阅读说明：本技术 一种静压式的孔隙水压力测试装置及测试方法 (Static pressure type pore water pressure testing device and testing method ) 是由 周黎月 田丽霞 林杰豹 吴英 陈延峻 于 2020-03-26 设计创作，主要内容包括：一种静压式的孔隙水压力测试装置,包括静力触探仪、静探探杆、孔隙水压力计装置,静力触探仪上安装静探探杆,静探探杆的下端与孔隙水压力计装置连接；孔隙水压力计装置包括孔隙水压力计、静探探杆连接套管、贯入护管、干砂,静探探杆连接套管和贯入护管呈上下布置地活套在孔隙水压力计外且三者可相对轴向移动,静探探杆连接套管的上端与静探探杆连接,贯入护管内填充有可被向上挤出覆盖在孔隙水压力计本体表面的干砂。还提出一种采用该装置实施的孔隙水压力测试方法。本发明避免了钻孔埋设时产生的泥浆,环境卫生,装置结构简单,操作便捷,测试精度高,省时省力,既经济又环保。(A static pressure type pore water pressure testing device comprises a static penetrometer, a static probing rod and a pore water pressure gauge device, wherein the static probing rod is installed on the static penetrometer, and the lower end of the static probing rod is connected with the pore water pressure gauge device; the pore water pressure gauge device comprises a pore water pressure gauge, a static probe rod connecting sleeve, a penetration protection pipe and dry sand, wherein the static probe rod connecting sleeve and the penetration protection pipe are movably sleeved outside the pore water pressure gauge in an up-down arrangement mode and can move axially relatively by the three, the upper end of the static probe rod connecting sleeve is connected with the static probe rod, and the penetration protection pipe is filled with the dry sand which can be upwards extruded and covered on the surface of the pore water pressure gauge body. A pore water pressure testing method implemented by the device is also provided. The invention avoids slurry generated during drilling and burying, has the advantages of environmental sanitation, simple structure, convenient operation, high testing precision, time and labor saving, economy and environmental protection.)

1. A static pressure type pore water pressure testing device is characterized by comprising a static penetrometer, a static probing rod and a pore water pressure gauge device, wherein the static probing rod is installed on the static penetrometer, and the lower end of the static probing rod is connected with the pore water pressure gauge device;

the pore water pressure gauge device comprises a pore water pressure gauge, a static probe rod connecting sleeve, a penetration protective pipe and dry sand, wherein the static probe rod connecting sleeve and the penetration protective pipe are movably sleeved outside the pore water pressure gauge in an up-down arrangement manner, and the pore water pressure gauge, the static probe rod connecting sleeve and the penetration protective pipe can move axially relative to each other;

the pore water pressure gauge comprises a pore water pressure gauge connecting pipe and a pore water pressure gauge body which are connected up and down, wherein the upper end of the pore water pressure gauge connecting pipe is provided with an upper connector and an upper rubber sealing ring, and the lower end of the pore water pressure gauge body is provided with a lower connector and a lower rubber sealing ring;

the upper end of the static probing rod connecting sleeve is connected with the lower end of the static probing rod, the lower end of the static probing rod connecting sleeve is provided with an upper connecting support, the upper connecting support is arranged below the upper connector and the upper rubber sealing ring and limits the upper connector and the upper rubber sealing ring to move downwards in the axial direction, and the upper rubber sealing ring is arranged between the upper connecting support and the upper connector;

the injection protective pipe comprises an upper injection protective pipe, a lower injection protective pipe and an injection head which are sequentially connected from top to bottom, the upper end of the upper injection protective pipe is provided with a lower connecting support, the lower connecting support is arranged above a lower connector and a lower rubber sealing ring, the lower connector and the lower rubber sealing ring are axially moved upwards in a limiting mode, the lower rubber sealing ring is arranged between the lower connecting support and the lower connector, dry sand is filled between the lower connecting support in the injection protective pipe and the lower rubber sealing ring, and the lower connecting support is provided with a hole groove structure for the dry sand to be upwards extruded out of the injection protective pipe.

2. The hydrostatic pore water pressure test device according to claim 1, wherein the upper connection support and the lower connection support are both tapered.

3. The hydrostatic pore water pressure testing device according to claim 2, wherein the bottom surface of the upper connecting support is flush with the lower end pipe orifice of the static probe rod connecting sleeve, and the outer diameter of the bottom surface of the upper connecting support is larger than that of the static probe rod connecting sleeve; the bottom surface of the lower connecting support is flush with the upper end pipe orifice of the upper penetration protective pipe, and the outer diameter of the bottom surface of the lower connecting support is larger than that of the upper penetration protective pipe.

4. The hydrostatic pore water pressure testing device according to claim 1, wherein the pore groove structure is: the inner wall of the lower connecting support is provided with a plurality of bulges which are uniformly distributed along the circumferential direction, the inner wall of the lower connecting support, the plurality of bulges and the outer wall of the pore water pressure gauge enclose a plurality of axially extending holes which are uniformly distributed along the circumferential direction, and dry sand is upwards extruded out of the penetration protection pipe through the holes.

5. The hydrostatic pore water pressure testing device according to claim 1, wherein the upper end of the pore water pressure gauge body is connected with a cable, and the cable is led out from the pore water pressure gauge connecting pipe, the static probe rod connecting sleeve and the static probe rod.

6. The hydrostatic pore water pressure test device of claim 1, wherein the penetration head is tapered.

7. The hydrostatic pore water pressure testing device according to claim 1, wherein the lower end of the pore water pressure gauge connecting pipe is in threaded connection with the upper end of the pore water pressure gauge body, the upper end of the static probe rod connecting sleeve is in threaded connection with the lower end of the static probe rod, and the lower end of the upper penetration protecting pipe is in threaded connection with the upper end of the lower penetration protecting pipe.

8. A pore water pressure testing method, characterized in that the static pressure type pore water pressure testing device of any one of claims 1 to 7 is adopted, and the method comprises the following steps:

(1) arranging a static penetrometer on the test ground, and enabling a static sounding rod to enter a test stratum through the static penetrometer in a static pressing mode step by step until the static penetrometer is embedded to the required depth;

(2) slowly lifting the static sounding rod by a static sounding instrument, lifting the pore water pressure gauge out of the penetration protective pipe, and controlling the lifting length to enable the pore water pressure gauge body to be exposed to be in contact with a tested stratum to perform pore water pressure testing;

(3) after the test is finished, the static sounding probe rod and the pore water pressure gauge device are lifted out together through the static sounding instrument.

9. The method for testing pore water pressure according to claim 8, wherein in the step (2), the static probe rod connecting sleeve and the upper connecting support are lifted up together with the static probe rod, the upper connecting support drives the upper connector to move upwards in the lifting process, and the pore water pressure gauge is further lifted out of the penetration protecting pipe.

10. The pore water pressure test method according to claim 8 or 9, wherein in the step (2), in the process that the pore water pressure gauge is lifted out of the penetration casing, the dry sand penetrating the penetration casing is extruded upwards from the hole groove by the lower rubber sealing ring and covers the surface of the pore water pressure gauge body.

Technical Field

The invention belongs to the technical field of geotechnical engineering testing, and particularly relates to a static pressure type pore water pressure testing device and a testing method.

Background

When the pore water pressure condition in the stratum needs to be known in engineering design and construction, a pore water pressure meter is often buried in the stratum. The testing method mainly comprises the steps of putting down a pore water pressure gauge after a drilling machine forms a hole in advance, and then backfilling. The conventional test method has the following disadvantages: 1. when embedding, holes need to be formed in advance, a drilling machine is adopted for hole pre-forming, then pore water pressure gauge testing equipment is put down and backfilled, the whole process is complicated, and the duration is long; 2. after the pore water pressure gauge is placed, sandy soil filter materials, sealing clay and the like need to be filled, time and labor are wasted, the pore water pressure gauge is damaged, the water-stopping sealing effect of the pore water pressure gauge is difficult to guarantee, and the test accuracy is low; 3. a large amount of slurry is generated in the hole forming process of the drilling machine, so that the environment is polluted; 4. the pore water can not be recovered after being buried under the pressure, thus being not economical and environment-friendly; 5. the test method is complex, and the embedding depth and the accuracy of the test equipment are difficult to guarantee.

Disclosure of Invention

The invention provides a static pressure type pore water pressure testing device and a testing method aiming at the problems.

The purpose of the invention can be realized by the following technical scheme: a static pressure type pore water pressure testing device comprises a static penetrometer, a static probing probe rod and a pore water pressure gauge device, wherein the static probing probe rod is installed on the static penetrometer, and the lower end of the static probing probe rod is connected with the pore water pressure gauge device; the pore water pressure gauge device comprises a pore water pressure gauge, a static probe rod connecting sleeve, a penetration protective pipe and dry sand, wherein the static probe rod connecting sleeve and the penetration protective pipe are movably sleeved outside the pore water pressure gauge in an up-down arrangement manner, and the pore water pressure gauge, the static probe rod connecting sleeve and the penetration protective pipe can move axially relative to each other; the pore water pressure gauge comprises a pore water pressure gauge connecting pipe and a pore water pressure gauge body which are connected up and down, wherein the upper end of the pore water pressure gauge connecting pipe is provided with an upper connector and an upper rubber sealing ring, and the lower end of the pore water pressure gauge body is provided with a lower connector and a lower rubber sealing ring; the upper end of the static probing rod connecting sleeve is connected with the lower end of the static probing rod, the lower end of the static probing rod connecting sleeve is provided with an upper connecting support, the upper connecting support is arranged below the upper connector and the upper rubber sealing ring and limits the upper connector and the upper rubber sealing ring to move downwards in the axial direction, and the upper rubber sealing ring is arranged between the upper connecting support and the upper connector; the injection protective pipe comprises an upper injection protective pipe, a lower injection protective pipe and an injection head which are sequentially connected from top to bottom, the upper end of the upper injection protective pipe is provided with a lower connecting support, the lower connecting support is arranged above a lower connector and a lower rubber sealing ring, the lower connector and the lower rubber sealing ring are axially moved upwards in a limiting mode, the lower rubber sealing ring is arranged between the lower connecting support and the lower connector, dry sand is filled between the lower connecting support in the injection protective pipe and the lower rubber sealing ring, and the lower connecting support is provided with a hole groove structure for the dry sand to be upwards extruded out of the injection protective pipe.

Further, the upper connecting support and the lower connecting support are both conical. Furthermore, the bottom surface of the upper connecting support is flush with the lower end pipe orifice of the static probe rod connecting sleeve, and the outer diameter of the bottom surface of the upper connecting support is larger than that of the static probe rod connecting sleeve; the bottom surface of the lower connecting support is flush with the upper end pipe orifice of the upper penetration protective pipe, and the outer diameter of the bottom surface of the lower connecting support is larger than that of the upper penetration protective pipe.

Further, the hole-groove structure is as follows: the inner wall of the lower connecting support is provided with a plurality of bulges which are uniformly distributed along the circumferential direction, the inner wall of the lower connecting support, the plurality of bulges and the outer wall of the pore water pressure gauge enclose a plurality of axially extending holes which are uniformly distributed along the circumferential direction, and dry sand is upwards extruded out of the penetration protection pipe through the holes.

Furthermore, the upper end of the pore water pressure gauge body is connected with a cable, and the cable is led out from the pore water pressure gauge connecting pipe, the static probing rod connecting sleeve and the static probing rod.

Further, the penetration head is conical.

Furthermore, the lower end of the pore water pressure gauge connecting pipe is in threaded connection with the upper end of the pore water pressure gauge body, the upper end of the static probing rod connecting sleeve is in threaded connection with the lower end of the static probing rod, and the lower end of the upper penetration protecting pipe is in threaded connection with the upper end of the lower penetration protecting pipe.

A pore water pressure testing method adopts the static pressure type pore water pressure testing device, and comprises the following steps:

(1) arranging a static penetrometer on the test ground, and enabling a static sounding rod to enter a test stratum through the static penetrometer in a static pressing mode step by step until the static penetrometer is embedded to the required depth;

(2) slowly lifting the static sounding rod by a static sounding instrument, lifting the pore water pressure gauge out of the penetration protective pipe, and controlling the lifting length to enable the pore water pressure gauge body to be exposed to be in contact with a tested stratum to perform pore water pressure testing;

(3) after the test is finished, the static sounding probe rod and the pore water pressure gauge device are lifted out together through the static sounding instrument.

Furthermore, in the step (2), the static probing rod connecting sleeve and the upper connecting support are lifted together with the static probing rod, the upper connecting support drives the upper connector to move upwards in the lifting process, and the pore water pressure gauge is lifted out of the penetration protective pipe.

Further, in the step (2), in the process that the pore water pressure gauge is lifted out of the penetration protective pipe, the dry sand penetrating into the penetration protective pipe is extruded upwards from the hole groove by the lower rubber sealing ring and covers the surface of the pore water pressure gauge body.

Compared with the prior art, the invention has the beneficial effects that:

(1) the traditional pore water pressure gauge device is modified and connected with the static probing rod, the pore water pressure gauge device is gradually and statically pressed into the soil through the static probing rod by adopting a static penetrometer during embedding, the embedding depth can be accurately controlled as required, and the pore water pressure gauge device can be recovered at any time;

(2) the pore water pressure gauge device adopts a static probe rod connecting sleeve and a penetration protective pipe to match with the static probe rod, and can expose the pore water pressure gauge when the static probe rod is lifted so as to contact with a tested stratum;

(3) the penetration protective pipe of the pore water pressure gauge device can prevent a soil layer from rubbing the pore water pressure gauge in the static pressure process, so that damage is avoided;

(4) rubber sealing rings are respectively arranged at the joints of the two ends of the pore water pressure gauge device and the static probe rod connecting sleeve and the penetration protective pipe, so that sealing filler which needs to be embedded after the original pore forming is omitted, and the requirement on the sealing property of a testing part is met;

(5) the dry sand of the pore water pressure gauge device can cover the surface of the pore water pressure gauge when being extruded, so as to play a role of water permeability, ensure the test effect, save the filter material which needs to be embedded after the original pore forming, and meet the water permeability requirement of the test part;

(6) the design of the upper connecting support on the static probing probe rod connecting sleeve of the pore water pressure gauge device and the lower connecting support on the penetration protective pipe is conical, the contact area between the pore water pressure gauge device and the stratum is increased, the stability of the pore water pressure gauge device is ensured when penetration is facilitated, and when the static probing probe rod is lifted up, the lower connecting support increases the resistance and can keep the penetration protective pipe still, the pore water pressure gauge is convenient to pull up along with the static probing probe rod 2, and therefore the penetration protective pipe is exposed for testing.

(7) The static detection probe rod is adopted, a cable of the pore water pressure gauge is pulled out of the ground from the static detection probe rod and connected with a receiving device, and the static detection probe rod plays a role in protecting the cable.

In conclusion, the invention avoids the slurry generated during drilling and burying, has the advantages of environmental sanitation, simple structure, convenient operation, high testing precision, time and labor saving, economy and environmental protection.

Drawings

Fig. 1 is a schematic view of the overall structure of the present invention.

Fig. 2 is a schematic structural view of the pore water pressure gauge device in the invention when the static probe rod connecting sleeve and the penetration protection pipe are closed.

Fig. 3 is a schematic view of the assembly of the pore water pressure gauge in the present invention.

Fig. 4 is a schematic structural view of the pore water pressure gauge in the present invention when the pore water pressure gauge connecting tube is separated from the pore water pressure gauge body.

Fig. 5 is a schematic structural view of a stationary probe connecting sleeve according to the present invention.

Fig. 6 is an assembly view of the penetration shield according to the present invention.

FIG. 7 is a schematic view of the penetration shield of the present invention with the upper penetration shield separated from the lower penetration shield.

Fig. 8 is a sectional view of a lower connecting bracket in the present invention.

Fig. 9 is a schematic structural view of the pore water pressure gauge device of the present invention when the stationary probe rod connecting sleeve is lifted.

The parts in the figures are numbered as follows:

1 static sounding instrument

2 static probing rod

3 pore water pressure gauge device

4 pore water pressure gauge connecting pipe

5 upper connector

6 go up rubber seal

7 pore water pressure gauge body

8 lower connector

Lower rubber seal ring

10 cable conductor

11 static probe rod connecting sleeve

12 upper connecting support

13 upper penetration protective pipe

14 lower connecting support

15 lower penetration protective pipe

16 penetration head

17 dry sand

18 are convex.

Detailed Description

The following detailed description of the embodiments of the present invention will be given in conjunction with the accompanying drawings to make it clear to those skilled in the art how to practice the present invention. While the invention has been described in connection with preferred embodiments thereof, these embodiments are merely illustrative, and not restrictive, of the scope of the invention.

Referring to fig. 1, the static pressure type pore water pressure testing device comprises a static penetrometer 1, a static probing rod 2 and a pore water pressure gauge device 3. The static sounding instrument 1 is provided with a static sounding probe rod 2, and the lower end of the static sounding probe rod 2 is provided with a pore water pressure gauge device 3.

The pore water pressure gauge device 3 comprises a pore water pressure gauge, a static probe rod connecting sleeve 11, a penetration protective pipe and dry sand 17, and is shown in figure 2. The static probe rod connecting sleeve 11 and the penetration protecting pipe are movably sleeved outside the pore water pressure gauge in an up-down arrangement mode, and the pore water pressure gauge, the static probe rod connecting sleeve 11 and the penetration protecting pipe can move axially relatively.

Referring to fig. 3 and 4, the pore water pressure gauge includes a pore water pressure gauge connecting tube 4 and a pore water pressure gauge body 7 connected up and down. The upper end of the pore water pressure gauge connecting pipe 4 is connected with an upper connector 5, an upper rubber sealing ring 6 is sleeved on the upper connector, and the lower end of the pore water pressure gauge connecting pipe 4 is in threaded connection with the upper end of the pore water pressure gauge body 7. The pore water pressure gauge body 7 is used for detecting pore water pressure, the upper end of the pore water pressure gauge body 7 is connected with a cable 10, the cable 10 is upwards led out from the pore water pressure gauge connecting pipe 4, the static probe rod connecting sleeve 11 and the static probe rod 2, the lower end of the pore water pressure gauge body 7 is connected with a lower connector 8, and a lower rubber sealing ring 9 is sleeved on the lower connector.

Referring to fig. 5, the upper end of the static probing rod connecting sleeve 11 is in threaded connection with the lower end of the static probing rod 2, and the lower end of the static probing rod connecting sleeve 11 is provided with an upper connecting support 12. The upper connecting support 12 is arranged below the upper connector 5 and the upper rubber sealing ring 6, the upper connector 5 and the upper rubber sealing ring 6 are axially moved downwards to be limited, and the upper rubber sealing ring 6 is arranged between the upper connecting support 12 and the upper connector 5 to play a role in sealing water.

Referring to fig. 6 and 7, the penetration protecting pipe includes an upper penetration protecting pipe 13, a lower penetration protecting pipe 15, and a penetration head 16, which are sequentially connected from top to bottom. Go up the upper end of penetrating pillar 13 and install down connection support 14, go up the lower extreme of penetrating pillar 13 and the upper end threaded connection who penetrates pillar 15 down, connect support 14 down and set up in the top of connector 8 and lower rubber seal 9 down to it is spacing to shift up lower connector 8 and lower rubber seal 9 axial, lower rubber seal 9 sets up under and between connection support 14 and the lower connector 8, plays the sealed effect of stagnant water. Wherein, dry sand 17 is filled between the lower connecting support 14 and the lower rubber sealing ring 9 which are penetrated into the protecting pipe, and the dry sand 17 is mainly used for covering the surface of the pore water pressure gauge body 7 and playing the role of a filter material; referring to fig. 8, a hole and groove structure is arranged at the lower connecting support 14 for dry sand 17 to be extruded upwards to the outside of the penetration casing, specifically, a plurality of protrusions 18 are uniformly distributed along the circumferential direction on the inner wall of the lower connecting support 14, a plurality of axially extending holes are formed by the inner wall of the lower connecting support 14, the plurality of protrusions 18 and the outer wall of the pore water pressure gauge in a surrounding manner, and the hole for dry sand 17 to be extruded upwards to the outside of the penetration casing. The lower end of the lower penetration protecting pipe 15 is connected with a conical penetration head 16, and the penetration head 16 is used for penetrating into soil to form a hole.

When assembling the pore water pressure gauge device 3, the pore water pressure gauge is disassembled first, then the penetration protecting pipe is disassembled, the pore water pressure gauge body 7 is arranged in the upper penetration protecting pipe 13, and then the lower penetration protecting pipe 15 is connected with the upper penetration protecting pipe 13. Then, the pore water pressure gauge connecting pipe 4 is arranged in the static probe rod connecting sleeve 11, the pore water pressure gauge connecting pipe 4 is connected with the pore water pressure gauge body 7, and then the dry sand 17 is injected into the injection protective pipe through the pore groove structure. And finally, leading out the cable 10 of the pore water pressure gauge body 7 from the pore water pressure gauge connecting pipe 4, the static probing rod connecting sleeve 11 and the static probing rod 2.

The pore water pressure gauge device 3 has the following two states: referring to fig. 1, when the static probing rod connecting sleeve 11 is closed with the penetration protecting tube, the pore water pressure gauge is located in the static probing rod connecting sleeve 11 and the penetration protecting tube, the upper connector 5 at the upper end of the pore water pressure gauge connecting tube 4 is axially arranged in the static probing rod connecting sleeve 11, the lower connector 8 at the lower end of the pore water pressure gauge body 7 is arranged in the lower penetration protecting tube 15, and dry sand 17 is penetrated into the tube wall gap between the pore water pressure gauge and the penetration protecting tube. Referring to fig. 8, when the static probing rod connecting sleeve 11 is driven to lift up, the upper connecting support 12 at the lower end of the static probing rod connecting sleeve 11 drives the upper connector 5 to lift the pore water pressure gauge out of the penetration protecting tube, and meanwhile, the dry sand 17 penetrating into the protecting tube is extruded upwards from the hole groove structure by the lower rubber sealing ring 9.

Before the test is started, referring to fig. 1, the static penetrometer 1 is arranged on the test ground, the static probe rod 2 is connected with the static probe rod connecting sleeve 11 of the pore water pressure gauge device 3, and the cable 10 of the pore water pressure gauge body 7 is led out from the static probe rod 2.

When a test is carried out, the static sounding rod 2 is gradually and statically pressed into a test stratum through the static penetrometer 1 until the required embedding depth is reached, and in the process, the penetration protective pipe can prevent the pore water pressure gauge from being damaged due to the friction of a soil layer. Then, slowly lift static probe 2 through static penetrometer 1, static probe connecting sleeve 11 and upper junction support 12 are lifted along with static probe 2, upper junction support 12 drives connector 5 to move up at the in-process of being lifted, thereby lift pore water pressure gauge from penetrating the pillar, the length of static probe 2 is lifted in the control, cause pore water pressure gauge body 7 to expose, can realize pore water pressure gauge body 7 and test formation contact and carry out pore water pressure test, at this in-process, dry sand 17 is extruded and is covered on the surface of pore water pressure gauge body 7, play the effect of permeating water of filter material, guarantee test effect.

When the test is finished, the static sounding rod 2 and the pore water pressure gauge device 3 are lifted out together through the static sounding instrument 1, so that the purpose of recovery is achieved.

Wherein, the upper connecting support 12 and the lower connecting support 14 are both conical; the bottom surface of the upper connecting support 12 is flush with a lower end pipe orifice of the static probe rod connecting sleeve 11, the outer diameter of the bottom surface of the upper connecting support 12 is larger than that of the static probe rod connecting sleeve 11, and the inner diameter of the bottom surface of the upper connecting support 12 is smaller than that of the static probe rod connecting sleeve 11; the bottom surface of the lower connecting support 14 is flush with the upper end pipe orifice of the upper penetration protecting pipe 13, the outer diameter of the bottom surface of the lower connecting support 14 is larger than that of the upper penetration protecting pipe 13, and the inner diameter of the bottom surface of the lower connecting support 14 is smaller than that of the upper penetration protecting pipe 13. Design like this has increased the area of contact of pore water pressure gauge device 3 with the stratum, ensure the stability of pore water pressure gauge device 3 when being convenient for to pass through, and when lifting quiet spy probe rod 2, connect support 14 down and increased the resistance and can keep penetrating the pillar motionless, be convenient for the pore water pressure gauge along with pulling out on quiet spy probe rod 2, thereby expose and penetrate the pillar and test, go up and connect support 12 then with last rubber seal 6 close fitting cooperation, play the sealed effect of stagnant water.

It should be noted that many variations and modifications of the embodiments of the present invention fully described are possible and are not to be considered as limited to the specific examples of the above embodiments. The above examples are given by way of illustration of the invention and are not intended to limit the invention. In conclusion, the scope of the present invention should include those changes or substitutions and modifications which are obvious to those of ordinary skill in the art.