One-hole multi-vibrating-wire pore water pressure gauge embedding device

Abstract

The utility model discloses a one-hole multi-vibrating-wire pore water pressure gauge embedding device, relates to the field of civil engineering construction, and mainly aims to solve the problem that the error of test results of vibrating wire pore water pressure gauges at different depths at present is large. The embedded pipe comprises an embedded pipe body, water permeable holes are formed in the pipe wall of the embedded pipe body, a plurality of vertically-arranged sand cushion layers are arranged in the embedded pipe body, an isolating layer is arranged in the embedded pipe body above each sand cushion layer, and a sand filling layer is arranged in the embedded pipe body above the uppermost isolating layer. The pore water pressure gauge is arranged in the sand cushion layer; a permeable layer is fixed on the inner wall of the embedded pipe, the top of the embedded pipe is provided with an installation assembly used for installing the pore water pressure gauge, the installation assembly comprises a foundation beam and an embedded connecting rope connected with the pore water pressure gauge, a cable of the pore water pressure gauge is connected to the foundation beam, and the embedded connecting rope is tied to the foundation beam. The method has the advantage of high test result accuracy.

Description

TECHNICAL FIELD

[0001] The utility model relates to civil engineering construction technical field, concretely relates to a one-hole multi-vibrating string pore water pressure gauge burying device. BACKGROUND

[0002] Pore water pressure is one of the projects frequently observed in geotechnical engineering construction and research, and the vibrating string pore water pressure gauge is a special instrument for testing soil pore water pressure. However, different vibrating string pore water pressure gauge burying methods can greatly affect the test results, the key is to ensure the seepage of the sand cushion layer around the vibrating string pore water pressure gauge probe, and the second is to cut off the downward seepage of the upper part of the drill hole, prevent the upper and lower connection between the vibrating string pore water pressure gauges, and in principle, one vibrating string pore water pressure gauge is buried in one drill hole. However, the disadvantage of burying one vibrating string pore water pressure gauge in one drill hole is that the vibrating string pore water pressure gauges at different depths are greatly different in distance on the plane, and the test results cannot accurately reflect the pore water pressure change law at different depths in the same vertical plane.

[0003] When the traditional one-hole multi-pore water pressure gauge burying method is used, the traditional casing pipe pulling and hole collapsing method is used to seal the pore water pressure gauge, and the upper and lower pore water pressure gauges are easily connected, the pore water pressure values at different depths are almost the same, the test result error is large, and at the same time, in the actual installation process, due to the poor stability of thick layer of silt, the pore water pressure gauge is slowly lowered, and the burying requirement is strict, so it is often impossible to bury the vibrating string pore water pressure gauge to the specified position. If hole cleaning is performed at this time, it is easy to cause hole collapse. Although some technical personnel have improved the vibrating string pore water pressure gauge burying method, the process is often complex in the specific operation process. Therefore, it is of great engineering practical significance to design a reasonable one-hole multi-vibrating string pore water pressure gauge burying device to improve the accuracy of the monitoring results, the burying efficiency and reduce the cost. SUMMARY

[0004] The technical problem to be solved by the utility model is to provide a one-hole multi-vibrating string pore water pressure gauge burying device which can improve the accuracy of the monitoring results, the burying efficiency and reduce the construction cost.

[0005] The purpose of the utility model is achieved in that:

[0006] The one-hole multi-vibrating string pore water pressure gauge burying device comprises a pre-buried pipe, the pre-buried pipe is a PVC pipe, a plurality of water permeable holes are formed in the pipe wall of the pre-buried pipe, a plurality of upper and lower sand cushion layers are arranged in the pre-buried pipe, an isolation layer is arranged above each sand cushion layer, that is, two adjacent sand cushion layers are separated by the isolation layer, and a sand filling layer is arranged above the uppermost isolation layer; the number of sand cushion layers is the same as that of pore water pressure gauges, and the pore water pressure gauges are arranged in the sand cushion layers and wrapped by the sand of the sand cushion layers.

[0007] The water-permeable layer is fixed on the inner wall of the embedded pipe and can be made of geotextile or other materials.

[0008] The embedded pipe is provided with a mounting assembly for installing a pore water pressure gauge at the top of the embedded pipe, the mounting assembly comprises a base beam arranged at the top of the embedded pipe and a pre-embedded connecting rope extending into the embedded pipe and connecting with the pore water pressure gauge through the filling sand layer and the isolation layer, and a cable of the pore water pressure gauge is connected to the base beam.

[0009] A rope ring for mounting the pre-embedded connecting rope is arranged on the base beam, and the pre-embedded connecting rope is connected to the base beam through the rope ring.

[0010] The isolation layer is a bentonite mud ball layer.

[0011] The filling sand layer in the embedded pipe is fine sand, which is smaller in particle diameter than the sand mat layer and can compact the sand mat layer in the embedded pipe.

[0012] The bottom end of the embedded pipe is connected with a drill bit.

[0013] The utility model discloses the advantages are: can effectively realize the setting of multilayer vibrating string type pore water pressure gauge, effectively prevent upper and lower vibrating string type pore water pressure gauge intercommunication, guarantee vibrating string type pore water pressure gauge probe around sand mat layer's seepage unobstructed, solved because thick layer silt stability deficiency leads to conventional burying not standard to lead to test result accuracy not high problem, can effectively overcome one hole more vibrating string type pore water pressure gauge stability is poor, and burying speed is slow and leads to vibrating string type pore water pressure gauge can not bury the predetermined depth problem of the problem. BRIEF DESCRIPTION OF DRAWINGS

[0014] Figure 1 It is the structure schematic diagram of the utility model;

[0015] Figure 2 It is the structure schematic diagram of the embedded pipe in the utility model. DETAILED DESCRIPTION

[0016] The utility model will be further explained in combination with Figure 1 and Figure 2 the utility model;

[0017] The hole multi-vibration string pore water pressure gauge burying device comprises a pre-buried pipe 1, the pre-buried pipe is a PVC pipe, a plurality of water-permeable holes 2 are arranged on the pipe wall of the pre-buried pipe 1, a plurality of upper and lower sand cushion layers 3 are arranged in the pre-buried pipe, an isolation layer 4 is arranged in the pre-buried pipe above each sand cushion layer, that is, two adjacent sand cushion layers are separated by the isolation layer, and a sand filling layer 5 is arranged in the pre-buried pipe above the uppermost isolation layer; and a pore water pressure gauge 6 is arranged in the sand cushion layer.

[0018] The number of sand cushion layers is the same as that of pore water pressure gauges, the pore water pressure gauges are arranged in the sand cushion layers and are wrapped by the sand of the sand cushion layers, so that the pore water pressure gauges can be prevented from contacting the side wall of the pre-buried pipe, and the sand cushion layer adopts medium coarse sand; by arranging the sand cushion layers with different heights in the pre-buried pipe, the multi-layer vibration string pore water pressure gauge can be effectively arranged, and the upper and lower vibration string pore water pressure gauges can be effectively prevented from being connected.

[0019] A water-permeable layer is fixed on the inner wall of the pre-buried pipe, so that the water-permeable holes can ensure water permeation and prevent silt from entering the pre-buried pipe. The water-permeable layer can be a geotextile or the like.

[0020] The pre-buried pipe is provided with a mounting assembly for mounting the pore water pressure gauge on the top of the pre-buried pipe, the mounting assembly comprises a base beam 7 arranged on the top of the pre-buried pipe and a pre-buried connecting rope 8 extending into the pre-buried pipe and connected with the pore water pressure gauge through the sand filling layer and the isolation layer, and a cable 9 of the pore water pressure gauge is connected to the base beam, so that the pore water pressure gauge can be lowered and buried in the pre-buried pipe through the base beam on the upper part of the pre-buried pipe, and the pore water pressure gauge and the cable can be effectively protected from being damaged, the pre-buried pipe provided with the pore water pressure gauge is placed to the pre-buried depth through the pre-buried connecting rope, the pre-buried connecting rope is tied to a relatively firm position of the base beam, and the problem that the pore water pressure gauge is damaged and the buried position is deviated from the predetermined depth due to the compression and consolidation of the backfill soil in the hole after the burying is completed can be effectively avoided.

[0021] A rope ring 10 for mounting the pre-buried connecting rope is arranged on the base beam, and the pre-buried connecting rope is connected with the base beam through the rope ring.

[0022] The isolation layer is a bentonite mud ball layer arranged on the sand cushion layer.

[0023] The sand filling layer in the pre-buried pipe is fine sand, which has a smaller particle diameter than that of the sand cushion layer and can compact the sand cushion layer in the pre-buried pipe.

[0024] The bottom end of the pre-embedded pipe is connected with a drill bit 11, so that the pre-embedded pipe can be conveniently inserted into a drill hole, and the pre-embedded pipe can be more easily inserted into a designated position, and the problem that the device cannot be placed to a predetermined depth due to excessive buoyancy of mud water in the drill hole can be effectively overcome; when being buried, the pre-embedded pipe can be quickly placed to the designated depth by relying on the self weight of the packaged pre-embedded pipe, and the burying time is saved.

[0025] Firstly, the pore water pressure gauge is placed into the pre-embedded pipe at a predetermined position through a pre-embedded connecting rope, then sand and bentonite mud balls are filled into the pre-embedded pipe in sequence, so that the pore water pressure gauge is wrapped by the sand, and the adjacent sand cushion layers are separated by the bentonite mud ball layers, and finally fine sand is filled into the pre-embedded pipe.

[0026] The above is only the preferred embodiment of the present application, and does not limit the patent range of the present application, and any equivalent structure or equivalent process transformation, or direct or indirect application in other related technical fields by using the content of the present application specification and drawings, are also included in the patent protection range of the present application.

Claims

1. A device for embedding a multi-wire pore water pressure gauge, comprising a pre-embedded pipe (1), characterized in that: The wall of the pre-embedded pipe (1) is provided with several water-permeable holes (2), and the pre-embedded pipe is provided with several sand cushion layers (3) arranged vertically. Each sand cushion layer is provided with an isolation layer (4) above the pre-embedded pipe. That is, two adjacent sand cushion layers are separated by the isolation layer. The pre-embedded pipe above the uppermost isolation layer is provided with a filling sand layer (5). A permeable layer is fixed on the inner wall of the pre-embedded pipe; The pore water pressure gauge (6) is located within the sand cushion layer; The top of the pre-embedded pipe is provided with an installation assembly for installing a pore water pressure gauge. The installation assembly includes a foundation beam (7) set on the top of the pre-embedded pipe and a pre-embedded connecting rope (8) extending into the pre-embedded pipe and passing through the filling sand layer and the isolation layer to connect with the pore water pressure gauge. The cable (9) of the pore water pressure gauge is connected to the foundation beam, and the other end of the pre-embedded connecting rope is tied to the foundation beam.

2. The device for embedding a single-hole multi-vibrating-string pore water pressure gauge according to claim 1, characterized in that: The bottom end of the pre-embedded pipe (1) is connected to a drill bit (11).

3. The single-hole multi-vibrating-string pore water pressure gauge installation device according to claim 1 or 2, characterized in that: A rope loop (10) for connecting the pre-embedded connecting rope is provided on the foundation beam, and the pre-embedded connecting rope is connected to the foundation beam through the rope loop.

4. The single-hole multi-vibrating-string pore water pressure gauge installation device according to claim 1 or 2, characterized in that: The isolation layer inside the pre-embedded pipe is a bentonite mud ball layer set on the sand cushion layer.

5. The single-hole multi-vibrating-string pore water pressure gauge installation device according to claim 1 or 2, characterized in that: The filling sand layer inside the pre-embedded pipe is fine sand.

6. The device for embedding a single-hole multi-vibrating-string pore water pressure gauge according to claim 1 or 2, characterized in that: The number of sand cushion layers is the same as the number of pore water pressure gauges.

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