Cast-in-place pile construction method

Abstract

The invention discloses a cast-in-place pile construction method which comprises the steps that a construction area is monitored, if hole collapse and retaining wall mud loss occur in the construction area, geological conditions of the construction area are analyzed, whether unfavorable geological factors exist or not is judged, and the unfavorable geological factors include backfilled garbage soil in the construction area; if yes, excavation inspection is carried out, and the distribution condition of the garbage soil is recorded; according to the distribution condition of the garbage soil backfilled in the construction area, new soil is used for replacing and filling the garbage soil, and the replacing and filling depth reaches 6 m; cement paste is injected into the soil body at high pressure through a high-pressure injection method, a plurality of reinforcing pile bodies are formed, the distance between every two adjacent reinforcing pile bodies in the multiple reinforcing pile bodies is 0.5 m, and the reinforcing depth reaches 6 m; and after the soil body is reinforced, cast-in-place pile construction is conducted in the construction area. Foundation conditions can be improved, hole collapse and arm guard mud loss are avoided, and the construction quality of the cast-in-place pile is improved.

Description

Technical Field

[0001] The invention relates to the technical field of building construction, and in particular to a cast-in-place pile construction method. Background Art

[0002] In the field of foundation treatment technology, traditional bored pile construction methods often face serious problems of hole collapse and wall mud loss when dealing with complex geological conditions, especially in areas with backfilled construction waste. These adverse geological factors increase the difficulty of construction, which not only affects the construction progress, but also has a serious impact on the construction quality. In addition, although the simple soil replacement method can improve the foundation conditions to a certain extent, since the stability of the newly filled soil is difficult to guarantee, hole collapse and cross-hole phenomena may still occur in the subsequent bored pile construction. Summary of the invention

[0003] An object of the present invention is to solve at least the above problems and / or disadvantages and to provide at least the advantages which will be described hereinafter.

[0004] An object of the present invention is to provide a bored pile construction method, which improves foundation conditions by replacing garbage soil and reinforcing the soil body using a high-pressure jet reinforcement method, avoids hole collapse and arm mud loss during bored pile construction, ensures the smooth progress of bored pile construction, and improves the quality of bored pile construction.

[0005] In order to achieve these purposes and other advantages according to the present invention, a cast-in-place pile construction method is provided, comprising:

[0006] Step 1: Problem identification:

[0007] During the construction of bored piles, the construction area is monitored. If there is a hole collapse or loss of retaining wall slurry in the construction area, the problem identification mechanism is activated to analyze the geological conditions of the construction area to determine whether there are adverse geological factors, including the presence of garbage backfill in the construction area;

[0008] Step 2: Excavation inspection:

[0009] If it is determined that the construction area has the adverse geological factors, the construction area is excavated and inspected, and the distribution of the garbage soil backfilled in the construction area is recorded;

[0010] Step 3: Replace garbage soil with other filling materials:

[0011] According to the distribution of the garbage soil backfilled in the construction area, the garbage soil backfilled in the construction area is replaced with new soil, and the replacement depth reaches 6m;

[0012] Step 4: Soil reinforcement:

[0013] The cement slurry is injected into the soil at high pressure by a high-pressure jetting method to form a plurality of reinforced piles, wherein the spacing between two adjacent reinforced piles in the plurality of reinforced piles is 0.5 m, and the reinforcement depth reaches 6 m;

[0014] Step 5: Cast-in-place pile construction:

[0015] After the soil reinforcement is completed, cast-in-place pile construction is carried out in the construction area.

[0016] Preferably, in the cast-in-place pile construction method, in the step three, the garbage soil backfilled in the construction area is replaced with new soil based on the distribution of the garbage soil backfilled in the construction area, including: determining the distribution area of ​​the garbage soil in the construction area, if there are multiple distribution areas of the garbage soil in the construction area, delineating the excavation boundary of each distribution area according to the actual boundary of each distribution area, the excavation boundary of each distribution area expands outward by at least 0.5m compared to the actual boundary of each distribution area, the excavation boundary of each distribution area is rectangular, the garbage soil in each distribution area is excavated along the excavation boundary of each distribution area to form an area to be filled, and new soil is filled in the area to be filled.

[0017] Preferably, in the cast-in-place pile construction method, in the step three, the process of filling new soil into the area to be filled is: each area to be filled is divided into multiple layers to be filled from bottom to top, the depth of each layer to be filled is 0.5m, and new soil is filled into the multiple layers to be filled layer by layer from bottom to top to obtain multiple filling layers in sequence, and after filling each layer to be filled, each filling layer is compacted.

[0018] Preferably, in the cast-in-place pile construction method, in the step 4, during the construction process of injecting cement slurry into the soil at high pressure by a high-pressure jetting method to form multiple reinforced pile bodies, after the shotcrete pipe sinks to the designed depth, the shotcrete pipe is sprayed at a jet pressure of 20-30MPa, and rotates at a speed of 20-25 rpm for 30s-1min, thereby forming a pile seat portion, and then the shotcrete pipe is lifted at a lifting speed of 0.2-0.3m / min, the jet pressure during the lifting process is 30-40MPa, and the shotcrete pipe is rotated at a speed of 25-30 rpm, thereby forming a pile body portion, until the shotcrete pipe reaches the pile head position, the shotcrete pipe is sprayed at a jet pressure of 20-30MPa, and rotates at a speed of 20-25 rpm for 30s-1min, thereby forming a pile head portion, and finally the shotcrete pipe is lifted to the ground.

[0019] Preferably, in the cast-in-place pile construction method, in the step four, during the construction process of injecting cement slurry into the soil at high pressure by using a high-pressure jetting method to form a plurality of reinforced pile bodies, during the construction of the pile body part, the shotcrete pipe is constructed in sections, and each section of the shotcrete pipe construction includes a lifting stage and a dwell stage. The shotcrete pipe is lifted by 0.2m in each lifting stage, enters the dwell stage at the current position and stays for 5s, and then is lifted by 0.2m in the next lifting stage, and then enters the dwell stage at the current position and stays for 5s, and the above process is repeated until the construction of the pile body part is completed.

[0020] Preferably, in the cast-in-place pile construction method, in the step 4, during the construction of the pile body, the shotcrete pipe is constructed in sections, and the injection pressure of the shotcrete pipe in each dwell stage is 3 MPa less than the injection pressure in the corresponding lifting stage.

[0021] Preferably, in the cast-in-place pile construction method, in the step four, during the construction of the pile body, the shotcrete pipe is constructed in sections, and the injection pressure of the shotcrete pipe in each dwell stage is 30-37MPa, and the injection pressure in the corresponding lifting stage is 33-40MPa.

[0022] The present invention has at least the following beneficial effects:

[0023] The present invention provides a bored pile construction method, comprising: step 1, problem identification: during the bored pile construction process, the construction area is monitored, if the construction area has collapsed holes and the wall protection slurry is lost, the problem identification mechanism is started, the geological conditions of the construction area are analyzed, and it is determined whether there are unfavorable geological factors, and the unfavorable geological factors include the existence of garbage soil backfilled in the construction area; step 2, excavation inspection: if it is determined that the construction area has the unfavorable geological factors, the construction area is excavated and inspected, and the distribution of the garbage soil backfilled in the construction area is recorded;

[0024] Step 3, garbage soil replacement: according to the distribution of garbage soil backfilled in the construction area, new soil is used to replace the garbage soil backfilled in the construction area, and the replacement depth reaches 6m; Step 4, soil reinforcement: high-pressure injection method is used to inject cement slurry into the soil at high pressure to form multiple reinforced piles, and the spacing between two adjacent reinforced piles in the multiple reinforced piles is 0.5m, and the reinforcement depth reaches 6m; Step 5, cast-in-place pile construction: after the soil reinforcement is completed, cast-in-place pile construction is carried out in the construction area. The present invention monitors the construction situation of the construction area to determine whether there are unfavorable geological factors for backfilling with garbage soil in the construction area. If it is determined that there are, the foundation conditions are improved by replacing the garbage soil and reinforcing the soil using a high-pressure injection reinforcement method, so as to avoid the occurrence of hole collapse and arm guard mud loss during cast-in-place pile construction, ensure the smooth progress of cast-in-place pile construction, and improve the quality of cast-in-place pile construction.

[0025] Other advantages, objectives and features of the present invention will be embodied in part through the following description, and in part will be understood by those skilled in the art through study and practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 The present invention is a flowchart of a method for constructing a bored pile according to an embodiment of the present invention. DETAILED DESCRIPTION

[0027] The present invention is further described in detail below in conjunction with the accompanying drawings so that those skilled in the art can implement the invention with reference to the description.

[0028] like Figure 1 As shown, an embodiment of the present invention provides a cast-in-place pile construction method, comprising:

[0029] Step 1: Problem identification: During the bored pile construction process, the construction area is monitored. If there is a hole collapse or loss of retaining wall slurry in the construction area, the problem identification mechanism is activated to analyze the geological conditions of the construction area to determine whether there are adverse geological factors, including the presence of backfilled garbage soil in the construction area.

[0030] In step 1, during the construction of the bored piles, once serious hole collapse and serious loss of retaining wall slurry are found, the problem identification process should be started immediately. In addition to the preliminary judgment that the geological conditions are complex, the root causes of the hole collapse and slurry loss should be analyzed in depth in combination with geological exploration reports, historical construction data and on-site surveys. In particular, possible adverse geological factors (such as backfilled construction waste, etc.) should be identified and corresponding countermeasures should be taken.

[0031] Step 2: Excavation inspection: If it is determined that the construction area has the adverse geological factors, an excavation inspection is performed on the construction area to record the distribution of the garbage soil backfilled in the construction area.

[0032] In step 2, excavation inspection is a key step in confirming adverse geological conditions. During the excavation process, appropriate mechanical equipment and tools should be used to ensure that the depth and breadth of the excavation can meet the inspection requirements. For adverse geological factors such as construction waste found, their distribution range, thickness, properties and other information should be recorded in detail to provide a basis for subsequent processing.

[0033] Step 3: Replacement of garbage soil: Based on the distribution of the garbage soil backfilled in the construction area, new soil is used to replace the garbage soil backfilled in the construction area, and the replacement depth reaches 6m.

[0034] In step 3, when replacing the garbage soil, the quality and performance of the replacement soil should be ensured to meet the design requirements. Before replacement, the quality of the new soil should be tested and evaluated to ensure that it can provide sufficient support and prevent the recurrence of collapse. At the same time, the replacement depth and quality should be strictly controlled during the replacement process to ensure that the replacement effect reaches the expected goal.

[0035] Due to time constraints, the replacement soil may not be able to undergo long-term consolidation. Therefore, the stability of the replacement soil can be evaluated regularly during the subsequent construction process. During the evaluation process, existing monitoring equipment and methods can be used to conduct real-time monitoring and data analysis of indicators such as deformation and settlement of the replacement soil. If the stability of the replacement soil is found to be insufficient, reinforcement measures should be taken in a timely manner.

[0036] Step 4: Soil reinforcement: Use high-pressure jetting to inject cement slurry into the soil at high pressure to form multiple reinforced piles. The distance between two adjacent reinforced piles in the multiple reinforced piles is 0.5m, and the reinforcement depth reaches 6m.

[0037] High-pressure jetting reinforcement is an effective way to solve the problem of insufficient stability of fill soil. During the reinforcement process, it is necessary to ensure that the diameter, pile spacing and reinforcement depth of the high-pressure jetting piles meet the design requirements. At the same time, the parameters such as jetting pressure and jetting speed are controlled to ensure that the solidifying material can fully penetrate into the soil and form a stable pile body.

[0038] Step 5: Cast-in-place pile construction: After the soil reinforcement is completed, cast-in-place pile construction is carried out in the construction area.

[0039] During the construction of bored piles, if there is a serious hole collapse and the wall protection slurry is lost, the method provided by the present invention can effectively identify the root cause of the problem, that is, the construction area may have backfilled construction waste and other unfavorable geological factors. Through excavation inspection, it can be intuitively found that there is a large amount of backfilled construction waste in the construction area. These garbage soils are loose and cannot provide stable support for bored piles, which is the main reason for the hole collapse and wall protection slurry loss. In order to improve the foundation conditions, the present invention proposes a method for replacing garbage soil. By replacing garbage soil with a depth of 6m, it is ensured that the newly replaced soil can provide sufficient support, thereby preventing the occurrence of hole collapse and other phenomena. However, due to time constraints, the replacement soil may not be able to undergo long-term consolidation, resulting in the problem of hole collapse and string holes in the subsequent bored pile construction. In order to solve the problem of insufficient stability of the replacement soil, the present invention introduces high-pressure jetting reinforcement technology. By adopting double-row high-pressure rotary jet piles with a diameter of 650mm, cement slurry and other solidifying materials are sprayed into the soil at high pressure to form a stable pile structure. This reinforcement method can significantly improve the overall stability of the soil and prevent the occurrence of hole collapse and string holes. The spacing between two adjacent reinforcement piles is set to 0.5m to ensure the uniformity and continuity of the reinforcement effect. The reinforcement depth reaches 6m, which is sufficient to meet the construction requirements. Finally, after the soil reinforcement is completed, the cast-in-place pile construction is carried out at the center line of the reinforcement area. As the foundation conditions have been significantly improved, the cast-in-place pile construction can proceed smoothly, ensuring the quality and safety of the project.

[0040] Step 5 During the construction of the cast-in-place pile, the cast-in-place pile can be arranged between two adjacent reinforcement pile bodies, as long as the reinforcement pile bodies are avoided during construction. Preferably, a cast-in-place pile can be arranged in the middle of every two adjacent reinforcement pile bodies.

[0041] In a preferred embodiment, in the cast-in-place pile construction method, in the step three, the garbage soil backfilled in the construction area is replaced with new soil based on the distribution of the garbage soil backfilled in the construction area, including: determining the distribution area of ​​the garbage soil in the construction area, if there are multiple distribution areas of the garbage soil in the construction area, delineating the excavation boundary of each distribution area according to the actual boundary of each distribution area, the excavation boundary of each distribution area expands outward by at least 0.5m compared to the actual boundary of each distribution area, the excavation boundary of each distribution area is rectangular, and the garbage soil in each distribution area is excavated along the excavation boundary of each distribution area to form an area to be filled, and new soil is filled in the area to be filled.

[0042] Specifically, the garbage soil in the construction area is processed according to the specific distribution of the garbage soil in the construction area. First, there are multiple distribution areas of garbage soil in the construction area. The excavation boundary is delineated according to the actual boundary of each distribution area. In order to ensure that the garbage soil in each distribution area is completely removed, the excavation boundary is designed to be a larger range, that is, the excavation boundary expands outward by at least 0.5m. For example, the actual boundary of the distribution area is an irregular shape, and the excavation boundary is a rectangle, then the excavation boundary of the rectangle should be able to include the actual boundary, and the distance from any point on the four sides of the excavation boundary to the actual boundary should be greater than or equal to 0.5m. Afterwards, fill in new soil in the formed area to be filled.

[0043] In a preferred embodiment, in the cast-in-place pile construction method, in the step three, the process of filling new soil into the area to be filled is: each area to be filled is divided into multiple layers to be filled from bottom to top, and the depth of each layer to be filled is 0.5m, and new soil is used to fill the multiple layers to be filled layer by layer from bottom to top to obtain multiple filling layers in sequence, and after filling each layer to be filled, each filling layer is compacted.

[0044] Specifically, the present invention also divides the area to be filled into multiple layers to be filled, each layer to be filled has a depth of 0.5m, and then fills layer by layer, and compacts each layer after filling. Based on this design, the overall stability of the filled soil can be improved, and the collapse of the hole and the loss of mud from the arm guard can be avoided during the construction of the cast-in-place pile.

[0045] In a preferred embodiment, in the cast-in-place pile construction method, in the step 4, during the construction process of injecting cement slurry into the soil at high pressure through high-pressure injection equipment to form a reinforced pile body, after the shotcrete pipe sinks to the designed depth, the shotcrete pipe is sprayed at a spray pressure of 20-30MPa, and rotates at a speed of 20-25 rpm for 30s-1min, thereby forming a pile seat part, and then the shotcrete pipe is lifted at a lifting speed of 0.2-0.3m / min, the injection pressure during the lifting process is 30-40MPa, and the shotcrete pipe is rotated at a speed of 25-30 rpm, thereby forming a pile body part, until the shotcrete pipe reaches the pile head position, the shotcrete pipe is sprayed at a spray pressure of 20-30MPa, and rotates at a speed of 20-25 rpm for 30s-1min, thereby forming a pile head part, and finally the shotcrete pipe is lifted to the ground.

[0046] When reinforcing the soil, the reinforced pile can be decomposed into three parts, namely the pile head, the pile body and the pile seat. For the pile seat and pile head, in order to improve the stability of the reinforced pile, the volume of these two parts can be increased. Therefore, during construction, the injection pressure of these two parts must be controlled to be small and the rotation speed must be slow to ensure that the cement slurry is evenly distributed in the soil to form a stable pile head and pile seat. For the pile body, its diameter is smaller than that of the pile head and pile seat, and its injection pressure is greater and the rotation speed is faster, which can increase the construction speed.

[0047] In a preferred embodiment, in the cast-in-place pile construction method, in the step four, during the construction process of injecting cement slurry into the soil at high pressure through high-pressure injection equipment to form a reinforced pile body, during the construction of the pile body part, the shotcrete pipe is constructed in sections, and each section of the shotcrete pipe construction includes a lifting stage and a dwell stage. The shotcrete pipe is lifted by 0.2m in each lifting stage, enters the dwell stage at the current position and stays for 5s, and then is lifted by 0.2m in the next lifting stage, and then enters the dwell stage at the current position and stays for 5s, and the above process is repeated until the construction of the pile body part is completed, wherein the injection pressure of the shotcrete pipe in the dwell stage is 5MPa less than the injection pressure in the lifting stage.

[0048] When constructing the pile body, in order to ensure that the cement slurry is evenly distributed in the soil and improve the construction quality, the pile body can be divided into multiple construction sections. Each construction section is divided into a lifting stage and a dwelling stage. The shotcrete pipe is lifted upward in the lifting stage and sprays out cement slurry. In the dwelling stage, it stays at the current depth and sprays out cement slurry at the current depth. In this process, the shotcrete pipe stays at the current depth for a short time, which is equivalent to replenishing cement slurry to the section, avoiding insufficient cement slurry in a certain section of the pile body, which affects the overall strength and stability of the pile body.

[0049] In a preferred embodiment, in the cast-in-place pile construction method, in the step four, during the construction of the pile body, the shotcrete pipe is constructed in sections, and the injection pressure of the shotcrete pipe in each dwell stage is 3 MPa less than the injection pressure in the corresponding lifting stage.

[0050] In each construction stage, the injection pressure in the dwelling stage is lower than that in the lifting stage. In the lifting stage, the shotcrete pipe has already provided most of the cement slurry required for this section. In the dwelling stage, it mainly plays a supplementary role and uses the injection pressure in the dwelling stage to improve the uniformity of cement slurry distribution in the soil. Therefore, the injection pressure in the dwelling stage can be slightly lower than that in the lifting stage.

[0051] In a preferred embodiment, in the cast-in-place pile construction method, in the step four, during the construction of the pile body, the shotcrete pipe is constructed in sections, and the injection pressure of the shotcrete pipe in each dwell stage is 30-37MPa, and the injection pressure in the corresponding lifting stage is 33-40MPa.

[0052] In each construction stage, the injection pressure in the dwelling stage is lower than that in the lifting stage. In the lifting stage, the shotcrete pipe has already provided most of the cement slurry required for this section. In the dwelling stage, it mainly plays a supplementary role and uses the injection pressure in the dwelling stage to improve the uniformity of cement slurry distribution in the soil. Therefore, the injection pressure in the dwelling stage can be slightly lower than that in the lifting stage.

[0053] A specific embodiment is provided below to illustrate the cast-in-place pile construction method.

[0054] This embodiment provides a cast-in-place pile construction method, comprising the following steps:

[0055] Step 1: Problem Identification

[0056] S1: During the construction of cast-in-place piles, pay close attention to construction phenomena through monitoring equipment and on-site observation. Once the hole collapse and serious loss of retaining wall mud occur, immediately start the problem identification mechanism. Through the preliminary analysis of the geological conditions in the construction area, determine whether there are adverse geological factors.

[0057] S2: Stay vigilant, discover and record abnormal situations in time to provide accurate problem location for subsequent steps. At the same time, ensure the accuracy and reliability of monitoring equipment.

[0058] Step 2: Excavation inspection

[0059] S1: After confirming that there are geological problems, conduct excavation inspection. Use excavators and other equipment to carefully excavate the soil in the construction area, and observe and record the backfill construction waste.

[0060] S2: Ensure safety during excavation to avoid secondary damage to the surrounding environment. At the same time, record the distribution and properties of the garbage soil in detail to provide a basis for subsequent replacement work. In addition, pay attention to environmental protection issues and reasonably handle the waste generated by excavation.

[0061] Step 3: Replace the garbage soil

[0062] S1: According to the results of the excavation inspection, the garbage soil is replaced. New soil that can provide sufficient support is selected for replacement, and the replacement depth reaches 6m.

[0063] S2: During the replacement process, the quality of the new soil must be ensured to avoid mixing with impurities. At the same time, the soil must be filled and compacted in layers to ensure that the replaced soil can provide stable support. In addition, attention must be paid to environmental issues and waste generated by replacement must be properly handled.

[0064] Step 4: Stability assessment of fill soil

[0065] S1: After the replacement soil is completed, the stability is evaluated. By observing the surface condition of the replacement soil and measuring its settlement, it is determined whether its stability meets the construction requirements.

[0066] S2: The assessment process must be rigorous and meticulous to ensure the accuracy of the data. If the stability of the replacement soil does not meet the requirements, further measures need to be taken to reinforce it. At the same time, the safety and accuracy of the assessment process must be ensured.

[0067] Step 5: High-pressure spray reinforcement

[0068] S1: Double rows of 650mm diameter high-pressure jet grouting piles are used for soil reinforcement. Through high-pressure jetting equipment, cement slurry and other solidifying materials are injected into the soil at high pressure to form a stable pile body. The spacing between two adjacent reinforced piles in multiple reinforced piles is set to 0.5m, and the reinforcement depth reaches 6m.

[0069] S2: During the reinforcement process, the injection pressure and injection speed must be strictly controlled to ensure that the solidified material can be evenly distributed in the soil. At the same time, attention should be paid to safe operation to avoid accidents. In addition, attention should be paid to environmental protection issues and waste generated during the injection process should be properly handled.

[0070] Step 6: Cast-in-place pile construction

[0071] S1: After the soil reinforcement is completed, cast-in-place pile construction is carried out at the center line of the reinforcement area. Drilling, steel cage installation, concrete pouring and other operations are carried out according to the design requirements to finally form a stable cast-in-place pile.

[0072] S2: During the construction process, we must strictly abide by the construction specifications and safety operating procedures to ensure the quality and safety of the cast-in-place piles. At the same time, we must monitor and record the construction process in real time to ensure that each step of the operation meets the requirements. In addition, we must pay attention to environmental protection issues and reasonably handle the waste generated during the construction process.

[0073] The cast-in-place pile construction method provided by the present invention can achieve the following technical effects:

[0074] 1. The present invention can significantly reduce or avoid the occurrence of hole collapse during cast-in-place pile construction by identifying problems and taking corresponding replacement measures, thereby improving construction efficiency and safety.

[0075] 2. The present invention improves the mechanical properties of the foundation and the overall stability of the soil through garbage soil replacement and high-pressure jet reinforcement technology, thus providing a solid foundation for subsequent cast-in-place pile construction.

[0076] 3. The present invention aims at the problem of mud loss in the wall protection, and effectively reduces the loss of mud through reinforcement measures and reasonable construction process, saves construction costs, and reduces the impact on the surrounding environment.

[0077] 4. The present invention adopts high-pressure jet reinforcement technology, which can ensure uniform and stable reinforcement effect, improve the quality of cast-in-place pile construction, and enhance the reliability and durability of the structure.

[0078] 5. The present invention is applicable to foundation treatment under various complex geological conditions, and has significant advantages in particular for construction areas containing a large amount of backfilled construction waste, providing an effective solution for similar projects.

[0079] 6. The present invention reduces the problems of hole collapse and mud loss, thus reducing the engineering cost, shortening the construction period and improving the overall economic benefits of the project.

[0080] 7. The present invention has clear steps and strong operability, and is easy to replicate and promote in other engineering projects, providing a useful reference for the development and application of foundation treatment technology.

[0081] 8. The present invention improves the overall bearing capacity and stability of the structure, enhances the safety of the structure and reduces potential risks by improving foundation conditions and strengthening measures.

[0082] Although the embodiments of the present invention have been disclosed above, they are not limited to the applications listed in the specification and the embodiments. It can be fully applied to various fields suitable for the present invention. For those familiar with the art, additional modifications can be easily realized. Therefore, without departing from the general concept defined by the claims and equivalent scope, the present invention is not limited to the specific details and the illustrations shown and described here.

Claims

1. A method for constructing a cast-in-place pile, characterized in that: include: Step 1: Problem identification: During the construction of bored piles, the construction area is monitored. If there is a hole collapse or loss of retaining wall slurry in the construction area, the problem identification mechanism is activated to analyze the geological conditions of the construction area to determine whether there are adverse geological factors, including the presence of garbage backfill in the construction area; Step 2: Excavation inspection: If it is determined that the construction area has the adverse geological factors, the construction area is excavated and inspected, and the distribution of the garbage soil backfilled in the construction area is recorded; Step 3: Replace garbage soil with other filling materials: According to the distribution of the garbage soil backfilled in the construction area, the garbage soil backfilled in the construction area is replaced with new soil, and the replacement depth reaches 6m; Step 4: Soil reinforcement: The cement slurry is injected into the soil at high pressure by a high-pressure jetting method to form a plurality of reinforced piles, wherein the spacing between two adjacent reinforced piles in the plurality of reinforced piles is 0.5 m, and the reinforcement depth reaches 6 m; Step 5: Cast-in-place pile construction: After the soil reinforcement is completed, cast-in-place pile construction is carried out in the construction area.

2. The cast-in-place pile construction method according to claim 1, characterized in that: In the step three, the garbage soil backfilled in the construction area is replaced with new soil according to the distribution of the garbage soil backfilled in the construction area, including: determining the distribution area of ​​the garbage soil in the construction area, if there are multiple distribution areas of the garbage soil in the construction area, delineating the excavation boundary of each distribution area according to the actual boundary of each distribution area, the excavation boundary of each distribution area expands outward by at least 0.5m compared to the actual boundary of each distribution area, the excavation boundary of each distribution area is rectangular, and the garbage soil in each distribution area is excavated along the excavation boundary of each distribution area to form an area to be filled, and filling the new soil in the area to be filled.

3. The cast-in-place pile construction method according to claim 2, characterized in that: In the step three, the process of filling new soil into the area to be filled is: each area to be filled is divided into multiple layers to be filled from bottom to top, the depth of each layer to be filled is 0.5m, and new soil is used to fill the multiple layers to be filled layer by layer from bottom to top to obtain multiple filling layers in sequence, and after filling each layer to be filled, each filling layer is compacted.

4. The cast-in-place pile construction method according to claim 1, characterized in that: In the step 4, during the construction process of injecting cement slurry into the soil body at high pressure to form multiple reinforced pile bodies by using a high-pressure jetting method, after the shotcrete pipe sinks to reach the designed depth, the shotcrete pipe is sprayed at a jet pressure of 20-30MPa, and rotates at a speed of 20-25 rpm for 30s-1min, thereby forming a pile seat part, and then the shotcrete pipe is lifted at a lifting speed of 0.2-0.3m / min, the jet pressure during the lifting process is 30-40MPa, and the shotcrete pipe is rotated at a speed of 25-30 rpm, thereby forming a pile body part, until the shotcrete pipe reaches the pile head position, the shotcrete pipe is sprayed at a jet pressure of 20-30MPa, and rotates at a speed of 20-25 rpm for 30s-1min, thereby forming a pile head part, and finally the shotcrete pipe is lifted to the ground.

5. The cast-in-place pile construction method according to claim 4, characterized in that: In the step 4, during the construction process of injecting cement slurry into the soil at high pressure by using a high-pressure jetting method to form multiple reinforced piles, during the construction of the pile body, the shotcrete pipe is constructed in sections, and each section of the shotcrete pipe construction includes a lifting stage and a dwell stage. The shotcrete pipe is lifted by 0.2m in each lifting stage, enters the dwell stage at the current position and stays for 5s, then is lifted by 0.2m in the next lifting stage, then enters the dwell stage at the current position and stays for 5s, and the above process is repeated until the construction of the pile body is completed.

6. The cast-in-place pile construction method according to claim 5, characterized in that: In the step 4, during the construction of the pile body, the shotcrete pipe is constructed in sections, and the injection pressure of the shotcrete pipe in each dwell stage is 3 MPa less than the injection pressure in the corresponding lifting stage.

7. The cast-in-place pile construction method according to claim 6, characterized in that: In the step 4, during the construction of the pile body, the spraying pipe is constructed in sections, and the spraying pressure of the spraying pipe in each dwelling stage is 30-37 MPa, and the spraying pressure in the corresponding lifting stage is 33-40 MPa.

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