Building foundation construction method under complex geological conditions

Abstract

The invention relates to the technical field of foundation construction, and provides a building foundation construction method under complex geological conditions. The method comprises the following steps: S1, sampling and detecting land by using equipment, and comprehensively analyzing soil layer, underground water level and geological risk; s2, a foundation pit geometrical shape and a supporting scheme are designed according to an exploration result, and construction safety is ensured; s3, an underground descending well is set up to lower the underground water level of the construction area; s4, a deep mixing pile is adopted for foundation reinforcement, and the bearing capacity of a soil body is improved; s5, the soil body is improved, and the soil strength and stability are improved; and S6, the foundation pit is monitored in real time, and the displacement, the underground water level and the soil pressure of the foundation pit are monitored. By adopting an advanced geological detection technology, the properties of underground soil and rocks can be accurately evaluated before construction, and the measure can find potential geological hidden dangers in time, so that corresponding safety measures are formulated, the risk in the construction process is reduced, and the safety of constructors is ensured.

Description

Technical Field

[0001] The invention relates to the technical field of foundation construction, in particular to a building foundation construction method under complex geological conditions. Background Art

[0002] In modern construction projects, the stability and safety of the foundation are directly related to the overall performance of the building, especially under complex geological conditions. Complex geological conditions usually include variable soil layers, rocks, groundwater, etc. These factors bring many challenges to foundation construction. Traditional foundation construction methods are often unable to effectively deal with these complex factors, which can easily lead to construction delays, increased costs, and even affect the safety of the building.

[0003] Traditional foundation construction methods are usually based on experience, lack of specificity, and easily ignore the impact of specific geological conditions, leading to unexpected engineering accidents and foundation settlement. In addition, with the acceleration of urbanization, construction projects are increasingly concentrated in densely populated urban areas, which makes the impact of complex geological conditions more prominent.

[0004] Therefore, the present invention proposes a building foundation construction method under complex geological conditions. Summary of the invention

[0005] In view of the deficiencies in the prior art, the present invention provides a method for constructing building foundations under complex geological conditions, which solves the problem of insufficient stability and safety during foundation construction under complex geological conditions.

[0006] To achieve the above objectives, the present invention is implemented through the following technical solutions: A construction method for building foundation under complex geological conditions, comprising the following steps;

[0007] S1. Use equipment to sample and test the land, and comprehensively analyze the soil layers, groundwater levels and geological risks;

[0008] S2. Design the foundation pit geometry and support scheme based on the exploration results to ensure construction safety;

[0009] S3. Establish underground drainage wells to lower the groundwater level in the construction area;

[0010] S4. Use deep mixing piles to reinforce the foundation and improve the bearing capacity of the soil;

[0011] S5. Improve the soil to enhance its strength and stability;

[0012] S6. Real-time monitoring of foundation pit, including displacement, groundwater level and soil pressure;

[0013] S7. Carry out construction in stages, ensuring quality inspection and safety assessment at each stage;

[0014] S8. After acceptance, implement layered backfilling to ensure the compactness of the fill.

[0015] Preferably, the step S1 includes the following specific steps:

[0016] S1.1. Select appropriate equipment for soil sampling and testing, including rotary drilling machines, standard penetration testers and electromagnetic detectors;

[0017] S1.2. Set up multiple drilling points in the construction area and drill the soil layers at predetermined intervals with a drilling depth of no less than 30m to obtain the physical and mechanical properties of each soil layer;

[0018] S1.3. Conduct laboratory tests on the collected soil samples to determine the density, moisture content, friction angle and cohesion of the soil layer;

[0019] S1.4. Use electromagnetic detection and seismic reflection methods for non-destructive testing to identify groundwater levels, soil layer distribution and potential geological risks, and record groundwater level changes and their impact on soil stability;

[0020] S1.5. Comprehensively analyze the data obtained above to evaluate the soil characteristics, groundwater level changes and potential geological risks in the construction area.

[0021] Preferably, the slope angle of the foundation pit in step S2 is 30°-45° to ensure the stability of the slope.

[0022] Preferably, in the groundwater management system in step S3, the spacing between the precipitation wells is 8m-15m, and the pumping flow rate is set to keep the water level lowered.

[0023] Preferably, the step S4 includes the following specific steps:

[0024] S4.1. Select appropriate deep mixing equipment and calibrate the position of each mixing pile to ensure the verticality and position of the pile are accurate;

[0025] S4.2. The diameter of the deep mixing pile should be controlled to be 600mm-700mm, and the mixing depth should be 4.5m-6m;

[0026] S4.3. During the construction of the mixing pile, cement slurry is mixed with the soil in a ratio of 1:8 to ensure full mixing to form the pile body;

[0027] S4.4. During the mixing process, monitor the fluidity of the cement slurry to ensure that the slurry fully penetrates into the soil, and record the injection pressure of the slurry. The pressure should be controlled at 0.8-1.2MPa.

[0028] Preferably, the soil improvement method in step S5 is grouting soil consolidation and biological soil consolidation.

[0029] Preferably, the grouting soil consolidation is performed by injecting cement slurry, and the ratio of cement to water in the slurry is 1:1.5.

[0030] Preferably, the biological soil-fixing material is a microbial agent or a plant root promoter, and the addition ratio is 1%-5% of the soil mass.

[0031] Preferably, in step S6, real-time monitoring is performed by using a level meter, a displacement sensor and a mixed multi-stage water level gauge, which is set at the slope and bottom of the foundation pit to obtain displacement data and water level changes in real time.

[0032] Preferably, the backfill materials in step S8 include sand, gravel, soil and mixed materials. When backfilling in layers, the thickness of each backfill layer is controlled within 30cm-40cm, and mechanical compaction is used to ensure the density and stability of the backfill.

[0033] The present invention provides a construction method for building foundation under complex geological conditions. It has the following beneficial effects:

[0034] 1. The present invention uses advanced geological detection technology to accurately evaluate the properties of underground soil and rocks before construction. This measure can timely discover potential geological hazards, thereby formulating corresponding safety measures, reducing risks during the construction process, and ensuring the safety of construction workers.

[0035] 2. The present invention can effectively enhance the stability of the foundation through specific treatment methods for complex geological conditions, such as deep foundation pit support and groundwater control. This treatment method not only improves the compressive strength of the building, but also reduces the risk of settlement, ensuring the long-term safety of the building. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] Figure 1 The figure is a flow chart of the method of the present invention. DETAILED DESCRIPTION

[0037] The following will be combined with the drawings in the specification of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0038] Please see attached Figure 1 , an embodiment of the present invention provides a method for constructing a building foundation under complex geological conditions, comprising the following steps;

[0039] S1. Use equipment to sample and test the land, and comprehensively analyze the soil layers, groundwater levels and geological risks;

[0040] Specifically, high-efficiency testing equipment is selected, such as rotary drilling machines, standard penetration testers, dynamic and static penetration testers, seismic reflectometers and electromagnetic detectors. Multiple drilling points are set in the construction area. The drilling spacing is optimized according to the changes in the soil layer, usually 5m-10m; multiple drilling points are set in the construction area, and soil layers are drilled at predetermined intervals with a drilling depth of 25m-35m to obtain the physical and mechanical properties of each soil layer. The collected soil samples are tested for physical and mechanical properties such as density, moisture content, friction angle, cohesion, etc. to evaluate the bearing capacity and stability of the soil layer. The electromagnetic detection method and seismic reflection method are used to identify the groundwater level and potential geological risks, record the changes in the groundwater level and its impact on the stability of the soil, and provide data support for subsequent analysis.

[0041] S2. Design the foundation pit geometry and support scheme based on the exploration results to ensure construction safety;

[0042] Specifically, according to the soil characteristics and design requirements, the foundation pit slope angle is determined to be 30° to 45°. According to the designed slope angle and soil characteristics, a suitable support method is selected, including but not limited to concrete support, anchor support and steel support system, to ensure that the structure can withstand soil pressure and water pressure;

[0043] S3. Establish underground drainage wells to lower the groundwater level in the construction area;

[0044] Specifically, according to the geological exploration results, precipitation wells are set up in the construction area with a spacing of 10m to 15m to ensure effective drainage. Flow monitoring devices are installed to monitor the pumping flow and groundwater level changes in real time. An automated control system is used to dynamically adjust the pumping volume to keep the water level within a safe range. The water pumped out of the precipitation wells is regularly tested for quality to ensure that the water quality during the construction process meets environmental protection requirements. Through effective groundwater management, the buoyancy of groundwater on the soil is reduced, the bearing capacity of the soil is improved, and construction risks are reduced.

[0045] S4. Use deep mixing piles to reinforce the foundation and improve the bearing capacity of the soil;

[0046] Specifically, calibration is performed before construction to ensure the verticality and position of the piles are accurate. The diameter of the deep mixing pile is set to 600mm, the mixing depth reaches 5m, and cement slurry is mixed with soil at a ratio of 1:8. According to the soil characteristics, the ratio of cement slurry is adjusted to improve the mixing effect. During the mixing process, a pressure sensor is used to monitor the injection pressure of the cement slurry and keep it between 0.8MPa and 1.2MPa to ensure that the slurry fully penetrates the soil. During the mixing process, samples are taken regularly to test the strength and uniformity of the mixed soil to ensure the construction quality;

[0047] S5. Improve the soil to enhance its strength and stability;

[0048] Specifically, cement slurry is injected into the soil through grouting equipment, and the ratio of cement to water in the slurry is 1:1.5, so that the slurry is evenly distributed in the soil. By observing the pressure change during the grouting process, it is judged whether the slurry is fully penetrated, and the injection amount of the slurry is recorded to evaluate the improvement effect. The appropriate bio-soil-fixing material is selected to be added in a ratio of 1% to 5% of the mass of the soil. The bio-soil-fixing material is evenly spread on the surface of the soil, and then stirred to fully mix the bio-material with the soil.

[0049] S6. Real-time monitoring of foundation pit, including displacement, groundwater level and soil pressure;

[0050] Specifically, level gauges, displacement sensors and multi-level water level gauges are arranged on the slope and bottom of the foundation pit to obtain displacement and water level change data in real time to ensure timely discovery of potential problems. Monitoring data are recorded regularly and analyzed in real time through data analysis software to detect abnormal situations in a timely manner and respond quickly. An alarm mechanism is set up. When the monitoring data exceeds the safety range, an alarm is automatically issued and relevant personnel are notified so that response measures can be taken quickly to prevent accidents. Real-time monitoring provides timely feedback on the status of the foundation pit, ensures the safety of the construction process, reduces the occurrence of accidents, and effectively protects the safety of construction personnel and equipment.

[0051] S7. Carry out construction in stages, ensuring quality inspection and safety assessment at each stage;

[0052] Specifically, the construction process is divided into multiple stages, and detailed construction plans and quality control standards are formulated for each stage to ensure that the construction process proceeds in an orderly manner. After each stage, quality inspections are carried out, including soil strength testing, foundation pit stability assessment, etc., to ensure that the construction meets the predetermined standards and a written report is formed. According to the quality inspection results, the construction plan is adjusted in a timely manner to ensure that the construction quality of each stage meets the standards and reduces potential risks. The phased construction method effectively reduces construction risks, improves the flexibility and efficiency of construction management, ensures project quality, and reduces later maintenance costs;

[0053] S8. After acceptance, backfill in layers to ensure the compactness of the fill;

[0054] Specifically, select backfill materials that meet the standards, including sand, gravel and mixed materials, to ensure that their physical properties meet the construction requirements. The thickness of each backfill layer is controlled within 30cm-40cm, and mechanical compaction is used to ensure the density of the fill. At the same time, the density of each backfill layer is tested after density testing, and each layer of fill is tested for density to ensure that the fill meets the predetermined density standards.

[0055] Embodiment 1:

[0056] This embodiment discloses a method for constructing a building foundation under coastal geological conditions;

[0057] Solve the problem of unstable foundation caused by geological complexity and high groundwater level in coastal areas. Through systematic soil sampling and testing, the bearing capacity of the soil layer can be accurately evaluated to ensure that the foundation pit design is in line with the actual situation. The application of deep mixing pile technology improves the bearing capacity of the foundation;

[0058] A building foundation construction method under complex geological conditions, characterized by comprising the following steps:

[0059] S1. Use equipment to sample and test the land, and comprehensively analyze the soil layers, groundwater levels and geological risks;

[0060] Multiple drilling points were set up in the construction area, with an optimized spacing of 5m and a drilling depth of 40m to obtain the physical and mechanical properties of each soil layer. Laboratory tests on soil samples were conducted, including density, moisture content, friction angle and cohesion, and the changes in groundwater levels were recorded to analyze the impact of seawater intrusion on soil stability.

[0061] S2. Design the foundation pit geometry and support scheme based on the exploration results to ensure construction safety;

[0062] According to the exploration results, the slope angle of the foundation pit was determined to be 30°, and concrete support was selected to cope with tidal changes and soil pressure.

[0063] S3. Establish underground drainage wells to lower the groundwater level in the construction area;

[0064] Set up dewatering wells with a spacing of 10m and configure flow monitoring devices to monitor the pumping flow and groundwater level changes in real time. Use an automated control system to dynamically adjust the pumping volume to ensure the stability of the groundwater level and reduce construction risks.

[0065] S4. Use deep mixing piles to reinforce the foundation and improve the bearing capacity of the soil;

[0066] The diameter of the deep mixing pile is set to 700mm and the depth is 5m to adapt to the soil characteristics of coastal areas. During the construction process, cement slurry is prepared with a cement to soil ratio of 1:8 to ensure that the slurry can fully penetrate into the soil. During the preparation process, pay attention to the type and characteristics of cement to adapt to the requirements of the humid environment. Use a pressure sensor to monitor the slurry injection pressure in real time and maintain it at 0.8MPa to ensure uniform penetration of the slurry. Adjust the injection speed to ensure that the slurry can effectively fill the voids in the soil. During the mixing process, regularly conduct sampling tests on the strength and uniformity of the pile to ensure that the quality of the pile meets the design requirements. Record the flow of the slurry during the mixing process;

[0067] S5. Improve the soil to enhance its strength and stability;

[0068] First, use grouting equipment to inject cement slurry into the soil. The ratio of cement to water in the slurry is 1:1.5 to ensure that the slurry has good viscosity and fluidity for easy penetration. During the grouting process, the grouting pressure is monitored in real time and maintained at 1MPa to ensure that the slurry can fully penetrate into all layers of the soil. According to the characteristics of the soil, especially in high-salt environments, an appropriate amount of admixture is added to improve the soil's impermeability and strength. Microbial agents are selected as biological soil-solidifying materials and evenly spread on the soil surface at a ratio of 1%-5% of the soil mass. They are fully stirred and mixed with the soil. These biological materials can promote the combination of soil particles and improve the soil's resistance to erosion and bearing capacity. After a certain period of maintenance, observe the soil improvement effect and conduct strength tests regularly;

[0069] S6. Real-time monitoring of foundation pit, including displacement, groundwater level and soil pressure;

[0070] Level gauges, displacement sensors and multi-level water level gauges are installed on the slope and bottom of the foundation pit to obtain displacement and water level data in real time. The data is analyzed by the monitoring system to detect potential problems and alarm in time. The alarm mechanism is set up to automatically issue an alarm and notify relevant personnel when the monitoring data exceeds the safety range;

[0071] S7. Carry out construction in stages, ensuring quality inspection and safety assessment at each stage;

[0072] The construction is divided into multiple stages, and detailed plans and quality control are made for each stage to ensure the orderly progress of the construction. After each stage, a comprehensive quality inspection is carried out, a written report is formed, and the construction plan is adjusted in a timely manner according to the results.

[0073] S8. After acceptance, backfill in layers to ensure the compactness of the fill;

[0074] Select backfill materials that meet the standards, including sand and gravel. During the layered backfilling process, the thickness of each layer is controlled within 30cm to ensure the uniformity and stability of the backfill. Use mechanical compaction equipment to compact each layer of backfill, and the compaction degree should reach more than 98% to prevent later settlement and displacement. After each layer of backfilling, conduct density testing, and regularly monitor soil moisture during the backfilling process to ensure that the soil maintains appropriate humidity and promote good combination of soil and backfill materials.

[0075] Summarize

[0076] The safety and effectiveness of the construction were ensured through systematic soil sampling and testing, foundation pit design, precipitation control, deep mixing pile reinforcement and real-time monitoring. During the implementation process, a comprehensive assessment of the bearing capacity and stability of the soil layer was conducted, providing solid data support for the design. In the end, the project was successfully completed within the specified time and met the building regulations and safety standards, significantly reducing the construction risks caused by geological conditions.

[0077] Embodiment 2:

[0078] This embodiment discloses a method for constructing a building foundation under mountainous geological conditions;

[0079] Solving the special geological conditions of mountain landslide areas aims to improve the stability and safety of the foundation. Through accurate soil testing and risk assessment, the potential threat of landslides can be discovered in time. The use of deep mixing piles and soil improvement technology enhances the strength of the soil and reduces the risk of landslides.

[0080] S1. Use equipment to sample and test the land, and comprehensively analyze the soil layers, groundwater levels and geological risks;

[0081] Use rotary drilling machines and standard penetration testers to accurately obtain soil samples. According to the terrain and geological characteristics, set multiple drilling points in the construction area, usually with a spacing of 10m and a depth of up to 30m, focusing on potential landslide areas. During the drilling process, extract soil samples in layers to ensure that soil samples at different layers are collected and sealed with special material containers to maintain the original state of the samples. Conduct laboratory tests on the collected soil samples to measure the density, moisture content, plasticity index and permeability of the soil layer to evaluate the strength and stability of the soil. Use seismic reflection method and electromagnetic detection method to determine the distribution of soil layers and their physical properties in the landslide area and identify potential landslide risks;

[0082] S2. Design the foundation pit geometry and support scheme based on the exploration results to ensure construction safety;

[0083] The geometric shape of the foundation pit is designed according to the characteristics of the soil layer, the slope angle is set to 35°, and a steel support structure is used to ensure that it can withstand the pressure of the landslide soil;

[0084] S3. Establish underground drainage wells to lower the groundwater level in the construction area;

[0085] Set up drainage wells with a spacing of 8m to ensure effective drainage and lower the groundwater level. Configure a real-time monitoring system to dynamically adjust the pumping flow to prevent the impact of rising water levels caused by the rainy season on construction;

[0086] S4. Use deep mixing piles to reinforce the foundation and improve the bearing capacity of the soil;

[0087] Combined with geological exploration data, key locations are selected for deep mixing. The diameter of the deep mixing pile is 600mm, and the depth can be adjusted according to the actual soil conditions to ensure that the pile body can penetrate the unstable layer and reach the stable layer. Modified cement slurry is used for mixing with a ratio of 1:6 to increase the compressive strength of cement, and an appropriate amount of admixture is added to improve the fluidity and adhesion of the slurry. During the construction process, the injection pressure of the slurry is monitored to ensure that it is within the range of 1.5MPa to improve the penetration effect of the slurry. The mixing speed is adjusted in time to adapt to soil changes. Each mixing pile is sampled and tested to check the uniformity and strength of the pile body to ensure that the pile body can withstand the design load;

[0088] S5. Improve the soil to enhance its strength and stability;

[0089] In mountainous areas with a high risk of landslides, soil improvement adopts grouting to consolidate the soil. The grouting material is modified cement slurry, and the ratio of cement to water is 1:1.5. Before grouting, the landslide soil is first analyzed in detail to determine the optimal grouting depth and position. During the grouting process, high-pressure grouting equipment is used to ensure that the slurry can quickly fill the soil cracks and voids during the injection process. The grouting pressure is monitored in real time and maintained between 1.3MPa to ensure uniform penetration of the slurry. Plant root promoters are used as biological soil-fixing materials, and the addition ratio is 2% to 3% of the soil mass. This material can promote plant growth and enhance the cohesion and structural stability of the soil. In the later stage of construction, the strength changes of the soil are regularly monitored, and the effect of soil improvement is evaluated through dynamic testing to ensure that the risk of landslides is effectively reduced and the stability of the foundation is guaranteed;

[0090] S6. Real-time monitoring of foundation pit, including displacement, groundwater level and soil pressure;

[0091] High-precision levels, displacement sensors and strain gauges are installed at key locations, such as landslide risk areas and foundation pit slopes. Monitoring sensors are arranged at different depths to obtain multi-level soil displacement and pressure data to help identify potential landslide risks;

[0092] S7. Carry out construction in stages, ensuring quality inspection and safety assessment at each stage;

[0093] During the construction process, soil strength and foundation pit stability inspections are immediately carried out after each stage is completed to ensure that the construction standards are met, and necessary adjustments are made based on the inspection results;

[0094] S8. After acceptance, backfill in layers to ensure the compactness of the fill;

[0095] Use stable sand and gravel, and avoid using materials that are easy to flow. The backfill process is carried out in layers, and the thickness of each layer is controlled within 20cm to ensure the uniformity and stability of each layer. Use heavy rollers to compact each layer to ensure that the density of the backfill reaches more than 98% to reduce the risk of future settlement. After each layer of backfill is completed, use a soil density tester to test it to ensure that the density of the backfill meets the design standards;

[0096] Summarize;

[0097] By using deep mixing pile technology and soil improvement methods, the bearing capacity and stability of the soil were improved, effectively responding to the potential threat of landslides, thereby successfully completing the foundation construction and ensuring the safety of subsequent construction.

[0098] Embodiment three:

[0099] This embodiment discloses a method for constructing a building foundation under geological conditions in a mining area;

[0100] Solve the construction safety problems caused by geological instability near the mining area, identify geological risks in time and take appropriate construction measures. The combination of deep mixing piles and soil improvement improves the bearing capacity and stability of the soil and reduces the risks during construction.

[0101] S1. Use equipment to sample and test the land, and comprehensively analyze the soil layers, groundwater levels and geological risks;

[0102] Use rotary drills, standard penetration testers and dynamic penetration instruments to obtain multi-layer soil samples. Set up multiple drilling points around the mining area to ensure coverage of potential impact areas. Usually, the drilling depth is set to 25m. Soil samples are collected in layers, focusing on the layers containing minerals to ensure the accuracy and representativeness of the samples. Sealed containers are used to prevent sample contamination. Soil density, moisture content, permeability and heavy metal content are tested to evaluate the safety and bearing capacity of the soil. Through seismic reflection and electromagnetic detection methods, the distribution of underground soil layers and their physical properties are analyzed to evaluate potential geological risks.

[0103] S2. Design the foundation pit geometry and support scheme based on the exploration results to ensure construction safety;

[0104] Design the foundation pit geometry, control the slope angle at 30°, and select appropriate concrete supports to ensure stability against heavy metal corrosion;

[0105] S3. Establish underground drainage wells to lower the groundwater level in the construction area;

[0106] Set up drainage wells with a spacing of 15m, use flow monitoring devices to monitor groundwater levels in real time, ensure that water quality in the construction area meets standards, and reduce the impact of heavy metals on the soil;

[0107] S4. Use deep mixing piles to reinforce the foundation and improve the bearing capacity of the soil;

[0108] According to the soil characteristics of the mining area, the pile position is accurately calibrated to ensure the accuracy of each mixing pile. The diameter is 600mm and the depth is 5m. The pile body is ensured to penetrate the loose layer around the mining area and stabilize in the hard soil layer. Environmentally friendly cement slurry is used with a ratio of 1:8 to ensure that it does not cause pollution to the environment and improve the strength of the soil. When injecting the slurry, the injection pressure is maintained at 1.2MPa to ensure that the slurry can quickly fill the soil voids and make timely adjustments. By real-time monitoring of the mixing process, the uniformity and strength of the pile body are regularly checked to ensure that the design standards are met;

[0109] S5. Improve the soil to enhance its strength and stability;

[0110] Use modified cement slurry for grouting, with a cement-water ratio of 1:1.5 to enhance the stability of the soil, ensure that the slurry can penetrate the entire soil and enhance its bearing capacity. Use plant root promoters at a ratio of 2%-4% of the soil mass. This material can promote the growth of plant roots, thereby enhancing the structural stability of the soil. During the construction process, monitor the soil improvement effect, regularly evaluate the soil strength through sampling and testing methods to ensure that it meets the design standards, and adjust the plan in time in subsequent construction to maintain the long-term stability of the soil;

[0111] S6. Real-time monitoring of foundation pit, including displacement, groundwater level and soil pressure;

[0112] Install highly sensitive displacement sensors, soil pressure gauges and water level monitoring equipment to ensure that they can capture tiny changes, use machine learning algorithms to analyze monitoring data, automatically identify abnormal situations, reduce manual intervention, and improve response speed. Set early warning levels based on monitoring data, formulate emergency plans, and immediately initiate emergency measures when monitoring data reaches the alarm threshold;

[0113] S7. Carry out construction in stages, ensuring quality inspection and safety assessment at each stage;

[0114] The construction is divided into four stages: geological exploration, foundation pit excavation, foundation reinforcement, and environmental restoration. During the construction process, regular monitoring is carried out, and the construction plan is adjusted according to the data results to ensure construction safety. Environmental protection measures are implemented during construction to reduce the impact on the surrounding environment, and water quality testing is carried out regularly;

[0115] S8. After acceptance, backfill in layers to ensure the compactness of the fill;

[0116] Summarize;

[0117] Through comprehensive soil testing and pollution assessment, potential geological risks were successfully identified. The construction team implemented deep mixing piles and soil improvement to improve the strength and stability of the soil, effectively preventing potential safety hazards during the construction process.

[0118] Treated sand and gravel to avoid the impact of heavy metals and other pollutants on the environment. The backfill process is carried out in layers, and the thickness of each layer is controlled at 30cm. Use mechanical compaction equipment to compact each layer of fill to ensure that the density of the fill reaches more than 98% to avoid later settlement. After each layer is completed, use a nuclear density meter to test the density to ensure that the compaction quality of each layer meets the requirements. During the backfill process.

[0119] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A building foundation construction method under complex geological conditions, characterized in that: The steps include: S1. Use equipment to sample and test the land, and comprehensively analyze the soil layers, groundwater levels and geological risks; S2. Design the foundation pit geometry and support scheme based on the exploration results to ensure construction safety; S3. Establish underground drainage wells to lower the groundwater level in the construction area; S4. Use deep mixing piles to reinforce the foundation and improve the bearing capacity of the soil; S5. Improve the soil to enhance its strength and stability; S6. Real-time monitoring of foundation pit, including displacement, groundwater level and soil pressure; S7. Carry out construction in stages, ensuring quality inspection and safety assessment at each stage; S8. After acceptance, implement layered backfilling to ensure the compactness of the fill.

2. The method for building foundation construction under complex geological conditions according to claim 1, characterized in that: The S1 step includes the following specific steps: S1.

1. Select appropriate equipment for soil sampling and testing, including rotary drilling machines, standard penetration testers and electromagnetic detectors; S1.

2. Set up multiple drilling points in the construction area and drill the soil layers at predetermined intervals with a drilling depth of 25m-35m to obtain the physical and mechanical properties of each soil layer; S1.

3. Conduct laboratory tests on the collected soil samples to determine the density, moisture content, friction angle and cohesion of the soil layer; S1.

4. Use electromagnetic detection and seismic reflection methods for non-destructive testing to identify groundwater levels, soil layer distribution and potential geological risks, and record groundwater level changes and their impact on soil stability; S1.

5. Comprehensively analyze the data obtained above to evaluate the soil characteristics, groundwater level changes and potential geological risks in the construction area.

3. The method for building foundation construction under complex geological conditions according to claim 1, characterized in that: In step S2, the slope angle of the foundation pit is 30°-45° to ensure the stability of the slope.

4. The method for building foundation construction under complex geological conditions according to claim 1, characterized in that: In the step S3, the spacing between the dewatering wells is 8m-15m, and the pumping flow rate is set to keep the water level lowered.

5. The method for building foundation construction under complex geological conditions according to claim 1, characterized in that: The S4 step includes the following specific steps: S4.

1. Select appropriate deep mixing equipment and calibrate the position of each mixing pile to ensure the verticality and position of the pile are accurate; S4.

2. The diameter of the deep mixing pile should be controlled to be 600mm-700mm, and the mixing depth should be 4.5m-6m; S4.

3. During the construction of the mixing pile, cement slurry is mixed with the soil in a ratio of 1:8 to ensure full mixing to form the pile body; S4.

4. During the mixing process, monitor the fluidity of the cement slurry to ensure that the slurry fully penetrates into the soil, and record the injection pressure of the slurry. The pressure should be controlled at 0.8-1.2MPa.

6. The method for building foundation construction under complex geological conditions according to claim 1, characterized in that: The soil improvement methods in step S5 are grouting and biological soil consolidation.

7. The method for building foundation construction under complex geological conditions according to claim 1, characterized in that: The grouting soil consolidation is carried out by injecting cement slurry, and the ratio of cement to water in the slurry is 1:1.

5.

8. The method for building foundation construction under complex geological conditions according to claim 1, characterized in that: The biological soil-fixing material is a microbial agent or a plant root promoter, and the addition ratio is 1%-5% of the soil mass.

9. The method for building foundation construction under complex geological conditions according to claim 1, characterized in that: In the step S6, real-time monitoring is performed by using a level meter, a displacement sensor and a mixed multi-stage water level gauge, which is set at the slope and bottom of the foundation pit to obtain displacement data and water level changes in real time.

10. The method for building foundation construction under complex geological conditions according to claim 1, characterized in that: The backfill materials in step S8 include sand, gravel, soil and mixed materials. When backfilling in layers, the thickness of each backfill layer is controlled within 30cm-40cm, and mechanical compaction is used to ensure the compactness and stability of the backfill.

Images