Differential settlement area elevation control network measurement method

Abstract

The invention relates to the technical field of differential settlement area elevation control, in particular to a differential settlement area elevation control network measurement method, which comprises the following steps: re-measuring a known line elevation control network, calculating a control point measurement section height difference, and updating elevation data after secondary re-measurement confirmation is needed when a standard tolerance is exceeded; determining a differential settlement area, and burying two groups of area control points on two sides of the differential settlement area; and continuously measuring and calculating the regional control point elevation as a settlement area control point detection constraint point, periodically detecting the height difference condition of the control point measurement section in the settlement area, and updating the elevation data when the standard tolerance is exceeded. The area elevation control point with stable settlement is selected as the settlement area control point detection constraint point, so that the problem of settlement of the constraint point is avoided, the accuracy of the elevation result is ensured, the measurement distance is shortened, the measurement data processing is simple, the measurement time is saved, and the change of the control point in the settlement area can be detected; elevation updating can be carried out in time when the standard tolerance is exceeded, so that the construction requirements are met.

Description

Technical Field

[0001] The present invention relates to the technical field of elevation control in differentiated settlement areas, and in particular to a method for measuring an elevation control network in differentiated settlement areas. Background Art

[0002] There will be differential settlement in some parts of the construction line section. The main reasons include the following aspects: (1) Uneven foundation: Differences in soil properties of the foundation are one of the main reasons for differential settlement; differences in soil type, moisture and density in different sections will lead to different bearing capacities of the foundation, thus causing settlement differences. (2) Improper construction methods: During the construction process, if the construction method is improper, such as insufficient compaction, improper selection of fillers, etc., the stability of the foundation will be affected, thus causing differential settlement. (3) Differences in filler quality: Differences in the properties and quality of fillers will also affect the stability of the foundation. For example, using different types or qualities of fillers will lead to different compaction effects, which in turn cause settlement differences.

[0003] At present, there is local differential settlement in the construction line section, which will also lead to uneven settlement of the control points of the elevation control network, making it difficult to meet the construction requirements. In the prior art, in order to solve the problem of uneven settlement of the control points of the elevation control network caused by differential settlement, the traditional method is to re-measure the entire line elevation control network. This re-measurement method is very time-consuming and labor-intensive, and it is difficult to meet the construction requirements. Therefore, it is still a technical difficulty to quickly and accurately measure the uneven settlement of the control points in the settlement area to update the elevation data. Summary of the invention

[0004] In order to overcome the shortcomings of the prior art, the purpose of the present invention is to provide a method for measuring the elevation control network of a differentiated settlement area, which has the advantages of saving time and labor and meeting construction requirements.

[0005] In order to achieve the purpose of the above invention, the technical solution adopted by the present invention is as follows:

[0006] The present invention provides a method for measuring a differential settlement area elevation control network, comprising the following steps:

[0007] S1. Re-survey the line elevation control network: Use the national second-class leveling method to re-survey the line elevation control network and calculate the height difference of the control point. If the height difference of the control point exceeds the standard limit, re-survey and confirm it for the second time before updating the elevation data.

[0008] S2, determining the differential settlement area according to the elevation settlement values ​​of the line control network control points remeasured in step S1 and the geological conditions, and burying two groups of regional control points on both sides of the differential settlement area;

[0009] S3, use the elevation of the line control network after re-survey to continuously measure the regional control points, and then use the national second-class leveling method to measure the height difference of each section and calculate the elevation of the control points of the regional control network as the detection constraint points of the settlement area control points;

[0010] S4. During the construction period, regional control points are used to regularly check the control points in the differential settlement area. The measurement method adopts the national second-class leveling method. If the settlement of the control points in the settlement area is found to exceed the standard limit of the measuring section, the elevation data of the control points are updated according to the measurement data.

[0011] Furthermore, in the step S1, the elevation control network is formed by measuring a plurality of elevation control point paths; the re-measurement method is to measure from a starting control point through a plurality of intermediate control points to reach another end control point to complete the forward measurement route, and then measure from the end control point through a plurality of intermediate control points to reach the starting control point to complete the return measurement route, so as to complete the control network measurement.

[0012] Furthermore, in the step S1, the calculation formula of the specification limit deviation is as shown in Formula I;

[0013] 6√R formula I;

[0014] Wherein, R is the length of the detection section, in kilometers (km).

[0015] Wherein, formula I is expressed as 6 times the square root of R.

[0016] Furthermore, in the step S1, the elevation data is updated after the second re-measurement confirmation. Specifically, if the elevation difference of the measuring section exceeds the standard limit in the first measurement, it is necessary to measure the elevation difference of the measuring section again. If the re-measurement result is consistent with the first measurement result, the elevation data is updated based on the first measurement result.

[0017] Furthermore, in the step S2, the locations where the two groups of regional control points are buried are 1.5km-2.5km away from the two sides of the differential settlement area and other areas; and / or

[0018] The regional control point is selected at a stable location far away from the project construction impact area and on a building with stable settlement; and / or, the building with stable settlement includes one of the existing bridge piers, culverts, house foundations or signal tower foundations outside the construction impact range.

[0019] Furthermore, in the step S2, the regional control points are buried by later implanting stainless steel observation piles or using existing control points, and each group of regional control points should be evenly distributed with no less than 3 control points.

[0020] Furthermore, in the step S3, the continuous measurement includes the control points of the regional control network in the line control network to calculate the elevation together;

[0021] The calculation process is divided into two steps. The first step is to check whether the measurement results meet the standard tolerance requirements, and the second step is to calculate the results. If the first step does not meet the standard tolerance requirements, re-measure until the standard tolerance requirements are met before proceeding to the second step.

[0022] Furthermore, the standard tolerance includes the closure error tolerance of the conforming route as shown in Formula II, the non-conformity tolerance of the round-trip measurement section height difference as shown in Formula III, and the loop closure error tolerance as shown in Formula IV;

[0023] 4√L formula II;

[0024] Where, L is the length of the attached route, in kilometers (km);

[0025] Wherein, formula II is expressed as 4 times the square root of L.

[0026] 4√k formula III

[0027] Where, k is the length of the measurement route, in kilometers (km);

[0028] Wherein, formula III is expressed as the square root of 4 times k.

[0029] 4√F formula IV;

[0030] Wherein, formula IV is expressed as 4 times the square root of F.

[0031] Where F is the length of the loop in kilometers (km).

[0032] Further, the calculation steps of the result adjustment are as follows:

[0033] fh=Σh-(H end-H start)

[0034] fh<4√L

[0035] V=-(Li / L*fh)

[0036] h = hi + V

[0037] Hwait=Hstart+hchange

[0038] Among them, fh is the closing error of the matching leveling; Hstart is the elevation value of the starting point of the line; Hend is the elevation value of the end point of the line; V is the correction value of the height difference of the measuring section; Li is the length of the measuring section, in kilometers (km); L is the length of the matching line, in kilometers (km); h is the height difference of the measuring section after correction; hi is the uncorrected height difference of the measuring section; Hto is the elevation value of the point to be determined.

[0039] Among them, 4√L means the square root of 4 times L.

[0040] Furthermore, in the step S3, the constraint points are used as the starting known points and the ending known points for elevation calculation, and then other elevations to be measured are calculated.

[0041] Compared with the prior art, the present invention has the following beneficial effects:

[0042] (1) A differential settlement area elevation control network measurement method of the present invention calculates the elevation difference of the control point measurement section by re-surveying the known line elevation control network. If it exceeds the standard limit, it needs to be re-surveyed and confirmed for the second time before updating the elevation data; the differential settlement area is determined according to the elevation settlement value and geological conditions of the control points of the re-surveyed line control network, and two groups of regional control points are buried on both sides of the differential settlement area, and the two groups of regional control points are buried at a certain distance; the regional control points are connected with the re-surveyed line control network to calculate the elevation of the regional control points, which are used as the detection constraint points of the settlement area control points, and the elevation difference of the control point measurement section in the settlement area is regularly detected. If it exceeds the standard limit, the elevation data is updated. Therefore, the present invention utilizes buildings or structures whose settlement has stabilized to deploy regional control points to replace the constraint points of the line control network, controls the poor stability of the control points in the differentiated settlement area, and detects the stability of the control points in the settlement area and updates the data. In this way, the measurement can be completed in a short measurement time and the accuracy of the measurement results can be guaranteed, thus avoiding the time-consuming and labor-intensive re-measurement of the entire line and the entire network and the situation where the accuracy cannot be guaranteed. On the other hand, the regional control points divide the original long lines into shorter lines, reduce the error accumulation in the measurement process, and improve the measurement accuracy, which not only ensures the accuracy of the control network, but also meets the construction requirements.

[0043] (2) The present invention provides a differentiated settlement area elevation control network measurement method. By selecting elevation control points in areas where settlement has stabilized as settlement area control point detection constraint points, the problem of settlement at constraint points is avoided, and the accuracy of elevation results is ensured. This not only shortens the measurement distance and simplifies the measurement data processing, thereby saving measurement time, but also can detect changes in control points in the settlement area. If the control points exceed the specification limit, the elevation data can be updated in a timely manner, thereby meeting construction requirements. BRIEF DESCRIPTION OF THE DRAWINGS

[0044] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0045] Figure 1 It is a schematic diagram of control network points and measurement lines of a differentiated settlement area elevation control network measurement method of the present invention. DETAILED DESCRIPTION

[0046] 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 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.

[0047] The terms used in the embodiments of the present invention are only for the purpose of describing specific embodiments, and are not intended to limit the present invention. In the present invention, the singular forms "a", "said" and "the" used in the embodiments and the appended claims are also intended to include plural forms, unless the context clearly indicates other meanings.

[0048] The following describes the invention in conjunction with specific embodiments.

[0049] Example 1

[0050] A method for measuring a differential settlement area elevation control network, characterized in that it comprises the following steps:

[0051] S1. Re-survey the line elevation control network: Use the national second-class leveling method to re-survey the line elevation control network and calculate the height difference of the control point. If the height difference of the measured section exceeds the standard limit, re-survey and confirm it for the second time before updating the elevation data. Figure 1 As shown in the figure, the elevation control network is formed by measuring the paths of several elevation control points; the re-measurement method is to measure from a starting control point through several intermediate control points to another end control point to complete the forward measurement and fit route, and then measure from the end control point through several intermediate control points to the starting control point to complete the return measurement and fit route to complete the control network measurement. Among them, a section measurement refers to measuring from one control point to another control point.

[0052] Among them, the calculation formula of the specification limit is shown in formula I;

[0053] 6√R formula I;

[0054] Wherein, R is the length of the detection section, in kilometers (km).

[0055] Among them, the elevation data is updated after the second re-survey confirmation. Specifically, if the elevation difference of the measuring section exceeds the specification limit when it is measured for the first time, it is necessary to measure the elevation difference of the measuring section again. If the re-measurement result is consistent with the first measurement result, the elevation data is updated based on the first measurement result.

[0056] Specifically, starting from the control points of the line control network after re-survey, the height difference of each section is measured through the control points to be measured in each area. The entire regional control network is precisely adjusted using level adjustment software to calculate the elevation of the control points of the regional control network.

[0057] S2. Determine the differential settlement area based on the elevation settlement values ​​and geological conditions of the line control network control points remeasured in step S1, and bury two groups of regional control points on both sides of the differential settlement area; wherein, the positions where the two groups of regional control points are buried are 1.5Km-2.5Km away from other areas on both sides of the differential settlement area.

[0058] In addition, the regional control points are selected at stable locations far away from the project construction impact area and on buildings with stable settlement. Buildings with stable settlement include existing bridge piers, culverts, house foundations or signal tower foundations outside the construction impact area.

[0059] Among them, the regional control points are buried by implanting stainless steel observation piles later or using existing control points. Each group of regional control points should be evenly distributed with no less than 3 control points, so as to facilitate mutual detection of height differences in the measuring sections during later measurements to determine the stability of the regional control points and ensure that the control point data is accurate. Among them, the existing control points can be, for example, pier settlement observation piles.

[0060] Among them, the control point observation mark is implanted in the building or structure with a handheld electric drill. The drilling position is perpendicular to the buried surface and the depth is not less than 10cm. The hole diameter must be 4mm larger than the diameter of the observation mark. After the hole is formed, it must be rinsed with clean water. When there is no water in the hole, the mixed high-strength anchor is poured into the hole. Finally, the observation mark is inserted into the center of the hole to allow the anchor to fully wrap the observation mark.

[0061] S3. Use the elevation of the line control network after re-survey to continuously measure the regional control points, and then use the national second-class leveling method to measure the height difference of each section and calculate the elevation of the regional control network control points as the detection constraint points of the settlement area control points; among them, continuous measurement means that the regional control network control points are included in the line control network to calculate the elevation together. Among them, the constraint points are used as the starting and ending known points of the elevation calculation, and then calculate the other elevations to be measured.

[0062] The calculation process is divided into two steps. The first step is to check whether the measurement results meet the standard limit requirements, and the second step is to adjust the results. If the first step does not meet the standard limit requirements, re-measure until the standard limit requirements are met before proceeding to the second step.

[0063] Among them, the standard tolerance includes the closure error tolerance of the conforming route as shown in formula II, the non-conformity tolerance of the round-trip measurement height difference as shown in formula III, and the loop closure error tolerance as shown in formula IV;

[0064] 4√L formula II;

[0065] Where, L is the length of the attached route, in kilometers (km);

[0066] 4√k formula III

[0067] Where, k is the length of the measurement route, in kilometers (km);

[0068] 4√F formula IV;

[0069] Where F is the length of the loop in kilometers (km).

[0070] The calculation steps of the result adjustment are as follows:

[0071] fh=Σh-(H end-H start)

[0072] fh<4√L

[0073] V=-(Li / L*fh)

[0074] h = hi + V

[0075] Hwait=Hstart+hchange

[0076] Among them, fh is the closing error of the matching leveling; Hstart is the elevation value of the starting point of the line; Hend is the elevation value of the end point of the line; V is the correction value of the height difference of the measuring section; Li is the length of the measuring section, in kilometers (km); L is the length of the matching line, in kilometers (km); h is the height difference of the measuring section after correction; hi is the uncorrected height difference of the measuring section; Hto is the elevation value of the point to be determined.

[0077] S4. During the construction period, regional control points are used to regularly check the control points in the differential settlement area. The measurement method adopts the national second-class leveling method. If the settlement of the control points in the settlement area is found to exceed the standard limit of the measuring section, the elevation data of the control points are updated according to the measurement data.

[0078] The above description is only a preferred embodiment of the present application and is not intended to limit the present application. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present application should be included in the protection scope of the present application.

Claims

1. A method for measuring the elevation control network of a differentiated settlement area, characterized in that: The following steps are involved: S1. Re-survey the line elevation control network: Use the national second-class leveling method to re-survey the line elevation control network and calculate the height difference of the control point. If the height difference of the control point exceeds the standard limit, re-survey and confirm it for the second time before updating the elevation data. S2, determining the differential settlement area according to the elevation settlement values ​​of the line control network control points remeasured in step S1 and the geological conditions, and burying two groups of regional control points on both sides of the differential settlement area; S3, use the elevation of the line control network after re-survey to continuously measure the regional control points, and then use the national second-class leveling method to measure the height difference of each section and calculate the elevation of the control points of the regional control network as the detection constraint points of the settlement area control points; S4. During the construction period, regional control points are used to regularly check the control points in the differential settlement area. The measurement method adopts the national second-class leveling method. If the settlement of the control points in the settlement area is found to exceed the standard limit of the measuring section, the elevation data of the control points are updated according to the measurement data.

2. A method for measuring a differential subsidence area elevation control network as claimed in claim 1, characterized in that: In the step S1, the elevation control network is formed by measuring a plurality of elevation control point paths; the re-measurement method is to measure from a starting control point through a plurality of intermediate control points to another end control point to complete the forward measurement route, and then measure from the end control point through a plurality of intermediate control points to the starting control point to complete the return measurement route to complete the control network measurement.

3. A method for measuring a differential subsidence area elevation control network as claimed in claim 1, characterized in that: In the step S1, the calculation formula of the specification limit deviation is shown in Formula I; 6√R formula I; Where R is the length of the detection section, in kilometers (km).

4. A method for measuring a differential settlement area elevation control network according to claim 1, characterized in that: In the step S1, the elevation data is updated after the second re-measurement is confirmed. Specifically, if the elevation difference of the measuring section exceeds the standard limit, it is necessary to measure the elevation difference of the measuring section again. If the re-measurement result is consistent with the first measurement result, the elevation data is updated based on the first measurement result.

5. A method for measuring a differential subsidence area elevation control network as claimed in claim 1, characterized in that: In the step S2, the locations where the two groups of regional control points are buried are 1.5km-2.5km away from both sides of the differential settlement area and other areas; and / or The regional control point is selected at a stable location far away from the project construction impact area and on a building with stable settlement; and / or, the building with stable settlement includes one of the existing bridge piers, culverts, house foundations or signal tower foundations outside the construction impact range.

6. A method for measuring a differential subsidence area elevation control network according to claim 1, characterized in that: In the step S2, the regional control points are buried by implanting stainless steel observation piles later or using existing control points. Each group of regional control points should be evenly distributed with no less than 3 control points.

7. A method for measuring a differential subsidence area elevation control network according to claim 1, characterized in that: In the step S3, the continuous measurement includes the control points of the regional control network in the line control network to calculate the elevation together; The calculation process is divided into two steps. The first step is to check whether the measurement results meet the standard tolerance requirements, and the second step is to calculate the results. If the first step does not meet the standard tolerance requirements, re-measure until the standard tolerance requirements are met before proceeding to the second step.

8. A method for measuring a differential settlement area elevation control network according to claim 7, characterized in that: The standard tolerances include the closure error tolerance of the conforming route as shown in formula II, the non-conformity tolerance of the round-trip height difference as shown in formula III, and the loop closure error tolerance as shown in formula IV; 4√L formula II; Where, L is the length of the attached route, in kilometers (km); 4√k formula III Where, k is the length of the measurement route, in kilometers (km); 4√F formula IV; Where F is the length of the loop in kilometers (km).

9. A method for measuring a differential settlement area elevation control network according to claim 7, characterized in that: The calculation steps of the result adjustment are as follows: fh=Σh-(H end-H start) fh<4√L V=-(Li / L*fh) h = hi + V Hwait=Hstart+hchange Among them, fh is the closing error of the matching leveling; Hstart is the elevation value of the starting point of the line; Hend is the elevation value of the end point of the line; V is the correction value of the height difference of the measuring section; Li is the length of the measuring section, in kilometers (km); L is the length of the matching line, in kilometers (km); h is the height difference of the measuring section after correction; hi is the uncorrected height difference of the measuring section; Hto is the elevation value of the point to be determined.

10. A method for measuring a differential settlement area elevation control network according to claim 1, characterized in that: In the step S3, the constraint points are used as the starting known points and the ending known points for elevation calculation, and then other elevations to be measured are calculated.

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