A method for measuring the displacement of the top of the foundation pit slope and the shallow soil layer of the slope

Abstract

The present invention discloses a method for measuring the displacement of the top of the foundation pit slope and the shallow soil layer of the slope, belonging to the field of foundation pit safety. It includes determining the number and positions of monitoring points according to the engineering foundation pit design drawings and specifications; simultaneously determining the number and positions of inclinometers in the foundation pit monitoring points; installing the inclinometers, and centering and fixing a 28-mm galvanized round steel on the inclinometer through a 6-mm round steel inside the inclinometer; welding two connecting rods in the transverse and longitudinal directions to the round steel inside the inclinometer and setting the pointers; fabricating the monitoring points, using a 200-mm long galvanized round steel with a diameter of 20 mm to cut a cross mark with a width of 2 mm at the top, and welding the scales in the transverse and longitudinal directions to the monitoring points through flat iron; determining the positions of the scales according to the positions of the pointers determined by the connecting rods, and driving the round steel of the monitoring points into the soil, with 50 mm above the ground; a spirit level is arranged at the top of the inclinometer, and whether the soil body has shifted can be judged according to whether the bubble of the spirit level has shifted. The present invention realizes the rapid monitoring of the changes of the slope top and the shallow soil layer.

Description

Technical Field

[0001] The present invention belongs to the field of foundation pit safety, and particularly relates to a method for measuring the displacement of the top of a foundation pit slope and the shallow soil layer of the slope. Background Art

[0002] With the development of urban construction, major cities around the world have developed and utilized underground spaces for different purposes, such as multi-story basements of high-rise buildings, subways, underground shopping malls, and various underground civil and industrial facilities.

[0003] The increase in the scale and excavation depth of foundation pits has made the problems of deformation and stability of temporary retaining structures complex and prominent, becoming a matter of great concern to the engineering community and municipal management departments. On the one hand, the increase in plane size and excavation depth has caused many new problems that are difficult to solve based on existing theories and experiences; on the other hand, with the increase in the density of various buildings in the city, there are more stringent restrictions on the displacement and adverse effects caused by the excavation of foundation pits and the subsequent construction on the adjacent environment, underground pipelines, and ground traffic. Therefore, it is very important to conduct foundation pit engineering monitoring, especially the monitoring of deep foundation pits during the construction process. Summary of the Invention

[0004] The technical problem to be solved by the present invention is a method for measuring the horizontal displacement of the top of a foundation pit slope and the displacement of the shallow soil layer of the slope, with simple steps and easy operation.

[0005] To solve the above technical problems, the inventor has obtained the technical solution of the present invention through practice and summary. The present invention discloses a method for measuring the displacement of the top of a foundation pit slope and the shallow soil layer of the slope, including the following steps:

[0006] Step 1: Determine the number and positions of monitoring points and detection points according to the design drawings and specifications of the engineering foundation pit.

[0007] Step 2: Determine the number and positions of inclinometers simultaneously according to the foundation pit detection points.

[0008] Step 3: Prefabricate the inclinometer. The inclinometer is provided with multiple sections, and a fixing frame is arranged inside. The fixing frame is fixedly connected to the inclinometer, and a distance measuring member is installed inside the fixing frame.

[0009] A displacement measuring rod is inserted into the middle of the inclinometer, and the head of the displacement measuring rod extends outside the inclinometer. The bottom of the displacement measuring rod is fixedly connected to the bottom of the inclinometer; the distance measuring member detects the distance from the displacement measuring rod inside the inclinometer.

[0010] Step 4: Drive the inclinometer into the detection point, ensuring that the inclinometer is perpendicular to the top of the slope when being driven.

[0011] Step 5: Weld the connecting rod onto the displacement measuring rod. A support rod is installed at one end of the connecting rod away from the inclinometer tube, and the support rod is perpendicular to the connecting rod; a pointing needle is installed at the end of the support rod and the connecting rod.

[0012] Step 6: Fabricate the monitoring pile: Select galvanized round steel and cut a 2 - mm - wide cross mark at the top. Drive the monitoring pile into the top of the slope, leaving 50 mm exposed above the slope top.

[0013] Weld two groups of galvanized flat irons perpendicular to the support rod and the connecting rod at the exposed part. A scale is installed at the ends of the two groups of galvanized flat irons, and the pointing needle points to the zero position of the scale.

[0014] Step 7: A spirit level is set at the top of the inclinometer tube. Determine whether the soil has a vertical displacement according to whether the bubble of the spirit level deviates, and determine whether the soil has a horizontal displacement according to the deviation amount of the detection pointing needle. Determine whether there is a problem with the soil on the foundation pit side or the displacement of the shallow soil layer.

[0015] Specifically, the present invention is used for preliminary detection of the displacement of multiple soil bodies, mainly applied to the situation where the underground structure is relatively loose or complex. The present invention realizes the detection of the levelness and displacement at two points by setting up the monitoring pile and the inclinometer tube. A processing element and a buzzer can be set. When the deviation amount of the ranging sensor reaches the standard, the buzzer alarms to prompt the monitoring personnel of the geological change.

[0016] In a further technical solution, the pointing needle is triangular in shape and is a galvanized flat iron with a thickness of 4 mm, and the height of the pointing needle is lower than the height of the scale.

[0017] In a further technical solution, the inclinometer tube is a rigid PVC tube, and a spirit level is fixedly installed at the top of the displacement measuring rod, and the spirit level is parallel to the connecting rod.

[0018] In a further technical solution, the connecting rod is a 6 - mm galvanized round steel, and the diameter of the monitoring pile is a 20 - mm galvanized round steel.

[0019] In a further technical solution, the fixing frame includes an annular plate. A support part is integrally connected inside the annular plate. The support part is in the shape of an I - beam. The support part is circumferentially arranged inside the annular plate. Installation parts are spaced inside the support part, and a ranging sensor is installed inside the installation part. The output end of the ranging sensor corresponds to the central vertical line of the displacement measuring rod; the displacement measuring rod is inserted into the middle of multiple groups of support parts.

[0020] Compared with the prior art, the present invention can achieve the following technical effects:

[0021] The present invention is used for preliminarily detecting the displacement conditions of multiple soil masses, and is mainly applied to the situations where the underground structure is relatively loose or complex. The present invention realizes the detection of the levelness and offset at two points by setting monitoring piles and inclinometers. A processing element and a buzzer can be set. When the offset amount reaches the standard for the ranging sensor, the buzzer alarms to prompt the monitoring personnel of geological changes.

[0022] A method for measuring the horizontal displacement of the top of a foundation pit slope and the shallow soil mass displacement of the slope of the present invention can more intuitively obtain the relative displacement value between the monitoring point at the top of the slope and the soil mass about 1.5 meters deep in the shallow layer. Then, according to whether the spirit level is offset, it is judged whether the soil mass is offset, and further judged whether it is the change of the shallow soil mass or the displacement value change caused by the monitoring point at the top of the slope. Different from the traditional direct measurement of monitoring data, relevant personnel can obtain whether there is an offset during normal inspections without setting up instruments. For the points with a large displacement exceeding the warning value, instruments can be set up again. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, for those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0024] Figure 1 It is a top view of the installation of the present invention located at the top of the slope;

[0025] Figure 2 It is a side installation schematic diagram of the present invention;

[0026] Figure 3 It is a top view schematic diagram of the ranging member of the present invention;

[0027] In the figure: 1. connecting rod, 2. pointing needle, 3. monitoring pile, 4. support rod, 5. scale, 6. inclinometer, 7. displacement measuring rod, 8. annular plate, 9. spirit level, 10. support part; 11. installation part; 12. ranging sensor. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0028] In order to make the purpose, technical solutions and advantages of the present invention clearer, the following further details the present invention in conjunction with the embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0029] The following further describes the application principle of the present invention in conjunction with the drawings and specific embodiments.

[0030] Embodiment 1

[0031] As Figures 1 to 3As shown, it is an implementation scheme of the present invention, a method for measuring the displacement of the top of the foundation pit slope and the shallow soil layer of the slope, including the following steps:

[0032] Step 1, determine the quantity and positions of the monitoring points and detection points according to the engineering foundation pit design drawings and specifications;

[0033] Step 2, determine the quantity and positions of the inclinometer tubes 6 according to the foundation pit detection points at the same time;

[0034] Step 3, prefabricate the inclinometer tubes 6. The inclinometer tubes 6 are arranged in multiple sections, and a fixing frame is arranged inside. The fixing frame is fixedly connected with the inclinometer tubes 6, and a distance measuring component is installed inside the fixing frame;

[0035] Insert a displacement measuring rod 7 into the middle of the inclinometer tube 6, and the head of the displacement measuring rod 7 extends outside the inclinometer tube 6. The bottom of the displacement measuring rod 7 is fixedly connected with the bottom of the inclinometer tube 6; the distance measuring component detects the distance from the displacement measuring rod 7 inside the inclinometer tube 6;

[0036] Step 4, drive the inclinometer tube 6 into the detection point, ensuring that the inclinometer tube 6 is perpendicular to the top of the slope when driving;

[0037] Step 5, weld the connecting rod 1 on the displacement measuring rod 7. A support rod 4 is installed at one end of the connecting rod 1 away from the inclinometer tube 6, and the support rod 4 is perpendicular to the connecting rod 1; a pointing needle 2 is installed at the end of the support rod 4 and the connecting rod 1;

[0038] Step 6, fabricate the monitoring pile 3: select galvanized round steel and cut a 2mm-wide cross mark at the top, drive the monitoring pile 3 into the top of the slope, and expose 50mm above the top of the slope;

[0039] Weld two groups of galvanized flat irons perpendicular to the support rod 4 and the connecting rod 1 at the exposed part, and a scale 5 is installed at the end of the two groups of galvanized flat irons. The pointing needle 2 points to the zero position of the scale 5;

[0040] Step 7, a level tube 9 is arranged at the top of the inclinometer tube 6. Judge whether the soil body has an up-and-down displacement according to whether the bubble of the level tube 9 deflects, and judge whether the soil body has a horizontal displacement according to the deflection amount of the detection pointing needle 2.

[0041] The pointing needle 2 is triangular in shape and is made of galvanized flat iron with a thickness of 4mm. The height of the pointing needle 2 is lower than the height of the scale 5. The inclinometer tube 6 is a rigid PVC tube. A level tube 9 is fixedly installed at the top of the displacement measuring rod 7, and the level tube 9 is parallel to the connecting rod 1. The connecting rod 1 is a 6mm galvanized round steel, and the diameter of the monitoring pile 3 is 20mm galvanized round steel. The inclinometer tube 6 is a 28mm galvanized steel pipe. This embodiment solves the problem of preliminary detection of the position of the foundation pit slope and the shallow soil layer in the existing technology, which is mainly used for soil quality monitoring near the foundation pit. The detection points can be at relatively complex underground positions or wiring concentrated positions for detection.

[0042] Example 2

[0043] like Figure 3 As shown, it is another implementation scheme of the present invention. On the basis of Example 1, the fixing frame includes an annular plate 8, and a bracket portion 10 is integrally connected to the annular plate 8. The bracket portion 10 is I-shaped and is circumferentially arranged in the annular plate 8. Mounting portions 11 are arranged at intervals in the bracket portion 10. A distance sensor 12 is installed in the mounting portion, and the output end of the distance sensor 12 corresponds to the central vertical line of the displacement measuring rod 7; the displacement measuring rod 7 is inserted in the middle of multiple groups of bracket portions 10.

[0044] The present invention is used for preliminary detection of displacement of multiple soil bodies, and is mainly used in situations where the underground structure is relatively loose or complex. The present invention realizes horizontality and offset detection at two points by setting monitoring piles and inclinometer tubes. Processing elements and buzzers can be set. When the ranging sensor reaches the offset value that meets the standard, the buzzer alarms to remind the monitoring personnel of geological changes.

[0045] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above and that the present invention can be implemented in other specific forms without departing from the spirit or essential features of the present invention. Therefore, the embodiments should be considered exemplary and non-restrictive in all respects, and the scope of the present invention is defined by the appended claims rather than the above description, and it is intended that all changes falling within the meaning and scope of the equivalent elements of the claims be included in the present invention.

[0046] In addition, it should be understood that although the present specification is described according to implementation modes, not every implementation mode contains only one independent technical solution. This description of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment may also be appropriately combined to form other implementation modes that can be understood by those skilled in the art.

Claims

1. A method for measuring the displacement of the top of the foundation pit slope and the shallow soil layer of the slope, characterized in that: It includes the following steps: Step 1, determine the number and positions of the monitoring points and detection points according to the engineering foundation pit design drawings and specifications; Step 2, determine the number and positions of the inclinometers (6) according to the foundation pit detection points at the same time; Step 3, prefabricate the inclinometers (6). The inclinometers (6) are arranged in multiple sections, and a fixing frame is arranged inside. The fixing frame is fixedly connected to the inclinometer (6), and a distance measuring component is installed inside the fixing frame; A displacement measuring rod (7) is inserted into the middle of the inclinometer (6), and the head of the displacement measuring rod (7) extends outside the inclinometer (6). The bottom of the displacement measuring rod (7) is fixedly connected to the bottom of the inclinometer (6); the distance measuring component detects the distance from the displacement measuring rod (7) inside the inclinometer (6); Step 4, drive the inclinometer (6) into the detection point, ensuring that the inclinometer (6) is perpendicular to the top of the slope when being driven; Step 5, weld a connecting rod (1) to the displacement measuring rod (7). A support rod (4) is installed at one end of the connecting rod (1) away from the inclinometer (6). The support rod (4) is perpendicular to the connecting rod (1); a pointing needle (2) is installed at the end of the support rod (4) and the connecting rod (1); Step 6, fabricate the monitoring pile (3): Select galvanized round steel and cut a 2mm-wide cross mark at the top. Drive the monitoring pile (3) into the top of the slope, exposing 50mm above the top of the slope; Weld two groups of galvanized flat irons perpendicular to the support rod (4) and the connecting rod (1) at the exposed part. A scale (5) is installed at the ends of the two groups of galvanized flat irons. The pointing needle (2) points to the zero position of the scale (5); Step 7, a spirit level (9) is arranged at the top of the inclinometer (6). Judge whether the soil body has an up-and-down displacement according to whether the bubble of the spirit level (9) deflects, and judge whether the soil body has a horizontal displacement according to the deflection amount of the detection pointing needle (2).

2. A method for measuring the displacement of the top of the foundation pit slope and the shallow soil layer of the slope according to claim 1, characterized in that: The pointing needle (2) is triangular in shape and is a galvanized flat iron with a thickness of 4mm. The height of the pointing needle (2) is lower than the height of the scale (5).

3. A method for measuring the displacement of the top of the foundation pit slope and the shallow soil layer of the slope according to claim 1, characterized in that: The inclinometer (6) is a rigid PVC pipe. A spirit level (9) is fixedly installed at the top of the displacement measuring rod (7). The spirit level (9) is parallel to the connecting rod (1).

4. A method for measuring the displacement of the top of the foundation pit slope and the shallow soil layer of the slope according to claim 1, characterized in that: The connecting rod (1) is a 6mm galvanized round steel, and the diameter of the monitoring pile (3) is 20mm galvanized round steel.

5. A method for measuring the displacement of the top of the foundation pit slope and the shallow soil layer of the slope according to claim 1, characterized in that: The fixing bracket includes an annular plate (8), and a bracket part (10) is integrally connected inside the annular plate (8). The bracket part (10) is in an I shape, and the bracket part (10) is circumferentially arranged inside the annular plate (8). Installation parts (11) are arranged at intervals inside the bracket part (10), and a ranging sensor (12) is installed inside the installation part. The output end of the ranging sensor (12) corresponds to the central vertical line of the displacement measuring rod (7); the displacement measuring rod (7) is inserted into the middle of multiple groups of bracket parts (10).

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