Method for blocking flowing water through double-liquid water-soluble polyurethane ground grouting

Abstract

The invention discloses a double-liquid water-soluble polyurethane ground grouting flowing water blocking method. The method comprises the steps that A, ground penetrating roadway drilling construction is conducted; b, a double-pipe grouting device is installed; c, pressing water before grouting; step D, preparing a double-liquid water-soluble polyurethane grouting liquid; e, the double-fluid water-soluble polyurethane grouting fluid is mixed through a double-pipe grouting device and then grouted to a target position; and F, water pressing is conducted after grouting. The method is a more efficient, environment-friendly and economical water gushing treatment scheme, the treatment effect of flowing water plugging in the complex underground environment can be effectively enhanced, and therefore construction and operation safety of the deep-buried tunnel is guaranteed.

Description

Technical Field

[0001] The invention relates to the technical field of deep-buried tunnel water gushing control, and more specifically to a method for sealing moving water by double-liquid water-soluble polyurethane ground grouting. Background Art

[0002] In the field of deep-buried tunnel water gushing control technology, water gushing is a common and challenging problem. During the construction or operation of the tunnel, water gushing often occurs due to the influence of various factors such as groundwater pressure, geological conditions, and construction methods. Water gushing not only affects the safety and progress of tunnel construction, but may also have an adverse impact on the surrounding environment. Traditional water gushing control methods include drainage, precipitation, and plugging. Drainage and precipitation methods require large equipment and energy inputs, and may have an impact on groundwater resources. The plugging method usually uses materials such as concrete and cement, but these materials have a long solidification time and are not effective in plugging dynamic water. Patent CN113683369A forms a modified cement slurry as liquid A and polyurethane as liquid B by adding polyacrylamide to water, and uses the characteristics of water-based polyurethane to react with water to form a gel, and mixes liquid A and liquid B and injects them into the target stratum to achieve dynamic water plugging. However, when this method is used for water gushing control in deep-buried tunnels, especially when the dynamic water flow rate is large, the mechanical strength and stability of the formed solid body are difficult to achieve an ideal plugging effect. Summary of the invention

[0003] To this end, the technical problem to be solved by the present invention is to provide a method for sealing moving water by two-liquid water-soluble polyurethane ground grouting, which is easy to operate, safe in process and reliable in effect, so as to solve the problem that the existing sealing materials and sealing methods have poor sealing effect when dealing with the problem of moving water in deep buried tunnels, especially when the moving water flow rate is large, and the mechanical strength and stability of the formed consolidated body are poor.

[0004] The two-liquid water-soluble polyurethane grouting method of the present invention has the advantages of short solidification time, high strength, good anti-seepage performance, etc., and can quickly and effectively block dynamic water, and is a relatively advanced water gushing control method. The two-liquid water-soluble polyurethane ground grouting method for blocking dynamic water proposed in the present invention is a more efficient, environmentally friendly and economical water gushing control solution, which can effectively enhance the control effect of dynamic water blocking in complex underground environments, thereby ensuring the construction and operation safety of deep buried tunnels.

[0005] In order to solve the above technical problems, the present invention provides the following technical solutions:

[0006] A method for sealing moving water by double-liquid water-soluble polyurethane ground grouting comprises the following steps:

[0007] Step A: Ground tunnel drilling construction;

[0008] Step B, installing a double-tube grouting device;

[0009] Step C, pressurizing water before grouting;

[0010] Step D, preparing a two-liquid water-soluble polyurethane grouting liquid;

[0011] Step E, mixing the two-liquid water-soluble polyurethane grouting liquid through a double-tube grouting device and then grouting it to the target position;

[0012] Step F: Pressurize water after grouting.

[0013] The above-mentioned method for sealing moving water by two-liquid water-soluble polyurethane ground grouting, in step D, the two-liquid water-soluble polyurethane grouting liquid is composed of liquid A and liquid B; liquid A is composed of 84 to 94 parts by weight of sodium silicate solution, 5 to 15 parts by weight of polyether polyol composite catalyst (polyether polyol composite catalyst refers to a catalyst that can be used to catalyze the foaming reaction of polyether polyol and polymethylene polyphenyl polyisocyanate, and can be a commercially available polyether polyol composite catalyst) and 0.1 to 1 parts by weight of silicone foam stabilizer; the concentration of the sodium silicate solution is 40 degrees Baume (i.e., the solid content of sodium silicate is 35wt%);

[0014] Liquid B is a polymethylene polyphenyl polyisocyanate solution with a concentration of 20wt% to 35wt%, wherein the isocyanate content of the polymethylene polyphenyl polyisocyanate is greater than or equal to 30%; the solvent of the polymethylene polyphenyl polyisocyanate solution is chlorobenzene, o-dichlorobenzene or toluene.

[0015] In the above-mentioned method of sealing moving water by double-liquid water-soluble polyurethane ground grouting, in step B, the double-tube grouting device includes a first grouting pump, a second grouting pump, a first grouting pipe, a second grouting pipe, a casing, a bottom hole mixer and a fishtail drill bit; the fluid outlet end of the first grouting pump is fluidly connected to the fluid inlet end of the first grouting pipe, and the fluid outlet end of the second grouting pump is fluidly connected to the fluid inlet end of the second grouting pipe; the fluid outlet end of the first grouting pipe and the fluid outlet end of the second grouting pipe are both fluidly connected to the fluid inlet end of the bottom hole mixer; the fluid outlet end of the bottom hole mixer is fluidly connected to the fluid inlet end of the fishtail drill bit; the fluid inlet end of the first grouting pump is fluidly connected to the A liquid stirring barrel, and the fluid inlet end of the second grouting pump is fluidly connected to the B liquid stirring barrel;

[0016] The inner diameter of the first grouting pipe is larger than the outer diameter of the second grouting pipe; the fluid outlet end of the second grouting pipe extends from the fluid inlet end of the first grouting pipe to the fluid outlet end of the first grouting pipe, and the central axes of the first grouting pipe and the second grouting pipe coincide with each other; the inner diameter of the casing is larger than the outer diameter of the first grouting pipe; the fluid outlet end of the first grouting pipe extends from the ground end of the casing to the underground end of the casing, and the central axes of the first grouting pipe and the casing coincide with each other; the first grouting pipe is fixed to the casing by a flange; the casing is fixed in the grouting borehole by solid pipe cement slurry.

[0017] In the above-mentioned method of two-liquid water-soluble polyurethane ground grouting to block moving water, the inner diameter of the first grouting pipe is 1.7 to 2.2 times the inner diameter of the second grouting pipe. When the inner diameters of the first grouting pipe and the second grouting pipe are within the above-mentioned ratio range, the transported liquid A and liquid B can be mixed more evenly in the bottom-hole mixer, and the two grouting liquids react faster and more fully, thereby obtaining a consolidated body with more ideal performance.

[0018] In the above-mentioned method of double-liquid water-soluble polyurethane ground grouting to block moving water, the first grouting pipe is a Φ89 drill tool, and the second grouting pipe is a Φ42 drill tool; since the amount of liquid A used is relatively large relative to the amount of liquid B, the present invention has found in repeated tests that when the Φ89 drill tool and the Φ42 drill tool are used as grouting pipes for liquid A and liquid B respectively, the reaction of liquid A and liquid B after mixing is most sufficient, and basically no waste of materials will be caused; the outer diameter of the casing is 244.5mm and the wall thickness is 8.94mm; the first grouting pump is an F260 grouting pump, and the second grouting pump is an NBB390 grouting pump. Before the installation of the second grouting pipe check valve, the check valve spring needs to be cut off one and a half turns to reduce the problem of excessive pipe resistance caused by the check valve. The pipe resistance of the double pipe (i.e., the first grouting pipe and the second grouting pipe) is controlled at a pump pressure of about 0.3MPa); the adjustable pump volume range of the F260 grouting pump is 0~40m 3 The maximum pump pressure can reach 15MPa, and the pump volume of NBB-390 grouting pump can be adjusted in five gears (1st gear 3.1m 3 / h, 2nd gear 5.4m 3 / h, 3rd gear 9.6m 3 / h, 4th gear 15m 3 / h, 5th gear 23.4m 3 / h), the maximum pump pressure can reach 8MPa.

[0019] In the above-mentioned method for sealing moving water by grouting with two liquids of water-soluble polyurethane, in step E, during grouting, the flow rates of liquid A and liquid B are controlled so that they are mixed in the bottom-hole mixer at a mass ratio of 1: (0.5-1.0). When liquid A and liquid B in the present invention are mixed within the above-mentioned ratio range, they can react sufficiently and quickly to generate a solidified body with a stable structure and relatively ideal mechanical strength, with high solidification efficiency, good grouting and water blocking effect, and the material usage is the most economical, without causing material waste.

[0020] In the above-mentioned method of two-liquid water-soluble polyurethane ground grouting to block moving water, in step E, during grouting, the flow rates of liquid A and liquid B are controlled so that they are mixed in the bottom hole mixer at a mass ratio of 1:1.

[0021] In the above-mentioned method for sealing dynamic water by grouting with two liquids of water-soluble polyurethane on the ground, in step E, during grouting, the flow rates of liquid A and liquid B are both 90 to 190 L / min. When the flow rates of liquid A and liquid B are within this range, the two liquids react fully, and the diffusion range formed when they are transported to the bottom of the hole through the above-mentioned double-tube grouting device can meet the requirements of dynamic water sealing in deep buried tunnels, and has a good dynamic water sealing effect.

[0022] In the above-mentioned method of two-liquid water-soluble polyurethane ground grouting to block moving water, in step E, during grouting, the temperature of the two-liquid water-soluble polyurethane grouting liquid is controlled to be 20-25°C; or during grouting, the viscosity of the two-liquid water-soluble polyurethane grouting liquid is controlled to be 60-80s. The grouting raw materials (two-liquid water-soluble polyurethane grouting liquid) are transported to the insulation room for preheating 2 days in advance, and after the grouting drill is lowered into place and the double-tube grouting device is installed, it is transported to the on-site grouting station after the water pressure test is normal.

[0023] In the above-mentioned method of two-liquid water-soluble polyurethane ground grouting to seal moving water, in step A, the ground construction is accurately drilled to 0.8 to 1.5 m below the bottom plate of the water-gushing tunnel, and the borehole deviation rate is less than or equal to 1‰. The purpose of ground construction through-tunnel drilling is to inject two-liquid water-soluble polyurethane into the moving water area to achieve the purpose of sealing. During the drilling process, it is necessary to select a suitable drilling location, diameter and depth according to the actual situation (including the properties of the two-liquid water-soluble polyurethane, etc.), and use professional drilling equipment for operation. After the drilling is completed, the borehole should be cleaned and inspected to ensure that the drilling quality meets the requirements and provide guarantee for the subsequent grouting and sealing work;

[0024] In step B, before the double-tube drilling, the mixer is checked and cleaned, and the one-way valve is installed; the bottom of the drill tool is connected to the bottom-hole mixer, the lower part of the mixer is connected to the fishtail drill bit, and the bottom of the drill bit extends into the deep buried tunnel; after the double-tube drilling rig and the bottom-hole mixer are lowered, the orifice grouting device is installed, the inner and outer pipe seals must be installed securely, and the sealing ring must be fully coated with butter and squeezed densely; during the grouting process, the drill tool is moved up and down based on the remaining water flow space, and the range of movement is 0.4 to 1.5 m (it can also be determined according to the bottom conditions of each borehole). If the range of movement of the drill tool is too large, it will affect the stability of the accumulation body generated at the bottom, thereby affecting the rapid accumulation of the slurry; the grouting liquid is mixed at the bottom of the hole, and the drilling is not only slurry, but the grouting liquid flows into the tunnel through the fishtail drill bit; compared with other types of drill bits, the fishtail drill bit used in the present invention can make the grouting liquid better form a stable consolidation body at the target position;

[0025] In step C, a water pressure test is performed before grouting using clean water at a temperature of 20 to 25°C. During the water pressure test, the double tubes are first subjected to a water pressure test separately and then to a water pressure test on the double tubes simultaneously. The standard for the water pressure test is that the double tubes are not connected in series at the top of the bottom-hole mixer and the water pressure of a single pipeline meets the pump pressure of 0.25 to 0.35 MPa (preferably 0.3 MPa).

[0026] In step D, personnel are arranged to carry liquid A and liquid B of the two-liquid water-soluble polyurethane grouting liquid that meet the temperature requirements and place them in two grouting stirring barrels (liquid A stirring barrel and liquid B stirring barrel) of the grouting station respectively. When the grouting pump is continuously grouting, materials are continuously taken and added, and the temperature of the two-liquid water-soluble polyurethane grouting liquid is maintained, so as to facilitate the continuous grouting operation of the grouting pump. The technical personnel detect the temperature of the AB two-liquid water-soluble polyurethane grouting liquid in the stirring barrel at any time; during outdoor construction in winter, the grouting stirring barrel is wrapped with a heating belt for continuous heating, and is wrapped with rubber and plastic insulation cotton. Before grouting is implemented, the temperature of the grouting stirring barrel is not lower than the temperature of the AB two-liquid water-soluble polyurethane grouting liquid; the grouting pipeline from the grouting pump to the drilling site is wrapped with a constant temperature heating belt and rubber and plastic insulation cotton, and is maintained by constant temperature heating to ensure that the slurry does not increase in viscosity due to continuous cooling of the grouting pipeline during grouting;

[0027] Before grouting, the technicians measure the temperature of the AB double liquid water-soluble polyurethane grouting liquid after heating in real time. The heating temperature must be controlled above 20°C (preferably 20-25°C). After the technicians determine that the heating of the A liquid and B double liquid water-soluble polyurethane grouting liquid meets the grouting requirements and the viscosity is reduced, they will notify the grouting personnel to carry out the grouting construction;

[0028] In step E, during the double-liquid grouting process, the pump pressure of the outer tube (the first grouting tube) is about 0.3Mpa at 180L / min, and the pump pressure of the inner tube (the second grouting tube) is about 0.2Mpa at 90L / min; during the grouting, the grouting team leader monitors the double-pump grouting pressure in real time. When the single-pump grouting pressure rises to 50% of the rated grouting pressure of the grouting pump, the grouting single pump is immediately stopped and the water is pressurized for 30s (to flush the pipeline and flush the two materials remaining in the pipeline to avoid blocking the pipe and the hole). When the water pressure is reduced to the normal grouting pressure, the normal grouting work is resumed, and it is repeated in sequence;

[0029] In step F, after the grouting is completed, the two pumps are staggered for 30 seconds to perform post-injection water pressure, and after water pressure, the double-tube drilling tool grouting pipeline at the orifice is untied, and the two-way drilling tools are simultaneously lifted up by about 50m, and then the drilling tools are lifted in the order of first lifting the inner tube and then lifting the outer tube;

[0030] In case of a sudden power outage during grouting, grouting should be stopped immediately, the grouting pipe of the outer grouting pump should be immediately placed in the clean water pool, the grouting pipe of the inner grouting pump should continue to be placed in the grouting liquid, and the outer grouting pump should be started immediately, and the inner grouting pump should be started again after a delay of 10 seconds. The outer pipe should be immediately pressurized with water, and the inner pipe should continue to be poured with grouting liquid. After the outer pipe grouting pump has been pressurizing water for 30 seconds, the inner pipe grouting pump should start to pressurize water. After the inner and outer pipe grouting pumps have completed water pressurization, the grouting station should immediately shut down the grouting pump, start the air pump to clean the grouting pipeline, and at the same time, start the drilling rig to pull out the dual-path grouting drill tool.

[0031] The technical solution of the present invention achieves the following beneficial technical effects:

[0032] 1. When the liquid A and liquid B of the two-liquid water-soluble polyurethane grouting liquid are heated to 20-25°C, the viscosity can be reduced to meet the self-priming grouting requirements of the on-site grouting pump, and the foaming time after the two liquids are mixed can be accelerated. The two-liquid water-soluble polyurethane material in the present invention has excellent chemical stability, mechanical strength and water resistance, can be quickly solidified in a dynamic water environment with a large dynamic water flow rate, and form a water-impermeable solid body, so as to achieve the purpose of blocking dynamic water, while ensuring the deep buried tunnel treatment effect, reducing the construction cost of its blocking.

[0033] 2. The two-liquid water-soluble polyurethane grouting material of the present invention has low viscosity after being mixed with water and has good groutability. Its solid body is non-toxic, non-polluting and harmless to the human body when immersed in water, and has excellent corrosion resistance and water erosion resistance, and can maintain the waterproof and anti-seepage capabilities of the structure for a long time.

[0034] 3. The double-liquid water-soluble polyurethane grouting liquid ground grouting and water blocking method of the present invention provides a new solution for deep-buried tunnel water gushing control through innovative materials and processes. The method not only broadens the selection range of control materials, but also optimizes the construction process, significantly improving the control efficiency and success rate. The method of the present invention has economical practicality, efficient construction process, simple operation steps and low economic cost.

[0035] 4. The double-liquid grouting device of the present invention inserts the second grouting pipe used for grouting of liquid B in the present invention into the first grouting pipe used for grouting of liquid A in the present invention, and installs a bottom hole mixer at the bottom of the double pipes. By selecting drilling tools with specific inner diameters as the first grouting pipe and the second grouting pipe, liquid A and liquid B in the present invention can be quickly and fully mixed in the bottom hole mixer, which is conducive to rapid reaction to generate a consolidated body with ideal mechanical strength. At the same time, by controlling the grouting flow rates of liquid A and liquid B, the grouting liquid has a suitable diffusion range, so that a consolidated body with good stability can be quickly formed at the dynamic water position of a deep-buried tunnel with a large dynamic water flow rate. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] Figure 1 Schematic diagram of a method for ground grouting and plugging dynamic water using a double-liquid water-soluble polyurethane grouting liquid in an embodiment of the present invention;

[0037] Figure 2 Operation flow chart of the method for ground grouting and plugging dynamic water with double liquid water-soluble polyurethane grouting liquid in an embodiment of the present invention;

[0038] Figure 3 A schematic diagram of a method for ground grouting and plugging dynamic water using a double-liquid water-soluble polyurethane grouting liquid in another embodiment of the present invention.

[0039] The reference numerals are as follows: 1-first grouting pump; 2-second grouting pump; 3-first grouting pipe; 4-second grouting pipe; 5-fastening bolts; 6-upper and lower flanges; 7-A liquid mixing barrel; 8-B liquid mixing barrel; 9-solid pipe cement slurry; 10-casing; 11-bottom hole mixer; 12-fishtail drill bit; 13-consolidation body; 14-water gushing direction. DETAILED DESCRIPTION

[0040] The method of the present invention of double liquid water-soluble polyurethane ground grouting to block dynamic water was carried out in an engineering test, and its operation process is shown in Figure 2 , specifically including the following steps:

[0041] Step A, ground tunnel drilling construction; ground tunnel drilling is to inject two-liquid water-soluble polyurethane into the dynamic water area to achieve the purpose of plugging. During the drilling process, it is necessary to select the appropriate drilling position, diameter and depth according to the actual situation, and use professional drilling equipment for operation. After the drilling is completed, the borehole should be cleaned and inspected to ensure that the drilling quality meets the requirements and provide guarantee for the subsequent grouting and plugging work. The ground construction is accurately drilled to 1m below the bottom plate of the water-gushing tunnel, and the drilling deviation rate is less than or equal to 1‰.

[0042] Step B, installing a double-tube grouting device, lowering a double-tube drilling tool and a bottom-hole mixer;

[0043] The double-tube grouting device in this embodiment is as follows Figure 1 As shown, it includes a first grouting pump 1, a second grouting pump 2, a first grouting pipe 3, a second grouting pipe 4, a casing 10, a bottom hole mixer 11 and a fishtail drill bit 12; the fluid outlet end of the first grouting pump 1 is fluidly connected to the fluid inlet end of the first grouting pipe 3, and the fluid outlet end of the second grouting pump 2 is fluidly connected to the fluid inlet end of the second grouting pipe 4; the fluid outlet end of the first grouting pipe 3 and the fluid outlet end of the second grouting pipe 4 are both fluidly connected to the fluid inlet end of the bottom hole mixer 11; the fluid outlet end of the bottom hole mixer 11 is fluidly connected to the fluid inlet end of the fishtail drill bit 12; the fluid inlet end of the first grouting pump 1 is fluidly connected to the A liquid stirring barrel 7, and the fluid inlet end of the second grouting pump 2 is fluidly connected to the B liquid stirring barrel 8;

[0044] The inner diameter of the first grouting pipe 3 is larger than the outer diameter of the second grouting pipe 4; the fluid outlet end of the second grouting pipe 4 extends from the fluid inlet end of the first grouting pipe 3 to the fluid outlet end of the first grouting pipe 3, and the central axes of the first grouting pipe 3 and the second grouting pipe 4 coincide with each other; the inner diameter of the casing 10 is larger than the outer diameter of the first grouting pipe 3; the fluid outlet end of the first grouting pipe 3 extends from the ground end of the casing 10 to the underground end of the casing 10, and the central axes of the first grouting pipe 3 and the casing 10 coincide with each other; the first grouting pipe 3 is fixed to the casing 10 by a flange 6; the casing 10 is fixed in the grouting borehole by fixed pipe cement slurry 9.

[0045] The first grouting pipe 3 is a Φ89 drilling tool, and the second grouting pipe 4 is a Φ42 drilling tool; the outer diameter of the casing 10 is 244.5mm and the wall thickness is 8.94mm; the first grouting pump 1 is an F260 grouting pump, and the second grouting pump 2 is an NBB390 grouting pump; the spring of the check valve of the second grouting pipe needs to be cut off one and a half turns before the check valve is installed to reduce the problem of excessive pipe resistance caused by the check valve. The pipe resistance of the double pipe (i.e. the first grouting pipe and the second grouting pipe) is controlled at a pump pressure of about 0.3MPa); the pump volume of the F260 grouting pump can be adjusted in the range of 0 to 40m3 The maximum pump pressure can reach 15MPa, and the pump volume of NBB-390 grouting pump can be adjusted in five gears (1st gear 3.1m 3 / h, 2nd gear 5.4m 3 / h, 3rd gear 9.6m 3 / h, 4th gear 15m 3 / h, 5th gear 23.4m 3 / h), the maximum pump pressure can reach 8MPa;

[0046] Before lowering the double-tube drilling, check and clean the mixer and install the one-way valve; the bottom of the drill bit is connected to the bottom-hole mixer, the lower part of the mixer is connected to the fishtail drill bit, and the bottom of the drill bit extends into the deep-buried tunnel; the Φ89 drill bit is used for grouting with liquid A, and the Φ42 drill bit is used for grouting with liquid B; after the double-tube drilling rig and the bottom-hole mixer are lowered, the hole grouting device is installed, the inner and outer pipe seals must be installed securely, and the sealing ring must be fully coated with butter and squeezed tightly;

[0047] During the grouting process, the drill tool is moved up and down based on the remaining water space, with a range of 0.4 to 1.5 m (it can also be determined according to the bottom conditions of each borehole). The grouting liquid is mixed at the bottom of the hole, and the grouting liquid flows into the tunnel through the fishtail drill bit. Before drilling, the mixer of the double pipe (the first grouting pipe and the second grouting pipe) is checked and cleaned, and the one-way valve is installed. During the double-liquid grouting process, the pump pressure of the outer pipe is about 0.3Mpa at 180L / min, and the pump pressure of the inner pipe is about 0.2Mpa at 90L / min.

[0048] Step C, water pressure before grouting; before grouting, water pressure test is performed using clean water with a temperature of 20-25°C. During the water pressure test, the double tubes are first subjected to water pressure test separately and then to water pressure test on the double tubes simultaneously; the standard of the water pressure test is that the double tubes are not connected in series at the top of the mixer at the bottom of the hole and the water pressure of the single pipeline meets the pump pressure of 0.3MPa.

[0049] Step D, preparing a two-liquid water-soluble polyurethane grouting liquid; the two-liquid water-soluble polyurethane grouting liquid consists of liquid A and liquid B; liquid A consists of 45kg of sodium silicate solution, 4.75kg of polyether polyol composite catalyst and 0.25kg of organosilicon foam stabilizer; the concentration of the sodium silicate solution is 40 degrees Baume, that is, the content of sodium silicate is 35wt%; liquid B is 50kg of 35% concentration of polymethylene polyphenyl polyisocyanate solution, the solvent is toluene, wherein the isocyanate content of the polymethylene polyphenyl polyisocyanate is 40%.

[0050] Liquid A and liquid B of the two-liquid water-soluble polyurethane grouting liquid that meet the temperature requirements are placed in two grouting stirring barrels (liquid A stirring barrel and liquid B stirring barrel) of the grouting station respectively. When the grouting pump is continuously grouting, materials are continuously taken and added, and the temperature of the two-liquid water-soluble polyurethane grouting liquid is maintained, so as to facilitate the continuous grouting operation of the grouting pump. The technicians detect the temperature of the AB two-liquid water-soluble polyurethane grouting liquid in the stirring barrel at any time; since the present embodiment is constructed outdoors in winter, the grouting stirring barrel is wrapped with a heating belt for continuous heating, and is wrapped with rubber and plastic insulation cotton. Before the grouting is implemented, the temperature of the grouting stirring barrel is higher than or equal to the temperature of the two-liquid water-soluble polyurethane grouting liquid; the grouting pipeline from the grouting pump to the drilling site is wrapped with a constant temperature heating belt and rubber and plastic insulation cotton, and is maintained by constant temperature heating;

[0051] The grouting raw materials (two-liquid water-soluble polyurethane grouting liquid) are transported to the insulation room for preheating 2 days in advance. After the grouting drill is lowered into place and the double-tube grouting device is installed and the water pressure test is normal, they are transported to the on-site grouting station; before the grouting is implemented, the technicians measure the temperature of the AB two-liquid water-soluble polyurethane grouting liquid after heating in real time. The heating temperature must be controlled above 20°C (preferably 20-25°C). After the technicians determine that the heating of the A liquid and B two-liquid water-soluble polyurethane grouting liquid meets the grouting requirements and the viscosity is reduced, they notify the grouting personnel to carry out the grouting construction;

[0052] Step E: Mix the two-liquid water-soluble polyurethane grouting liquid through a double-tube grouting device and then grout to the target position; during grouting, control the flow rate of liquid A and liquid B so that they are mixed in the bottom hole mixer at a mass ratio of 1:1. During grouting, control the temperature of the two-liquid water-soluble polyurethane grouting liquid to 20-25°C;

[0053] In this embodiment, the flow rates of liquid A and liquid B are both 160L / min; during grouting, the dual-pump grouting pressure is monitored in real time. When the single-pump grouting pressure rises to 50% of the rated grouting pressure of the grouting pump, the grouting single pump is immediately stopped and the water is pressurized for 30s. When the water pressure is reduced to the normal grouting pressure, the normal grouting work is resumed, and the process is repeated in sequence;

[0054] Step F, water pressure after grouting. After grouting, the two pumps are staggered for 30 seconds to perform water pressure after grouting. After water pressure, the double-tube drilling tool grouting pipeline at the orifice is untied, and the two-way drilling tools are lifted up about 50m at the same time, and then the inner tube is lifted first and then the outer tube is lifted to lift the drilling tools;

[0055] In case of a sudden power outage during grouting, grouting should be stopped immediately, the grouting pipe of the outer grouting pump should be immediately placed in the clean water pool, the grouting pipe of the inner grouting pump should continue to be placed in the grouting liquid, and the outer grouting pump should be started immediately, and the inner grouting pump should be started again after a delay of 10 seconds. The outer pipe should be immediately pressurized with water, and the inner pipe should continue to be poured with grouting liquid. After the outer pipe grouting pump has been pressurizing water for 30 seconds, the inner pipe grouting pump should start to pressurize water. After the inner and outer pipe grouting pumps have completed water pressurization, the grouting station should immediately shut down the grouting pump, start the air pump to clean the grouting pipeline, and at the same time, start the drilling rig to pull out the dual-path grouting drill tool.

[0056] The dynamic water flow rate of the deep buried tunnel in this embodiment is 1000m 3 / h. The above construction method can achieve rapid blocking of dynamic water within 72 hours, and the formed stone consolidation body has good mechanical strength (24h compressive strength 38MPa, greater than 30MPa, shear strength 13MPa, greater than 10MPa, tensile strength 7MPa, greater than 5MPa), and the blocking effect is sustained and stable.

[0057] In other embodiments, the following may also be used: Figure 3 The double-tube grouting device shown in the figure is used to perform the double-liquid water-soluble polyurethane ground grouting to block the dynamic water in the above embodiment, but its blocking effect is relatively poor compared with the above embodiment (dynamic water flow rate 900m 3 / h, plugging was achieved in 82H, and the formed consolidation body had a compressive strength of 25MPa, a shear strength of 8MPa, and a tensile strength of 4.5MPa at 24h. This may be because when the first grouting pipe and the second grouting pipe were filled according to Figure 3 When installed in this manner, the mixing efficiency and mixing effect of liquid A and liquid B are not as good as the case in which the second grouting pipe is sleeved inside the first grouting pipe in the above embodiment, thereby affecting the reaction rate and reaction sufficiency of liquid A and liquid B.

[0058] Obviously, the above embodiments are merely examples for the purpose of clear explanation, and are not intended to limit the implementation methods. For those skilled in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to list all the implementation methods here. The obvious changes or modifications derived therefrom are still within the scope of protection of the claims of this patent application.

Claims

1. A method for sealing moving water by two-liquid water-soluble polyurethane ground grouting, characterized in that: The steps include: Step A: Ground tunnel drilling construction; Step B, installing a double-tube grouting device; Step C, pressurizing water before grouting; Step D, preparing a two-liquid water-soluble polyurethane grouting liquid; Step E, mixing the two-liquid water-soluble polyurethane grouting liquid through a double-tube grouting device and then grouting it to the target position; Step F: Pressurize water after grouting.

2. The method for sealing dynamic water by two-liquid water-soluble polyurethane ground grouting according to claim 1 is characterized in that: In step D, the two-liquid water-soluble polyurethane grouting liquid is composed of liquid A and liquid B; liquid A is composed of 84 to 94 parts by weight of sodium silicate solution, 5 to 15 parts by weight of polyether polyol composite catalyst and 0.1 to 1 part by weight of organosilicon foam stabilizer; the concentration of the sodium silicate solution is 40 degrees Baume; Liquid B is a polymethylene polyphenyl polyisocyanate solution with a concentration of 20 wt % to 35 wt %, and the isocyanate content of the polymethylene polyphenyl polyisocyanate is greater than or equal to 30%.

3. The method for sealing dynamic water by two-liquid water-soluble polyurethane ground grouting according to claim 2 is characterized in that: In step B, the double-tube grouting device comprises a first grouting pump (1), a second grouting pump (2), a first grouting pipe (3), a second grouting pipe (4), a casing (10), a bottom hole mixer (11) and a fishtail drill bit (12); the fluid outlet end of the first grouting pump (1) is fluidly connected to the fluid inlet end of the first grouting pipe (3), and the fluid outlet end of the second grouting pump (2) is fluidly connected to the fluid inlet end of the second grouting pipe (4); the fluid outlet end of the first grouting pipe (3) and the fluid outlet end of the second grouting pipe (4) are both fluidly connected to the fluid inlet end of the bottom hole mixer (11); the fluid outlet end of the bottom hole mixer (11) is fluidly connected to the fluid inlet end of the fishtail drill bit (12); the fluid inlet end of the first grouting pump (1) is fluidly connected to the A liquid stirring barrel (7), and the fluid inlet end of the second grouting pump (2) is fluidly connected to the B liquid stirring barrel (8); The inner diameter of the first grouting pipe (3) is greater than the outer diameter of the second grouting pipe (4); the fluid outlet end of the second grouting pipe (4) extends from the fluid inlet end of the first grouting pipe (3) to the fluid outlet end of the first grouting pipe (3), and the central axes of the first grouting pipe (3) and the second grouting pipe (4) coincide with each other; the inner diameter of the casing (10) is greater than the outer diameter of the first grouting pipe (3); the fluid outlet end of the first grouting pipe (3) extends from the ground end of the casing (10) to the underground end of the casing (10), and the central axes of the first grouting pipe (3) and the casing (10) coincide with each other; the first grouting pipe (3) is fixed to the casing (10) by a flange (6); and the casing (10) is fixed in the grouting borehole by pipe-fixing cement slurry (9).

4. The method for sealing dynamic water by two-liquid water-soluble polyurethane ground grouting according to claim 3 is characterized in that: The inner diameter of the first grouting pipe (3) is 1.7 to 2.2 times the inner diameter of the second grouting pipe (4).

5. The method for sealing dynamic water by two-liquid water-soluble polyurethane ground grouting according to claim 4 is characterized in that: The first grouting pipe (3) is a Φ89 drilling tool, and the second grouting pipe (4) is a Φ42 drilling tool; the outer diameter of the casing (10) is 244.5 mm, and the wall thickness is 8.94 mm; the first grouting pump (1) is an F260 grouting pump, and the second grouting pump (2) is an NBB390 grouting pump.

6. The method for sealing dynamic water by two-liquid water-soluble polyurethane ground grouting according to claim 2, characterized in that: In step E, during grouting, the flow rates of liquid A and liquid B are controlled so that the mass ratio of the two is 1:(0.5-1.0).

7. The method for sealing moving water by two-liquid water-soluble polyurethane ground grouting according to claim 6, characterized in that: In step E, during grouting, the flow rates of liquid A and liquid B are controlled so that the mass ratio of the two is 1:

1.

8. The method for sealing dynamic water by two-liquid water-soluble polyurethane ground grouting according to claim 7, characterized in that: In step E, during grouting, the flow rates of liquid A and liquid B are both 90 to 190 L / min.

9. The method for sealing moving water by two-liquid water-soluble polyurethane ground grouting according to claim 2, characterized in that: In step E, during grouting, the temperature of the two-liquid water-soluble polyurethane grouting liquid is controlled to be 20-25° C.; or during grouting, the viscosity of the two-liquid water-soluble polyurethane grouting liquid is controlled to be 60-80s.

10. The method for sealing moving water by two-liquid water-soluble polyurethane ground grouting according to any one of claims 3 to 9, characterized in that: In step A, accurate drilling is performed on the ground to a position 0.8 to 1.5 m below the bottom plate of the water-gushing tunnel, and the borehole deviation rate is less than or equal to 1‰; In step B, during the grouting process, the drill tool is moved up and down based on the remaining water-passing space, with a range of 0.4 to 1.5 m, and the drilling hole is not grouted; In step C, a water pressure test is performed before grouting using clean water at a temperature of 20 to 25° C. During the water pressure test, the first grouting pipe (3) and the second grouting pipe (4) are firstly subjected to a water pressure test respectively, and then the first grouting pipe (3) and the second grouting pipe (4) are subjected to a water pressure test simultaneously; the standard of the water pressure test is that the first grouting pipe (3) and the second grouting pipe (4) are not connected in series at the top of the bottom hole mixer (11) and the water pressure of the single-channel pipeline meets the pump pressure of 0.25 to 0.35 MPa; In step D, during outdoor construction in winter, the grouting mixing barrel is wrapped with a heating tape for continuous heating, and is wrapped with rubber and plastic insulation cotton. Before grouting is implemented, the temperature of the grouting mixing barrel is higher than or equal to the temperature of the two-liquid water-soluble polyurethane grouting liquid; the grouting pipeline from the grouting pump to the drilling site is wrapped with a constant temperature heating tape and rubber and plastic insulation cotton, and is maintained by constant temperature heating; In step E, during the dual-liquid grouting process, when the flow rate of the first grouting pipe (3) is 180L / min, the pump pressure is 0.3Mpa, and when the flow rate of the second grouting pipe (4) is 90L / min, the pump pressure is 0.2Mpa; during the grouting process, the dual-pump grouting pressure is monitored in real time, and when the single-pump grouting pressure rises to 50% of the rated grouting pressure of the grouting pump, the grouting single pump is immediately stopped and the water pressure is staggered for 30s, and when the water pressure drops to the normal grouting pressure, the normal grouting work is resumed, and the process is repeated in sequence; In step F, after the grouting is completed, the two pumps are staggered for 30 seconds to perform post-injection water pressure, and after water pressure, the double-tube drilling tool grouting pipeline at the orifice is untied, and the two-way drilling tools are simultaneously lifted up by about 50m, and then the drilling tools are lifted in the order of first lifting the inner tube and then lifting the outer tube; When a power outage occurs during grouting, grouting is stopped immediately, the suction pipe of the first grouting pump (1) is immediately placed in the clean water tank, the suction pipe of the second grouting pump (2) continues to be placed in the grouting liquid B, and the first grouting pump (1) is immediately started, and the second grouting pump (2) is started again after a delay of 10 seconds. The first grouting pipe (3) is immediately pressurized with water, and the second grouting pipe (4) immediately continues to be filled with grouting liquid B. When the first grouting pump (1) pressurizes water for 30 seconds, the second grouting pump (2) presses water. After the first grouting pump (1) and the second grouting pump (2) have completed pressurizing water, the grouting station immediately closes the two grouting pumps, and starts the air pump to clean the grouting pipeline. At the same time, the drilling rig is started to pull out the first grouting pipe (3) and the second grouting pipe (4).

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