Construction method for eliminating self-weight collapsibility of foundation soil of mixed height building

Abstract

The present application relates to the technical field of foundation engineering, in particular to a construction method for eliminating the self-weight collapsibility of mixed-height building foundation soil; first, read the data and establish the foundation treatment unit; then, according to the outer edge of the high-rise building foundation, the outer edge of the low-rise building foundation, the foundation burial depth, the load distribution and the interface of the collapsible soil layer, the foundation treatment unit is divided into a high-rise building area, a low-rise building area and a boundary transition coordination area; then, according to the foundation bottom elevation of each area, the bottom interface of the collapsible soil layer, the load action range and the remaining collapsibility control requirements, the treatment depth and the reinforcement strength grade of each foundation treatment unit are determined; then, according to the connection relationship of the high-rise building area, the boundary transition coordination area and the low-rise building area, the partitioned reinforcement body, the anti-seepage structure and the drainage structure are constructed in sequence; finally, the treatment depth, the reinforcement body continuity, the anti-seepage and drainage continuity and the coordinated deformation of each foundation treatment unit are verified, and the foundation treatment units that do not pass the verification are reinforced.

Description

Technical Field

[0001] This invention relates to the field of foundation engineering technology, specifically a construction method for eliminating the self-weight collapsibility of foundation soil in mixed-height buildings. Background Technology

[0002] While collapsible loess sites can temporarily maintain a certain structural strength under natural water content, the soil's pore structure is easily damaged and additional collapsing deformation occurs when rainwater infiltration, pipe network leakage, construction water retention, or changes in groundwater conditions are encountered under the combined effects of building loads and soil self-weight. Existing engineering projects typically employ methods such as dynamic compaction, lime-soil compaction piles, column hammer impact piles, grouting reinforcement, pile foundations penetrating the collapsible layer, seepage prevention curtains, and drainage ditches to treat collapsible loess foundations.

[0003] For a single building, the above methods can improve the foundation bearing capacity and reduce subsidence deformation to some extent. However, in sites where high-rise and low-rise buildings are arranged together, the high-rise building area has a large load, high foundation stiffness, and usually a deeper foundation treatment depth; the low-rise building area has a smaller load and a relatively shallower treatment depth; at the junction of the two, there are often situations such as basement expansion, backfill disturbance, concentrated pipelines, and rainwater collection. If the same pile spacing and treatment depth are still applied, or if reinforcement is carried out separately for the high-rise building, abrupt changes in reinforcement stiffness and inconsistencies in the remaining subsidence can easily occur in the junction area.

[0004] During subsequent immersion or long-term service, the high-rise building area may have stabilized, while the low-rise building area and the transition zone will continue to experience subsidence, leading to differential settlement, cracks, misalignment, and new water ingress channels at the boundary. Current technology lacks a collaborative reinforcement method for high-rise and low-rise building combinations on self-weight collapsible loess foundations, making it difficult to simultaneously control the reinforcement depth, reinforcement stiffness, seepage prevention and drainage paths, and residual subsidence deformation in the high-rise, low-rise, and transition zones before construction. Summary of the Invention

[0005] To address the shortcomings of existing technologies, this invention provides a construction method for eliminating the self-weight collapsibility of foundation soil in mixed-height buildings. This method has advantages such as establishing foundation treatment units in zones, progressively determining treatment depth and reinforcement strength, and simultaneously arranging anti-seepage and drainage structures and verifying and reinforcing them. It solves the problem that existing reinforcement methods are unable to coordinate the differences in load, stiffness, and residual collapsibility deformation between high-rise building areas, low-rise building areas, and transitional areas, which leads to differential settlement and secondary collapsibility deformation in the transitional areas.

[0006] To achieve the above objectives, the present invention provides the following technical solution: a construction method for eliminating the collapsibility of foundation soil under the self-weight of mixed-height buildings, comprising: S1. Read site survey data, building foundation data, load zoning data, collapsibility evaluation data, pipeline data and drainage data, and establish foundation treatment units; S2. Based on the outer edge of the foundation of high-rise buildings, the outer edge of the foundation of low-rise buildings, the foundation depth, the load distribution, and the interface of collapsible soil layer, the foundation treatment unit is divided into high-rise building area, low-rise building area and boundary transition and coordination area. S3. Based on the foundation bottom elevation, collapsible soil layer bottom boundary, load range and remaining collapsible control requirements of each area, determine the treatment depth and reinforcement strength level of each foundation treatment unit; S4. According to the connection relationship between high-rise building area, boundary transition and coordination area and low-rise building area, construct the reinforcement, seepage prevention structure and drainage structure in sequence for each zone. S5. Verify the treatment depth, solidification continuity, seepage prevention and drainage continuity, and coordinated deformation of each foundation treatment unit, and reinforce the foundation treatment units that fail the verification.

[0007] Furthermore, in S1, the foundation treatment units are formed according to the same plane coordinate reference. Each foundation treatment unit registers the unit number, unit boundary, corresponding building location, foundation bottom elevation, collapsible soil bottom boundary, backfill disturbance status, pipeline crossing status, surface drainage direction, and data source version. The unit number is formed by connecting the project area number, the pre-number of the partition, and the sequence number.

[0008] Furthermore, in S1, foundation treatment units where the bottom boundary of the collapsible soil layer cannot be directly determined are registered as units to be verified. After the units to be verified complete supplementary exploration, collapsible soil layer interface confirmation, and data version update, they proceed to the zoning processing in step S2.

[0009] Furthermore, in S2, the high-rise building area is formed by the projection range of the high-rise building foundation plane and the influence range of its outer edge, the low-rise building area is formed by the projection range of the low-rise building foundation plane and the influence range of its outer edge, and the boundary transition and coordination area is formed by the continuous foundation treatment units between the high-rise building area and the low-rise building area.

[0010] Furthermore, the boundary of the transitional coordination zone is determined based on the outer edge of the foundation of high-rise buildings, the outer edge of the foundation of low-rise buildings, the backfill strip of the basement exterior wall, the pipeline trench, the location of changes in foundation depth, the location of changes in the bottom boundary of collapsible soil layer, and the location of drainage collection. When pipeline trenches cross the boundary between high and low buildings, the foundation treatment units within one to three meters on both sides of the trench enter the boundary transition and coordination zone.

[0011] Furthermore, in S3, the high-rise building area is determined to be a deep high-strength reinforcement level, the low-rise building area is determined to be a shallow to mid-level coordinated reinforcement level, and the boundary transition coordination area is determined to be a progressive coordination reinforcement level. When the difference in treatment depth between adjacent foundation treatment units is greater than two meters, a compensation treatment unit shall be set between them.

[0012] Furthermore, the graded reinforcement is formed by high-side transition zone, middle coordination zone and low-side transition zone. The high-side transition zone is connected to the edge treatment depth of the high-rise building area. The middle coordination zone adopts a treatment depth between the high-side transition zone and the low-side transition zone. The low-side transition zone is connected to the edge treatment depth of the low-rise building area.

[0013] Furthermore, in S4, the construction sequence is as follows: first, construct temporary intercepting ditches, collection wells, drainage channels, and temporary pipeline protection; then, construct the reinforcement of the high-rise building area; subsequently, construct the reinforcement of the boundary transition and coordination zone according to the high-side transition zone, the middle coordination zone, and the low-side transition zone; and finally, construct the reinforcement of the low-rise building area.

[0014] Furthermore, in S5, foundation treatment units that fail verification are reinforced according to the reasons for failure; if the treatment depth is insufficient, the treatment is deepened; if the continuity of the reinforced body fails, a compensation treatment unit is set up; if the continuity of seepage prevention and drainage fails, the seepage prevention structure and drainage structure are repaired; if the collaborative deformation verification fails, the corresponding area of ​​settlement jump is locally reinforced, and a reinforcement version record is generated.

[0015] This invention provides a construction method for eliminating the collapsibility of foundation soil under its own weight in mixed-height building structures. Compared with existing technologies, it has the following advantages: 1. This method first establishes foundation treatment units, then divides the self-weight collapsible loess foundation into high-rise building areas, low-rise building areas, and transitional zones, and determines the treatment depth and reinforcement strength level for each. This ensures a continuous connection between deep reinforcement in high-rise building areas, shallow to mid-level coordinated reinforcement in low-rise building areas, and progressive coordinated reinforcement in transitional zones. This allows for zoned control of abrupt changes in treatment depth, reinforcement stiffness, and collapsibility deformation before foundation construction, addressing the differential settlement problem in the transitional zone caused by differences in load diffusion depth, foundation stiffness, and residual collapsibility between high-rise and low-rise buildings. This reduces cracks, misalignments, and secondary water ingress channels at the transitional zone caused by continued collapsibility in low-rise building areas and transitional zones, even when the high-rise building area has stabilized.

[0016] 2. This method also involves simultaneously setting up seepage prevention and drainage structures during the construction of the zoned reinforcement, and verifying the treatment depth, reinforcement continuity, seepage prevention and drainage continuity, and coordinated deformation after construction. This ensures that each foundation treatment unit has clear construction records, verification basis, and reinforcement path. For foundation treatment units with insufficient treatment depth, interrupted reinforcement, discontinuous seepage prevention and drainage, or sudden settlement in the boundary area, reinforcement can be carried out according to the corresponding cause before the foundation closure construction. This reduces the probability of relying on jacking correction, secondary grouting, and local rework in the later stage, and improves the traceability and construction stability of the reinforcement results of collapsible loess foundations under the combined action of high and low buildings. Attached Figure Description

[0017] Figure 1 This is an overall flowchart of the method of the present invention; Figure 2 This is a flowchart for confirming the reinforcement strength level of the present invention. Detailed Implementation

[0018] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0019] First Embodiment Please see Figure 1 as well as Figure 2 This application provides a construction method for eliminating the collapsibility of foundation soil under the self-weight of mixed-height buildings, comprising the following steps: S1. Read site survey data, building foundation data, load zoning data, collapsibility evaluation data, pipeline data, and drainage data to establish foundation treatment units. Specific implementation details are as follows: Before construction, the following documents should be read in a unified manner: geotechnical engineering investigation report, collapsible loess evaluation record, well and borehole exposure record, building foundation plan, foundation bottom elevation record, structural load zoning data, basement boundary data, pipeline layout data, site drainage data, and existing backfill disturbance data.

[0020] The reading order is as follows: First, determine the top boundary and bottom boundary of the collapsible soil layer, the self-weight collapsibility determination results, and the corresponding positions of each borehole from the survey data. Then, determine the outer edge of the foundation of high-rise buildings, the outer edge of the foundation of low-rise buildings, the foundation depth, and the foundation type from the building foundation data. Finally, determine the rainwater pipes, water supply and drainage pipes, inspection wells, backfill strips of the basement exterior walls, site slope, and temporary drainage outlets from the pipeline data and drainage data.

[0021] The above data were then overlaid and registered according to the same plane coordinate datum, without directly replacing the on-site coordinates with relative distances from different drawings. The plane coordinate datum was established using fixed control points in the construction survey control network, and the building axis, foundation outer edge, pipeline centerline, manhole center point, drainage ditch edge, and basement outer wall edge were all converted to the same coordinate datum for registration.

[0022] For locations in drawings that are only expressed by axial distance, component number, and distance to adjacent structures, their actual locations should be verified by on-site layout before being recorded in the foundation treatment unit data table; locations that have not been verified on-site will not be used as the direct basis for subsequent zoning boundaries.

[0023] The foundation treatment unit is formed according to the grid that can be laid on the ground during construction. The grid boundary is connected with the building axis, the outer edge of the foundation, the pile layout line, the edge of the pipeline trench and the edge of the drainage structure. When the boundaries of adjacent data do not coincide, the outer edge of the foundation and the actual measured position of the pipeline after on-site verification shall be used as the standard for re-registration.

[0024] The dimensions of the foundation treatment unit are determined according to the operating width of the construction equipment, the spacing of the pile positions, the location of changes in the foundation boundary, and the requirements for subsequent testing points. The foundation treatment units within the same treatment area adopt a unified numbering system, and the existing numbering is not changed due to changes in subsequent construction batches.

[0025] Each foundation treatment unit is assigned a fixed number, which is formed by connecting the project area number, the zone pre-number, and the sequence number. The same number cannot be reused within the same construction batch. Each foundation treatment unit is simultaneously registered with its unit boundary, unit area, corresponding building location, foundation bottom elevation, collapsible soil layer bottom boundary, backfill disturbance status, pipeline crossing status, surface drainage direction, and data source version.

[0026] Unit boundary registration uses the coordinates of the four corners, the coordinates of the boundary inflection points, and the numbers of adjacent units to express the boundary; unit area registration uses the boundary formed after on-site verification, and does not directly use the theoretical area in the design drawings; the corresponding building part is registered as a specific part under the foundation of high-rise buildings, under the foundation of low-rise buildings, the outer edge area of ​​the foundation, the backfill strip of the basement exterior wall, the area through which pipeline trenches pass, and the area adjacent to drainage structures.

[0027] When registering backfill disturbance, specify the source of disturbed soil, disturbance depth, backfill time, compaction record, and water content anomaly record; when registering pipeline crossing, specify the pipeline type, pipe diameter, burial depth, interface location, manhole location, and current status of seepage prevention protection; when registering surface drainage direction, specify the apron slope direction, ground slope direction, drainage ditch flow direction, and location of temporary drainage outlet.

[0028] If the borehole spacing makes it impossible to directly determine the bottom boundary of the collapsible soil layer in a certain foundation treatment unit, the source of the collapsible soil layer interface of the unit shall be jointly registered with the adjacent boreholes, exploration wells and field supplementary probing data, and the unit shall be marked as a unit to be verified. The unit to be verified shall not enter the subsequent zoning treatment depth determination before the supplementary exploration and boundary confirmation are completed.

[0029] The formation rules for units awaiting review are as follows: There are no direct borehole exposure records within the unit, and adjacent boreholes show a difference in the bottom boundary of the collapsible soil layer greater than two meters; the unit is located at at least one of the following locations: the outer edge of a high-rise building foundation, the outer edge of a low-rise building foundation, the backfill strip of a basement exterior wall, a pipeline trench crossing area, and a drainage collection point; the unit exhibits at least one of the following on-site conditions: old backfill, old trench, traces of old foundation demolition, and abnormal water content. After supplementary probing, sampling review, on-site boundary re-measurement, and data version update are completed for the unit awaiting review, the pending review status is cancelled, and the process proceeds to step S2 for zoning processing.

[0030] The foundation treatment unit formed in this way is not a simple construction grid, but the smallest treatment object shared by subsequent zoning, reinforcement depth determination, seepage prevention and drainage layout, and verification and reinforcement. All subsequent construction records are written back to the same foundation treatment unit number to avoid inconsistencies between treatment areas, testing areas, and reinforcement areas.

[0031] In cases where the treatment scope needs to be changed due to on-site obstacles, pipeline avoidance, and adjustments to the construction sequence, the original foundation treatment unit is not directly deleted. Instead, an adjustment record is created under the original number, and an adjacent compensation treatment unit is added, so that the original data, construction data, testing data, and reinforcement data can be traced by number.

[0032] S2. Based on the outer edge of the foundation of high-rise buildings, the outer edge of the foundation of low-rise buildings, the foundation depth, the load distribution, and the interface of collapsible soil layer, the foundation treatment unit is divided into a high-rise building area, a low-rise building area, and a transitional and coordinated boundary area. The specific implementation is as follows: After the foundation treatment unit is formed, the zoning boundary is determined based on the outer edge of the foundation of high-rise buildings, the outer edge of the foundation of low-rise buildings, the foundation depth, the load distribution, and the interface of the collapsible soil layer.

[0033] The high-rise building area is formed by the planar projection range of the high-rise building foundation and the influence range of its outer edge. The influence range of the outer edge of the foundation is registered according to the treatment boundary of the outer edge of the high-rise building foundation extending outward in the design documents. If the design documents do not register it separately, the initial boundary is the range of the outer edge of the high-rise building foundation extending outward by no less than one foundation depth and no less than three meters. Then, the boundary is verified on site in combination with the thickness of the collapsible soil layer and the operating range of construction machinery.

[0034] The zoning boundary of high-rise building areas should also cover the corner locations of high-rise foundations, the outer edge of core tube foundations, the edge of pile-raft foundations, locations where raft slab thickness changes, and the locations where basement exterior walls meet. When the above locations are above self-weight collapsible loess layers, adjacent foundation treatment units should not be registered as ordinary low-rise areas. Low-rise building areas are formed by the planar projection range of low-rise building foundations and the influence range of the outer edge of the foundations, and include the treatment units corresponding to the outer drainage of low-rise buildings, the backfill strip outside the low-rise foundations, and the rainwater inlets near low-rise buildings.

[0035] When registering the boundaries of low-rise building areas, it is necessary to distinguish between the unit below the foundation of the main structure of the low-rise building, the outer edge unit of the low-rise building, and the drainage impact unit of the low-rise building. The unit below the foundation of the main structure of the low-rise building is used to determine the foundation bearing capacity and the depth of the collapse treatment. The outer edge unit of the low-rise building is used to connect the outer backfill and the drainage. The drainage impact unit of the low-rise building is used for the subsequent layout of the seepage prevention and drainage structure.

[0036] The transitional zone is formed by the continuous foundation treatment units between the high-rise building area and the low-rise building area. Its boundary is not determined by a single line of structural settlement joint, but by the outer edge of the high-rise building foundation, the outer edge of the low-rise building foundation, the backfill strip of the basement exterior wall, the pipeline trench, the location of foundation depth change, the location of collapsible soil bottom boundary change, and the location of drainage collection.

[0037] The core boundary of the transitional coordination zone is a continuous unit zone between the edge treatment units of high-rise building area and low-rise building area; when structural settlement joints, basement exterior walls, post-cast strips, equipment trenches and rainwater pipelines are all located within this continuous unit zone, they are registered according to the outer boundary of the continuous unit zone, and the above structures are not separately divided into independent zones.

[0038] When the clear distance between the foundations of high-rise buildings and low-rise buildings is less than ten meters, all foundation treatment units between them shall enter the boundary transition and coordination zone; when the clear distance is greater than ten meters, the boundary transition and coordination zone shall at least cover the area three to five meters outside the outer edge of the foundation of the high-rise building, the area three to five meters outside the outer edge of the foundation of the low-rise building, and the continuous area between them where the treatment depth needs to change.

[0039] For situations where the clear distance is greater than ten meters but there are basement exterior wall backfill strips, rainwater wells, pipeline trenches, and old backfill disturbance areas in between, the corresponding foundation treatment units in between continue to enter the boundary transition and coordination zone, and are not treated as ordinary site blank areas. When pipeline trenches cross the boundary between high-rise and low-rise buildings, the foundation treatment units within a range of one to three meters on both sides of the trench are incorporated into the boundary transition and coordination zone along the direction of the trench; when the basement exterior wall backfill strip is adjacent to the foundation of the low-rise building, the unit containing the backfill strip and its outer drainage structure is incorporated into the boundary transition and coordination zone.

[0040] The extent of pipeline trenches in the transitional coordination zone is determined jointly by the trench excavation boundary, pipeline interface location, manhole outer edge, and backfill disturbance range. When trench backfill records are missing, the loose backfill boundary found on-site is used as the trench influence boundary. After zoning, a zoning record is generated, specifying the foundation treatment unit number, zoning name, basis for entering the zoning, adjacent zoning numbers, and boundary effective version.

[0041] The zoning record also registers adjacent units on the high-rise side, adjacent units on the low-rise side, boundary direction, pipeline crossing status, drainage collection status, and adjacent status of basement exterior walls. If a foundation treatment unit simultaneously meets the conditions of both the low-rise building area and the boundary transition coordination zone, it is registered as a boundary transition coordination zone; if a foundation treatment unit simultaneously meets the conditions of both the high-rise building area and the boundary transition coordination zone, it is registered as an edge unit of the high-rise building area and connected to the boundary transition coordination zone in the adjacency relationship.

[0042] For foundation treatment units that simultaneously meet multiple boundary conditions, duplicate numbering is not used; instead, a unique zoning name is determined through a zoning priority rule. The zoning priority rule is as follows: high-rise building zone edge units take precedence over boundary transition and coordination zones, boundary transition and coordination zones take precedence over low-rise building zones, and low-rise building zones take precedence over ordinary site outer edge units.

[0043] After this zoning, the high-rise building area, low-rise building area, and boundary transition and coordination area are continuously connected on the plane, and the subsequent treatment depth and reinforcement intensity can form a progressive relationship from the high-rise side to the low-rise side. After the zoning record takes effect, the zoning name of any foundation treatment unit shall not be changed without on-site verification record; if a change is necessary, the reason for the change, the affected units and adjacent units shall be registered first, then the effective version of the boundary shall be updated, and at the same time it shall be checked whether the treatment depth and reinforcement intensity registration form needs to be regenerated.

[0044] S3. Based on the foundation bottom elevation, collapsible soil layer bottom boundary, load application range, and remaining collapsibility control requirements of each area, determine the treatment depth and reinforcement strength grade of each foundation treatment unit. The specific implementation is as follows: After the zoning records take effect, the treatment depth and reinforcement strength level are determined for each foundation treatment unit. The treatment depth is first determined based on the corresponding foundation bottom elevation, and then determined in conjunction with the bottom boundary of the collapsible soil layer, the range of building load, and the remaining collapsibility control requirements.

[0045] The treatment depth in high-rise building areas covers the soil layers most affected by collapsible deformation below the foundation of high-rise buildings. When high-rise buildings use pile foundations or pile-raft foundations, the pile tip enters the stable bearing layer confirmed by the design. Soil layers that are not penetrated by the pile tip and may still generate collapsible negative friction on the pile side are treated by compaction, mixing, grouting and composite treatment to eliminate their adverse effects.

[0046] The treatment depth of the edge unit of the high-rise building area is not determined solely by the central area of ​​the high-rise building, but is jointly determined by the stress diffusion at the edge of the high-rise building foundation, the stiffness change at the edge of the raft slab, and the treatment depth of the adjacent boundary transition and coordination zone, so that the edge unit of the high-rise building area can form a deep connection with the high-side transition zone of the boundary transition and coordination zone.

[0047] The treatment depth in low-rise building areas is determined based on the thickness of the collapsible soil layer below the foundation of the low-rise building and the allowable deformation conditions of the low-rise building. The foundation treatment unit of the low-rise building area near the boundary transition coordination zone shall not directly adopt the shallow treatment depth far away from the boundary, but shall increase the treatment depth according to the low-side transition requirements.

[0048] When there are rainwater inlets, outer edges of drainage outlets, water supply and drainage pipe interfaces, and old trench backfill locations in low-rise building areas, the treatment depth of the corresponding foundation treatment unit shall be determined according to the disturbance reinforcement requirements, and the small load of low-rise buildings shall not be the sole basis for reducing the treatment depth.

[0049] The transitional and collaborative zone adopts a progressively varying processing depth. The processing depth of the high-rise side processing unit is connected with the edge processing depth of the high-rise building area, the middle processing unit adopts an intermediate processing depth, and the processing depth of the low-rise side processing unit is connected with the edge processing depth of the low-rise building area.

[0050] The treatment depth is progressively graded from the high-rise side to the low-rise side, with each grade corresponding to a clearly defined foundation treatment unit number. Construction is not based on terms like "appropriate deepening" or "local reinforcement." When the difference in treatment depth between adjacent foundation treatment units exceeds two meters, a compensation treatment unit is installed between them. The treatment depth of the compensation treatment unit is taken as the intermediate grade between the two treatment depths, and it forms continuous contact with the reinforced bodies on both sides.

[0051] The planar boundary of the compensation treatment unit extends outwards from the contact edge of two adjacent treatment units, with the extension width determined by the minimum operating width of the construction equipment and the overlap width of the reinforced body. After the compensation treatment unit is formed, the connection method between adjacent units should be re-registered; temporary addition of holes in the construction record is not permitted. The reinforcement strength level is determined synchronously with the treatment depth. High-rise building areas are registered as deep, high-strength reinforcement levels, low-rise building areas are registered as shallow to mid-level coordinated reinforcement levels, and transitional coordinated areas are registered as progressively coordinated reinforcement levels.

[0052] The deep high-strength reinforcement level corresponds to a combination of deep compaction piles, deep mixing piles, inter-pile soil compaction, grouting reinforcement, and cushion layer; the shallow to medium-layer coordinated reinforcement level corresponds to a combination of replacement cushion layer, shallow dynamic compaction, shallow to medium-layer compaction piles, local grouting, and surface impermeable layer; the progressive coordinated reinforcement level corresponds to the continuous treatment of the high-side transition zone, the middle coordinated zone, and the low-side transition zone. The reinforcement strength level of the high-side transition zone is close to that of the edge unit of the high-rise building area, the reinforcement strength level of the middle coordinated zone is between that of the high-side transition zone and the low-side transition zone, and the reinforcement strength level of the low-side transition zone is connected to that of the edge unit of the low-rise building area.

[0053] After the treatment depth and reinforcement strength are determined, they are entered into the treatment depth and reinforcement strength registration form. The registration form specifies the foundation treatment unit number, zone name, foundation bottom elevation, bottom boundary of collapsible soil layer, target treatment depth, reinforcement strength grade, connection method between adjacent units, and effective version.

[0054] The registration form also specifies the high-side connection unit, low-side connection unit, compensation treatment unit number, seepage prevention and drainage connection requirements, and construction batch pre-number. If the on-site verification finds inconsistencies between the bottom boundary of the collapsible soil layer, the backfill disturbance range, and the pipeline location and the original data, the corresponding foundation treatment unit data version should be updated first, and then the treatment depth and reinforcement strength of the unit and adjacent units should be re-determined to avoid new abrupt changes in depth and stiffness caused by local adjustments.

[0055] When redetermining the treatment depth and reinforcement strength, the original registration form will not be deleted but will be retained as a historical version; the new registration form will only be effective for units that have not yet been constructed, units that need to be repaired, and units that require compensation treatment. Units that have already been verified and entered the effective treatment state will not be directly overwritten due to textual modifications.

[0056] S4. Based on the connection relationship between high-rise building areas, transitional zones, and low-rise building areas, construct the reinforcement, waterproofing, and drainage structures in sequence, as follows: Construction is organized according to the connection relationship between high-rise building areas, boundary transition and coordination areas, and low-rise building areas. Before construction, temporary intercepting ditches, collection wells, drainage channels, and temporary pipeline protection are completed. After confirming that construction water, rainwater, and existing pipeline leakage water will not enter the work surface to be reinforced, the construction of the zoned reinforcement, seepage prevention structure, and drainage structure is carried out.

[0057] Temporary intercepting ditches are laid on the outer edge of the area to be reinforced and on the outer side of the junction of high and low buildings. The bottom of the ditch slopes toward the collection well, and the collection well is connected to the existing drainage outlet of the site through a drainage channel. Temporary pipeline protection involves sealing and inspecting the interfaces of water supply and drainage pipes, rainwater pipes and inspection wells. If leakage is found, it is sealed before reinforcement construction can proceed.

[0058] After the temporary drainage facilities are completed, a drainage pretreatment record is generated, specifying the location of the intercepting ditch, the number of the collection well, the direction of drainage, the location of pipeline protection, and the inspection time. High-rise building areas are constructed according to the deep, high-strength reinforcement level. The locations of pile holes, mixing piles, grouting holes, and cushion layers are all mapped to specific foundation treatment units according to the treatment depth and reinforcement strength registration table. Hole drilling, filling, compaction, mixing, and grouting are recorded according to construction batches; adjacent batches must not be mixed up as the same treatment unit. During deep compaction pile construction, the internal units of the high-rise building area are constructed first, followed by the edge units. After the edge units are completed, a planar position and depth verification is performed between them and the high-side transition zone of the boundary transition and coordination area.

[0059] During grouting and reinforcement construction, grouting should be carried out in sections from deep to shallow. For each section, the grouting depth, grout type, grouting volume, termination conditions, and grout return location should be recorded. If abnormal grout return occurs, the construction of the corresponding treatment unit should be suspended and the abnormal location should be recorded. The boundary transition and coordination zone should be constructed in the order of high-side transition zone, middle coordination zone, and low-side transition zone.

[0060] The high-side transition zone first forms a deep overlap with the edge reinforcement of the high-rise building area. The middle coordination zone then forms a continuous reinforcement boundary with the high-side transition zone. Finally, the low-side transition zone connects with the edge treatment body of the low-rise building area. During the construction of the high-side transition zone, the treatment depth and reinforcement strength shall be implemented in accordance with the connection requirements of the edge unit of the high-rise building area. During the construction of the middle coordination zone, the focus is on controlling the overlap width between adjacent reinforcement bodies and the continuity of the seepage prevention structure. During the construction of the low-side transition zone, the focus is on controlling the planar overlap with the edge treatment body of the low-rise building area and the connection of the shallow seepage prevention layer.

[0061] During construction, no unreinforced gaps should appear in adjacent transition zones. If local gaps are caused by underground obstacles, old foundations, or pipeline avoidance, supplementary grouting holes, short piles, and replacement reinforcement sections should be installed on both sides of the gap, and this location should be registered as a compensation treatment unit. After the compensation treatment unit is completed, its continuity with the high-side transition zone, the central coordination zone, the low-side transition zone, and the edge treatment body of the low-rise building area should be re-examined.

[0062] Construction of low-rise building areas should commence after the completion of the low-side transition zone. Treatment units in low-rise building areas far from the boundary should be constructed according to the shallow to mid-level coordinated reinforcement level, while treatment units near the boundary should be connected to the boundary transition coordination zone according to the low-side transition requirements. When there are old backfill trenches, loose soil around rainwater wells, and basement exterior wall backfill strips in low-rise building areas, the loose soil and abnormally water-bearing soil should be excavated first, followed by replacement, compaction, shallow and mid-level densification, and local grouting, without directly sealing the surface.

[0063] The seepage prevention and drainage structures are constructed simultaneously with the reinforcement construction. Vertical seepage prevention sections are set along the boundary between high and low buildings in the transition and coordination zone. Horizontal seepage prevention layers are set at the outer edge of the foundation and the backfill strip of the basement exterior wall. Seepage prevention sleeve sections are set at the locations where pipeline trenches cross. Reverse filter drainage layers are set on the outer side of the basement exterior wall and the outer side of the low-rise building. The reverse filter drainage layers are connected to the sump and the site drainage ditch.

[0064] Both the seepage prevention structure and the drainage structure are registered with the corresponding foundation treatment unit number. The vertical seepage prevention section and the horizontal seepage prevention layer form a closed connection, and the reverse filter drainage layer and the drainage outlet form a continuous drainage route. During the construction of the seepage prevention sleeve section of the pipeline trench, a compacted cushion layer is first set at the bottom of the trench, seepage prevention side protection layers are set on both sides of the trench, and an inspection backfill layer is set on the upper part of the trench. Observation points are reserved near the inspection wells.

[0065] If the seepage prevention structure of a certain foundation treatment unit is not closed or the drainage direction is unclear, the unit shall not be finally backfilled and sealed. Through this construction sequence, the deep treatment on the high-rise side, the gradual treatment of the boundary area, the coordinated treatment on the low-rise side, and the seepage prevention and drainage control are connected in the same process, without forming independent construction sections that are disconnected from each other.

[0066] After construction is completed, a batch record is generated for each construction batch. The batch record specifies the construction date, construction location, foundation treatment unit number, reinforcement type, seepage prevention structure number, drainage structure number, abnormal handling status, and whether the next construction batch is allowed.

[0067] S5. Verify the treatment depth, reinforcement continuity, seepage prevention and drainage continuity, and coordinated deformation of each foundation treatment unit, and reinforce the foundation treatment units that fail the verification. The specific implementation is as follows: After the solidification, seepage prevention and drainage structures of each zone are completed, the treatment depth, solidification continuity, seepage prevention and drainage continuity and coordinated deformation of each foundation treatment unit are verified.

[0068] The verification of treatment depth is based on construction records, drilling records, mixing depth records, grouting segment records, and on-site sampling data. The actual treatment depth is checked against the treatment depth and reinforcement strength registration form. Foundation treatment units with insufficient depth are registered as units where the treatment depth has not been met. When registering units where the treatment depth has not been met, the target treatment depth, actual treatment depth, difference, corresponding construction batch, and impact on adjacent units must be specified to avoid simply recording "insufficient depth" without determining the reinforcement location.

[0069] The continuity verification of reinforced bodies is carried out continuously along the edges of high-rise building areas, transitional and collaborative zones, and low-rise building areas. It checks whether there are untreated voids, discontinuous sections, loose backfill sections, and abnormally moist sections between adjacent reinforced bodies. If a discontinuous section exists, it is registered as a unit where the continuity of the reinforced body fails.

[0070] The continuity verification of reinforced bodies is judged by plane continuity, depth continuity and material continuity. Planar continuity verification is to check whether the boundaries of adjacent reinforced bodies are in contact. Depth continuity verification is to check whether the bottom elevation of adjacent reinforced bodies meets the connection requirements. Material continuity verification is to check whether there are uncompacted loose interlayers between adjacent treatment sections.

[0071] The continuity verification of seepage prevention and drainage is carried out sequentially along the vertical seepage prevention section, horizontal seepage prevention layer, pipeline trench seepage prevention sleeve section, reverse filter drainage layer and drainage outlet to confirm that there is no back slope, blockage, damage, lack of overlap and no outlet position in the water flow control path; if any of the above situations exist, it is registered as a unit where the continuity of seepage prevention and drainage has not been passed.

[0072] The continuity verification of seepage prevention and drainage also inspected the backfill strip of the basement exterior wall, the area around the inspection well, pipeline interfaces, and the outer edge of the drainage ditch. Any instances of water accumulation, extension of damp zones, or breaches in the seepage prevention layer were recorded in the corresponding foundation treatment unit. For the coordinated deformation verification, settlement observation points, water content observation points, and crack inspection points were set up at the edges of high-rise building areas, the middle of the transitional coordinated zone, the edges of low-rise building areas, the backfill strip of the basement exterior wall, and near pipeline trenches. Records were recorded for four time periods: after construction, before foundation construction, during foundation construction, and after rain.

[0073] Settlement observation points are assigned fixed location numbers, which are linked to the foundation treatment unit numbers; water content observation points record surface dampness, local seepage, water accumulation, and abnormalities around inspection wells; crack inspection points record the location of cracks, their direction of extension, whether they penetrate the seepage prevention layer, and whether they connect to pipeline trenches.

[0074] The verification of coordinated deformation is not based on isolated settlement at a single point, but on the continuous change relationship from the high-rise building area to the boundary transition coordinated area and then to the low-rise building area. When there are sudden settlement jumps, continuous cracks, abnormal water content, water seepage in pipeline trenches, damage to the anti-seepage layer and drainage stagnation in the boundary transition coordinated area, the corresponding foundation treatment unit is registered as a unit that has not passed the coordinated deformation test.

[0075] The registration rule for settlement jumps is: a certain observation point in the boundary transition coordination zone forms a significant abrupt change relative to the two adjacent observation points on both sides, and the location of the abrupt change corresponds to at least one of the following field records: solidification discontinuity, backfill disturbance, water content anomaly, and seepage prevention structure defect.

[0076] Foundation treatment units that fail verification will proceed to reinforcement processes based on the reasons for failure: if the treatment depth is insufficient, additional holes, additional piles, deeper mixing, and segmented grouting will be added; if the reinforcement is interrupted, a compensation treatment unit will be set up in the interrupted section and the reinforcement will be supplemented; if the seepage prevention and drainage are discontinuous, the seepage prevention section will be extended, the horizontal seepage prevention layer will be repaired, the seepage prevention sleeve section of the pipeline trench will be redone, and the drainage route will be cleared; if the coordinated deformation fails, the water source and seepage prevention and drainage path will be checked first, and then local grouting, replacement, and compaction reinforcement will be carried out in the corresponding areas of sudden settlement.

[0077] After reinforcement is completed, a reinforcement version record is generated. The reinforcement version record specifies the original foundation treatment unit number, the reason for failure, the reinforcement location, the reinforcement method, the review time, and the review conclusion. After the review is passed, the foundation treatment unit enters the effective treatment state. If the review fails, the failure state is retained and cannot be used as the basis for foundation closure construction.

[0078] The conditions for a valid treatment status are that the treatment depth verification, the reinforcement continuity verification, the seepage prevention and drainage continuity verification, and the coordinated deformation verification are all passed. If all four verifications are not passed simultaneously, the treatment status will not be registered as valid. The reinforcement version record must not overwrite the original construction record. The original construction record, the failure record, the reinforcement record, and the review record are all kept under the same foundation treatment unit number.

[0079] Before foundation construction, the status of all foundation treatment units is summarized. Foundation treatment units that have not passed the review or are pending verification are not allowed to enter the closed construction area of ​​the foundation. For foundation treatment units that have entered the effective treatment state, if new water content anomalies, crack extensions, and drainage blockages are found during post-rain inspections, the corresponding unit's coordinated deformation verification and seepage prevention and drainage continuity verification are restarted. This enables the verification, reinforcement, and review to form a closed process, and provides clear construction basis and traceability for the reinforcement results of high-rise building areas, low-rise building areas, and boundary transition areas.

[0080] Second Embodiment In a specific engineering embodiment, the construction site is located in a self-weight collapsible loess area, and an 18-story high-rise building and a 3-story low-rise building are arranged on the site. The high-rise building adopts a pile raft foundation, and the low-rise building adopts a strip foundation.

[0081] The foundation bottom elevation of high-rise buildings is -6.80 meters, and the foundation bottom elevation of low-rise buildings is -2.20 meters. Geotechnical engineering investigation data shows that the top boundary of the collapsible soil layer in the site is located 1.20 meters to 1.80 meters below the natural ground level, and the bottom boundary of the collapsible soil layer is located 10.50 meters to 15.80 meters below the natural ground level.

[0082] The net distance between the outer edge of the foundation of the high-rise building and the outer edge of the foundation of the low-rise building is 8.60 meters. There is a basement exterior wall backfill strip and a rainwater pipeline trench between them. The rainwater pipeline is buried at a depth of 2.40 meters and the trench is 1.20 meters wide. There are backfill disturbance records on both sides of the trench.

[0083] Before construction, foundation treatment units are established based on the same plane coordinate benchmark. The plane dimensions of each foundation treatment unit are 3 meters × 3 meters. When encountering the outer edge of the foundation, the edge of the pipeline trench, and the edge of the drainage structure, the boundary of the foundation treatment unit is adjusted according to the edge line after on-site verification.

[0084] The foundation treatment units within the projected area of ​​the foundation plane of high-rise buildings and within 4 meters outside it are registered as high-rise building areas, while the foundation treatment units within the projected area of ​​the foundation plane of low-rise buildings and within 3 meters outside it are registered as low-rise building areas. Since the net distance between the outer edges of the foundations of high-rise buildings and low-rise buildings is less than 10 meters, all foundation treatment units between them are registered as boundary transition and coordination zones; the foundation treatment units within 2 meters on both sides of the rainwater pipeline trench are also registered as pipeline trench influence units within the boundary transition and coordination zones.

[0085] In this embodiment, the target treatment depth for the high-rise building area is 15.50 meters below the natural ground level, and a deep high-strength reinforcement grade is adopted, corresponding to deep compaction piles combined with pile compaction and cushion layer treatment; the target treatment depth for the low-rise building area far from the boundary transition coordination zone is 5.00 meters below the natural ground level, and a shallow to medium-level coordinated reinforcement grade is adopted, corresponding to replacement cushion layer combined with shallow and medium-level compaction pile treatment.

[0086] The transition and coordination zone is divided into a high-side transition zone, a central coordination zone, and a low-side transition zone along the direction from the high-rise building area to the low-rise building area. The high-side transition zone is 3 meters wide, with a target treatment depth of 13.00 meters below the natural ground level; the central coordination zone is 3 meters wide, with a target treatment depth of 9.00 meters below the natural ground level; and the low-side transition zone is 3 meters wide, with a target treatment depth of 6.50 meters below the natural ground level.

[0087] Since the treatment depth difference between the high-side transition zone and the central coordination zone is 4.00 meters, a compensation treatment unit with a width of 1.50 meters is added between them, with a target treatment depth of 11.00 meters below the natural ground level; since the treatment depth difference between the central coordination zone and the low-side transition zone is 2.50 meters, a compensation treatment unit with a width of 1.50 meters is added between them, with a target treatment depth of 7.80 meters below the natural ground level.

[0088] During construction, a temporary intercepting ditch is first set up on the outer side of the boundary between high and low buildings. The bottom width of the intercepting ditch is 0.30 meters and the depth is 0.40 meters, with a slope towards the collection well. The collection wells are spaced 20 meters apart and are connected to the temporary drainage outlet of the site through a drainage channel.

[0089] Before constructing the rainwater pipeline trench, a compacted cushion layer with a thickness of 0.30 meters is set at the bottom of the trench, an anti-seepage side protection layer is set on both sides of the trench, and an inspectable backfill layer is set on the top of the trench.

[0090] A vertical seepage-proof section is installed in the transition zone, with its bottom end extending 0.50 meters below the target treatment depth of the lower-side transition zone. A horizontal seepage-proof layer is installed on top of the basement exterior wall backfill strip, with an overlap width of 0.50 meters between the horizontal seepage-proof layer and the vertical seepage-proof section. A reverse-filtration drainage layer, 0.30 meters thick, is installed outside the basement exterior wall backfill strip and connected to the adjacent sump.

[0091] The reinforcement construction is carried out in the following order: high-rise building area, high-side transition zone, central coordination zone, low-side transition zone, and low-rise building area. In the high-rise building area, the deep compaction piles have a diameter of 0.45 meters and a spacing of 1.20 meters; in the high-side transition zone, the pile diameter is 0.45 meters and the spacing is 1.30 meters; in the central coordination zone, the pile diameter is 0.40 meters and the spacing is 1.50 meters; in the low-side transition zone, the pile diameter is 0.40 meters and the spacing is 1.70 meters; and in the low-rise building area, the shallow and medium-layer compaction piles have a diameter of 0.35 meters and a spacing of 1.80 meters.

[0092] The above-mentioned pile diameter and pile spacing are only applicable to the site conditions corresponding to this embodiment. Other projects should be re-determined based on survey data and design documents. During construction, drilling, filling, compaction, and backfilling should all be recorded according to the foundation treatment unit number; the pipeline trenching impact unit should not be mixed with the adjacent ordinary low-rise building area unit.

[0093] After construction is completed, the treatment depth, reinforcement continuity, seepage prevention and drainage continuity, and coordinated deformation of each foundation treatment unit are verified.

[0094] The processing depth verification showed that the actual processing depth in the high-rise building area was 15.40 meters to 15.70 meters, the actual processing depth in the high-side transition zone was 12.90 meters to 13.10 meters, the actual processing depth in the central coordination zone was 8.90 meters to 9.20 meters, the actual processing depth in the low-side transition zone was 6.40 meters to 6.70 meters, and the actual processing depth in the low-rise building area was 4.90 meters to 5.20 meters.

[0095] For the coordinated deformation verification, settlement observation points were set up at the edge of the high-rise building area, the middle of the transition coordination zone, the edge of the low-rise building area, and both sides of the pipeline trench. Three consecutive observations were conducted before foundation construction, with an interval of 7 days between two adjacent observations.

[0096] If a sudden settlement jump occurs at the observation point in the middle of the transition coordination zone relative to the adjacent observation points on both sides, and the location of the jump corresponds to the pipeline trench affected unit, then first check the pipeline trench seepage prevention sleeve section and reverse filter drainage layer, and then perform local grouting reinforcement on the pipeline trench affected unit.

[0097] After the local grouting reinforcement is completed, a reinforcement version record is generated. The reinforcement version record specifies the original foundation treatment unit number, reinforcement hole location, reinforcement depth, grouting section location, review time, and review conclusion. After the review is passed, the corresponding foundation treatment unit is registered as a valid treatment status.

[0098] The number of high-rise building floors, number of low-rise building floors, foundation bottom elevation, collapsible soil layer interface, partition width, treatment depth, pile diameter, pile spacing, anti-seepage overlap width, and observation interval involved in this embodiment are all implementation parameters under the specific engineering conditions, used to illustrate the implementation process of this method, and are not limited to values ​​in other projects.

[0099] Other projects can determine the corresponding parameters based on geotechnical engineering investigation data, building foundation data, load zoning data, collapsibility evaluation data, pipeline data, and drainage data, without changing the foundation treatment unit establishment, three-zone division, determination of progressive treatment depth, zoning construction, and verification and reinforcement process.

[0100] Some of the data in the above formulas are numerical calculations with dimensions removed, and the contents not described in detail in this specification are all prior art known to those skilled in the art.

[0101] The above embodiments are only used to illustrate the technical methods of the present invention and are not intended to limit it. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical methods of the present invention without departing from the spirit and scope of the technical methods of the present invention.

Claims

1. A construction method for eliminating the collapsibility of foundation soil under its own weight in mixed-height buildings, characterized in that, Includes the following steps: S1. Read site survey data, building foundation data, load zoning data, collapsibility evaluation data, pipeline data and drainage data, and establish foundation treatment units; S2. Based on the outer edge of the foundation of high-rise buildings, the outer edge of the foundation of low-rise buildings, the foundation depth, the load distribution, and the interface of collapsible soil layer, the foundation treatment unit is divided into high-rise building area, low-rise building area and boundary transition and coordination area. S3. Based on the foundation bottom elevation, collapsible soil layer bottom boundary, load range and remaining collapsible control requirements of each area, determine the treatment depth and reinforcement strength level of each foundation treatment unit; S4. According to the connection relationship between high-rise building area, boundary transition and coordination area and low-rise building area, construct the reinforcement, seepage prevention structure and drainage structure in sequence for each zone. S5. Verify the treatment depth, solidification continuity, seepage prevention and drainage continuity, and coordinated deformation of each foundation treatment unit, and reinforce the foundation treatment units that fail the verification.

2. The construction method for eliminating the collapsibility of foundation soil under the self-weight of mixed-height buildings according to claim 1, characterized in that, In step S1, the foundation treatment units are formed according to the same plane coordinate reference. Each foundation treatment unit is registered with the unit number, unit boundary, corresponding building location, foundation bottom elevation, collapsible soil layer bottom boundary, backfill disturbance, pipeline crossing, surface drainage direction and data source version. The unit number is formed by connecting the project area number, the pre-number of the partition, and the sequence number.

3. The construction method for eliminating the collapsibility of foundation soil under the self-weight of mixed-height buildings according to claim 1, characterized in that, In step S1, foundation treatment units whose bottom boundary of collapsible soil layer cannot be directly determined are registered as units to be reviewed. After the units to be reviewed complete supplementary exploration, collapsible soil layer interface confirmation and data version update, they enter the zoning processing in step S2.

4. The construction method for eliminating the collapsibility of foundation soil under the self-weight of mixed-height buildings according to claim 1, characterized in that, In step S2, the high-rise building area is formed by the projection range of the high-rise building foundation plane and the influence range of its outer edge, the low-rise building area is formed by the projection range of the low-rise building foundation plane and the influence range of its outer edge, and the boundary transition and coordination area is formed by the continuous foundation treatment unit between the high-rise building area and the low-rise building area.

5. The construction method for eliminating the collapsibility of foundation soil under the self-weight of mixed-height buildings according to claim 1, characterized in that, The boundary of the transitional coordination zone is determined based on the outer edge of the foundation of high-rise buildings, the outer edge of the foundation of low-rise buildings, the backfill strip of the basement exterior wall, the pipeline trench, the location of changes in foundation depth, the location of changes in the bottom boundary of collapsible soil layer, and the location of drainage collection. When pipeline trenches cross the boundary between high and low buildings, the foundation treatment units within one to three meters on both sides of the trench enter the boundary transition and coordination zone.

6. The construction method for eliminating the collapsibility of foundation soil under the self-weight of mixed-height buildings according to claim 1, characterized in that, In step S3, the high-rise building area is determined to be a deep high-strength reinforcement level, the low-rise building area is determined to be a shallow to middle-layer coordinated reinforcement level, and the boundary transition coordinated area is determined to be a progressive coordinated reinforcement level. When the difference in treatment depth between adjacent foundation treatment units is greater than two meters, a compensation treatment unit shall be set between them.

7. A construction method for eliminating the collapsibility of foundation soil under the self-weight of mixed-height buildings according to claim 6, characterized in that, The progressive collaborative reinforcement level is formed by a high-side transition zone, a middle coordination zone, and a low-side transition zone. The high-side transition zone is connected to the edge treatment depth of the high-rise building area, the middle coordination zone adopts a treatment depth between the high-side transition zone and the low-side transition zone, and the low-side transition zone is connected to the edge treatment depth of the low-rise building area.

8. A construction method for eliminating the collapsibility of foundation soil under its own weight in mixed-height buildings according to claim 1, characterized in that, In step S4, the construction sequence is as follows: first, construct temporary intercepting ditches, collection wells, drainage channels, and temporary pipeline protection; then, construct the reinforcement of the high-rise building area; subsequently, construct the reinforcement of the boundary transition and coordination zone according to the high-side transition zone, the middle coordination zone, and the low-side transition zone; and finally, construct the reinforcement of the low-rise building area.

9. A construction method for eliminating the collapsibility of foundation soil under the self-weight of mixed-height buildings according to claim 1, characterized in that, In step S5, foundation treatment units that fail verification are reinforced according to the reasons for failure; if the treatment depth is insufficient, the treatment is deepened; if the continuity of the reinforced body fails, a compensation treatment unit is set up; if the continuity of seepage prevention and drainage fails, the seepage prevention structure and drainage structure are repaired; if the collaborative deformation verification fails, the corresponding area of ​​settlement jump is locally reinforced, and a reinforcement version record is generated.

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