (9) and two side plates (10). The two side plates (10) are fixedly connected to the left and right ends of the back plate (9), and the back plate (9) and the two side plates (10) form a "U" shape.

3. The in-situ testing device based on earth pressure cell using the grouting strip method as described in claim 2, characterized in that: The back plate (9) is fixedly connected to the main body of the steel cage (6) by welding.

4. The in-situ testing device based on earth pressure cell using the grouting strip method as described in claim 2, characterized in that: The directional limiting device includes multiple directional constraint rods (11), which are fixedly connected to the side plate (10) and surround the outer wall of the earth pressure box (7).

5. The in-situ testing device based on earth pressure cell using the grouting strip method as described in claim 4, characterized in that: There are four directional constraint rods (11), and the line connecting the four directional constraint rods (11) is rectangular and symmetrically distributed on the side plates (10) on both sides.

6. The in-situ testing device based on earth pressure cell using the grouting strip method as described in claim 2, characterized in that: The grouting strip (5) is inserted into the gap between the back plate (9) and the earth pressure box (7).

7. The in-situ testing device based on earth pressure cell using the grouting strip method as described in claim 1, characterized in that: The bottom of the grouting strip (5) is also fixedly connected to an exhaust pipe (3), the far end of which extends out of the top of the reinforcing cage (6).

8. The in-situ testing device based on earth pressure cell using the grouting strip method as described in claim 7, characterized in that: A ball valve (4) is fixedly installed at the end of the exhaust pipe (3).

9. The in-situ testing device based on earth pressure cell using the grouting strip method as described in claim 7, characterized in that: The grouting strip (5) is fixedly connected to the reinforcing cage (6) by tie wire.

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