A method for measuring a hybrid fixed and free station corner network

Abstract

The application discloses a fixed and free station mixed edge corner network measurement method. First, a pair of plane control points are arranged on the double side walls of a tunnel hole at intervals, after the control points are arranged, when a tunnel hole plane network is measured, a total station is erected on the control points according to the cross traverse network measurement method, and a plurality of nearby control points are observed (the dotted line in FIG. 1 is the observation direction of the fixed station at the control point), then the total station is arranged on the middle position between the adjacent two pairs of control points through a foot support according to the nearest principle, eight nearby control points are observed, after the observation is completed, the total station is erected on the next control point to observe a plurality of nearby control points, the above-mentioned fixed station and free station alternating measurement process is repeated, and the whole network through measurement of the tunnel is completed. The application has the advantages of more redundant observation numbers, better network shape strength, better control belt control network lateral swing effect and the like.

Description

Technical Field

[0001] This invention patent belongs to the field of engineering surveying technology, and in particular to a method for planar control surveying inside ultra-long railway tunnels. Background Technology

[0002] In recent years, with the increasing scale of railway construction in plateau and mountainous areas of my country, the number of ultra-long railway tunnels with high altitude, large elevation differences, and deep burial depths has also increased. To ensure the successful completion of these ultra-long railway tunnels, various measures are needed to improve the lateral connection accuracy, including optimizing the shape of the internal plane control network. Currently, plane control surveying in long tunnels mainly uses cross traverse networks, traverse loop networks, or free-station corner intersection networks. These three types of plane control networks have certain advantages in controlling the lateral sway of the strip-shaped corner network. However, the first two types of surveying networks have numerous traverse edges parallel to the tunnel's two sidewalls, and the horizontal observation values ​​of these edges are significantly affected by lateral refraction. The last type of network is affected by the dust, humid environment, and poor ventilation conditions inside the tunnel, resulting in a significantly shortened total station range. Therefore, the longitudinal spacing between control points in this surveying network is relatively short. To effectively improve the lateral connection accuracy of ultra-long railway tunnels, a new type of internal plane control surveying network with more redundant observations, better network strength, and less lateral sway should be studied. Summary of the Invention

[0003] In view of the above-mentioned shortcomings of common tunnel planar control network shapes, the purpose of this invention is to provide a measurement method for a hybrid corner network of fixed and free stations. The aim is to combine the advantages of multiple network shapes to establish a new type of tunnel planar control network, namely a triangular intersection network of free and fixed stations, which has the advantages of having a large number of redundant observations, good network strength, obvious effect on controlling the lateral swing of the control strip network, and simple point layout method.

[0004] The purpose of this invention patent is achieved through the following means.

[0005] A method for measuring tunnel sidings using a hybrid fixed and free station network, wherein the hybrid fixed and free station network is a regular siding intersection network, which includes tunnel entrance control points, tunnel interior control points, and free station points; two or more tunnel entrance control points are set up at both the tunnel entrance and exit, and a pair of plane control points (tunnel interior control points) are set up every 250m on both sides of the tunnel interior; the free station points are spaced 250m apart and selected at the tunnel centerline.

[0006] After the control points are set up, the tunnel's internal plane control network is measured, including two parts: the measurement of the connection between the inside and outside of the tunnel and the measurement of the internal plane control.

[0007] Surveying the connection between the inside and outside of the tunnel:

[0008] The survey begins at the tunnel entrance control point. First, a total station is set up at the third tunnel entrance control point to observe the first and second tunnel entrance control points, as well as the first pair of internal control points. This process is called fixed-station surveying. Then, a location with good visibility is selected between the first pair of internal control points at the tunnel entrance and the first, second, and third tunnel entrance control points as the fourth tunnel entrance control point. A tripod is then set up to house the total station. Next, the first, second, and third tunnel entrance control points, as well as the nearest first pair of internal control points, are observed. This process is called free-station surveying. Then, fixed-station surveys are conducted sequentially at the first pair of internal control points. In addition to observing the second pair of internal control points, the second tunnel entrance control point also needs to be observed. When conducting free-station surveys at the first free-station point located between the first and second pairs of internal control points, the first, second, and third pairs of internal control points, as well as the second and third tunnel entrance control points, need to be observed. This completes the horizontal connection surveying between the tunnel entrance and exit. For tunnels excavated in opposite directions, the above method is used for both the entrance and exit horizontal connection surveying.

[0009] In-tunnel horizontal control survey:

[0010] After completing the above-mentioned horizontal connection measurement between the inside and outside of the tunnel, the horizontal control points inside the tunnel are observed. First, the instrument is set up on the second pair of control points inside the tunnel, and fixed station measurements are performed on the two nearby pairs of control points. Then, following the free station method, a total station is set up on a tripod at the second free station between the two pairs of control points inside the tunnel, and free station corner intersection measurements are performed on the eight nearby control points inside the tunnel. Then, the total station is set up on the third pair of control points inside the tunnel, and the four nearby control points inside the tunnel are observed again. Then, the eight nearby control points inside the tunnel are observed again at the third free station... The above measurement process of alternating fixed station and free station measurements is repeated until the horizontal control measurement of the tunnel from the entrance or exit end to the breakthrough surface is completed.

[0011] The control point inside the tunnel is set at the tunnel cable trench, and a forced centering device is required to be buried. The device is required to be able to install both a precision prism and a total station.

[0012] Compared with the prior art, the beneficial effects of the present invention are:

[0013] Using the free and fixed station intersection network method of this patented invention, during observation, only one additional free station observation is needed at the midpoint between two adjacent pairs of control points in a conventional cross-traverse network (e.g., Figure 1As shown in the figure, it does not require significant changes to the traditional measurement process. Compared with common intra-tunnel planar control network types such as cross traverse networks, traverse loop networks, and free station corner intersection networks, this patented invention has advantages such as more redundant observations, better network strength, and better control of the lateral sway of the control strip network. Furthermore, the spacing, location, and number of control points are not significantly different from other common network types, making it easy to apply in actual engineering projects. Attached Figure Description

[0014] Figure 1 The intersection network of free and fixed stations with equilateral angles.

[0015] Figure 2 Schematic diagram of the planar connection between the inside and outside of the tunnel.

[0016] Figure 3 Schematic diagram of horizontal control surveying inside the tunnel. Detailed Implementation

[0017] To make the objectives, technical solutions, and advantages of this invention clearer and easier to understand, the invention patent will be further described below in conjunction with the accompanying drawings.

[0018] Figure 2 , Figure 3 The free survey stations 7, 10, and 13 are the first, second, and third free survey stations, respectively. Figure 2 In the tunnel, control points 1, 2, 3, and 4 at the tunnel entrance are not collinear with the tunnel centerline, nor are they collinear with the line connecting the control points inside the tunnel. Any three of points 1, 2, 3, and 4 are not collinear, and the distances of points 1, 2, 3, and 4 from the tunnel entrance are getting closer and closer. Figure 3 In the middle, the first, second, third, and fourth pairs of control points inside the tunnel are 5, 6, 8, 9, 11, 12, 14, and 15.

[0019] like Figure 1 As shown, the new type of tunnel internal plane control network is essentially a hybrid network of intersecting traverse networks and free station intersection networks, referred to as a free and fixed station conformal intersection network. The control network includes control points at the tunnel entrance, control points within the tunnel, and free station points. Two or more control points are required at both the tunnel entrance and exit. Inside the tunnel, a pair of plane control points are placed approximately every 250m on both sides (the longitudinal spacing can be adjusted according to site conditions). Internal control points are generally located at the tunnel cable trenches and require the installation of forced centering devices, which should be able to accommodate both precision prisms and total stations. The spacing between free station points is approximately 250m, ideally located near the tunnel centerline, roughly equal to the spacing between the internal control points at both the large and small mileage ends.

[0020] First, a pair of horizontal control points are set up at regular intervals on both sides of the tunnel. After the control points are set up, when measuring the horizontal network inside the tunnel, the total station is first set up on the control points according to the measurement method of the cross traverse network, and observations are made on several nearby control points. Figure 1 The dashed line indicates the observation direction of the fixed station at the control point. Then, following the principle of proximity, the total station is set up on a tripod between two adjacent pairs of control points to conduct free station observations of the eight nearby control points. Figure 1 (The solid line in the center is the observation direction of the free station). After the observation is completed, the total station is set up on the next control point to observe several nearby control points. The above measurement process of alternating between fixed stations and free stations is repeated until the entire tunnel network connection measurement is completed.

[0021] After the control points are established, the horizontal control network inside the new tunnel is measured, including two parts: horizontal connection measurement inside and outside the tunnel and control measurement inside the tunnel. The measurement begins from the control point at the tunnel entrance. First, the instrument is set up at the control point, such as... Figure 2 As shown at station 3, observations are made on the remaining control points 1 and 2 at the tunnel entrance, as well as the first pair of control points 5 and 6 inside the tunnel. This process is called fixed-station measurement. A location with good visibility (4) is selected between the first pair of control points inside the tunnel entrance and the tunnel entrance control point. A tripod is then set up to house the total station. Next, observations are made on control points 1, 2, and 3 at the tunnel entrance, as well as the nearest first pair of control points 5 and 6 inside the tunnel. This process is called free-station measurement. Then, fixed measurements are performed sequentially on the first pair of control points 5 and 6 inside the tunnel. In addition to observing control points 8 and 9 inside the tunnel, control point 2 at the tunnel entrance also needs to be observed. When performing free-station measurements at the first free-station station 7, located between the first and second pairs of control points inside the tunnel, in addition to observing control points 5, 6, 8, 9, 11, and 12 inside the tunnel, control points 2 and 3 at the tunnel entrance also need to be observed. This completes the horizontal connection measurement between the tunnel entrance and the outside. For tunnels excavated in opposite directions, the above method is used for the horizontal connection measurement between the entrance and the exit.

[0022] After completing the above-mentioned horizontal connection measurement between the inside and outside of the tunnel, the horizontal control points inside the tunnel will be observed, such as... Figure 3As shown, firstly, the instrument is set up successively on the second pair of control points 8 and 9 inside the tunnel, and fixed station measurements are taken on the four nearby control points 5, 6, 11, and 12. Then, following the free station method, the total station is set up on a tripod at the second free station 10, which is located between the two pairs of control points 8 and 9 and 11 and 12, and free station corner intersection measurements are taken on the eight nearby control points 5, 6, 8, 9, 11, 12, 14, and 15 inside the tunnel. Then, the total station is set up successively on the third pair of control points 11 and 12 inside the tunnel, and the four nearby control points 8, 9, 14, and 15 inside the tunnel are observed again. Then, the eight nearby control points inside the tunnel are observed again at the third free station 13... The above measurement process of alternating fixed station and free station measurements is repeated until the tunnel plane control measurement from the entrance (exit) end to the breakthrough surface is completed.

Claims

1. A method for measuring a hybrid edge-angle network using fixed and free stations, characterized in that, The fixed and free station hybrid edge-angle network is a regular edge-angle intersection network, which includes tunnel entrance control points, tunnel interior control points, and free station points. Two or more tunnel entrance control points are set up at both the tunnel entrance and exit. A pair of plane control points, i.e. tunnel interior control points, are set up every 250m on both sides of the tunnel. The free station points are spaced 250m apart and are selected at the centerline of the tunnel. After the control points are set up, the tunnel's internal plane control network is measured, including two parts: the measurement of the connection between the inside and outside of the tunnel and the measurement of the internal plane control. Surveying the connection between the inside and outside of the cave: Starting from the tunnel entrance control point, the total station is first set up at the third tunnel entrance control point (3) to observe the first and second tunnel entrance control points (1, 2) and the first pair of tunnel control points (5, 6). This process is called fixed station measurement. A location with good visibility is selected between the first pair of tunnel control points and the first, second, and third tunnel entrance control points as the fourth tunnel entrance control point (4). The tripod is set up to place the total station. Then, the first, second, and third tunnel entrance control points (1, 2, 3) and the nearest first pair of tunnel control points (5, 6) are observed. This process is called free station measurement. Then, at the first... Fixed station measurements were carried out sequentially at the control points (5, 6) inside the tunnel. In addition to observing the second pair of control points (8, 9) inside the tunnel, the second tunnel entrance control point (2) also needed to be observed. When conducting free station measurements at the first free station (7) located between the first pair of control points inside the tunnel and the second pair of control points inside the tunnel, the first, second, and third pairs of control points inside the tunnel (5, 6, 8, 9, 11, 12) and the second and third tunnel entrance control points (2, 3) needed to be observed. This completed the measurement of the plane connection between the inside and outside of the tunnel. For tunnels excavated in opposite directions, the above method was used for the plane connection measurement between the entrance and exit of the tunnel. In-tunnel horizontal control survey: After completing the above-mentioned horizontal connection measurement between the inside and outside of the tunnel, the horizontal control points inside the tunnel are observed. First, the instrument is set up on the second pair of control points (8, 9) inside the tunnel, and fixed station measurements are taken at the two nearby pairs of control points (5, 6, 11, 12). Then, following the free station method, the total station is set up on a tripod at the second free station (10) between the two pairs of control points (8, 9, 11, 12) inside the tunnel, and the measurements are taken at the eight nearby control points (5, 6, 8, 9, 11, 12). 9, 11, 12, 14, 15) Perform free station corner intersection measurement, and then set up the total station on the third pair of tunnel control points (11, 12) one after another, and observe the four adjacent tunnel control points (8, 9, 14, 15) again. Then observe the eight nearby tunnel control points at the third free station (13)... Repeat the above measurement process of alternating between fixed station and free station measurement until the tunnel plane control measurement from the tunnel entrance or exit end to the breakthrough surface is completed.

2. The method for measuring a hybrid edge-angle network of fixed and free stations according to claim 1, characterized in that, The control point inside the tunnel is set at the tunnel cable trench, and a forced centering device is required to be buried. The device requires the installation of a precision prism or a total station.

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