Construction method for adjacent business line bearing platform

Abstract

The invention discloses an adjacent business line bearing platform construction method, which relates to the technical field of bridge construction, and comprises the following three steps: step 1, construction preparation: firstly, carrying out process training on all personnel and completing construction disclosure work at all levels, and secondly, handling construction permission before working; then deeply knowing the building site and the surrounding terrain and the surrounding environment condition, purchasing materials and mechanical equipment for the structure, and finally determining the positions of the pile foundation and the pier of the main pier; 2, investigating and protecting underground pipelines; and thirdly, integral construction of the bearing platform mainly comprises the five steps of combined protection pile construction, main pier pile construction, foundation pit excavation, concrete platform construction and bearing platform construction. By surveying the surrounding environment, adopting brand-new combined protection pile construction and combining all-around monitoring point arrangement, real-time monitoring and protection of an adjacent business line in the construction process are achieved, and the safety and feasibility of the construction process are effectively improved.

Description

Technical Field

[0001] The invention relates to the technical field of bridge construction, and in particular to a method for constructing a cap adjacent to an operating line. Background Art

[0002] In recent years, highways and railways have developed rapidly. With the laying of multiple lines, there will be special situations where highways meet roads or railways. At this time, the project belongs to the construction of adjacent operating lines.

[0003] Before construction, the "Operating Line Construction Safety Agreement" was signed with the railway equipment management unit and the driving organization to clarify safety responsibilities and cooperation projects. The relevant person in charge of each equipment management unit was asked to go to the site to conduct written safety briefings on pipeline equipment, clarify the exact location of underground pipelines and equipment, and determine the relocation and protection measures for pipeline equipment. Strictly abide by the requirements of the adjacent operating line construction and related documents, and organize the construction under the supervision of the equipment management unit to ensure the normal operation of the operating line.

[0004] Among them, the bearing platform refers to a reinforced concrete platform connected to the top of each pile to bear and distribute the load transmitted by the pier body. Columns or piers are built on the bearing platform to form a complete force transmission system. The bearing platform is the connecting part between the pile and the column or pier. The bearing platform connects several or even more than a dozen main pier piles together to form a pile foundation.

[0005] During the construction of new lines, a method for constructing foundations adjacent to operating lines was proposed to enhance construction safety and ensure the absolute safety of driving on adjacent operating lines. Summary of the invention

[0006] The purpose of the present invention is to provide a method for construction of a foundation adjacent to an operating line, which, through reasonable layout, adopts a combination of manually excavated piles and bored piles for protection, and auxiliary monitoring equipment to achieve safety monitoring during the construction process, thereby effectively ensuring the safety of the construction process.

[0007] In order to solve the above technical problems, the present invention adopts the following technical solutions:

[0008] The present invention provides a method for constructing a cap adjacent to an operating line, which is implemented according to the following steps:

[0009] Step 1: Construction preparation. First, all technical and construction workers should be trained in the process and briefed on the construction at all levels. Secondly, before starting the construction, a construction permit should be obtained and an agreement should be signed with relevant units. Then, the construction site and the surrounding terrain and environment should be fully understood, and the materials and mechanical equipment used for the structure should be purchased. Finally, the pile foundation of the main pier and the location of the bridge pier should be determined.

[0010] Step 2: Underground pipeline investigation and protection: Before construction, connect with relevant units to find out the specific conditions of underground pipelines, make detailed records, and focus on protecting pipelines that are close, sensitive to deformation, and large in diameter;

[0011] Step three: The overall construction of the foundation, mainly includes five steps: main pier construction, combined protection pile construction, foundation pit excavation, concrete platform construction and foundation construction.

[0012] Preferably, step one also includes control point review and line setting operations. Before construction, the control points set by the surveying engineer must be reviewed. After the review is correct, the position of the bored piles is set, and then the foundation pit excavation line is set according to the control points.

[0013] At the same time, before excavation of the foundation pit, it is necessary to set up observation points on the existing slope and measure and record the original data.

[0014] Preferably, in step 2, other existing pipelines near the construction site are monitored as a guide, and tracking and protection measures are taken in a timely manner; pipelines that affect the main structure are relocated and protected according to the construction arrangement, and consultation is conducted with the property rights of the underground pipelines to establish management benchmark values ​​for various types of pipelines according to different types of pipelines. The deformation conditions of the pipelines are monitored and measured in a timely manner to ensure that pipeline protection management is effectively carried out in a controllable state; and image data is retained before construction, and a dedicated person is assigned to manage the pipeline protection construction to ensure the safe operation of the operating lines.

[0015] Preferably, in step three, the foundation as a whole includes peripheral bored piles, steel sheet piles, main pier piles, concrete platform and foundation body, the bored piles and steel sheet piles cooperate with each other and are located at the periphery of the construction area, the main pier piles are regularly arranged inside the construction area, the concrete platform is connected to the top of the main pier piles and forms the foundation of the foundation, and the foundation body is cast and formed on the concrete platform.

[0016] Preferably, the main pier piles, concrete platform and foundation body are all provided with reinforcing steel bar components.

[0017] Preferably, the bored piles and steel sheet piles are enclosed in a rectangle or polygon according to construction requirements.

[0018] Preferably, the bored piles are less than 5 meters away from the center line of the adjacent operating line track, and the bored piles are constructed by combining manual excavation piles and bored piles, wherein three groups of bored piles close to the adjacent operating line side are manually excavated piles, and the rest are bored piles.

[0019] Preferably, a plurality of monitoring points are arranged on the steel sheet piles. When the excavation depth of the foundation pit is ≤5m, a total of four monitoring points are arranged, located at the center point of each side of the steel sheet pile cofferdam; when the excavation depth of the foundation pit is ≥5m, a total of eight monitoring points are arranged, located at the center and intersection of each side of the steel sheet pile cofferdam.

[0020] Preferably, the distance between any two adjacent monitoring points is no more than 10 meters, and the number of monitoring points on each side is no less than three.

[0021] Preferably, in step three, the overall construction process of the foundation includes multiple monitoring operations, including the arrangement of monitoring points, monitoring frequency, monitoring of existing lines, foundation pit monitoring and monitoring alarms.

[0022] Compared with the prior art, the beneficial technical effects of the present invention are:

[0023] The present invention provides a method for constructing a foundation adjacent to an operating line, which mainly includes three steps: step one, construction preparation; step two, underground pipeline investigation and protection; and step three, overall construction of the foundation. Step three mainly includes five steps, namely, construction of combined protective piles, construction of main pier piles, excavation of foundation pits, construction of concrete platforms and construction of foundations.

[0024] The present invention, through survey and consideration of the surrounding environment, adopts a new combined protective pile construction, combined with a comprehensive monitoring point arrangement, to achieve real-time monitoring and protection of adjacent operating lines during the construction process, effectively improving the safety and feasibility of the construction process. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] The present invention will be further described below in conjunction with the accompanying drawings.

[0026] Figure 1 This is a flow chart of the method for constructing a cap adjacent to an operating line according to the present invention;

[0027] Figure 2 It is a schematic diagram of the plane relationship between the adjacent operating line cap and the adjacent operating line of the present invention;

[0028] Figure 3 It is a schematic diagram of the relationship between the adjacent business line cap and the adjacent business line elevation of the present invention;

[0029] Figure 4 Plane layout for monitoring points of the cap construction near the operating line of the present invention Figure 1 ;

[0030] Figure 5 Plane layout for monitoring points of the cap construction near the operating line of the present invention Figure 2 ;

[0031] Figure 6 It is a schematic diagram of the plane view of the bored pile construction machinery of the present invention;

[0032] Figure 7 It is a schematic elevation view of the position of the bored pile construction machinery of the present invention;

[0033] Figure 8 It is a schematic diagram of the station plan of the steel sheet pile construction machinery of the present invention;

[0034] Fig. 9 It is a schematic diagram of the vertical view of the steel sheet pile construction machinery of the present invention;

[0035] Fig.10 It is a schematic diagram of the plane view of the construction machinery for hoisting the cap formwork of the present invention;

[0036] Fig.11 It is a schematic elevation view of the construction machinery position for hoisting the cap formwork of the present invention;

[0037] Fig.12 It is a schematic diagram of the plane view of the construction machinery for pouring concrete of the cap body of the present invention;

[0038] Fig.13 This is a schematic elevation view of the construction machinery for pouring concrete for the cap body of the present invention;

[0039] Explanation of the accompanying reference numerals: 1. bored pile; 2. steel sheet pile; 3. main pier pile; 4. concrete platform; 5. foundation body; 6. monitoring point. DETAILED DESCRIPTION

[0040] In order to make the technical problems, technical solutions and beneficial effects to be solved by the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0041] like Figure 1-13 As shown, a method for constructing a foundation adjacent to an operating line is implemented according to the following steps:

[0042] Step 1: Construction preparation. First, all technical and construction workers must receive process training and complete construction briefings at all levels. Secondly, before construction begins, a construction permit must be obtained and an agreement must be signed with relevant units. Then, an in-depth understanding of the construction site and surrounding terrain and surrounding environment must be obtained, and materials and mechanical equipment for the structure must be purchased. Finally, the pile foundation of the main pier and the location of the bridge piers must be determined. Specifically, the surrounding environment and terrain include the stratum structure, rock and soil properties, aquifer properties, groundwater level, permeability coefficient, etc. within a certain depth from the surface to the bottom of the supporting structure. The ground drainage conditions around the deep foundation pit must be understood, as well as the possibility of ground rainwater, running water, and water pipes discharging or leaking into the foundation pit, as well as the vibration and static loads generated by buildings adjacent to the foundation pit, ground loads, and the passage of large vehicles.

[0043] Step 2: Investigation and protection of underground pipelines. Before construction, connect with relevant units to find out the specific conditions of underground pipelines, make detailed records, and focus on protecting pipelines that are close, sensitive to deformation, and large in diameter. Specifically, other pipelines are guided by monitoring and follow-up protection measures are taken in a timely manner. For pipelines that affect the main structure, they are relocated and protected according to the construction arrangement. Consult with the property rights unit of the underground pipelines to establish management benchmark values ​​for various types of pipelines according to different types of pipelines. Through monitoring and measurement, the deformation conditions of pipelines are timely grasped to ensure that pipeline protection management is effectively carried out in a controllable state. In addition, retain image data before construction, assign a dedicated person to manage pipeline protection construction, and ensure the safe operation of the operating lines.

[0044] Step 3: Overall construction of the cap, which mainly includes five steps: main pier construction, combined protection pile construction, foundation pit excavation, concrete platform construction and cap construction;

[0045] Specifically, Figure 6-13 As shown, the main pier piles include multiple ones, which are regularly arranged in the deep foundation pit. The construction work is carried out before the excavation of the foundation pit. The first step is to use a drilling machine to drill holes for the pile foundation. The second step is to lift the prefabricated steel cage and put it into the opened pile foundation hole. The last step is to pour concrete to form it. A total of three steps are required to complete the main pier pile construction work; the main pier pile construction goes deep into the ground, and the main purpose is to ensure the stability of the pile foundation; after the main pier pile construction is completed, the combined protection pile construction is carried out. First, the bored pile construction is carried out, and the construction is carried out close to the side of the adjacent operating line. First, holes are drilled and then poured to form at least one row of protection piles. The remaining periphery is protected by steel sheet piles. After the protection construction is completed, the excavation of the foundation pit is completed by excavation equipment; after the excavation of the foundation pit is completed, the formwork is hoisted for support, and the concrete platform construction is completed after the concrete is poured and formed; after the concrete platform is fully maintained, the cap formwork is hoisted and supported, and the formwork support operations of specified shapes and specifications are carried out according to the design requirements. A reinforced steel mesh is set inside the formwork. After the support is completed, the concrete of the cap body is poured; the overall construction of the cap is completed; finally, the cap formwork is removed after maintenance, and subsequent pier construction is carried out.

[0046] Specifically, step one also includes control point review and line-laying operations. Before construction, the control points placed by the surveying engineer must be reviewed. After the review is correct, the position of the bored piles is released, and then the foundation pit excavation line is released according to the control points. At the same time, before the foundation pit is excavated, observation points need to be set up on the existing line slope, and the original data needs to be measured and recorded.

[0047] Specifically, for foundation caps with good geology and shallow burial depth, the excavation of the foundation pit adopts slope reduction measures, and the slope is 1:0.5. If it is found that this slope cannot meet the requirements during the construction process, the slope can be slowed down or soil bags can be piled up to increase the stability of the foundation pit slope. The base size after excavation is ≥ the size of the foundation structure + 0.5 meters; and it is strictly forbidden to touch the pile foundation with force during the excavation process to avoid damage to the pile foundation.

[0048] Specifically, in step 2, other existing pipelines near the construction site are monitored as a guide, and follow-up protection measures are taken in a timely manner; pipelines that affect the main structure are relocated and protected according to the construction arrangement, and consultation is carried out with the property rights of underground pipelines to establish management benchmark values ​​for various types of pipelines according to different types of pipelines. The deformation status of pipelines is timely grasped through monitoring and measurement to ensure that pipeline protection management is effectively carried out in a controllable state; and image data is retained before construction, and a dedicated person is assigned to manage the pipeline protection construction to ensure the safe operation of the operating lines.

[0049] Specifically, in step 3, the cap as a whole includes peripheral bored piles 1, steel sheet piles 2, main pier piles 3, concrete platform 4 and cap body 5. The bored piles 1 and steel sheet piles 2 cooperate with each other and are located at the periphery of the construction area. The main pier piles 3 are regularly arranged at the bottom of the interior of the construction area. The concrete platform 4 is connected to the top of the main pier piles 3 and forms the foundation for the cap construction. The cap body 5 is cast on the concrete platform 4. After the construction of the cap body 5 is completed, a part of it is located 3 to 5 meters below the ground, and the top protrudes 1 to 3 meters above the ground. In one specific embodiment, the total height of the cap body 5 is 5 meters, and the underground and above-ground parts are 3 meters and 2 meters respectively. Specifically, the main pier piles 3, the concrete platform 4 and the cap body 5 are all provided with reinforcing steel bar components to ensure the firmness of the construction foundation at the bottom of the cap, and have sufficient strength to ensure its service life.

[0050] Specifically, the bored piles 1 and the steel sheet piles 2 are enclosed in a rectangle or a polygon according to construction requirements.

[0051] Specifically, the bored pile 1 is less than 5 meters away from the center line of the adjacent operating line track. The bored pile 1 is constructed by combining manual excavation piles and bored piles. Among them, three groups of bored piles close to the adjacent operating line are manually excavated piles, and the rest are bored piles. Bored piles with small vibration amplitude are used to form protection, which effectively reduces the impact of construction work on existing lines.

[0052] In a specific embodiment of the present invention, Figure 6-13As shown in the figure, the pier is located between a certain up line and a certain passenger dedicated down line, and is less than 5 meters away from a certain up line. According to preliminary exploration, the distance between the bored piles of the foundation and the existing track is 3.77 to 29.64 meters. During construction, the order of protection first and then construction is adopted. The protective piles are combined, a small part is bored piles and a large part is steel sheet piles. Specifically, the side close to the adjacent operating line is preferentially protected by bored piles 1, and the length and range of protection are adjusted according to actual needs; the other three sides are protected by steel sheet piles. Specifically, during the construction of bored piles 1, the area less than 6 meters away from the center of the existing operating line track is artificially excavated piles, and the rest are bored piles; among them, steel sheet piles 2 are protected by Larsen IV steel sheet piles, the surrounding purlins are double-jointed I40a or triple-jointed I40a, and the internal support is 630×8mm steel pipe piles. During construction, wind ropes are set on the swing arms of the equipment to improve its stability and safety.

[0053] Specifically, Figure 4-5 As shown, a plurality of monitoring points 6 are arranged on the steel sheet pile 2. When the excavation depth of the foundation pit is ≤5m, a total of four monitoring points 6 are arranged, which are located at the center point of each side of the steel sheet pile cofferdam; when the excavation depth of the foundation pit is ≥5m, a total of eight monitoring points 6 are arranged, which are located at the center and intersection of each side of the steel sheet pile cofferdam.

[0054] Specifically, the distance between any two adjacent monitoring points 6 is no more than 10 meters, and the number of monitoring points on each side is no less than three.

[0055] Specifically, in step three, the overall construction process of the foundation includes a number of monitoring operations, including the layout of monitoring points, monitoring frequency, monitoring of existing lines, foundation pit monitoring and monitoring alarms. The layout of the monitoring points refers to the above content and is selected and set according to the actual excavation depth of the foundation pit.

[0056] The specific regulations for monitoring frequency are as follows:

[0057] During construction, the initial value is measured one week before the construction of the foundation pit retaining structure, until the construction is completed and the backfilling is completed, and the monitoring data tends to be stable; the initial value of the monitoring project is completed 3 days before the excavation of the foundation pit, and the average value of 3 observations is obtained as the initial value of the monitoring project; the determination of the monitoring frequency should be based on the accurate reflection of the dynamic changes of the foundation pit retaining structure and the surrounding environment, and regular monitoring should be adopted, and follow-up monitoring should be carried out when necessary. In addition, if the deformation rate exceeds the warning value during construction, monitoring should be further strengthened and the monitoring time interval should be shortened as shown in Table 2, so as to provide necessary measured data for improving construction parameters and implementing deformation control measures. The specific monitoring frequency schedule is shown in Table 1.

[0058] Table 1 Monitoring frequency schedule

[0059]

[0060] Table 2 Monitoring time interval

[0061]

[0062] Furthermore, the specific methods of existing line monitoring are as follows:

[0063] A monitoring point is arranged every 20m on the longitudinal shoulder of the existing line, and monitoring points are set more densely at locations where the roadbed settlement and deformation are large. It is preferred to arrange a monitoring point at intervals of 10m or 15m; the observation piles should be prefabricated with steel bars with a diameter of not less than 30mm or No. 150 reinforced concrete, with a length of about 150 to 200cm. A semicircular wear-resistant side head is embedded in the top of the reinforced concrete pile, and the burial depth should not be less than 100cm. A separate monitoring point is set outside the contact network column; in addition, during construction preparation work, observation points are set on adjacent existing contact network pillars. The observation points use adhesive observation marks, and the existing contact network pillars are observed during construction to ensure the safety of the existing lines during construction.

[0064] In addition, the specific contents of the foundation pit monitoring project are as follows:

[0065] In this embodiment, the foundation pit monitoring items are shown in the following table:

[0066] Table 3 Foundation pit monitoring items

[0067]

[0068]

[0069] According to the design, the first-level foundation pit is a foundation pit project with an excavation depth greater than 15m, and the surrounding environmental conditions are complex and the environmental protection requirements are high; the second-level foundation pit is a foundation pit project with an excavation depth of 5<H<15m; the third-level foundation pit is a foundation pit project with an excavation depth less than 5m, and the surrounding environmental conditions of the foundation pit are simple and the environmental protection requirements are not high. Specifically, in one embodiment, if the foundation pit depth is less than 5m, the foundation pit monitoring is carried out according to the third-level foundation pit; if the excavation depth is 5<H<15m, it is carried out according to the second-level foundation pit.

[0070] Among them, the implementation of monitoring alarm:

[0071] Monitoring alarm indicators are generally controlled by two quantities: cumulative change and change rate. The alarm indicator of cumulative change should generally not exceed the design limit.

[0072] Horizontal displacement: The rate of change of horizontal displacement of the cofferdam on the side close to the railway is not more than 2mm / d, the cumulative displacement is not more than 25mm and not more than 0.2H% (H is the design depth of the foundation pit), and the rate of change of horizontal displacement of the other three sides not close to the railway is not more than 3mm / d, the cumulative displacement is not more than 30mm and not more than 0.3H% (H is the design depth of the foundation pit);

[0073] Vertical displacement: The vertical displacement change rate of the cofferdam top on the side close to the railway is not more than 2mm / d, the cumulative displacement is not more than 10mm and not more than 0.1H% (H is the design depth of the foundation pit); the vertical displacement change rate of the other three sides not close to the railway is not more than 3mm / d, the cumulative displacement is not more than 20mm and not more than 0.2H% (H is the design depth of the foundation pit).

[0074] When the deformation exceeds the limit, construction must be stopped and emergency measures such as unloading, backfilling the foundation pit, and pulling anchors should be taken immediately. At the same time, the supervision unit should be reported to ensure the stability of the foundation pit support system.

[0075] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device.

[0076] The embodiments described above are only descriptions of the preferred modes of the present invention, and are not intended to limit the scope of the present invention. Without departing from the design spirit of the present invention, various modifications and improvements made to the technical solutions of the present invention by ordinary technicians in this field should all fall within the protection scope determined by the claims of the present invention.

Claims

1. A method for construction of a cap adjacent to an operating line, characterized in that: Follow these steps to implement: Step 1: Construction preparation. First, all technical and construction workers should be trained in the process and briefed on the construction at all levels. Secondly, before starting the construction, a construction permit should be obtained and an agreement should be signed with relevant units. Then, the construction site and the surrounding terrain and environment should be fully understood, and the materials and mechanical equipment used for the structure should be purchased. Finally, the pile foundation of the main pier and the location of the bridge pier should be determined. Step 2: Underground pipeline investigation and protection: Before construction, connect with relevant units to find out the specific conditions of underground pipelines, make detailed records, and focus on protecting pipelines that are close, sensitive to deformation, and large in diameter; Step three: The overall construction of the foundation, mainly includes five steps: main pier construction, combined protection pile construction, foundation pit excavation, concrete platform construction and foundation construction.

2. The method for construction of a cap adjacent to an operating line according to claim 1, characterized in that: Step 1 also includes control point review and line setting. Before construction, the control points placed by the surveying engineer must be reviewed. After the review is correct, the position of the bored piles is released, and then the foundation pit excavation line is released according to the control points. At the same time, before excavation of the foundation pit, it is necessary to set up observation points on the existing slope and measure and record the original data.

3. The method for construction of a cap adjacent to an operating line according to claim 1, characterized in that: In step two, other existing pipelines near the construction site are monitored and protected in a timely manner. Pipelines that affect the main structure are relocated and protected according to the construction schedule. Consult with the property owners of the underground pipelines and establish management benchmark values ​​for various types of pipelines according to different types of pipelines. Through monitoring and measurement, the deformation status of the pipelines is monitored in a timely manner to ensure that pipeline protection management is carried out effectively in a controllable state. Image data is retained before construction, and a dedicated person is assigned to manage the pipeline protection construction to ensure the safe operation of the operating lines.

4. The method for construction of a cap adjacent to an operating line according to claim 1, characterized in that: In step three, the foundation as a whole includes peripheral bored piles (1), steel sheet piles (2), main pier piles (3), concrete platform (4) and foundation body (5); the bored piles (1) and steel sheet piles (2) cooperate with each other and are located at the periphery of the construction area; the main pier piles (3) are regularly arranged inside the construction area; the concrete platform (4) is connected to the top of the main pier piles (3) and forms the foundation of the foundation; the foundation body (5) is cast and formed on the concrete platform (4).

5. The method for construction of a cap adjacent to an operating line according to claim 4, characterized in that: The main pier pile (3), the concrete platform (4) and the foundation body (5) are all provided with reinforcement steel bar components.

6. The method for construction of a cap adjacent to an operating line according to claim 4, characterized in that: The bored piles (1) and the steel sheet piles (2) are arranged in a rectangular or polygonal shape according to construction requirements.

7. The method for construction of a cap adjacent to an operating line according to claim 6, characterized in that: The bored piles (1) are less than 5 meters away from the center line of the adjacent operating line track. The bored piles (1) are constructed by combining manual excavation piles and bored piles, wherein three groups of bored piles close to the adjacent operating line are manually excavated piles, and the rest are bored piles.

8. The method for construction of a cap adjacent to an operating line according to claim 6, characterized in that: A plurality of monitoring points (6) are arranged on the steel sheet piles (2). When the excavation depth of the foundation pit is ≤5 m, a total of four monitoring points (6) are arranged, located at the center point of each side of the steel sheet pile cofferdam; when the excavation depth of the foundation pit is ≥5 m, a total of eight monitoring points (6) are arranged, located at the center and intersection of each side of the steel sheet pile cofferdam.

9. The method for construction of a cap adjacent to an operating line according to claim 8, characterized in that: The distance between any two adjacent monitoring points (6) is no greater than 10 meters, and the number of monitoring points on each side is no less than three.

10. The method for construction of a cap adjacent to an operating line according to claim 8, characterized in that: Step three: The overall construction process of the foundation includes a number of monitoring operations, including the layout of monitoring points, monitoring frequency, monitoring of existing lines, foundation pit monitoring and monitoring alarms.

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