CN112609672A

CN112609672A - Prevention and treatment remediation method for directional drilling pipeline to penetrate through soft dike foundation

Info

Publication number: CN112609672A
Application number: CN201910946527.6A
Authority: CN
Inventors: 叶合欣; 叶济华; 袁以美
Original assignee: Individual
Current assignee: Individual
Priority date: 2019-10-05
Filing date: 2019-10-05
Publication date: 2021-04-06

Abstract

The invention discloses a prevention and cure remediation method for a directional drilling pipeline to pass through a soft embankment foundation, which comprises the following steps: the construction method comprises the steps of integrally reinforcing a dike foundation of a dike body before construction, monitoring seepage and settlement deformation in a construction period, grouting the annular part at the periphery of a pipeline after pipe dragging, filling and grouting along two sides of the pipeline after pipe dragging, backfilling and preventing seepage for a drilled soil-out point and a working well after construction, monitoring seepage and settlement deformation in a running period for a long time, and grouting and scrapping in the pipeline when the use is due. The invention has the advantages of pre-reinforcement prevention, whole process monitoring, post-remediation, proper scrapping after the use is over and the like, and ensures the safety and stability of the dike passed by the pipeline.

Description

Prevention and treatment remediation method for directional drilling pipeline to penetrate through soft dike foundation

Technical Field

The invention relates to a prevention and cure remediation method for a pipeline crossing a dike foundation, in particular to a prevention and cure remediation method for a directional drilling pipeline crossing a soft dike foundation.

Background

The water, oil and gas pipelines are generally hundreds of thousands of meters long and inevitably pass through river channels on the way. The directional drilling construction can realize that the pipeline passes through the river channel from the river bottom. Compared with the method for binding and setting the pipe trench dug in the open at the bottom of the river and the bridge built on the water, the directional drilling construction method has the advantages of quick construction, no need of arranging cofferdams, less investment, less adverse effect on the river channel, no obstruction to flood discharge and the like, and is increasingly widely applied when the pipeline passes through the river channel.

The crossing pipeline has great disturbance and destruction effects on nearby strata, and has adverse effects on embankment seepage, anti-slip stability and the like.

The existing treatment method is to backfill cohesive soil at an earth-penetrating point, an earth-discharging point and a working well of the directional drilling. This simple treatment is also possible across rock foundations. When the base of the through embankment is soft silt or mucky soil, if the base is not properly treated, serious harm is caused to the safety and stability of the embankment. This is mainly reflected in seepage, stability, differential settlement and deformation, and so on, and therefore, a thorough prevention and remedy method needs to be considered.

Therefore, the method for preventing and remedying the directional drilling pipeline penetrating through the weak embankment foundation has the advantages of pre-reinforcement prevention, whole-process monitoring, post-remediation, proper scrapping after the use is over and the like, and ensures the safety and stability of the embankment penetrated by the pipeline.

Disclosure of Invention

The invention aims to overcome the defects in the prior art, provides a method for preventing and remedying the directional drilling pipeline passing through the weak embankment foundation, has the advantages of pre-reinforcement prevention, whole-process monitoring, post remediation, proper scrapping after the use is over and the like, and ensures the safety and stability of the passing embankment.

In order to achieve the purpose, the technical scheme of the invention is as follows:

the method comprises the steps of integrally reinforcing a dike foundation of a dike body before construction, monitoring seepage and settlement deformation in a construction period, grouting the annular part at the periphery of a pipeline after pipe dragging, filling and grouting along two sides of the pipeline after pipe dragging, preventing seepage of drilled-in soil-out points and backfilled clay of a working well after construction, monitoring seepage and settlement deformation in a running period, and grouting and scrapping in the pipeline when the use is due.

The invention has the advantages of pre-reinforcement prevention, whole process monitoring, post-remediation, proper scrapping after the use is over and the like, and ensures the safety and stability of the dike passed by the pipeline.

A prevention and cure remediation method for a directional drilling pipeline to penetrate through a weak embankment is characterized by comprising the following steps:

integral reinforcement of dike foundation of S1 construction front dike body

For the dike sections of weak soil layers such as dike foundation with loose filling soil, filling soil quality not meeting the specification requirements and dike foundation with sludge or mucky soil, an integral reinforcement measure is adopted before the pipeline crossing construction, so that the pipeline crosses in the integrally reinforced stratum. The early reinforcement has the following advantages: when the dike needs to be reinforced up to the standard after several years, the design and implementation of the dike reinforcing scheme cannot be influenced by the buried pipe below the dike foundation surface.

Preferably, the embankment body dyke foundation is integrally reinforced before construction, and the range on the plane is as follows: the diameter of the pipe is 5-10 times of the diameter of the foot line of the bank from the front of the bank to the normal water level at the side close to the water or the river level at the time of reinforcing construction and from the back of the bank to the bank foot line at the side opposite to the water.

Preferably, the reinforcement depth on the vertical surface is: entering 5m below the designed pipe bottom elevation. The reinforcing measures are as follows: the cement soil mixing piles are arranged in a full-scale red mode, the pile diameter is 0.5m, and the pile spacing is 2.0 m.

S2 seepage and sedimentation deformation monitoring in construction period

During construction, slurry pressure can cause surface slurry leakage and surface uplift, and hidden troubles of surface deformation and centralized leakage exist. Therefore, settlement, displacement and seepage monitoring points need to be arranged. When the abnormal condition is found, appropriate treatment measures should be taken in time.

Preferably, the monitoring points are distributed on the top of the dike and the dike slope on the side close to the back water, and the range is 50m between the upstream and the downstream of the pipeline.

Grouting for outer annular part of pipe after S3 pipe dragging

Pressure grouting is carried out on the peripheral annular position of the pipeline after the directional drilling of the dragging pipe, so that the cavity volume can be effectively reduced, and effective remedial measures are taken for ensuring the safety of an embankment. The grouting range comprises the pipe section passing through the dike and the management range thereof and the pipe section passing through the strong permeable layer, and when the conditions permit, the full-section grouting is preferred.

Preferably, before the pipeline is pulled back, the grouting pipe is bound on the periphery of the pipeline, and the grouting hole is only formed in the length range of 2-4m at the bottom of the grouting pipe. In order to improve the grouting effect, the grouting pipes can be divided into 4-6 pipes which are uniformly arranged on the outer wall of the pipeline, and grouting holes are formed along the pipeline in groups and sections. The grouting material is cement mortar.

S4 filling and grouting on two sides of pipeline at rear edge of towing pipe

And after the pipeline dragging construction is finished, filling and grouting are carried out on the ground surface along two sides of the pipeline.

Preferably, the grouting range on the plane is as follows: land area from the point of drill-in to the point of drill-out; the grouting depth on the vertical surface is 5m below the bottom of the pipeline.

Preferably, the reinforcement means is: and (3) grouting bentonite, arranging 2 rows along the pipeline, wherein the pile diameter is 0.5m, and the pile distance is 2.0 m.

S5 backfilling seepage-proofing method for drilling-in and unearthing points and working wells after construction

Drilling in a soil-out point and a working well are weak links of seepage damage, and appropriate reinforcement measures should be taken after construction. The method comprises the steps of firstly putting a slope to a designed section at a working well and a drilling-in and unearthing point, pouring a concrete cut-off wall on the periphery of a pipeline, and arranging a rubber ring pad between a pipe and concrete for seepage prevention. Filling clay to a designed height, backfilling undisturbed soil, and ensuring that the compaction degree is not less than 0.95. And leveling the earth surface and recovering to the original shape.

S6 seepage and sedimentation deformation monitoring during operation

The slurry is solidified and retracted in the operation period, and hidden troubles of ground settlement and concentrated leakage exist. Therefore, settlement, displacement and seepage monitoring points need to be arranged and monitored for a long time. When the abnormal condition is found, appropriate treatment measures should be taken in time.

S7 abandonment of grouting in pipe when use is due

When the pipeline is used due, the gate valves at the two ends are cut off, bentonite slurry is filled in the pipeline, and concrete is used for plugging the port of the pipeline.

Advantageous effects

1. The affected section is integrally reinforced, and the prevention effect is achieved in advance.

2. The pipe periphery annular space position is grouted the reinforcement, prevents to produce and concentrates the seepage passageway.

3. The whole process monitoring is carried out in all directions in the operation period, so that the abnormal conditions can be mastered in time, and the treatment measures can be taken in time.

4. After which the pipeline is properly treated.

Drawings

FIG. 1 is a method for implementing the prevention and cure remedy method for the directional drilling pipeline crossing the soft embankment foundation;

FIG. 2 is a longitudinal section of the river crossing pipeline of the directional drilling pipeline of the embodiment;

FIG. 3 is a plan view of the embodiment for the early reinforcement of the dyke body dyke foundation;

FIG. 4 is a longitudinal sectional view of an early reinforcement of the dyke body of an embodiment;

FIG. 5 is a cross-sectional view of an embodiment pre-reinforcing embankment segment;

FIG. 6 is a plan view of the monitoring point during construction and operation of the embodiment.

FIG. 7 is a sectional view of grouting at the annular position of the periphery of the pipeline after pipe dragging of the embodiment;

FIG. 8 is a plan view of the rear edge of the pipe filled with grout of the embodiment;

FIG. 9 is a longitudinal section of the pipe after the pipe is pulled and filled with grout along two sides of the pipe according to the embodiment;

FIG. 10 is a cross-sectional view of the grouting embankment section along both sides of the pipeline after construction according to the embodiment;

FIG. 11 is a longitudinal cross-sectional view of the embodiment of the anti-seepage working well at the point of excavation;

FIG. 12 is an anti-seepage cross-sectional view of an embodiment of a work well drilled into a soil removal point.

Description of reference numerals:

1-directionally drilling a pipeline, 2-a working well, 3-an earth entering point, 4-an earth discharging point, 5-a dike, 501-a dike foundation surface, 6-a dike management range boundary line, 7-a dike body section pipeline burial depth, 8-a riverbed section pipeline burial depth, 9-a cement mixing pile, 10-a river level, 11-backfilling clay, 12-backfilling undisturbed soil, 13-a concrete seepage intercepting wall, 14-a rubber ring pad, 21-a final hole in front of a dragging pipe, 22-a grouting pipe, 23-an annulus part and 30-a monitoring point.

Detailed Description

The present invention will be described in further detail with reference to examples and drawings, but the present invention is not limited thereto.

The embodiment discloses a prevention and cure remediation method for a directional drilling pipeline to pass through a soft embankment base (fig. 1-2), which comprises the following steps: the method comprises the steps of integrally reinforcing a dyke foundation 5 of a dike body before construction by using a cement soil mixing pile 9, monitoring seepage and settlement deformation 30 in the construction period, grouting an annular space 23 at the periphery of a pipeline 1 after pipe dragging, filling and grouting along two sides of the pipeline 1 after pipe dragging, preventing seepage of a drilling-in soil point 3, a soil-out point 4 and a backfilling clay 11 of a working well 2 after construction, monitoring seepage and settlement deformation in the operation period, and grouting and scrapping in the pipeline when the use is due.

In the embodiment, the method of reinforcing prevention in advance, monitoring the whole process, remedying after events, scrapping properly after the use is over and the like is adopted, so that the safety and the stability of the dike passed by the pipeline are ensured.

The method comprises the following steps:

step 1. integral reinforcement of dyke body and dyke foundation before construction (fig. 3-5)

Preferably, the embankment body dyke foundation is integrally reinforced before construction, and the range on the plane is as follows: the diameter of the pipe is 5-10 times of the diameter of the foot line of the bank from the front of the bank to the normal water level at the side close to the water or the river level at the time of reinforcing construction and from the back of the bank to the bank foot line at the side opposite to the water. The reinforcement depth on the vertical surface is as follows: entering 5m below the designed pipe bottom elevation.

Preferably, the reinforcement means is: the cement soil mixing piles are arranged in a full-scale red mode, the pile diameter is 0.5m, and the pile spacing is 2.0 m.

Step 2. monitoring seepage and settlement deformation in construction period (fig. 6)

Step 3, grouting the peripheral annular space of the pipeline after pipe dragging (figure 7)

Step 4, filling grouting on two sides of the rear edge of the pipe (figure 8-figure 10)

Preferably, the grouting range on the plane is as follows: land area from the point of drill-in to the point of drill-out; the grouting depth on the vertical surface is 5m below the bottom of the pipeline. The reinforcing measures are as follows: and (3) grouting bentonite, arranging 2 rows along the pipeline, wherein the pile diameter is 0.5m, and the pile distance is 2.0 m.

Step 5. anti-seepage to the drilling unearthed point and the backfill of the working well after construction (figure 11-figure 12)

Drilling in a soil-out point and a working well are weak links of seepage damage, and appropriate reinforcement measures should be taken after construction. The method comprises the steps of firstly putting a slope to a designed section at a working well and a drilling-in and unearthing point, pouring a concrete cut-off wall on the periphery of a pipe, and arranging a rubber ring gasket between the pipe and the concrete for seepage prevention. Filling clay to a designed height, backfilling undisturbed soil, and ensuring that the compaction degree is not less than 0.95. And leveling the earth surface and recovering to the original shape.

Step 6. seepage and settlement deformation monitoring during operation (FIG. 6)

Step 7, the grouting in the pipe is scrapped when the use is due

The above embodiments are preferred embodiments of the present invention, but the present invention is not limited to the above embodiments, and any other changes, modifications, substitutions, combinations, and simplifications which do not depart from the spirit and principle of the present invention should be construed as equivalents thereof, and all such changes, modifications, substitutions, combinations, and simplifications are intended to be included in the scope of the present invention.

Claims

1. A method for preventing and remedying the directional drilling pipeline penetrating through a weak embankment foundation is characterized by integrally reinforcing the embankment foundation of a dyke body before construction, monitoring seepage and settlement deformation in a construction period, grouting the annular part at the periphery of the pipeline after pipe dragging, filling and grouting along two sides of the pipeline after the pipe dragging, backfilling a drilling-in soil outlet point and a working well for seepage prevention after construction, monitoring seepage and settlement deformation in a long term in a running period, and discarding grouting in the pipeline when the use is due.

2. The method as claimed in claim 1, wherein the dyke body is reinforced before construction, the range on the plane is from the front of the dyke to the normal water level at the waterside side or the river level at the time of reinforcing construction, the range on the plane is from the back of the dyke to the baseboard at the waterside, the pipe diameter is 5-10 times along the two sides of the pipeline axis, the reinforcing depth on the vertical surface is 5m below the designed pipe bottom elevation, cement soil mixing piles are arranged in a full-scale red mode, the pile diameter is 0.5m, and the pile spacing is 2.0 m.

3. The method for preventing and remedying the directional drilling pipeline crossing the soft embankment foundation according to claim 1, wherein the seepage and settlement deformation monitoring during the construction period is carried out, and monitoring points are distributed on the embankment top and the upstream and downstream embankment slopes of the pipeline within 50 m.

4. The method for preventing and remedying the directional drilling pipeline penetrating through the soft embankment foundation according to claim 1, wherein the annulus part on the periphery of the pipeline is grouted after the pipeline is pulled, the grouting range comprises a pipe section penetrating through the embankment and the management range thereof and a pipe section penetrating through a strong permeable layer, the grouting pipe is bound on the periphery of the pipeline before the pipeline is pulled back, grouting holes are formed only in the length range of 2-4m at the bottom of the grouting pipe, the grouting pipe is divided into 4-6 pieces and uniformly arranged on the outer wall of the pipeline, the grouting holes are formed in sections along the pipeline, and the grouting material is cement mortar.

5. The method for preventing and remedying the soft dike foundation penetrated by the directional drilling pipeline according to claim 1, wherein the towing pipe is filled and grouted along two sides of the pipeline at the back, the ground surface is filled and grouted along two sides of the pipeline after the construction of the towing pipe of the pipeline is completed, the grouting range on the plane is a land region from a drilling point to a drilling point, the grouting depth on the vertical surface is 5m below the bottom of the pipeline, bentonite is grouted, 2 rows are arranged along the pipeline, the pile diameter is 0.5m, and the pile distance is 2.0 m.

6. The method for preventing and remedying the soft embankment foundation penetrated by the directional drilling pipeline according to claim 1, wherein the construction is followed by backfilling and seepage-proofing of a drilled soil outlet point and a working well, slope-releasing to a designed section, pouring a concrete cut-off wall on the periphery of the pipe, arranging a rubber gasket between the pipe and the concrete for seepage-proofing, filling clay to a designed height, backfilling with undisturbed soil, compacting degree of not less than 0.95, and leveling the earth surface and recovering to the original shape.

7. The method as claimed in claim 1, wherein the seepage and settlement during operation are monitored for a long period, and the monitoring points are distributed on the top of the embankment and the embankment slope on the side facing the back water within 50m of the upstream and downstream of the pipeline.

8. The method as claimed in claim 1, wherein the grouting is discarded when the use of the pipe is due, and when the use of the pipe is due, the gate valves at two ends are cut off, bentonite slurry is filled in the pipe, and concrete is used for sealing the port of the pipe.