阅读说明：本技术 地表超深孔定向控域注浆施工方法 (Directional area control grouting construction method for surface ultra-deep hole ) 是由 刘赪 谢君泰 陈海军 王飞 于介 靳宝成 孙国庆 吴昆朝 张亮 单红雨 邹明波 于 2021-05-14 设计创作，主要内容包括：本发明公开了一种地表超深孔定向控域注浆施工方法,包括：按照设定的尺寸要求制作靶向注浆阀管；平整施工场地,测量、标定、并钻置若干个注浆孔的位置；将靶向注浆阀管与PE管一起吊装至其中一个注浆孔内,将内混合注浆塞通过打压管与压力泵相连接,并通过提升钢绳与卷扬系统相连接,将内混合注浆塞及注浆芯管置入靶向注浆阀管内,下降至预注浆的深度；通过PE管向注浆孔内注入套壳料；将注浆芯管连接好注浆管路,通过内混合注浆塞实施后退式分段注浆；以及待一段注浆完成后,起拔内混合注浆塞至下一注浆段落,重复上述步骤,直至完成注浆孔的全部注浆段落。(The invention discloses a surface ultra-deep hole directional controlled-area grouting construction method, which comprises the following steps: manufacturing a targeted grouting valve pipe according to a set size requirement; leveling a construction site, measuring, calibrating and drilling the positions of a plurality of grouting holes; hoisting the target grouting valve pipe and the PE pipe into one grouting hole, connecting an inner mixed grouting plug with a pressure pump through a pressure pipe, connecting the inner mixed grouting plug with a winch system through a lifting steel rope, placing the inner mixed grouting plug and a grouting core pipe into the target grouting valve pipe, and descending to the depth of pre-grouting; injecting a shell material into the grouting hole through the PE pipe; connecting the grouting core pipe with a grouting pipeline, and implementing retreating type sectional grouting through an internal mixing grouting plug; and after one section of grouting is finished, pulling the inner mixed grouting plug to the next grouting section, and repeating the steps until all grouting sections of the grouting hole are finished.)

1. A surface ultra-deep hole directional controlled-area grouting construction method comprises the following steps:

(1) manufacturing a targeted grouting valve pipe according to a set size requirement;

(2) leveling a construction site, measuring and calibrating the positions of a plurality of grouting holes, and sequentially drilling to set hole depths at the calibrated positions to complete all drilling of the grouting holes;

(3) hoisting the targeted grouting valve pipe and the PE pipe into one of the grouting holes together, and injecting casing material into the grouting holes through the PE pipe so as to close a gap between the targeted grouting valve pipe and the hole wall of the grouting hole;

(4) connecting an inner mixed grouting plug with a pressure pump through a pressure pipe, connecting the inner mixed grouting plug with a winch system through a lifting steel rope, connecting a grouting core pipe with the inner mixed grouting plug, placing the grouting core pipe and the inner mixed grouting plug into the targeted grouting valve pipe, descending the grouting core pipe to the depth of pre-grouting, expanding the inner mixed grouting plug through the pressure pipe by using the pressure pump, connecting the grouting core pipe with a grouting pipeline, and performing retreat type sectional grouting through the inner mixed grouting plug; and

(5) and after one section of grouting is finished, pulling the inner mixing grouting plug to the next grouting section, and repeating the step (4) until all grouting sections of the grouting hole are finished.

2. The earth surface ultra-deep hole directional control field grouting construction method as claimed in claim 1, wherein in step (1), a plurality of rows of grout overflow holes are annularly arranged on the pipe wall of the targeted grouting valve pipe, and a grout stopping valve sleeve protector are sleeved on each row of grout overflow holes; the targeted grouting valve pipe comprises a first type targeted grouting valve pipe and a plurality of second type targeted grouting valve pipes, the first type targeted grouting valve pipe is identical to the second type targeted grouting valve pipe in diameter and wall thickness, one end of the first type targeted grouting valve pipe is provided with a guide tip, the other end of the first type targeted grouting valve pipe is provided with an outer/inner screw thread, and two ends of the second type targeted grouting valve pipe are respectively provided with an inner screw thread and an outer screw thread.

3. The surface ultra-deep hole directional controlled-area grouting construction method according to claim 2, characterized in that an outer casing pipe joint is welded at the joint of the two second type targeted grouting valve pipes, the length of the outer casing pipe joint is not less than 60 cm, and the inner diameter of the outer casing pipe joint is not more than 3 mm of the outer diameter of the targeted valve pipes.

4. The surface ultra-deep hole directional controlled-area grouting construction method according to claim 3, characterized in that in the step (1), the outer diameter of the targeted grouting valve pipe is set to be 60 mm, 79 mm or 89 mm.

5. The surface ultra-deep hole directional controlled-area grouting construction method according to claim 4, characterized in that in the step (2), the depth of the grouting hole is set to be 60-300 m.

6. The surface ultra-deep hole directional controlled-area grouting construction method according to claim 5, characterized in that in the step (2), the drilling mode is set to high-pressure wind hole forming, water drilling hole forming or mud wall protection hole forming.

7. The surface ultra-deep hole directional controlled-area grouting construction method according to claim 6, characterized in that in the step (3), the casing material is composed of the following raw materials in parts by weight: 100 parts of water, 100-200 parts of cement and 100-300 parts of bentonite.

8. The earth surface ultra-deep hole directional controlled-area grouting construction method according to claim 7, characterized in that in the step (4), a grouting core pipe or two grouting core pipes are provided, and the diameter of the grouting core pipe is set to be 15 mm or 20 mm.

9. The surface ultra-deep hole directional controlled-area grouting construction method according to claim 6, characterized in that in the step (4), the grouting liquid is sulphoaluminate cement single-liquid slurry, modified common cement single-liquid slurry or cement-water glass double-liquid slurry.

10. The surface ultra-deep hole directional controlled-area grouting construction method according to claim 9, characterized in that in the step (4), the segment length of the grouting section is set to be 0.75-2 m, and the grouting pressure is set to be 1-30 MPa.

Technical Field

The invention belongs to the field of surface advanced pre-reinforcement, and particularly relates to a grouting pre-reinforcement construction method for poor geology of a medium-deep buried tunnel.

Background

The earth surface grouting technology frequently used in tunnel engineering has the grouting depth within 60 meters mostly, and for the measure of advanced pre-reinforcement of a tunnel buried in a medium-deep complex geological structure, the excavation construction is mostly carried out by adopting a step method, a middle partition wall pilot tunnel method, a CRD method and other construction methods, but the construction procedures of the construction methods are complicated, the problems of tunnel face collapse and structural deformation cannot be avoided, the construction risk is extremely high, the progress is slow, and the construction cost is high.

In order to ensure construction safety and stable structure, at present, a tunnel curtain grouting process is mostly adopted for the advanced pre-reinforcement measure aiming at poor geology of a medium-deep buried tunnel, but during tunnel curtain grouting construction, grouting, excavation and reservation are needed for one section, the working face is operated in a single process, circulation reinforcement is carried out for 20-30 meters, excavation is carried out for 15-25 meters, grouting reinforcement and tunnel excavation construction cannot be carried out simultaneously, the tunnel footage is only 15-20 meters every month, construction time is long, and stealth cost is high.

The technical scheme is that the grouting structure comprises a drill hole formed in the ground surface, a sleeve valve pipe is arranged in the drill hole, a stopper is arranged in the sleeve valve pipe, a closed mixing cavity is formed between the stopper and the bottom of the sleeve valve pipe, a first grouting pipe and a second grouting pipe which are communicated with the mixing cavity are arranged in the drill hole, grouting holes are formed in the inner wall of the mixing cavity, a leather sleeve for plugging the grouting holes is hooped at the positions, corresponding to the grouting holes, of the sleeve valve pipe, the stopper is used for plugging to form the closed mixing cavity, and therefore cement paste and water glass paste can be injected into the mixing cavity through the first grouting pipe and the second grouting pipe respectively to be mixed. However, the grouting method for surface ultra-deep hole double-slurry grouting has the following defects or shortcomings: (1) the grouting pipe has a complex structure, high grouting difficulty and long grouting process time; (2) grouting reinforcement and tunnel excavation construction cannot be simultaneously constructed.

Therefore, the earth surface ultra-deep hole directional controlled area grouting construction method which is suitable for pre-reinforcing in-advance and deeply burying the unfavorable geology of the tunnel, meets the requirements of safe construction of the tunnel, controls structural deformation and obviously improves the tunnel construction progress is a problem which is urgently needed to be solved in the industry.

Disclosure of Invention

The invention aims to provide a construction method for ground surface ultra-deep hole directional domain control grouting (DDK technology for short), which realizes the advanced precise targeted grouting pre-reinforcement construction of the ground surface on poor geology in front of a tunnel face under the condition of deep burying in a tunnel by changing grouting equipment, grouting materials, a grouting method and a grouting process, realizes the safe construction of the tunnel, controls the structural deformation, improves the tunnel construction progress and provides a new choice for grouting reinforcement of a deeper tunnel weak stratum in the industry.

In order to achieve the purpose, the invention provides a surface ultra-deep hole directional controlled-field grouting construction method, which comprises the following steps: (1) manufacturing a targeted grouting valve pipe according to a set size requirement; (2) leveling the construction site, measuring and calibrating the positions of a plurality of grouting holes, and drilling to the set hole depth at the calibrated positions in sequence to finish drilling of all the grouting holes; (3) hoisting the targeted grouting valve pipe and the PE pipe into one grouting hole, and injecting casing materials into the grouting hole through the PE pipe so as to close a gap between the targeted grouting valve pipe and the hole wall of the grouting hole; (4) connecting the inner mixed grouting plug with a pressure pump through a pressure pipe, connecting the inner mixed grouting plug with a winch system through a lifting steel rope, connecting the grouting core pipe with the inner mixed grouting plug, placing the grouting core pipe into a targeted grouting valve pipe, descending the grouting valve pipe to the depth of pre-grouting, expanding the inner mixed grouting plug through the pressure pipe by using the pressure pump, connecting the grouting core pipe with a grouting pipeline, and implementing backward type sectional grouting through the inner mixed grouting plug; and (5) after one section of grouting is finished, pulling the inner mixed grouting plug to the next grouting section, and repeating the step (4) until all grouting sections of the grouting hole are finished.

The surface ultra-deep hole directional controlled-area grouting construction method can meet the requirement of targeted grouting construction with the hole depth within the range of 60-300 m.

Optionally, in the step (1), a plurality of rows of grout overflow holes are annularly arranged on the pipe wall of the targeting grouting valve pipe, and a grout stopping valve sleeve protector are sleeved on each row of grout overflow holes; the targeted grouting valve pipe comprises a first type targeted grouting valve pipe and a plurality of second type targeted grouting valve pipes, the diameters and the wall thicknesses of the first type targeted grouting valve pipe and the second type targeted grouting valve pipes are the same, one end of the first type targeted grouting valve pipe is provided with a guide tip, the other end of the first type targeted grouting valve pipe is provided with an outer/inner screw thread, and the two ends of the second type targeted grouting valve pipe are respectively provided with an inner screw thread and an outer screw thread.

Optionally, an outer sleeve joint is welded at the joint of the two second type targeting grouting valve pipes, namely the two second type targeting grouting valve pipes are connected by adopting outer sleeve full welding or screw thread connection, the length of the outer sleeve joint is not less than 60 cm, and the inner diameter of the outer sleeve joint is not more than 3 mm of the outer diameter of the targeting valve pipe.

Optionally, in step (1), the targeted grouting valve pipe is manufactured by using seamless steel pipe with a diameter of 60 mm, 76 mm, 89 mm or the like. The wall thickness of the targeted grouting valve pipe can be set to be 2-10 mm, such as 3-8 mm.

Optionally, in step (2), the drilling mode is set to high-pressure air drilling, water drilling or mud wall protection.

Preferably, in the step (2), the stability of the drilling machine is good, and the drilling angle meets the design requirement.

Optionally, in the step (3), the jacket material is composed of the following raw materials in parts by weight: 100 parts of water, 100-200 parts of cement and 100-300 parts of bentonite.

Alternatively, in step (4), if single-slurry is used for grouting, one grouting core pipe is provided, and if double-slurry is used for grouting, two grouting core pipes are provided, and the diameter of each grouting core pipe is set to be 15 mm or 20 mm.

Alternatively, when grouting, double-liquid grouting is adopted, and the grouting core pipe is connected with a double-liquid grouting pump through a high-pressure grouting hose.

Optionally, in step (4), the grouting liquid is a sulphoaluminate cement single-liquid slurry, a modified common cement single-liquid slurry or a cement-water glass double-liquid slurry.

Preferably, in the step (4), the grouting liquid has the characteristics of quick setting and early strength, the initial setting time of the single-liquid slurry is 25-45 min, the final setting time is 30-60 min, and the initial setting time of the double-liquid slurry is 30-300S.

Optionally, in step (4), the segment length of the grouting section is set to 0.75-2 m, and the grouting pressure is set to 1-30 MPa.

Alternatively, in step (5), the pressure pump is depressurized, the inner mixing plunger is retracted, and then the hoisting system is used to lift the inner mixing plunger to the next grouting section by lifting the wire rope.

The invention also provides a surface ultra-deep hole directional controlled-area grouting construction method, which comprises the following construction steps: (1) drilling a slurry overflow hole at the design position of the seamless steel pipe with the corresponding specification, installing a slurry stopping valve sleeve protector, processing a connector and processing into a targeted grouting valve pipe, wherein a guide tip is arranged when a first targeted grouting valve pipe in the grouting hole is installed; (2) leveling a construction site, accurately measuring hole position lofting, adjusting a drilling machine to a design angle after the drilling machine is in place, and drilling to a design depth; (3) hoisting the processed targeted grouting valve pipes and the PE pipe into the drilled holes, firmly connecting each targeted grouting valve pipe until the corresponding design depth, installing a pipe with a grout stopping valve sleeve on the designed targeted grouting section, and installing a light pipe on the non-grouting section; (4) injecting casing materials with certain strength through the PE pipe, and closing a gap between the targeted grouting valve pipe and the wall of the drill hole to prevent slurry from vertically streaming; (5) connecting a pressurizing pipe for a pressurizing pump with the inner mixing grouting plug, and connecting a hoisting steel wire rope with a hoisting system; (6) connecting the grouting core pipe, the inner mixed grouting plug pressing pipe and the lifting steel wire rope; (7) after installing a double-core pipe, a pressing pipe with an inner mixed grouting plug and a lifting steel wire rope in the targeted grouting valve pipe, installing the double-core pipe, the pressing pipe with the inner mixed grouting plug and the lifting steel wire rope to the depth of pre-grouting; (8) after the casing materials are solidified, connecting a grouting pipeline, and implementing retreating type sectional grouting through an internal mixed grouting plug; (9) different types of slurry can be injected into different sections according to different geological conditions, the slurry with quick setting, early strength and controllable gel time can be selected, and repeated grouting in the same section is realized; (10) and after the first section of grouting is finished, pulling the inner mixed grouting plug to the next grouting section till all grouting sections of the main hole are finished.

The invention has the beneficial effects that: (1) the problems of excavation and support of the unfavorable geological section do not need to be waited, and then treatment measures are taken, so that the construction safety risk and shutdown risk caused by unfavorable geology are avoided; (2) the advanced pre-reinforcement process of the earth surface ultra-deep hole directional control grouting and the in-tunnel excavation and support construction process are not crossed, and parallel operation can be realized; (3) the large-scale construction is realized, the unfavorable geological section is quickly passed, and the construction period can be effectively shortened; (4) the reinforcing effect is guaranteed, and construction safety and structure safety can be guaranteed.

Drawings

Fig. 1A and 1B show a process schematic diagram of step (1) of the earth surface ultra-deep hole directional controlled-area grouting construction method.

Fig. 2A and 2B show a process schematic diagram of step (2) of the earth surface ultra-deep hole directional controlled-area grouting construction method.

Fig. 3A and 3B show a process schematic diagram of step (3) of the earth surface ultra-deep hole directional controlled-area grouting construction method of the invention.

Fig. 4 shows a process schematic diagram of step (4) of the earth surface ultra-deep hole directional controlled-area grouting construction method.

Detailed Description

The method for directional controlled grouting construction of the surface ultra-deep hole is described in detail with reference to the accompanying drawings.

First, a target grouting valve pipe is manufactured in step 1. According to the design, the length of the steel pipe is cut, a slurry overflow hole 2 is drilled in the steel pipe 1A or 1B, then a slurry stop valve sleeve 3 is installed, and a connecting sleeve member, namely an outer sleeve joint (not shown) is machined. The targeted grouting valve pipe comprises a first type targeted grouting valve pipe shown in figure 1A and a second type targeted grouting valve pipe shown in figure 1B, the diameters and the wall thicknesses of the first type targeted grouting valve pipe and the second type targeted grouting valve pipe are the same, one end of the first type targeted grouting valve pipe is provided with a guide tip, the other end of the first type targeted grouting valve pipe is provided with an outer screw thread 4, and two ends of the second type targeted grouting valve pipe are respectively provided with an outer screw thread 4 and an inner screw thread 5.

In the non-limiting embodiment, the end of the first type targeted grouting valve pipe is not limited by the inner and outer threads, and the end is unified with the thread model of the second type targeted grouting valve pipe, and in the step, the processing sequence of thread processing, drilling of the slurry overflow hole and the processing sequence of the slurry stop valve sleeve can be selected automatically, so that the manufacturing efficiency of the targeted grouting valve pipe can be improved.

In the non-limiting embodiment, an outer sleeve joint is welded at the joint of the two second type targeting grouting valve pipes, namely the two second type targeting grouting valve pipes are connected by adopting outer sleeve full welding or screw thread connection, the length of the outer sleeve joint is not less than 60 cm, and the inner diameter of the outer sleeve joint is not more than 3 mm of the outer diameter of the targeting valve pipe. The targeted grouting valve pipe is made of seamless steel pipes with the diameter of 60 mm, 76 mm, 89 mm or the like.

Next, in step 2, as shown in fig. 2A, the construction site is leveled, the boundary of the reinforcement range is calibrated, the measurement and placement are performed according to the position of the drilling hole site 6 of the designed targeted grouting valve pipe, the hole site center and the cross line are marked with paint, and the pile number is marked according to the design. Then, as shown in fig. 2B, a crawler-type drilling machine 7 located on the ground surface F is adopted, hole location parameters are adjusted at the hole locations of the measurement marks, a drill rod 8 is adjusted according to the angle of the design requirement, drilling is carried out by using a drill bit 9 corresponding to the diameter of the targeted grouting valve pipe, inclination measurement is carried out according to the requirement at the beginning stage of drilling construction, the deviation of the drilling angle is ensured to meet the design requirement, then the long drill rod 8 is connected to drill to the design depth, then hole washing or hole cleaning is carried out, the installation depth of the targeted grouting valve pipe is ensured to meet the design requirement, the drill rod 8 is detached after the hole washing or hole cleaning is completed, and the drilling of the grouting hole 10 is completed.

Then, in step 3, as shown in fig. 3A, first, the target grouting valve pipe 1 is hoisted into the hole together with the PE pipe 13 with the aid of the power head 12 using the hoist rope 11 with the drilling machine 7, and connected to the bottom of the hole one by one. Next, as shown in fig. 3B, a jacket material 14 is injected into the grouting hole 10 through the PE pipe 13, thereby closing a gap between the targeted grouting valve pipe 1 and the wall of the grouting hole 10. In the process of pouring the shell material, the top end of the PE pipe 13 is provided with a ball valve 15.

Next, in step 4, the inner mixing plunger 16 is connected to the pressure pump 18 through the pressuring pipe 17, so that the inner mixing plunger 16 is lifted up by the pressure pump 18, and at the same time, the inner mixing plunger 16 is connected to the hoisting system 20 through the hoisting rope 19, so that the inner mixing plunger 16 is hoisted by the hoisting system 21. In this non-limiting embodiment, two grouted core pipes 21 are connected with the inner mixed grouting plug 16, placed into the targeted grouting valve pipe 1, and the grouted core pipes 21 are lengthened section by section during the lowering process until the bottom of the hole.

After the casing material 14 is solidified, the grouting core pipe 21 is sequentially connected with a high-pressure grouting hose 22, a double-liquid grouting pump 23, a slurry feeding pipe 24, a liquid A stirring barrel 25A and a liquid B stirring barrel 25B, the internal mixing grouting plug 16 is expanded by a pressure pump 18 through a pressure pipe 17 to complete targeted grouting Z of the section, and then section-by-section retreating type sectional grouting is started.

In this non-limiting embodiment, in this step, according to different geological conditions, suitable slurry is injected into different geological sections, or different slurry can be injected into the same section.

Finally, in step 5, after the first section of grouting is completed, the pressure pump 18 releases the pressure, the inner mixed grouting plug 16 contracts, and then the hoisting system 20 is used for hoisting the inner mixed grouting plug 16 to the next grouting section through the hoisting steel rope 19, and the steps are sequentially carried out until all grouting sections of the hole are completed.

Therefore, the method for directional controlled-area grouting construction of the surface ultra-deep hole is suitable for reinforcing and improving the unfavorable geology in front of the tunnel face under the condition of buried deep buried and buried deep, and before the tunnel face is not excavated to the section of the pre-grouting mileage, so that the safety and the structural stability of construction in the tunnel are ensured, the parallel operation of advanced pre-grouting reinforcement of the surface and excavation supporting construction in the tunnel is realized, the interference is avoided, the excavation footage efficiency is greatly improved, and the construction period is shortened.

The application of the construction method of the present invention to engineering is described below with reference to examples.

The Yinxi high-speed railway crosses the largest loess plateau in the world from south to north, namely the Dong plateau, the hills, the high tablelands and the gullies vertically and horizontally, and the yellow brown wrinkles, which are one of the main areas for the distribution of the collapsible loess in China, underground water submerges runoff, is widely distributed in the middle and updated viscous loess stratum by pore submergence, tunnel engineering crosses the underground water level line and the soft plastic loess interlayer for a long time when the tunnel engineering passes through the loess plateau in shallow burial, the problems of softening and deformation of the seepage water of the surrounding rock, sudden collapse, surface subsidence, underground water loss and the like are easily caused, and the difficulty brought to engineering construction and the rare challenge of the world are brought.

The buried depth of the garret tunnel entrance area and the inclined shaft area tunnel on the Yinxi railway is 60-97 m, the surrounding rock of the tunnel is ancient loess of the third system, the tunnel body penetrates through the soft plastic loess section, the highest water content of the stratum is up to 33%, the stability of the surrounding rock is extremely poor, multiple collapse and deformation occur, the construction risk is extremely high, and the construction method is called as 'excavation in rain, support in mud' and 'tunneling in mud' in the industry.

After the earth surface ultra-deep hole directional controlled area grouting construction method is adopted, the water content of surrounding rock is reduced from 31% to 20%, the tunnel face grout pulse is obvious, the stratum is stable, and the excavation effect is good; the maximum values of tunnel surrounding rock settlement and horizontal convergence deformation are respectively reduced by about 60% and 32%, the unconfined compressive strength of coring after reinforcement is as high as more than 0.7Mpa, the impermeability and the bearing capacity of a soil body are both remarkably improved, and the plasticity state of the soil body is effectively improved, so that the invention of the surface ultra-deep hole directional controlled area grouting construction method is successful, the structural deformation is effectively controlled, the construction safety is ensured, and the tunnel excavation progress exceeds 70 m/month which is twice that before measures are not taken.

Although preferred embodiments of the present invention have been described in detail herein, it is to be understood that this invention is not limited to the precise construction and steps herein shown and described, and that other modifications and variations may be effected by one skilled in the art without departing from the spirit and scope of the invention.