Complete-set rotary jet grouting construction method under high confined water condition
By using combined technologies such as rotary spray equipment and solenoid valves to seal the slurry return channel of rotary spray piles under high pressure water conditions, the slurry return problem is solved, the impact of pressure water on construction is reduced, and the construction quality and efficiency are improved.
Patent Information
- Application Number
- CN202411367463.1
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-09-29
- Publication Date
- 2024-12-20
AI Technical Summary
Under high pressure water conditions, the problem of slurry return during construction of rotary spray piles is serious. The curing agent sprayed into the soil fails to solidify and is brought out of the surface, which affects the construction quality, and the pressure of the pressure water is too high, resulting in a return. Severe sludge.
Using a combination of rotary spray equipment and steel sleeves, solenoid valves, pressure gauges, and solenoid switches, the resumption channel of rotary spray piles is sealed at the construction site below the water level line, and the solenoid valve is controlled by using the pressure threshold monitored by the pressure gauge. The opening and closing of the slurry is ensured that the sealing pressure is the same as the water level difference. When the pressure reaches the set value, the slurry return channel is smooth, and the slurry is blocked when the set value is not reached, realizing the pressure construction of the pile body.
The impact of pressure-bearing water on the rotary spray piles is minimized, the construction quality and efficiency are improved, the slurry is prevented from being brought out of the surface, and the stability and construction safety of the pile body are ensured.
Smart Images
Figure CN119163020A_ABST
Abstract
Description
Technical Field
[0001] The invention belongs to the technical field of rotary jet grouting pile construction, and in particular relates to a complete rotary jet grouting construction method under high-pressure water conditions. Background Art
[0002] High-pressure rotary jet construction technology uses a rotating nozzle to spray high-speed fluid while cutting the soil and mixing cement slurry with the chopped soil. After chemical reaction, a solid reinforced soil column is formed with a strength of more than several megapascals. The method was invented by Dr. Nakanishi Shigeru of NIT in Japan. It was originally a simple single-tube method (also known as the CCP method), and then the double-tube method and triple-tube method were developed. The single-tube method only sprays cement slurry; the double-tube method uses compressed air to coaxially wrap high-pressure cement slurry to cut the soil and mix the two, so that the diameter of the reinforced body is greatly increased compared with the single-tube method; the triple-tube method uses compressed air to coaxially wrap high-pressure water flow to first cut the soil, forming a larger diameter of the broken soil gap, and then injects cement slurry with a mud pump to fill and mix, so that the diameter of the reinforced body is greatly increased compared with the first two methods. Since the successful development of high-pressure rotary jet construction technology in my country in the late 1970s, this method has been widely used in many engineering fields in China, such as water conservancy project anti-seepage walls, urban underground projects, slope stability, docks, bridge foundations, etc.
[0003] However, when constructing in a confined water area, the waterproof layer above the confined water has a certain thickness. Especially when constructing in foundation pits and other projects below the water level, the problem of slurry return is serious. The curing agent sprayed into the soil is carried out of the ground surface by the slurry return before solidification, which seriously affects the construction quality. In addition, the confined water pressure is too large, and the slurry return is serious. Based on this, the present invention proposes a complete set of rotary grouting construction methods under high confined water conditions. Summary of the invention
[0004] In view of the above technical problems existing in the prior art, the present invention proposes a complete set of rotary grouting construction methods under high pressure water conditions, which overcomes the shortcomings of the prior art. The return grouting channel of the rotary grouting pile is blocked at the construction site below the water level, and the blocking pressure is the same as the head pressure formed by the water level difference. When the blocking pressure reaches the set value, the return grouting channel is smooth. When the blocking pressure does not reach the set value, the return grouting channel is blocked by the electromagnetic valve, and the slurry cannot be discharged smoothly. In this way, the pile body is constructed under pressure, which minimizes the impact of the pressure water on the rotary grouting pile.
[0005] In order to achieve the above object, the present invention adopts the following technical solution: A complete set of rotary grouting construction method under high pressure water conditions, characterized in that: rotary grouting equipment is used for construction, including a rotary grouting drill rod and a rotary grouting drill, and also including a steel sleeve, a solenoid valve, a pressure gauge, and an electromagnetic switch, wherein the steel sleeve is inserted into the designed hole position, and the end of the steel sleeve above the ground is a semi-closed end, and a lateral flow pipe is opened in the part of the steel sleeve above the ground, and a solenoid valve and a pressure gauge are arranged on the lateral flow pipe, and the solenoid valve and the pressure gauge are transmitted through signals, and the pressure threshold monitored by the pressure gauge controls the opening and closing of the solenoid valve, and the electromagnetic switch is arranged inside the steel sleeve near the side of the lateral flow pipe and at the bottom of the lateral flow pipe, and the electromagnetic switch controls the circulation of slurry in the entire steel sleeve, and the specific construction method is as follows: Step 1: Steel sleeve preparation The diameter of the steel sleeve is set to be 1.1-1.2 times the diameter of the lead hole, the length of the steel sleeve is 1m-6m, one end of the steel sleeve is semi-closed, that is, a hole is opened in the middle of the closed end plate, the diameter of the hole is 1cm-2cm larger than the diameter of the jet grouting drill rod, and the periphery of the hole is sealed with a rubber ring; a lateral flow pipe is reserved on the side of the steel sleeve close to the semi-closed end, a pressure gauge and a solenoid valve are installed on the flow pipe, and an electromagnetic switch is installed at the lower part of the lateral flow pipe; Step 2: Drilling Excavation is carried out at the jet grouting hole location. The excavation diameter is 2-3 times the diameter of the steel sleeve. The excavation depth is the same as the length of the steel sleeve. The excavation depth is above the designed jet grouting pile top elevation. Cement soil or solidified soil is backfilled in the excavated hole. The strength of cement soil or solidified soil is greater than the strength of the original soil within the excavation depth. Step 3: Bury the steel sleeve Implant the steel sleeve prepared in step 1 into the cement soil / solidified soil. The implantation depth is the entire length below the electromagnetic switch. The central axis of the steel sleeve coincides with the central axis of the designed hole position of the jet grouting pile. The semi-enclosed end of the steel sleeve is above the ground. Step 4: Spraying construction Select the jet grouting construction process according to the formation conditions. There are two types of construction processes: when the formation conditions are hard, the first hole is first drilled by the pilot drill and then the jet grouting is performed by the jet grouting drill; when the formation conditions are soft, the jet grouting drill is used to directly drill and lift the drill for jet grouting; first, turn off the electromagnetic switch, insert the jet grouting drill rod into the opening at the semi-closed end of the steel sleeve, and the rubber sealing ring seals the gap between the steel sleeve and the jet grouting drill rod. According to the water level height given in the geological survey report, calculate the distance between the jet grouting construction ground and the water level, and set the threshold of the pressure gauge to 1.0-1.2 times the pressure caused by the water level difference. When the pressure gauge reaches the set threshold, it transmits a signal to the electromagnetic valve, and the electromagnetic valve makes a switch action; when the jet grouting drill rod is lowered to the electromagnetic switch position, turn on the electromagnetic switch, and the jet grouting drill rod passes through the electromagnetic switch position; Step 5: Re-slurry treatment completes the construction According to the switch of the solenoid valve, the return slurry flows out from the lateral flow pipe to the ground surface and is drained to the mud pool through an external pipe. When the construction of the entire rotary jet pile is completed, the rotary jet drill rod continues to be lifted. When the rotary jet drill rod is higher than the electromagnetic switch, the electromagnetic switch is turned off, and the drill rod continues to be lifted until it is completely lifted out. The rotary jet construction is completed, and the steel sleeve remains in its original position until it is pulled out after the rotary jet pile is initially solidified.
[0006] Beneficial technical effects brought by the present invention: By blocking the return grouting channel of the rotary jet pile at the construction site below the water level line, the blocking pressure is the same as the head pressure formed by the water level difference. When the blocking pressure reaches the set value, the return grouting channel is smooth. When the blocking pressure does not reach the set value, the return grouting channel is blocked by the solenoid valve and the slurry cannot be discharged smoothly. In this way, the pile body is constructed under pressure, which minimizes the impact of pressurized water on the rotary jet pile. BRIEF DESCRIPTION OF THE DRAWINGS
[0007] Figure 1 It is a cross-sectional schematic diagram of the overall structure of a complete set of rotary grouting construction method under high pressure water conditions of the present invention; Figure 2 It is a structural diagram of a rigid sleeve in a complete set of rotary grouting construction method under high pressure water conditions of the present invention; Among them, 1- rotary jet drilling rig, 2- rotary jet drill rod, 3- steel sleeve, 4- solenoid valve, 5- pressure gauge, 6- water level line, 7- electromagnetic switch. DETAILED DESCRIPTION
[0008] The present invention is further described in detail below with reference to the accompanying drawings and specific embodiments: Embodiment 1:
[0009] like Figure 1-2 As shown, a complete set of rotary grouting construction method under high pressure water conditions is constructed by rotary grouting equipment, including a rotary grouting drill rod 2, a rotary grouting drill rig 1, and also including a steel sleeve 3, a solenoid valve 4, a pressure gauge 5, and an electromagnetic switch 7, wherein the steel sleeve 3 is inserted into the designed hole position, and the end of the steel sleeve 3 above the ground is a semi-closed end, and a lateral flow pipe is opened in the part of the steel sleeve 3 above the ground, and the solenoid valve 4 and the pressure gauge 5 are arranged on the lateral flow pipe. The solenoid valve 4 and the pressure gauge 5 are transmitted through signals, and the pressure threshold monitored by the pressure gauge 5 controls the opening and closing of the solenoid valve 4, and the electromagnetic switch 7 is arranged inside the steel sleeve 3 near the side of the lateral flow pipe and at the bottom of the lateral flow pipe. The electromagnetic switch 7 controls the circulation of slurry in the entire steel sleeve 3. The specific construction method is as follows: Step 1: Steel sleeve 3 preparation The diameter of the steel sleeve 3 is set to be 1.1-1.2 times the diameter of the lead hole, the length of the steel sleeve 3 is 1m-6m, one end of the steel sleeve 3 is semi-closed, that is, a hole is opened in the middle of the closed end plate, the diameter of the opening is 1cm-2cm larger than the diameter of the rotary jet drilling rod 2, and the periphery of the opening is sealed with a rubber ring; a lateral flow pipe is reserved on the side of the steel sleeve 3 close to the semi-closed end, a pressure gauge 5 and an electromagnetic valve 4 are installed on the flow pipe, and an electromagnetic switch 7 is installed at the lower part of the lateral flow pipe; Step 2: Drilling Excavation is carried out at the jet-jet hole position, the excavation diameter is 2-3 times the diameter of the steel sleeve 3, the excavation depth is the same as the length of the steel sleeve 3, the excavation depth is above the designed jet-jet pile top elevation, and cement soil or solidified soil is backfilled in the excavated hole. The strength of the cement soil or solidified soil is greater than the strength of the original soil in the excavation depth; Step 3: Bury the steel sleeve Implant the steel sleeve 3 prepared in step 1 into the cement soil / solidified soil, the implantation depth is the entire length below the electromagnetic switch 7, the central axis of the steel sleeve 3 coincides with the central axis of the designed hole position of the jet grouting pile, and the semi-enclosed end of the steel sleeve 3 is above the ground; Step 4: Spraying construction The rotary jetting construction process is selected according to the formation conditions. The construction process is divided into two types: when the formation conditions are relatively hard, the first hole is first drilled by the drilling rig and then the rotary jetting drilling rig 1 is used for rotary jetting; when the formation conditions are relatively soft, the rotary jetting drilling rig 1 is used to directly drill and lift the drill for rotary jetting; first, the electromagnetic switch 7 is turned off, and the rotary jetting drill rod 2 is inserted into the opening at the semi-closed end of the steel sleeve 3. The rubber sealing ring seals the gap between the steel sleeve 3 and the rotary jetting drill rod 2. According to the height of the water level line 6 given in the geological survey report, the distance between the rotary jetting construction ground and the water level line 6 is calculated, and the threshold of the pressure gauge 5 is set to 1.0-1.2 times the pressure caused by the water level difference. When the pressure gauge 5 reaches the set threshold, it transmits a signal to the electromagnetic valve 4, and the electromagnetic valve 4 makes a switch action; when the rotary jetting drill rod 2 is lowered to the position of the electromagnetic switch 7, the electromagnetic switch 7 is turned on, and the rotary jetting drill rod 2 passes through the position of the electromagnetic switch 7; Step 5: Re-slurry treatment completes the construction According to the switch of the electromagnetic valve, the return slurry flows out from the lateral flow pipe to the ground surface and is drained to the mud pool through an external pipe. When the construction of the entire rotary jet pile is completed, the rotary jet drill rod 2 continues to be lifted. When the rotary jet drill rod 2 is higher than the electromagnetic switch 7, the electromagnetic switch 7 is turned off, and the drill rod 2 continues to be lifted until it is completely lifted out and the rotary jet construction is completed. The steel sleeve 3 remains in its original position until it is pulled out after the rotary jet pile is initially solidified. Embodiment 2:
[0010] like Figure 1-2As shown, a complete set of rotary grouting construction method under high-pressure water conditions is constructed using rotary grouting equipment, including a rotary grouting drill rod 2, a rotary grouting drill rig 1, and also including a steel sleeve 3, a solenoid valve 4, a pressure gauge 5, and an electromagnetic switch 7, wherein the steel sleeve 3 is inserted into the designed hole position, and the end of the steel sleeve 3 above the ground is a semi-closed end, and a lateral flow pipe is opened in the part of the steel sleeve 3 above the ground, and the solenoid valve 4 and the pressure gauge 5 are arranged on the lateral flow pipe. Signals are transmitted between the solenoid valve 4 and the pressure gauge 5, and the pressure threshold monitored by the pressure gauge 5 controls the opening and closing of the solenoid valve 4, and the electromagnetic switch 7 is arranged on the side of the steel sleeve 3 near the lateral flow pipe and at the lower part of the lateral flow pipe. The electromagnetic switch 7 controls the circulation of the slurry in the entire steel sleeve 3. The specific construction method is as follows: the electromagnetic valve and the pressure gauge 5 are data transmission. The pressure gauge 5 monitors the pressure of the return slurry. For example, if the construction ground is 6m below the water level line 6, then the water head pressure on the ground is 0.6MPa. Therefore, the opening and closing threshold of the pressure gauge 5 is 0.6MPa. When it reaches 0.6MPa, the electromagnetic valve 4 opens and the return slurry is discharged smoothly. When the pressure value is lower than 0.6MPa, the electromagnetic valve 4 is closed, and the return slurry cannot be discharged smoothly. The pressure in the ground increases. When the return slurry at the ground reaches 0.6MPa again, the electromagnetic valve 4 opens and the return slurry is discharged smoothly. The electromagnetic switch 7 is used to prevent the jet grouting phenomenon from still occurring at the moment before the jet grouting drill rod 2 is inserted and after it is pulled out. Therefore, adding the electromagnetic switch 7 is to add a blockage. When the jet grouting drill rod 2 is lowered, the upper part of the rigid sleeve 3 is not closed, and the electromagnetic switch 7 is closed, the pressure in the ground will not be released. When the jet grouting drill rod 2 is lifted, the electromagnetic switch 7 is opened, the jet grouting drill rod 2 and the rigid sleeve 3 are closed, and the pressure in the ground will not be released. When it is lifted to the upper part of the electromagnetic switch 7 and below the upper end of the rigid sleeve 3, the electromagnetic switch 7 is closed, and the pressure in the ground will not be released. In this way, there will be no release of pressure in the ground during the entire construction process.
[0011] Step 1: Steel sleeve 3 preparation The diameter of the steel sleeve 3 is set to be 1.1-1.2 times the diameter of the lead hole, the length of the steel sleeve 3 is 1m-6m, one end of the steel sleeve 3 is semi-closed, that is, a hole is opened in the middle of the closed end plate, the diameter of the hole is 1cm-2cm larger than the diameter of the rotary jet drill rod 2, and the periphery of the hole is sealed with a rubber ring; a lateral flow pipe is reserved on the side of the steel sleeve 3 close to the semi-closed end, a pressure gauge 5 and an electromagnetic valve 4 are installed on the flow pipe, and an electromagnetic switch 7 is installed at the lower part of the lateral flow pipe. The diameter of the steel sleeve is set according to the diameter of the lead hole. The diameter is determined by the steel sleeve, and the diameter of the steel sleeve is slightly larger than the diameter of the pilot hole. After the construction of the pilot hole drill rod or the rotary jet drill rod 2, the soil in the steel sleeve is basically cleaned up, and the return slurry flows along the inside of the steel sleeve. The length of the steel sleeve is determined according to the soil conditions. For example, if the head pressure is 0.6MPa, then if the surrounding area of the steel sleeve is clay, and the specific gravity of the soil is 18kg / m3, then the minimum insertion depth of the steel sleeve is 3.3m. In order to ensure safety, the depth can be set to 4m or above.
[0012] Step 2: Drilling Excavation is carried out at the rotary jet hole location, and the excavation diameter is 2-3 times the diameter of the steel sleeve 3. The excavation depth is the same as the length of the steel sleeve 3. The excavation depth is above the designed rotary jet pile top elevation. Cement soil or solidified soil is backfilled in the excavated hole. The strength of the cement soil or solidified soil is greater than the strength of the original soil within the excavation depth; backfilling with cement soil or solidified soil after excavation is to bond the steel sleeve 3 to the surrounding soil to ensure that the return slurry will not form a new channel from the outside of the steel sleeve 3 to flow away.
[0013] Step 3: Bury the steel sleeve Implant the steel sleeve 3 prepared in step 1 into the cement soil / solidified soil, the implantation depth is the entire length below the electromagnetic switch 7, the central axis of the steel sleeve 3 coincides with the central axis of the designed hole position of the jet grouting pile, and the semi-enclosed end of the steel sleeve 3 is above the ground; Step 4: Spraying construction The rotary jetting construction process is selected according to the formation conditions. The construction process is divided into two types: when the formation conditions are relatively hard, the first hole is first drilled by the drilling rig and then the rotary jetting drilling rig 1 is used for rotary jetting; when the formation conditions are relatively soft, the rotary jetting drilling rig 1 is used to directly drill and lift the drill for rotary jetting; first, the electromagnetic switch 7 is turned off, and the rotary jetting drill rod 2 is inserted into the opening at the semi-closed end of the steel sleeve 3. The rubber sealing ring seals the gap between the steel sleeve 3 and the rotary jetting drill rod 2. According to the height of the water level line 6 given in the geological survey report, the distance between the rotary jetting construction ground and the water level line 6 is calculated, and the threshold of the pressure gauge 5 is set to 1.0-1.2 times the pressure caused by the water level difference. When the pressure gauge 5 reaches the set threshold, it transmits a signal to the electromagnetic valve 4, and the electromagnetic valve 4 makes a switch action; when the rotary jetting drill rod 2 is lowered to the position of the electromagnetic switch 7, the electromagnetic switch 7 is turned on, and the rotary jetting drill rod 2 passes through the position of the electromagnetic switch 7; Step 5: Re-slurry treatment completes the construction According to the switch of the electromagnetic valve, the return slurry flows out from the lateral flow pipe to the ground surface and is drained to the mud pool through an external pipe. When the construction of the entire rotary jet pile is completed, the rotary jet drill rod 2 continues to be lifted. When the rotary jet drill rod 2 is higher than the electromagnetic switch 7, the electromagnetic switch 7 is turned off, and the drill rod 2 continues to be lifted until it is completely lifted out and the rotary jet construction is completed. The steel sleeve 3 remains in its original position until it is pulled out after the rotary jet pile is initially solidified.
[0014] In the description of the embodiments of the present invention, it should be understood that the orientation or positional relationship indicated by the terms "upper" and "lower" and the like is based on the orientation or positional relationship shown in the accompanying drawings, and is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention. In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "set" and "connection" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be directly connected, or indirectly connected through an intermediate medium, or it can be internal communication between two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood by specific circumstances.
[0015] Of course, the above description is not a limitation of the present invention, and the present invention is not limited to the above examples. Changes, modifications, additions or substitutions made by technicians in this technical field within the essential scope of the present invention also fall within the protection scope of the present invention.
Claims
1. A complete set of rotary grouting construction method under high pressure water conditions, characterized in that: The construction adopts the rotary grouting equipment, including the rotary grouting drill rod, the rotary grouting drill, and also includes the steel sleeve, the solenoid valve, the pressure gauge, and the solenoid switch. The steel sleeve is inserted into the designed hole position, and the end of the steel sleeve above the ground is a semi-closed end. The part of the steel sleeve above the ground is provided with a lateral flow pipe, and the lateral flow pipe is provided with a solenoid valve and a pressure gauge. The solenoid valve and the pressure gauge are transmitted through signals, and the pressure threshold monitored by the pressure gauge controls the opening and closing of the solenoid valve. The solenoid switch is arranged inside the steel sleeve near the side of the lateral flow pipe and at the bottom of the lateral flow pipe. The solenoid switch controls the circulation of the slurry in the entire steel sleeve. The specific construction method is as follows: Step 1: Steel sleeve preparation The diameter of the steel sleeve is set to be 1.1-1.2 times the diameter of the lead hole, the length of the steel sleeve is 1m-6m, one end of the steel sleeve is semi-closed, that is, a hole is opened in the middle of the closed end plate, the diameter of the hole is 1cm-2cm larger than the diameter of the jet grouting drill rod, and the periphery of the hole is sealed with a rubber ring; a lateral flow pipe is reserved on the side of the steel sleeve close to the semi-closed end, a pressure gauge and a solenoid valve are installed on the flow pipe, and an electromagnetic switch is installed at the lower part of the lateral flow pipe; Step 2: Drilling Excavation is carried out at the jet grouting hole location. The excavation diameter is 2-3 times the diameter of the steel sleeve. The excavation depth is the same as the length of the steel sleeve. The excavation depth is above the designed jet grouting pile top elevation. Cement soil or solidified soil is backfilled in the excavated hole. The strength of cement soil or solidified soil is greater than the strength of the original soil within the excavation depth. Step 3: Bury the steel sleeve Implant the steel sleeve prepared in step 1 into the cement soil / solidified soil. The implantation depth is the entire length below the electromagnetic switch. The central axis of the steel sleeve coincides with the central axis of the designed hole position of the jet grouting pile. The semi-enclosed end of the steel sleeve is above the ground. Step 4: Spraying construction Select the jet grouting construction process according to the formation conditions. There are two types of construction processes: when the formation conditions are hard, the first hole is first drilled by the pilot drill and then the jet grouting is performed by the jet grouting drill; when the formation conditions are soft, the jet grouting drill is used to directly drill and lift the drill for jet grouting; first, turn off the electromagnetic switch, insert the jet grouting drill rod into the opening at the semi-closed end of the steel sleeve, and the rubber sealing ring seals the gap between the steel sleeve and the jet grouting drill rod. According to the water level height given in the geological survey report, calculate the distance between the jet grouting construction ground and the water level, and set the threshold of the pressure gauge to 1.0-1.2 times the pressure caused by the water level difference. When the pressure gauge reaches the set threshold, it transmits a signal to the electromagnetic valve, and the electromagnetic valve makes a switch action; when the jet grouting drill rod is lowered to the electromagnetic switch position, turn on the electromagnetic switch, and the jet grouting drill rod passes through the electromagnetic switch position; Step 5: Re-slurry treatment completes the construction According to the switch of the solenoid valve, the return slurry flows out from the lateral flow pipe to the ground surface and is drained to the mud pool through an external pipe. When the construction of the entire rotary jet pile is completed, the rotary jet drill rod continues to be lifted. When the rotary jet drill rod is higher than the electromagnetic switch, the electromagnetic switch is turned off, and the drill rod continues to be lifted until it is completely lifted out. The rotary jet construction is completed, and the steel sleeve remains in its original position until it is pulled out after the rotary jet pile is initially solidified.