Roadbed layered grouting reinforcement method

Abstract

The invention relates to the technical field of roadbed reinforcement, in particular to a roadbed layered grouting reinforcement method which comprises the following steps: 1) geological exploration; 2) selecting and proportioning materials; (3) preparing equipment; 4) performing site planning and traffic dispersion; (5) drilling and positioning; (6) deep grouting; (7) shallow layer grouting; 8) quality control; 9) quality detection; and 10) settlement observation. Through precise geological survey and layered grouting design, targeted reinforcement of soil layers with different depths is achieved, the overall bearing capacity and stability of the roadbed are effectively improved, the method is short in construction period and small in traffic influence, the grouting material can be recycled, the engineering cost is reduced, the concept of green construction is met, and meanwhile, the method is suitable for being popularized and applied. And high-precision grouting equipment and an intelligent monitoring technology are adopted, so that accurate control of the grouting process is ensured, and the reinforcing effect and the quality reliability are improved.

Description

Technical Field

[0001] The invention relates to the technical field of roadbed reinforcement, in particular to a roadbed layered grouting reinforcement method. Background Art

[0002] As the cornerstone of the road structure, the stability and bearing capacity of the roadbed are crucial to ensure smooth traffic and driving safety. However, with the increase in traffic volume and vehicle load, coupled with the influence of natural factors such as rain erosion and soil loss, the roadbed has gradually suffered from settlement, cracks and other diseases, which seriously threaten road traffic safety. Although traditional roadbed reinforcement methods such as replacement and compaction can improve roadbed performance to a certain extent, they have limitations such as long construction period, high cost and great impact on traffic.

[0003] Therefore, it is necessary to develop a roadbed layered grouting reinforcement method to solve the above-mentioned problems existing in the prior art. Summary of the invention

[0004] The technical problem to be solved by the present invention is to overcome the defects of the above-mentioned technology and provide a roadbed layered grouting reinforcement method.

[0005] To achieve the above purpose, the present invention provides a roadbed layered grouting reinforcement method, which includes the following steps: 1) geological survey: using professional geological exploration equipment and technology to comprehensively detect the soil layer structure within the roadbed range and clarify the distribution of soil layers at different depths; 2) material selection and proportioning: cement is selected as the main grouting material, and admixtures are added according to the characteristics of different soil layers; 3) equipment preparation: prepare a high-precision grouting pump with the function of accurately adjusting the grouting pressure and flow, equip with a grouting pipe with adjustable length and diameter, and install an intelligent pressure sensor and a flow monitor; 4) site planning and traffic diversion: reasonably plan the construction site around the roadbed, formulate a detailed traffic diversion plan, reduce the impact of construction on road traffic, and ensure the safe passage of vehicles and pedestrians; 5) drilling positioning: determine the drilling spacing according to the degree of roadbed damage and soil layer characteristics, and Use measuring instruments to accurately mark the drilling position on the surface; 6) Deep grouting: Connect the grouting pipe to the bottom of the deep borehole, and start the grouting operation after fully stirring the deep grouting material in the grouting pump according to the predetermined ratio of deep grouting materials; 7) Shallow grouting: After the deep grouting is completed and reaches a certain strength, shallow drilling grouting is carried out. The shallow grouting material is prepared according to the previously determined ratio suitable for the shallow soil; 8) Quality control: Conduct quality inspection on the raw materials entering the site, strictly monitor the operation of the grouting equipment during grouting, record the grouting volume of the grouting holes in detail, and provide professional training for on-site operators; 9) Quality inspection: Use non-destructive testing methods to conduct internal structure inspection of the roadbed soil after grouting reinforcement; 10) Settlement observation: Settlement observation points are arranged on the roadbed surface, and settlement observations are carried out regularly before grouting construction, during construction and during road operation.

[0006] Furthermore, in the step 1), the soil layer structure within the roadbed is comprehensively detected, including information on the thickness, type, density, groundwater level depth and changes of each soil layer, and an accurate geological profile is drawn based on the detection results to clarify the distribution of soil layers at different depths, providing an accurate basis for subsequent layered grouting design.

[0007] Furthermore, in the step 2), the admixtures include an early strength agent, an expansive agent, and a fiber admixture. For deep soil, an appropriate amount of early strength agent is added. Considering that the pressure of the deep soil is relatively high, an expansive agent is added to compensate for the shrinkage of the grouting material during the hardening process; for shallow soil, in order to enhance its flexibility and crack resistance, the cement content in the grouting material is reduced and some fiber admixtures are added.

[0008] Furthermore, in the step 3), the intelligent pressure sensor is installed at the outlet of the grouting pump and at the bottom of the grouting hole, and is arranged at intervals along the grouting pipe; the flow monitor is installed at the outlet of the grouting pump and at the entrance of the grouting pipe close to the grouting hole.

[0009] Furthermore, in step 5), the precise measuring instruments include a total station and a level, the drilling spacing includes a deep drilling spacing and a shallow drilling spacing, and the drilling spacing is determined according to the actual situation of the roadbed to ensure that the grouting effect evenly covers the entire reinforcement area.

[0010] Furthermore, the step 6) and the step 7) also include a hole cleaning step, where the grouting pipe is connected to the bottom of the deep borehole, and clean water is injected to clean the borehole before grouting to flush out debris, soil and other impurities in the hole.

[0011] Furthermore, in the step 8), the quality control includes related contents of material quality control, grouting process monitoring, grouting volume control and personnel management.

[0012] Furthermore, in step 9), the non-destructive testing method uses geological radar to detect the internal structure of the roadbed soil after grouting reinforcement, and uses the sound wave transmission method to detect the grouting effect.

[0013] Furthermore, it also includes the steps of construction safety and environmental protection. The construction safety includes personnel safety education, equipment safe operation education, on-site safety protection measures, and the formulation and drills of emergency plans; the environmental protection includes material management, waste disposal and noise control.

[0014] Advantages of the invention: The invention provides a layered grouting reinforcement method for roadbed, which realizes targeted reinforcement of soil layers at different depths through precise geological survey and layered grouting design, and effectively improves the overall bearing capacity and stability of the roadbed. This method has a short construction period and little impact on traffic, and the grouting materials can be recycled, which reduces the project cost and conforms to the concept of green construction. At the same time, the use of high-precision grouting equipment and intelligent monitoring technology ensures the precise control of the grouting process, improves the reinforcement effect and quality reliability. In addition, this method also focuses on construction safety and environmental protection, and provides a strong guarantee for the sustainable development of roadbed reinforcement projects. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 The present invention discloses a flow chart of a roadbed layered grouting reinforcement method. DETAILED DESCRIPTION

[0016] The technical solution of the present invention is not limited to the specific implementation modes listed below, but also includes any reasonable combination of the specific implementation modes.

[0017] A roadbed layered grouting reinforcement method comprises the following steps:

[0018] 1) Geological survey: Use professional geological exploration equipment and technology to conduct a comprehensive survey of the soil structure within the roadbed to clarify the distribution of soil layers at different depths. Specifically, the comprehensive survey of the soil structure within the roadbed includes information on the thickness, type, density, groundwater level depth and changes of each soil layer, and draw an accurate geological profile based on the survey results to clarify the distribution of soil layers at different depths, providing an accurate basis for subsequent layered grouting design.

[0019] 2) Material selection and proportion: Cement is used as the main grouting material, and admixtures are added according to the characteristics of different soil layers. Specifically, the admixtures include early strength agent, expansion agent, and fiber admixture. For deep soil, an appropriate amount of early strength agent is added. Considering the high pressure of deep soil, expansion agent is added to compensate for the shrinkage of the grouting material during the hardening process; for shallow soil, in order to enhance its flexibility and crack resistance, the cement content in the grouting material is reduced and some fiber admixtures are added.

[0020] 3) Equipment preparation: prepare a high-precision grouting pump with the function of accurately adjusting the grouting pressure and flow, a grouting pipe with adjustable length and diameter, and install intelligent pressure sensors and flow monitors. Specifically, the high-precision grouting pump has the function of accurately adjusting the grouting pressure and flow. The pressure adjustment range can meet the grouting requirements of soil layers of different depths. The flow control accuracy is high to ensure the stability and uniformity of the grouting process. Intelligent pressure sensors are installed at the outlet of the grouting pump and the bottom of the grouting hole. At the same time, they are set at intervals along the grouting pipe. The flow monitor is installed at the outlet of the grouting pump and at the entrance of the grouting pipe close to the grouting hole. The sensor can collect grouting pressure data in real time and accurately and transmit it to the monitoring system. The flow monitor can accurately measure the flow changes during the grouting process and provide real-time data feedback for the grouting operation so as to adjust the grouting parameters in time.

[0021] 4) Site planning and traffic diversion: Rationally plan the construction site around the roadbed, formulate a detailed traffic diversion plan, reduce the impact of construction on road traffic, and ensure the safe passage of vehicles and pedestrians. Specifically, reasonably plan the construction site around the roadbed, set up a special material storage area, classify and store different types of grouting materials, and take moisture-proof and rain-proof measures. Set up an equipment parking area to ensure the orderly parking and daily maintenance of grouting equipment. Plan the grouting work area to ensure that each drilling and grouting operation point has sufficient operating space and does not interfere with each other.

[0022] 5) Drilling positioning: The drilling spacing is determined according to the degree of roadbed damage and soil characteristics, and the drilling positions are accurately marked on the roadbed surface using measuring instruments. Specifically, the precise measuring instruments include total stations and levels, and the drilling spacing includes deep drilling spacing and shallow drilling spacing. The drilling spacing is determined according to the actual situation of the roadbed to ensure that the grouting effect evenly covers the entire reinforcement area.

[0023] 6) Deep grouting: Connect the grouting pipe to the bottom of the deep borehole, and start the grouting operation after fully stirring the deep grouting material in the grouting pump according to the predetermined ratio. Specifically, connect the grouting pipe to the bottom of the deep borehole, and inject clean water to clean the borehole before grouting, and rinse the debris, soil and other impurities in the hole to ensure that the grouting channel is unobstructed. According to the predetermined ratio of deep grouting materials, start the grouting operation after fully stirring in the grouting pump. The initial grouting pressure is set at 0.5-1.0MPa, and then the pressure is gradually increased at a certain rate according to the real-time monitoring data of the intelligent pressure sensor, but the maximum pressure must not exceed the design maximum pressure value (such as 3-5MPa) to prevent soil splitting and damage due to excessive pressure, which affects the grouting effect. The grouting flow rate and grouting volume are monitored in real time through the flow monitor. When the grouting pressure reaches the design value and the grouting volume is stable within a certain range (determined according to the design calculation and field test), the grouting is suspended and observed for a period of time (such as 10-15 minutes). If the pressure does not drop significantly, it indicates that the deep grouting of the hole is initially completed and the next step can be carried out. If the pressure drops significantly, it is necessary to analyze the reasons, such as whether there is a leakage channel, etc., and take corresponding measures (such as supplementary injection, plugging leakage points, etc.) and continue grouting until the requirements are met.

[0024] 7) Shallow grouting: After the deep grouting is completed and reaches a certain strength, the shallow drilling grouting operation is carried out, and the shallow grouting material is prepared according to the previously determined proportion suitable for the shallow soil. Specifically, after the deep grouting is completed and reaches a certain strength, the shallow drilling grouting operation is carried out, and the shallow grouting material is prepared according to the previously determined proportion suitable for the shallow soil. Similarly, the shallow borehole is cleaned first, and then the grouting pipe is connected to start grouting. Since the shallow soil is relatively loose, the grouting pressure control is relatively low. The initial pressure can be set at 0.3-0.5MPa, and the intermittent grouting method is adopted, that is, after grouting for a period of time (such as 5-10 minutes), it is paused for 3-5 minutes, and the grouting material is fully infiltrated and diffused in the soil before continuing the grouting, and this is repeated. This can avoid soil uplift or slurry loss caused by injecting too much slurry at one time. During the shallow grouting process, a special person is arranged to monitor the roadbed surface in real time to observe whether there are abnormal phenomena such as uplift and cracking. If it is found that the roadbed surface bulge exceeds a certain limit (such as 5-10 mm), the grouting pressure should be reduced or the grouting should be suspended in time. The cause should be analyzed and the grouting parameters should be adjusted (such as reducing the grouting volume, adjusting the grouting speed, etc.) before continuing the construction to ensure that the shallow grouting can effectively reinforce the soil without causing adverse effects on the roadbed surface.

[0025] 8) Quality control: quality inspection of incoming raw materials, strict monitoring of the operation of grouting equipment during grouting, detailed record of grouting volume of grouting holes, and professional training of on-site operators. Specifically, the quality control includes material quality control, grouting process monitoring, grouting volume control and personnel management.

[0026] 9) Quality inspection: Use non-destructive testing methods to detect the internal structure of the roadbed soil after grouting reinforcement. Specifically, use geological radar to detect the internal structure of the roadbed soil after grouting reinforcement. Geological radar generates images of the inside of the roadbed soil by emitting high-frequency electromagnetic waves and based on the reflection characteristics of electromagnetic waves in different media, so as to determine whether the grouting effect is uniform and whether the soil density meets the design requirements. At the same time, the sound wave transmission method can be used to pre-embed sound wave transducers in the roadbed. By measuring the propagation speed, amplitude and other parameters of the sound waves in the grouting reinforced soil, the strength and uniformity changes of the soil can be analyzed to detect the grouting effect.

[0027] 10) Settlement observation: Settle settlement observation points on the roadbed surface, and conduct settlement observations regularly before grouting construction, during construction and during road operation.

[0028] Furthermore, it also includes the steps of construction safety and environmental protection. The construction safety includes personnel safety education, equipment safe operation education, on-site safety protection measures, and the formulation and drills of emergency plans; the environmental protection includes material management, waste disposal and noise control.

[0029] The present invention and its embodiments are described above, and such description is not restrictive. The drawings show only one embodiment of the present invention, and the actual structure is not limited thereto. In short, if ordinary technicians in the field are inspired by it, without departing from the purpose of the invention, they can design a structure and embodiment similar to the technical solution without creativity, which should belong to the protection scope of the present invention.

Claims

1. A roadbed layered grouting reinforcement method, characterized in that: The following steps are involved: 1) Geological survey: Use professional geological exploration equipment and technology to conduct a comprehensive survey of the soil structure within the roadbed range to clarify the distribution of soil layers at different depths; 2) Material selection and proportion: Cement is used as the main grouting material, and admixtures are added according to the characteristics of different soil layers; 3) Equipment preparation: prepare a high-precision grouting pump with the function of accurately adjusting the grouting pressure and flow rate, equip a grouting pipe with adjustable length and diameter, and install an intelligent pressure sensor and flow monitor; 4) Site planning and traffic diversion: Rationally plan the construction site around the roadbed and formulate a detailed traffic diversion plan to reduce the impact of construction on road traffic and ensure the safe passage of vehicles and pedestrians; 5) Drilling positioning: Determine the drilling spacing according to the degree of roadbed damage and soil characteristics, and use measuring instruments to accurately mark the drilling positions on the roadbed surface; 6) Deep grouting: Connect the grouting pipe to the bottom of the deep borehole, and start the grouting operation after fully stirring the deep grouting material in the grouting pump according to the predetermined ratio of the deep grouting material; 7) Shallow grouting: After the deep grouting is completed and reaches a certain strength, shallow drilling grouting is carried out. The shallow grouting material is prepared according to the previously determined proportion suitable for the shallow soil; 8) Quality control: conduct quality inspection on incoming raw materials, strictly monitor the operation of grouting equipment during grouting, record the grouting volume of grouting holes in detail, and provide professional training for on-site operators; 9) Quality inspection: Use non-destructive testing methods to inspect the internal structure of the roadbed soil after grouting reinforcement; 10) Settlement observation: Settle settlement observation points on the roadbed surface, and conduct settlement observations regularly before grouting construction, during construction and during road operation.

2. A roadbed layered grouting reinforcement method according to claim 1, characterized in that: In the step 1), the soil layer structure within the roadbed is comprehensively detected, including information on the thickness, type, density, groundwater level depth and changes of each soil layer, and an accurate geological profile is drawn based on the detection results to clarify the distribution of soil layers at different depths, providing an accurate basis for subsequent layered grouting design.

3. A roadbed layered grouting reinforcement method according to claim 1, characterized in that: In the step 2), the admixtures include an early strength agent, an expansive agent, and a fiber admixture. For deep soil, a proper amount of early strength agent is added. Considering that the pressure of the deep soil is relatively large, an expansive agent is added to compensate for the shrinkage of the grouting material during the hardening process. For shallow soil, in order to enhance its flexibility and crack resistance, the cement content in the grouting material is reduced and some fiber admixtures are added.

4. A roadbed layered grouting reinforcement method according to claim 1, characterized in that: In the step 3), the intelligent pressure sensor is installed at the outlet of the grouting pump and at the bottom of the grouting hole, and is arranged at intervals along the grouting pipe; the flow monitor is installed at the outlet of the grouting pump and at the entrance of the grouting pipe close to the grouting hole.

5. A roadbed layered grouting reinforcement method according to claim 1, characterized in that: In the step 5), the precise measuring instruments include a total station and a level, the drilling spacing includes a deep drilling spacing and a shallow drilling spacing, and the drilling spacing is determined according to the actual situation of the roadbed to ensure that the grouting effect evenly covers the entire reinforcement area.

6. A roadbed layered grouting reinforcement method according to claim 1, characterized in that: The steps 6) and 7) also include a hole cleaning step, where a grouting pipe is connected to the bottom of the deep borehole, and clean water is injected to clean the borehole before grouting to flush out debris, soil and other impurities in the hole.

7. A roadbed layered grouting reinforcement method according to claim 1, characterized in that: In the step 8), the quality control includes material quality control, grouting process monitoring, grouting volume control and personnel management.

8. A roadbed layered grouting reinforcement method according to claim 1, characterized in that: In the step 9), the non-destructive testing method uses geological radar to detect the internal structure of the roadbed soil after grouting reinforcement, and uses the sound wave transmission method to detect the grouting effect.

9. A roadbed layered grouting reinforcement method according to any one of claims 1 to 8, characterized in that: It also includes steps for construction safety and environmental protection. The construction safety includes personnel safety education, equipment safety operation education, on-site safety protection measures, and the formulation and drills of emergency plans; the environmental protection includes material management, waste disposal and noise control.

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